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Aluminium Profile Type Router - Initial questions
Hi Everyone,
First post on this forum and CNC in general. There seems to be a huge amount of knowledge on this forum, and I feel very out of my depth but learnt a lot lurking here for the past couple of weeks, from a base of zero !
Not sure if I should be creating my own build log as its just a couple questions for now.
So I'm looking at building a CNC router for perhaps 75% soft/hard wood, 25% aluminium use. I mainly work with wood on a hobby level.
I don't have any CAD drawings etc yet, all just paper! sketches but the plan is in the style of the 3d tek heavy mill with some inspiration from here.
wasteboard size 1080 x 1000mm
Here are the parts I'm planning to use this far;
Hiwin 20mm Linear Rails/ HGW20CA Carriages @ 900mm (for X & Y Axes)
2005 Ball Screws @ 900mm for X and Y ( 2 on Y axis rails)
BF15/BK15 Mounts
1605 Ball Screw for Z Axis
Z Axis TBC, but likely SC16LUU type bearings
4 x Nema 23 4NM stepper motors
Purchased so far: Aluminium Profile
2 pieces of 40 x 120 @ 1000mm (Y axis)
4 pieces of 40 x 40 @ 1000mm (X axis supports)
1 pieces 80 x 80 @ 1200mm for X Gantry (will rest on aluminium plate on linear rails)
Parts which I need some assistance with (so far...)
I have minimal electrical experience this far, aside from domestic 240V type.
So looking for comments on the below - will it work together etc. I'll probably not purchase any of the below until physical build well under way but getting an idea of design and cost.
Laptop with Ethernet..
AXXB-E Control board - I like this as it works with UCCNC and Mach3/4, plus doesn't require a breakout board I believe. Does anyone have good/bad experience with this?
Stepper Drivers - Would something like CW8060 from cnc 4 you deliver good performance from the motors? Anything better at similar price point? Stall detection sounds like a must but not clear if this has it?
Power Supply - What Voltage to drive the motors at for optimum performance? and any PSU recommended?
Thanks!
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Re: Aluminium Profile Type Router - Initial questions
Hi CNCRY,
Welcome to the forum!
Usual advice is to hold off on further purchases until you've got the design finalised and pretty confident about each electronic component - changes upstream can irritatingly change what you need on the mechanicals, and electronics have a way of updating while you're building, so best to buy once when you need it rather than in advance, so you've got the right idea there.
I suggest you read through the build log section of the forum; you should be able to look at the 3D Tek design and notice where they've done the right thing and where they've skimped. You've already identified that ballscrews are a more appropriate drive option for example - but there are a few design choices about the Z axis that I wouldn't emulate.
Regards your rails and screws choice, the rails seem appropriate, the screws are about right, but in this size I'd also consider 16mm screws and 10mm pitch options, but all depends on if you want to use pulleys. There are a few calculations you can do to help you determine whats best for your use, but you'll pick this up in the build logs.
You're correct that the AXBB-E has a breakout board built in and seems to get a good rep (I haven't got one!), but also compare against other options such as built-in controllers and say UC400eth with a cheap breakout or expensive breakout. Generally I'd say stick with Ethernet based controllers, unless you're going down the LinuxCNC route.
Voltage and PSU specs are again very common topics in the build logs so I won't delve into it here (but bookmark threads and page numbers when you find these things!!). Generally unregulated PSUs are preferred, a lot of users build their own, or purchase AC drives so you only need a toroidal.
Hope that helps!
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Generally I'd say stick with Ethernet based controllers, unless you're going down the LinuxCNC route.
Would you mind expanding on this?
There are plenty of cards for linuxcnc ie .Mesa 7i92,7i96,7i95 ,7i76e .
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
Clive S
Would you mind expanding on this?
Hah! Yes, "Unless you're going down the linuxCNC route in which case I have no idea" :P
Reading it back it sounds like I'm saying don't use ethernet with LinuxCNC - it was meant as an "if you're using LinuxCNC there may be more appropriate options like onboard PCI cards".
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Re: Aluminium Profile Type Router - Initial questions
Thanks Andy,
I'm trying to figure out whether 2005 or or 2010 ballscrew would be better, or 1605/1610 (which seems to be less available pre machined). I don't plan to use pulleys.
Problem is all calculations seems to lead to other values which I don't know what I'm aiming for!
So filling out a speeds and feed calc for say hardwood @ 20,000rpm spindle I get min/max of 9-11 M/min speed. Assume this is the cutting speed and the rapid people refer to are movement between cuts.
I also used zapp calculator to get critical speed of 20mm diameter ballscrew with 750mm spacing between supports giving 1548 RPM.
From forums someone gives 2010 screw @ 1348 RPM = 2.15m/min, so would the motor need to at appox 6740rpm to achieve that?
But also the motor Voltage driven needs to be known to get an idea of rpm which can be achieved?
I also don't know the final weight of the gantry, I'd estimate say 20Kg based on extrusion weight + spindle and alum plate.
On another note - have I already got off to a bad start using the non-heavy type of aluminium profile. This was from KJN, I intend to add plate/strengthening to make it more rigid.
Just installed fusion 360 to see if I can learn to create my design in diagram form:)
Ryan
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
CNCRY
I'm trying to figure out whether 2005 or or 2010 ballscrew would be better, or 1605/1610 (which seems to be less available pre machined). I don't plan to use pulleys.
Meh, get a custom quote from Fred and he'll machine whatever you want, it'll still probably be cheaper than the pre-machined, and you'll have a quality product from a trusted vendor.
Quote:
Originally Posted by
CNCRY
So filling out a speeds and feed calc for say hardwood @ 20,000rpm spindle I get min/max of 9-11 M/min speed. Assume this is the cutting speed and the rapid people refer to are movement between cuts.
Yep. No feeds and speeds calculator will ever give you rapid speed recommendations. Do remember that it will also depend on how many flutes your cutter has.
Quote:
Originally Posted by
CNCRY
From forums someone gives 2010 screw @ 1348 RPM = 2.15m/min, so would the motor need to at appox 6740rpm to achieve that?
Then that someone is a tit and can't do maths. It was probably me. The 2010 means that the outside diameter of the screw is 20mm, and the pitch is 10mm. In one turn of the screw, the ballnut will move 10mm. So 1348 turns per minute equals 13480mm/min = 13.48m/min.
Quote:
Originally Posted by
CNCRY
But also the motor Voltage driven needs to be known to get an idea of rpm which can be achieved?
