Aluminium Profile Type Router - Initial questions

[CNCRY]

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.



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?



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

[AndyUK]

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.

[CNCRY]

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

[CNCRY]

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.







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

[CNCRY]

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.





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

[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.

[CNCRY]

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

[AndyUK]

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.

[CNCRY]

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..