Its less about the voltage, more about how much torque you have left when you get up to those RPMs, which then dictates how quickly you can accelerate and decelerate. Whilst I spent a lot of time doing the calculations, I still ended up with the same motors as everyone else with the machine size, so for starters find a decent build about the same size and steal their motor and PSU configuration :P Work forwards from that.
Quote:
Originally Posted by
CNCRY
I also don't know the final weight of the gantry, I'd estimate say 20Kg based on extrusion weight + spindle and alum plate.
Quite machine dependent, but I'd guess you're lowballing it. A 2.2kW Spindle is approx 8kg alone. Rails + Ballscrews + Plates + Motors + Extrusion should be a good ballpark. Maybe nearer 30-40kg?
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Re: Aluminium Profile Type Router - Initial questions
Hi Ryan,
Let me just say from the start that the Heavy Mill 3DTEK as got some serious issues and it's far from its name suggests.
First off scrap the Z-axis altogether it's load of rubbish and far too flimsy. The Z-axis is THE most important part of the machine because it's where all the action happens. If it's weak then it doesn't matter if the rest of the machine is built like a tank your cutting will always suffer.
Also, no point using Hi-win profiled linear rails on other axis if going to use a round rail on Z-axis, use either all-round or all profiled. You are wasting your money mixing them.
Next is the Gantry sides, they are also weak and flimsy. They will resonate and flex which again transfers into the cut. To be honest the whole gantry is on the weak side and could easily be made stronger with a design change. Even the Light profile will work if you used an L shaped design.
Regards the ball-screws you will be better with 16mm x 10mm pitch for a wood router at this size. 10mm pitch will easily allow you to cut aluminum without any problems. Whereas 5mm would be too slow for cutting wood correctly.
You don't need 20mm for a machine this size and it will only rob you of power and speed because of the extra inertia of the ball-screw. It takes more power to accelerate and deaccelerate than 16mm and it does make a big difference to performance.
Regards the electrics and controller then always go with Ethernet if you can afford the extra, it's much more stable than USB or parallel port.
Andy mentions Voltage isn't so important but I'm afraid he's wrong, It's very important to the speed and torque you'll get from a stepper motor. The torque you get from a motor is proportional to voltage so if you increase the voltage the torque will also rise, up to a point. To get high speeds from a stepper you need voltage which is why we try to use higher voltage drives so we can boost voltage. Obviously there is a limit dependant on motor/drive specs etc but in general, more volts = higher rpm which is better for a router.
Regards the Motor, drives and PSU spec then there is a well-proven spec for machines this size which has been used for a long time on this forum. Which I'm happy to help you with. However, I'd also advise you to consider looking at Closed-loop steppers as they have come down in price quite a lot and are much better than the standard stepper systems. This could change things a little regards PSU etc depending on which you go for. So go have a look at them if you haven't already and let us know your thinking.?
BIGGEST ADVISE is don't buy anything else until your 100% sure it's correct. Also don't buy electrics until needed as your wasting warranty and things change fast these days regards controllers/software and drives you could end up with a better system by waiting until needed.
Don't be afraid to ask questions no matter how dumb you may think they sound.
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Re: Aluminium Profile Type Router - Initial questions
Thanks for bearing with me, now I have the whole idea in my head I'm keen to start building , but want to do it right first time so remaining patient, and re-thinking the design.
Is Fred the BST automation aliexpress store? What sort of lead time do people get with him and is there a ballpark % amount of import duty etc to be expected?
That RPM calculation was from a U.S forum in IPM, and was clearly wrong then. Thats clear now, so with the 10mm pitch I'd need to aim for 1000rpm to get 10m/s cutting speed, which should be about right for a 2 flute cutter in hardwood. While Aluminium would need to aim for 5m/s or 500rpm at the motor?
So from most similar builds I have seen everyone ends up with 3/4NM Nema 34 motors, but there is variation in how they can be driven.
Trying to pin down some aspects so I can then design around those.
You are right on gantry weight . Profile is 8kg + 8Kg spindle + perhaps 10kg rails and carriages + aluminium plate + motor - more like 35Kg.
Ryan
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
JAZZCNC
Hi Ryan,
Let me just say from the start that the Heavy Mill 3DTEK as got some serious issues and it's far from its name suggests.
First off scrap the Z-axis altogether it's load of rubbish and far too flimsy. The Z-axis is THE most important part of the machine because it's where all the action happens. If it's weak then it doesn't matter if the rest of the machine is built like a tank your cutting will always suffer.
Also, no point using Hi-win profiled linear rails on other axis if going to use a round rail on Z-axis, use either all-round or all profiled. You are wasting your money mixing them.
Next is the Gantry sides, they are also weak and flimsy. They will resonate and flex which again transfers into the cut. To be honest the whole gantry is on the weak side and could easily be made stronger with a design change. Even the Light profile will work if you used an L shaped design.
Regards the ball-screws you will be better with 16mm x 10mm pitch for a wood router at this size. 10mm pitch will easily allow you to cut aluminum without any problems. Whereas 5mm would be too slow for cutting wood correctly.
You don't need 20mm for a machine this size and it will only rob you of power and speed because of the extra inertia of the ball-screw. It takes more power to accelerate and deaccelerate than 16mm and it does make a big difference to performance.
Regards the electrics and controller then always go with Ethernet if you can afford the extra, it's much more stable than USB or parallel port.
Andy mentions Voltage isn't so important but I'm afraid he's wrong, It's very important to the speed and torque you'll get from a stepper motor. The torque you get from a motor is proportional to voltage so if you increase the voltage the torque will also rise, up to a point. To get high speeds from a stepper you need voltage which is why we try to use higher voltage drives so we can boost voltage. Obviously there is a limit dependant on motor/drive specs etc but in general, more volts = higher rpm which is better for a router.
Regards the Motor, drives and PSU spec then there is a well-proven spec for machines this size which has been used for a long time on this forum. Which I'm happy to help you with. However, I'd also advise you to consider looking at Closed-loop steppers as they have come down in price quite a lot and are much better than the standard stepper systems. This could change things a little regards PSU etc depending on which you go for. So go have a look at them if you haven't already and let us know your thinking.?
BIGGEST ADVISE is don't buy anything else until your 100% sure it's correct. Also don't buy electrics until needed as your wasting warranty and things change fast these days regards controllers/software and drives you could end up with a better system by waiting until needed.
Don't be afraid to ask questions no matter how dumb you may think they sound.
Appreciate the advice JazzCNC
Heavy Mill was my initial idea as I could see how it was constructed, plus I assumed must be a sufficiently good design to sell:) I'll not be copying it's Z axis in that case, and will design on the same rail setup instead. As I just mentioned in reply to Andy - im's trying to establish some "fixed" ideas and design around that, but X changes so does Y!
So one thing I did notice on heavy mill were weak side's so my design there is similar to Andys log = http://www.mycncuk.com/attachment.ph...3&d=1573338796 . That is rails on top on the extrusion, then a carriage and aluminium block which the gantry rail site on top of,and fixed using side plates .
I'll be looking into 1610 ballscrew based on both the replys now.
Do closed loop steppers work with standard nema motors ? I'll take a look.
I'll be trying to draw this in a shareable format soon. But design steps wise, can I design/build the X/Y axis and gantry to a good standard, then consider the Z axis as the next "module" or is that a bad idea!
If I know the motors to be used, I can pretty much leave electronics until the build progresses, and certainly won't buy anything related to that yet.
Will my existing 120 x 40 profile with 40x40 cross pieces suffice for X/Y axis with extra bracing?
And with the L design for gantry - just thinking how I can incorporate the 90x90 profile, perhaps a 60x60 attached to it at the back?
Ryan
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
CNCRY
Is Fred the BST automation aliexpress store? What sort of lead time do people get with him.
Ryan
Ryan,
Yes, Fred is BST Automation. I fell of the sofa when my leadscrews and rails arrived in remote western Australia only 4 days after I paid for them. It often takes longer than that to get stuff from the state capitol Perth. You do pay quite a lot for delivery though and it's worth checking the different total cost for item + postage and 'free' postage for the same thing.
Don't forget that many Chinese businesses are closed at present because of the virus so delivery times at the moment are anybody's guess.
I don't know about import duties to Pommieland but make sure you know the total cost before comparing suppliers.
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
CNCRY
So one thing I did notice on heavy mill were weak side's so my design there is similar to Andys log =
http://www.mycncuk.com/attachment.ph...3&d=1573338796 . That is rails on top on the extrusion, then a carriage and aluminum block which the gantry rail site on top of,and fixed using side plates .
Yes, this is the L design I was suggesting, most of the L designs you'll see are based off my original design or someone else's who took from mine, it can be used both with or without Gantry sides and makes for a very stiff gantry with easy rail mounting etc. When mounting directly to the bearings just bear in mind access to the bearings bolts when deciding the bearing plate length. I've seen several designs that missed this little detail, which is why it's a good idea to draw it in cad to catch these things.
Quote:
Originally Posted by
CNCRY
Do closed loop steppers work with standard nema motors ? I'll take a look.
No closed loop steppers have an encoder on the back which goes to the matching drives. Also often closed loop steppers are 3 phase steppers with smaller step angle of 0.9 or 1.2 deg whereas typical stepper is 2 phase. with 1,8deg step. The difference being closed-loop are smoother.
Quote:
Originally Posted by
CNCRY
I'll be trying to draw this in a shareable format soon. But design steps wise, can I design/build the X/Y axis and gantry to a good standard, then consider the Z axis as the next "module" or is that a bad idea!
Yes you can but I wouldn't recommended it because your better designing the whole thing in CAD to see if anything clashes.
Quote:
Originally Posted by
CNCRY
If I know the motors to be used, I can pretty much leave electronics until the build progresses, and certainly won't buy anything related to that yet.
All you really need to know is the motor frame size ie: NEMA 23 or 34. Now I've seen you mention Nema 34 is what you need.! This would be bad for a machine this size and mistake often made by new builders are thinking bigger is better, it's not.!
NEMA 34 motors require a much higher voltage to get the RPM needed for a router. A 4Nm NEMA 23 will perform much better than a 4Nm Nema 34 at the same voltage.
Quote:
Originally Posted by
CNCRY
Will my existing 120 x 40 profile with 40x40 cross pieces suffice for X/Y axis with extra bracing?
And with the L design for gantry - just thinking how I can incorporate the 90x90 profile, perhaps a 60x60 attached to it at the back?
Yes, the 120x40 and 40x40 could be used for the frame with bracing.
Regards the Gantry then Bolting 60x60 onto the back won't do anything other than add weight. To get the stiffness and height you need one piece flat with the other bolted on top. So either buy a wider piece for the bottom and put the 90x90 on top or start again with 2 x 45 x 90.
I'm assuming that your using BR range profile because of the 90mm. This is good because when using 16mm screws then the BK End bearings mounting holes will line up with the 45mm slot spacing. If you used the IR with 40mm slot spacing then you would have to make plates or drill the profiles to bolt the bearings on.
It's these little things that catch you out and cause more work. Hence why drawing in CAD can save many wasted days and money.
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2 Attachment(s)
Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
JAZZCNC
Yes, this is the L design I was suggesting, most of the L designs you'll see are based off my original design or someone else's who took from mine, it can be used both with or without Gantry sides and makes for a very stiff gantry with easy rail mounting etc. When mounting directly to the bearings just bear in mind access to the bearings bolts when deciding the bearing plate length. I've seen several designs that missed this little detail, which is why it's a good idea to draw it in cad to catch these things.
No closed loop steppers have an encoder on the back which goes to the matching drives. Also often closed loop steppers are 3 phase steppers with smaller step angle of 0.9 or 1.2 deg whereas typical stepper is 2 phase. with 1,8deg step. The difference being closed-loop are smoother.
Yes you can but I wouldn't recommended it because your better designing the whole thing in CAD to see if anything clashes.
All you really need to know is the motor frame size ie: NEMA 23 or 34. Now I've seen you mention Nema 34 is what you need.! This would be bad for a machine this size and mistake often made by new builders are thinking bigger is better, it's not.!
NEMA 34 motors require a much higher voltage to get the RPM needed for a router. A 4Nm NEMA 23 will perform much better than a 4Nm Nema 34 at the same voltage.
Yes, the 120x40 and 40x40 could be used for the frame with bracing.
Regards the Gantry then Bolting 60x60 onto the back won't do anything other than add weight. To get the stiffness and height you need one piece flat with the other bolted on top. So either buy a wider piece for the bottom and put the 90x90 on top or start again with 2 x 45 x 90.
I'm assuming that your using BR range profile because of the 90mm. This is good because when using 16mm screws then the BK End bearings mounting holes will line up with the 45mm slot spacing. If you used the IR with 40mm slot spacing then you would have to make plates or drill the profiles to bolt the bearings on.
It's these little things that catch you out and cause more work. Hence why drawing in CAD can save many wasted days and money.
Thanks Jazz - going to spend the next week or so learning fusion 360 and actually drawing the thing:) Probably makes sense to learn to use CAD alongside building a CNC machine!
The Nema motor - that was me being a muppet. I do mean Nema 23 4NM.
I guess the hybrid steppers are perhaps £50 more each with a driver package then a normal stepper and decent driver, something like https://www.cnc4you.co.uk/Stepper-Mo...-Servo-Kit-4Nm. ?
RE: the profile, I spent a fair amount so far so would really want to avoid wasting . You are right its the BR as below with 45mm spacing, so will make mounting easier.
Attachment 27327
So do you mean
40x120L along the bottom with 90x90 on top. Notice the slot spacing on that is 40 so no way to direct join - but I guess joining plates at ends will do?
Attachment 27328
for BST automation shop, which as mentioned is probably not sending anything right now - something like
3 X Anti Backlash Ballscrew RM1610 -L1000mm with SFU1610 Ballnut + BK12 BF12 Support Unit + 1610 Nut Bracket + 6.35*10mm coupler shows as $141 + $107 shipping. $248 total. I've never order anything over a few £ from china - what import duty do people get hit with? Looks like VAT+2.5%?
Ryan
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
CNCRY
For BST automation shop, which as mentioned is probably not sending anything right now - something like
3 X Anti Backlash Ballscrew RM1610 -L1000mm with SFU1610 Ballnut + BK12 BF12 Support Unit + 1610 Nut Bracket + 6.35*10mm coupler shows as $141 + $107 shipping. $248 total. I've never order anything over a few £ from china - what import duty do people get hit with? Looks like VAT+2.5%?
When you're ready, email them for a quote with exact sizes.
I was also concerned about ordering from BST initially, but there are a lot of examples of people here using them. Jazz probably keeps them in business singlehandedly. You can pay with PayPal via AliExpress. AliExpress hold the PayPal payment in escrow until the package arrives and then you release it to the seller. You're also doubley protected by PayPal, and even further if you use a credit card, so it's really no risk at all.
I paid roughly £1100 delivered including all import duty for four ballscrews (30cm 1605, 1m 1610 and two 1m 2010s) with associated ballnuts, ballnut mounts, BK and BF bearings (upgraded to AC I think), all custom machined to my exact lengths and to allow pulleys, all of my hiwin 20mm linear rail (2x1.2m, 2x1m and 2x35cm) and 12 hiwin carriages, and a 2.2kW spindle plus VFD with collets and water pump and spindle mount.
Sounds like a lot of money, but those three things were the most expensive components and about 1/3rd of the total build cost.
I won't go into further detail about the import duty, but trust me don't be concerned. You'll get a text or email when the parcel arrives in the UK and you just pay online.
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Re: Aluminium Profile Type Router - Initial questions
For ref, AliExpress extended their new year holiday until February 18th.
See here for more information...
https://aliexpressblog.com/how-aliex...irus-outbreak/
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
AndyUK
When you're ready, email them for a quote with exact sizes.
I was also concerned about ordering from BST initially, but there are a lot of examples of people here using them. Jazz probably keeps them in business singlehandedly. You can pay with PayPal via AliExpress. AliExpress hold the PayPal payment in escrow until the package arrives and then you release it to the seller. You're also doubley protected by PayPal, and even further if you use a credit card, so it's really no risk at all.
I paid roughly £1100 delivered including all import duty for four ballscrews (30cm 1605, 1m 1610 and two 1m 2010s) with associated ballnuts, ballnut mounts, BK and BF bearings (upgraded to AC I think), all custom machined to my exact lengths and to allow pulleys, all of my hiwin 20mm linear rail (2x1.2m, 2x1m and 2x35cm) and 12 hiwin carriages, and a 2.2kW spindle plus VFD with collets and water pump and spindle mount.
Sounds like a lot of money, but those three things were the most expensive components and about 1/3rd of the total build cost.
I won't go into further detail about the import duty, but trust me don't be concerned. You'll get a text or email when the parcel arrives in the UK and you just pay online.
Thanks Andy - thats good to know. I'm spending a bit of time trying to learn fusion 360 and draw the thing now before I buy anything else !
I added an extra extrusion 120x40 to my order, so now have a 90x90 and 120x40 piece @1200mm to factor into the (sort of) L shape gantry design.
Ryan
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5 Attachment(s)
Re: Aluminium Profile Type Router - Initial questions
OK so I've figured out enough of Fusion 360 to model something - not going to win any awards but at least it's clearer and I can edit the design as needed.
Attachment 27376
Attachment 27377
Attachment 27378
Attachment 27379
Attachment 27380
The blocks on top of the X carriages are set to 40mm thick currently
All rails are 1000mm , to be adjusted if needed
Aluminium profile on gantry is 120 x 40 with 90x90 on top.
The purpose of the ballscrew and ballnut running inside gantry plate is to allow an L angle (or perhaps long brush) to be fixed to the extrusion above the screw and cover the ballscrew from dust/chips
*
Issues I'm thinking of so far is the the Z axis clearance isn't huge, 125mm from top of baseboard to bottom of gantry, although probably OK for my needs.
The Z design with rail on front and top is based on the fact Z clearance would be even lower if I put rails on top/bottom of profile. I plan to add extra C shaped plates to side of Z axis to strengthen - will it be enough/OK design?
Y axis travel is limited by how far forward Z is - losing about 275mm so probably need to bring the carriages closer together and gantry plates narrower, maybe mount motor to back of gantry extrusion instead with pulley.
Any comments on those bits? thanks
Aluminium profile arriving tomorrow - only thing I've ordered so far, but will be good to get a feel for size. Also built a 1.2m square workbench for it , 25mm ply top and 50x100 wooden frame on castors, hopefully that'll be rigid enough.
Ryan
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3 Attachment(s)
Re: Aluminium Profile Type Router - Initial questions
Hi All,
I've spent some more time on the design - moved the dual X motors to the back, and added a pulley based drive to the Y axis (borrowed from Andy's build log!)
Also shortened the plate fixing gantry to Y rails to give more Y cutting area. I expect I'll get 750mm out of the 1000mm total Y length.
Attachment 27423
Attachment 27424
Attachment 27425
For my Z axis, I'm planning to make this 350mm tall with 350mm rails and 265mm ballscrew.
I think I'm ready for a quote on linear components - would appreciate if someone could take a quick look and advise if there are any glaring issues?
These are sets from BST automation e.g https://www.aliexpress.com/item/3288...35f43557qd67J5
Ballscrew sets to include ballnut and mount, BK/BF supports and coupler.
2 set 1610 ballscrews X @ 965mm long
1 set 1610 ballscrew Y @ 1000mm (With Pulley Machining)
1 set 1605 Z @ 265mm (With Pulley Machining)
X rail set 2 x 1000mm rail and 4 x Hiwin 20mm Flanged Carriages
Y rail set 2 x 1000mm rail and 4 x Hiwin 20mm Carriages
Z rail set 1 x 350mm rails and 4 Hiwin 20mm Carriages
Thanks.
Ryan
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Re: Aluminium Profile Type Router - Initial questions
On the model, you show BOTH ends of the ball screws using BK bearings which are the fixed end bearings, which is the best way to fasten, BUT it's not the standard way. Usually, you have a fixed end BK bearing and a floating end BF bearing, so if you want BK on both ends you will need to tell Fred at BST otherwise they will machine them to standard.
Also mention you want the "F" Dimension which is the coupler portion at 25mm otherwise they will machine it 15mm.
Tell Fred you want the best BK/BF bearings not the cheap ones.
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
CNCRY
added a pulley based drive to the Y axis (borrowed from Andy's build log!)
I stole it from Joe, who I'm sure stole it from someone else. I'm reliably told it's called development!
Great progress Ryan, it's coming along.
Jazz's comments are spot on, and also your BK nearest the motor is back to front. Mention to Fred that your dimensions are for the screw part not total length else you'll end up short!
I'd recommend an F length of 30mm on Y and Z to give more room for those pulleys. Don't know if Jazz was saying 25 for the X couplings or the pulleys? Either way just gives more room to align that pulley.
I've noticed your gantry vertical plates are wider than the distance between carriages - the angle continues further than the carriage. Might be worth trimming that because it's essentially cosmetic in its current form and will be costing you when you order the plate.
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
JAZZCNC
On the model, you show BOTH ends of the ball screws using BK bearings which are the fixed end bearings, which is the best way to fasten, BUT it's not the standard way. Usually, you have a fixed end BK bearing and a floating end BF bearing, so if you want BK on both ends you will need to tell Fred at BST otherwise they will machine them to standard.
Also mention you want the "F" Dimension which is the coupler portion at 25mm otherwise they will machine it 15mm.
Tell Fred you want the best BK/BF bearings not the cheap ones.
Thanks Jazz - the BK bearings in the image were more just to guide placement and I'd just been copying the same object in fusion 360 rather then using the BF, but I do intend to do it the standard way.
OK - will request a bearing upgrade too. As mentioned in another thread, no idea if BST are shipping out at the moment, so will check on that. Just being impatient to start building something:)
Does the design overall look OK? It's heavily copied of course with a few tweaks!
I do intend to take up your kind phone offer soon - I think electronics will be a Major learning curve so have many questions!
Ryan
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Re: Aluminium Profile Type Router - Initial questions
Just a (genuine) question - have you considered belt-drive on the X as well as Y?, for me workshop space is a critical issue and being able to rotate the motors 180 degrees into the frame of the router would be a design goal if only to reduce the depth of the machine as it sits on the bench. If that's not an issue for you then ignore.
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
AndyUK
Hah! Yes, "Unless you're going down the linuxCNC route in which case I have no idea" :P
Reading it back it sounds like I'm saying don't use ethernet with LinuxCNC - it was meant as an "if you're using LinuxCNC there may be more appropriate options like onboard PCI cards".
I have a mesa PCI card I don't use at the moment but there is a rare problem with MESA PCI cards when installed in some machines will not boot.
I traced this to a PSU issue, I swapped 3 motherboards into that case before I realised it was the PSU that wasn't letting it boot. The Mesa people told me it happens in 1 in 100 machines.
As soon as I swapped the PSU it booted fine but I had to move the machine so I bought a standalone controller and put it on a catering table with wheels.
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
Doddy
Just a (genuine) question - have you considered belt-drive on the X as well as Y?, for me workshop space is a critical issue and being able to rotate the motors 180 degrees into the frame of the router would be a design goal if only to reduce the depth of the machine as it sits on the bench. If that's not an issue for you then ignore.
Hi Doddy, I considered this earlier but as the gantry is going to extend back on the X axis, beyond the cutting bed size anyway, then the motors don't add to the footprint, and slightly simpler to connect direct. It's on a workbench which is 120cm square, so gives me about 20cm for the motors/wiring etc!
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
AndyUK
I stole it from Joe, who I'm sure stole it from someone else. I'm reliably told it's called development!
Great progress Ryan, it's coming along.
Jazz's comments are spot on, and also your BK nearest the motor is back to front. Mention to Fred that your dimensions are for the screw part not total length else you'll end up short!
I'd recommend an F length of 30mm on Y and Z to give more room for those pulleys. Don't know if Jazz was saying 25 for the X couplings or the pulleys? Either way just gives more room to align that pulley.
I've noticed your gantry vertical plates are wider than the distance between carriages - the angle continues further than the carriage. Might be worth trimming that because it's essentially cosmetic in its current form and will be costing you when you order the plate.
Thanks Andy - feels like the design is almost there now, drawing in CAD certainly makes things easier to tweak/measure and figure out what should work.
Yes good shout on the gantry - I've reduced the width slightly (50mm approx) so it can be cut from a smaller piece of aluminium.
Just waiting to hear from Fred @ BST , so thinking about how I'll actually machine the pieces now.
Have you found printing 1:1 and sticking to the piece worked well? Also what contact adhesive did you use there?
I've bought some centre drills / counterbores to test out . Also thinking to get a metal cutting blade for the large wood bandsaw to cut the angle. That or a blade in mitre saw but feels a bandsaw would cope more..
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
CNCRY
Have you found printing 1:1 and sticking to the piece worked well? Also what contact adhesive did you use there?
Yeah it was a low-tech solution that worked quite well. Can get messy though, recommend some cellulose thinners and a rag on standby to wipe the other edges of the piece you're spraying, and obviously do it on a waste surface like cardboard. I got the wife to cut the printed bits out - shes a little bit more artsy and careful with a pair of scissors. It was then mainly a case of alignment as you put it on, trying to get a straight edge aligned with the edge of the metal. We found spraying half then putting on roughly worked well as you had a couple of seconds to adjust the paper slightly. Then fold over and spray the other half, and then flatten out.
Used Evostick Impact spray, but I'm sure any contact adhesive would do the job. This one is a bit costly, I probably nicked it from the in-laws....
https://www.amazon.co.uk/Impact-Mult.../dp/B0095RFILA
Helped a lot with the marking out. I used one of those push down centre punches, but others have used optical ones which look really good.
When you're finished drilling on them, get some lighter fluid to help remove the paper and contact adhesive. That was a nasty job... Then shine with scotch-brite.
Quote:
Originally Posted by
CNCRY
I've bought some centre drills / counterbores to test out . Also thinking to get a metal cutting blade for the large wood bandsaw to cut the angle. That or a blade in mitre saw but feels a bandsaw would cope more..
I love the counterbores I got. Great little tools. Centre drills didn't really work for me, I just ended up starting everything with a 2.5mm.
I used a crappy old table top wood band saw, and it worked okay. Just get a decent blade. I remember learning that you want approximately three teeth in contact, and I was cutting 10mm and 20mm Ali, so I went with approx 5mm pitch blade. Slow but steady, lots of cutting fluid.
However, I only used that for un-important edges. I got Aluminium warehouse to do the main cutting to size and just cut pieces in two where they had to be ordered as one piece due to minimum piece sizes. Where I had to cut a piece that mattered, I'd use Aluminium warehouse's edge as the mating side. That way all the mating surfaces have square(er) edges - the bandsaw cut edges needed a fair bit of sanding afterwards!
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2 Attachment(s)
Re: Aluminium Profile Type Router - Initial questions
So the build has officially started - I should probably convert this to a Build log if that's possible!
Attachment 27460
So the profile was joined using the self tapping M12 core screws, where the head slots into the 10mm profile slots and a hole is drilled though the profile to allow the T50 key to be inserted and tightened. This worked OK but I managed to almost break my wrist using a cordless drill and even a (cheap) impact driver struggled! Got there in the end and re-enforced with brackets.
I don't have any precision measuring tools at this point, but using the digital angle measure is 90.0 degrees on all angles and to 1mm across all dimensions.
Issue #1 - In my haste to add an extra piece of profile to my order (to have an L shaped gantry profile) the 2 profiles have different slot spacing. As far as I can tell the main issue is joining them. If these are joined simply by using the side gantry plates and socket head bolts to hold the pieces in contact is that a terrible idea? Could it be enhanced with some strong adhesive between the pieces to compensate. Really wan't to avoid wasting money on the extrusion if I can help it.. Any ideas?
Attachment 27461
I've also placed the order with BST Automation - Thanks for the recommendations. All smooth so far, Fred seems very responsive and helpful. There are expected delays due to the coronavirus but it sounds like production is just slightly slower then usual.
Only linear motion components so far - 1610 ballscrews and 1605 for Z. 20mm Linear rails and Carriages. Flanged Type for X axis for stability as I'm using a wide plate.
For the blocks which will mount to carriages - Is Ecocast type aluminium recommended here? Quite pricey for 50mm thick block so want to be sure it's worth using this.
Also thinking of what you mentioned Jazz - adjustability. Would slightly oversize holes be the usual way to achieve this?
On electronics - I'm considering Hybrid steppers now, certainly on X due to the dual X motors and potential stalling. Any recommendations on models here?
Thanks!
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
CNCRY
Attachment 27460
Issue #1 - In my haste to add an extra piece of profile to my order (to have an L shaped gantry profile) the 2 profiles have different slot spacing.
Is the bottom section a different Series? They both should be the same...ie Series 45( 45 mm between slots )?
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
Sterob
Is the bottom section a different Series? They both should be the same...ie Series 45( 45 mm between slots )?
Hi Stereob - yes correct, it's a different series. I hadn't realized until too late:( Hence seeing what I can do as a workaround..
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
CNCRY
If these are joined simply by using the side gantry plates and socket head bolts to hold the pieces in contact is that a terrible idea? Could it be enhanced with some strong adhesive between the pieces to compensate. Really wan't to avoid wasting money on the extrusion if I can help it.. Any ideas?
It's not the best of ways but if you bolt the profiles together along there length as well as the ends it should be ok. Obviously, because the slots don't line up you won't be able to use the slots to lock together but you should be able to drill and tap them together from underneath with a few bolts.
Don't use adhesive.!!
Quote:
Originally Posted by
CNCRY
For the blocks which will mount to carriages - Is Ecocast type aluminium recommended here? Quite pricey for 50mm thick block so want to be sure it's worth using this.
Cast plate isn't required but the plates must perfectly flat with parallel faces and exactly same thickness on both sides of machine. Rolled plate isn't flat or with parallel faces so unless you machine it flat and parallel then ground plate is your only choice if you want it right. Why 50mm thick.?
Quote:
Originally Posted by
CNCRY
Also thinking of what you mentioned Jazz - adjustability. Would slightly oversize holes be the usual way to achieve this?
Try to keep the holes to correct size if possible. Only make oversize if needed.
When I say adjustability I mean don't machine plates with slots etc that lock things together unless the whole machine is built this way and on an accurate machine. Adding plates or brackets that allow adjustability is always a good idea. When making plates etc then adding slots rather than holes can help in some places but depends on machine design.
One of my methods is to use slots to allow adjustabilty then when it's all setup I'll lock it in place using tappered holes and pins.
Quote:
Originally Posted by
CNCRY
On electronics - I'm considering Hybrid steppers now, certainly on X due to the dual X motors and potential stalling. Any recommendations on models here?
Wouldn't use anything else. These work well and allow AC or DC with voltages upto 70Vac or 100Vdc. This means you'll get good speed and with 5.5Nm you've plenty of power.
If you go for the lower powered motors just check the drives Max voltage because a lot of them are 50Vdc Max which will limit your speed.
https://www.aliexpress.com/item/3279...44bf3421SaYv5O
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1 Attachment(s)
Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
JAZZCNC
It's not the best of ways but if you bolt the profiles together along there length as well as the ends it should be ok. Obviously, because the slots don't line up you won't be able to use the slots to lock together but you should be able to drill and tap them together from underneath with a few bolts.
Don't use adhesive.!!
Cast plate isn't required but the plates must perfectly flat with parallel faces and exactly same thickness on both sides of machine. Rolled plate isn't flat or with parallel faces so unless you machine it flat and parallel then ground plate is your only choice if you want it right. Why 50mm thick.?
Try to keep the holes to correct size if possible. Only make oversize if needed.
When I say adjustability I mean don't machine plates with slots etc that lock things together unless the whole machine is built this way and on an accurate machine. Adding plates or brackets that allow adjustability is always a good idea. When making plates etc then adding slots rather than holes can help in some places but depends on machine design.
One of my methods is to use slots to allow adjustabilty then when it's all setup I'll lock it in place using tappered holes and pins.
Wouldn't use anything else. These work well and allow AC or DC with voltages upto 70Vac or 100Vdc. This means you'll get good speed and with 5.5Nm you've plenty of power.
If you go for the lower powered motors just check the drives Max voltage because a lot of them are 50Vdc Max which will limit your speed.
https://www.aliexpress.com/item/3279...44bf3421SaYv5O
I did some more thinking on 2 profiles with different spacing - as the 2 do not need to align on the face in the design, I can offset the top piece by 5mm so at least the front slot is in line, then bolt/tap the rear.
OK great - I'l either go for Ecocast or see if I can get it milled. Its 50mm thick as the block is intended to add some Z clearance for the gantry. Without it clearance is only about 100mm, so takes it upto 150mm .
Attachment 27466
Hybrid Steppers are slightly more reasonable price then I had expected Vs standard steppers. Looks like the LC60H2102 (4.5Nm) and LC60H2112 (4.8Nm) both also support 100VDC with the same LCDA86 Driver, although strangely are twice the price as the 5.5Nm from what I can see!
Would the 5.5Nm be overkill on the Z axis ?
I noticed the 5.5Nm has a 35mm shaft and keyway, which should help with pulley mounting. How does that work with direct coupling though, a keyway and standard shaft coupler?
Thanks
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1 Attachment(s)
Re: Aluminium Profile Type Router - Initial questions
700 x 500 x 250mm steel cabinet arrived today from TLC. Very solid and heavy @ 20kg. - hopefully everything will fit in based on previous builds on here! I see Andy had 800x600 which had a little space spare.
While I wait on the linear motion parts from BST - electronics are being planned, really steep learning curve here for me and hoping I can figure it all out with some of your help.
With the LCDA86 driver Jazz recommended, what voltage would be ideal. Its up to 100Vdc and I see a few people have used 68V - so would give some margin but would that be at expense of too much power?
LC60H2112 is listed as 5.6A current, so with 4 motors do I need 22.4A x 68V = 1523VA PSU? Sounds huge.
I'm trying to take each component in turn and map out the connections - first the driver to AXXB-E. Except for ALM I can't figure out which other terminals need to be connected if at all ? For example ENA+, Pend, and the Encoder E* ones.
AXXB manual refers to just Step and Dir.
Attachment 27524
Edit..Just realised VCC/GND wrong colours on that IMG..
Thanks
Ryan
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
CNCRY
700 x 500 x 250mm steel cabinet arrived today from TLC. Very solid and heavy @ 20kg. - hopefully everything will fit in based on previous builds on here! I see Andy had 800x600 which had a little space spare.
Yeah you'll be fine :) 800x600x300 was overkill. I have no idea how Joe filled 800x800x300.
Quote:
Originally Posted by
CNCRY
I'm trying to take each component in turn and map out the connections - first the driver to AXXB-E. Except for ALM I can't figure out which other terminals need to be connected if at all ? For example ENA+, Pend, and the Encoder E* ones.
AXXB manual refers to just Step and Dir.
Good plan. Generally speakings, Step and Dir are the two required ones.
Enable turns the drive output on or off to prevent the motor turning without killing power to the drive, usually when left disconnected the motor is just enabled by default.
Alarm should output a fault signal to the AXXB if something goes wrong. Best to have it connected somehow if you can, but there are a lot of options about exactly how you wire it up. E.g. it could estop the system on fault, or just tell the AXXB to pause.
Pend appears to be 'positioning completion signal', encoder and the motor phases should be the wires from your motor.
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
CNCRY
With the LCDA86 driver Jazz recommended, what voltage would be ideal. Its up to 100Vdc and I see a few people have used 68V - so would give some margin but would that be at expense of too much power?
LC60H2112 is listed as 5.6A current, so with 4 motors do I need 22.4A x 68V = 1523VA PSU? Sounds huge.
You don't need 22.4a you only need approx. 60% of total current draw because of how the drives work using PWM etc which I won't get into. Also you'll rarely max out all motors so got little more leigh way in use.
I would use AC and do away with the need to rectify and Caps etc required for DC. This is what I would use with those drives wired AC. Wire the secondaries in parallel and you'll end up with approx. 11a which isn't quite 60% but still more than enough.
https://airlinktransformers.com/prod...ange-cm0750265
Quote:
Originally Posted by
CNCRY
I'm trying to take each component in turn and map out the connections - first the driver to AXXB-E. Except for ALM I can't figure out which other terminals need to be connected if at all ? For example ENA+, Pend, and the Encoder E* ones.
AXXB manual refers to just Step and Dir.
Start simple, if your not used to wiring things like this don't try and wire it all in one go it will just blow your mind. Start with basics first and do it in stages.
I would start by setting up the main latching E-stop circuit and getting movement just with Step & Dir. Forget, enables and alarms at first they can be added later.
Next wire in Home/limit switches. This then gives you the basics or a working machine.
Now you can start adding other features like Alarms, enables etc and controlling any external devices using outputs etc like spindle control.
My favourite saying is "Treat it like eating an elephant, one bite at a time."
Edit: With the cabinet don't stress out over this either, concentrate on layout and wire routing , the main thing is to keep low voltage signal wires away from higher voltage wires as much as possible and make sure you use Star grounding. If your using a VFD and thinking to put in cabinet just pay close attention to where the main spindle cable goes, I'd also suggest you don't put it near the main controller.
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1 Attachment(s)
Re: Aluminium Profile Type Router - Initial questions
OK so I've listened to the start simple advise and taking each part at a time! So plan is to sort out the cabinet layout, power distribution, e-stop and switches first, then add controller and drives once the machine is actually built.
That way the low(er) cost and less complex items can be fitted now and drivers / controller / home and limits / alarms / faults to be added once the machine is built, and finally VFD and spindle.
I have this for the cabinet layout - does it look OK or any issues?
Attachment 27535
I'm planning to buy these - could someone confirm they are OK choices, especially the contactor! Looks like it is DC
https://www.rapidonline.com/mean-wel...cy-psu-85-5684
https://www.rapidonline.com/schneide...tactor-66-1939
Couple other questions from the never ending list:)
- Do I need to Fuse the drivers? They have overcurrent/voltage but I notice some people have?
- Are EMI filters needed with decent star grounding? I'm planning to add the EMI filter option on the transformer.
Possibly one day I can answer some questions:) On a side note, looks like quite a few builds stall or just about complete and then people disappear from the forum, big thanks to those who stick around to keep helping others.
Ryan
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Re: Aluminium Profile Type Router - Initial questions
Personal view - there is little point in providing fuses for the drivers. A fuse will never "protect" a driver as the semiconductors in the driver will let out the magic smoke well before the fuse can react in the event of a major fault (and I'm thinking short-circuited motor wires, for example). If the built-in protection doesn't work, then it's already too late for a fuse. Where a fuse might help is in the output of the driver power supply, or maybe in the input to it. In the event of a fault in a driver that causes a high current draw, this will protect the power supply. In fact, the only electrical fault that has happened in my own control box was an internal short in the toroidal transformer which took out the fuse on the input (mains) side - fortunately. Generally speaking, fuses do not "protect" equipment - they help stop wiring, etc, bursting into flames when something has already failed. As I say, this is a personal view and others are paranoid about fuses everywhere. Be interesting to hear if these fuses have ever "saved" anything!
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
Neale
Personal view - Be interesting to hear if these fuses have ever "saved" anything!
My personal view is that it's stupid not to fit a fuse just to save a few pence. Why risk an £80 drive for the sake of an 80P fuse to protect from the unknown.!.
To answer the question have they ever "saved anything" then it's a BIG FAT YES I've had many cases where things like loose wires have shorted or been rubbed through etc. The point being your not actually always trying to protect the device but the system as a whole from unforeseen circumstances so spending a few quid more for fuses to protect valuable parts of the control box is a No brainer to me.
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
Neale
Be interesting to hear if these fuses have ever "saved" anything!
I've already buried the spindle in the work a couple of times, both times have 'gently' blown the VFD fuse before any damage was caused elsewhere. The power loss to the VFD also causes a fault on the controller so stops the motors, which is kinda nice.
Quote:
Originally Posted by
CNCRY
I have this for the cabinet layout - does it look OK or any issues?
Three things spring to mind:
- VFD Spacing against internal walls. Read the manual for how far it should be away to allow adequate air flow.
- I'd keep earth near Line and Neutral, thats where it comes in after all, and a lot of the big ticket earthing items will be mains voltage.
- You've made a good start trying to separate voltage levels, but the 5V PSU should be at the low voltage end of the cabinet rather than its current position near 65V DC.
- Think about air flow through the cabinet - At the moment your drivers will get decent flow, but the VFD won't. What direction are those fans? I orientated my drivers to allow maximal air flow through their heatsinks, at the moment your heat sinks are at 90 degrees to the air flow.
Will it work in its current state? Sure. None of these things are big issues, just minor points.
Quote:
Originally Posted by
CNCRY
You've gone for the high efficiency and expensive one, is there any reason? This is the alternative to save £10.
https://www.rapidonline.com/mean-wel...il-psu-85-5678
Contactor seems okay.
Quote:
Originally Posted by
CNCRY
Couple other questions from the never ending list:)
- Do I need to Fuse the drivers? They have overcurrent/voltage but I notice some people have?
- Are EMI filters needed with decent star grounding? I'm planning to add the EMI filter option on the transformer.
Extra fuses won't hurt.
The advice I found at the time was that some people needed to plug the VFD in at the other end of the workshop to reduce the noise back from it, and I wanted to be able to power everything from the same socket. The EMI filters I used were about £5 each, and although I have no idea if they're needed or not, they do allow me to operate without noise issues with everything running off the same 13A socket.
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Re: Aluminium Profile Type Router - Initial questions
Aha, the old benefit-risk balance.
The fuse is cheap, however, the probability of it protecting a driver with a shorted output is uncertain - I can imagine a driver without overcurrent protection popping before the fuse depending on how much you've pissed off your local deity.
The real purpose of the fuse is as a safety device to cover the fault condition and something in the high-hundreds VA rated transformers making something go bang. Or Pfftt! Or Whoosh!. Or whatever sound a decent arc makes... something like Pzzzzat! It could save the transformer as well which could be a good part of a hundred quid worth. And if it avoids a fire, then it might save on the insurance excess.
A fuse on the drivers can't be considered a bad thing but don't rely on it protecting the drivers.
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Re: Aluminium Profile Type Router - Initial questions
Quote:
Originally Posted by
CNCRY
I have this for the cabinet layout - does it look OK or any issues?
Attachment 27535
You need to think about how the wires run and trunking. how you have it there would be awkward for running wires etc.
I would move the drives away from the Transformer and bring the DC PSU and MCB's etc down near the Transformer so all together in one area. If you have room even bring the VFD into the same area, this way all the high voltage stuff is together.
I would have the drives and controller close together to keep Signal wire runs short as possible. Separate the high power stuff from the Low voltage stuff by placing high and low in the case with Terminal blocks and Relays etc along with trunking between them, essentially dividing the case into 3 areas.
This doesn't matter if it's separated horizontally or vertically, for instance, I often run the drives along the sides of the case vertically as it's easier to wire them. On the opposite side, I will place VFD at the top and PSU, etc below. In the middle will be Terminals and Controller.
Also, I would think about having 2 fans in the case to create a positive pressure in the case to push hot air out.
Edit: Noticed that you have a Pilz relay shown, you don't actually need a safety relay. A normal Relay will work just as well and save you a lot of money.
Lastly, looking at your drawing the scale looks wrong on the parts shown so be very careful when planning out the box because it's SO EASY to run out of room. Often the case will look massive when empty but it quickly fills up. Also if you haven't got the box to measure from then allow a little extra because things like hinges or Earth clamps etc can rob precious space and easily screw up layout plans.
Also if not got a case and solely planning layout in Cad or on paper then I'd try to get exact dimensions of any components because again can soon run out of space and no matter what you do or how you twist things around it just won't fit.!
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1 Attachment(s)
Re: Aluminium Profile Type Router - Initial questions
Attachment 27555
Attempt number 2 - tried to separate Low/High voltage more and incorporate some other suggestions. Airflow intake at the bottom and out at the top, by VFD fan.
I checked the scale and believe its correct - cabinet is 700mm x 500mm . Although the DIN rail items are NOT to scale yet, the DIN rail is. I'll take some photos when parts physically arrive..
I think the conclusion is that fuses are v unlikely to be a negative addition, and probably positive, I'll add these between transformer output and Drivers AC input - probably 5/6A.
I did buy a PNOZ already as I made an ebay offer on one new much below "retail" price and got unexpectedly got accepted.
Andy - yes good shout on 24V PSU, just chose wrong one.
Think I'll need to add a fire extinguisher to the list too before I get started:)