I've built this machine 100 different times in my head!!!

Finally I get the courage to join the forum and start making threads after 2 yeas of first stumbling onto it. When I first got the craze to build my own router, I got so wrapped around the idea I was going to build this incredible machine, which most of my friends don't even know what it is, I started ordering parts without any plans drawn.

So my list of components I have are,
3 sy60sth88-3008bf motors
3 pm752 drivers
breakout board
20mm supported round rail for the x and y axis at 1200mm and 800mm respectively
15mm profiled rail and slides for the z axis at 550mm long
4 1605 ballscrews with nuts and mounts
a 50v minebea psu from ebay, but will eventually build my own.

All this was bought 2 years ago from Zapp and Chai, so now I have to reverse engineer my router to fit these items. I have made some detailed drawings of how I would like my machine to look, but would like some input on a few things.

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Ok, as you can see I've been trawling all the build logs and tried to incorporate what I think would be best for my build.

The gantry sides and whole z axis will be made from Ecocast 20mm x 200mm wide ali plate.
The rear plate to the gantry will be 10mm thick which I hope will be sufficient.
The Z axis will have rails on the front plate and slides in the back plate.
All axis will be connected with screws using pulleys and currently at a 1:1 ratio just to get the machine moving.
The frame, which is very similar to Jonathan's, will be made from 50mm steel box section and 50mm x 100mm for the top supporting rail. I'm planing for some adjustability so will be welding the whole bottom section but will use plates and bolts for the top RHS on to which the 20mm suported x axis rails will be resting on. I won't be using any welding on this top section to avoid warping. The actual cutting bed will be height adjustable too.

A few questions I have will be described with illustrations.


Attachment 6301Attachment 6302

The Z axis I have uses 15mm NSK profiled rails and slides. The problem here is that the total height from the bottom of the rail to the top of the slide is 16mm. The ballscrew mounts which is in between the 2 plates is 43mm thick, so I have to add 30mm of material in between the plates. I would like to know is it best to have this extra spacer added to the rails side, or the slides side. Both variations are shown in the top drawings.

Next:
Attachment 6303

This type of x axis ball nut mount looks the easiest and neatest from my side, but is it strong enough for pushing the whole gantry. It is made using 20mm plate and has 2 functions, as a nut mount and also to hole the gantry side square to the bearing plate.

Lastly:
Attachment 6304

I will be using 50mm ali boxing to support the y axis rails onto, but I'm unsure if the wall thickness is enough to drill, tap and hold screws from the top, and also from the back for the 10mm plate. This box section will be held onto the gantry side plates using registering blocks screwed onto the gantry sides and then a threaded rod right the way through the ali box section from gantry side to gantry side. As I've drawn above I could if its very necessary, make a strip of 10mm ali plate into a nut plate, if I can call it that. It will have holes drilled and tapped in the exact position to match the holes on the supported round rails. This way I could make the holes in the ali box section slightly larger and have some adjustability to get the rails aligned with each other.

Thanks for being patient and reading this long boring thread.

Adil

Wow, at last someone has bothered to read build logs and think about it before posting :thumsup:

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Originally Posted by Iwant1

The frame, which is very similar to Jonathan's, will be made from 50mm steel box section and 50mm x 100mm for the top supporting rail.

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What wall thickness? If you stick with 3mm, maybe 3.6mm, it's much easier to weld. Just for reference mine is mainly 60x60x3, 100x60x3.6 (x-rails) and a small amount of 50x50x3mm. If you add some pieces in the corners of the frame at 45° it will significantly increase the rigidity of the frame. I never got round to adding them on mine, although they are on the original drawing. It's the sort of thing you can add when the rest is welded to use up any left over box section.

With regards to the Z-axis rail mounting - neither of those methods is ideal. If you had to pick one I'd put the rails on blocks as that would help stop the Z-axis plate bending, but they would have to be machined accurately - not just any old flat bar. However I'd consider that a last resort since it is important, particularly withnot having profile rails on Y, to get the cutter as close to the Y-axis bearings, when measured parallel to X (the 'overhang'), as you can. Since the Y-axis bearing blocks have a finite stiffness, when a force is applied to the cutter parallel to Y the tool will deflect and this deflection will be proportional to the aforementioned distance, therefore you should minimise it as it will directly increase rigidity.
As you're using standard BK/BF bearing blocks this presents a problem, since clearly they will collide with the Z-axis plate if the spacing is reduced. Options:
1) Make cutouts in both of the 20mm plates which the bearing and ballnut blocks 'sink' into, to effectively reduce their centre height.
2) Use a longer ballscrew and mount it to the Z-axis plate (like on mine), that way the bearing blocks wont be over the other plate. Still need cutout for ballnut.
3) Make lower profile bearing/ballnut mounts, then less deep cutouts are required.

Problem is all of these options are easiest with a milling machine, or require outsourcing but to me it would definitely be worth it.

The ballnut mount looks weak to me since it's so long. The easiest solution is to move the ballscrews up, but no doubt you didn't do that because the ballscrews aren't long enough to mount at the most convenient point. You could make the ballnut mount stronger, but even then there's quite a distance (measured vertically) between the X-ballnut and rail, which for the same reason as for Y/Z it's best to minimise. I would be inclined to raise the ballscrew so it is in line with the X-axis rails and add an aluminium plate to support the non driven end, preferably linking on to the far vertical support. The strength of the non-driven end bearing mount isn't critical as it's (roughly) only there to stop the screw whipping, so there's not much force on it.

I bolted my Y-axis rails to 80x80x3mm aluminium box section. The bolts are strong enough, but in my case the box section is a weak point as there is only one. You can get the necessary adjustment on the rails for them to run smoothly by drilling the holes in the rails slightly bigger to give the bolts a bit of clearance. It would be nice to use a greater wall thickness just from a strength point of view.

Thanks for the suggestions Jonathan. I've redrawn the x axis screw so it is as close to the supported rail as possible. This has bought the ball nut mount up by 60cm.

Attachment 6305Attachment 6306

Regards the z axis. I had no idea I had to consider the height of profiled slides when I bought them of eBay. Lesson learnt, and if as you say I machine about 10mm grove out of both z axis plates, I still need 10mm. Say I grove out 10mm from the front plate, then sink the ball nut even more, up to a point where the screw shaft just clears the front plate, then I might just get away with that last ten. I'll draw this later to see if it is feasible.

I would definitely consider outsourcing to one of you guys to machine these plates as it will make a much sleeker z axis and also bring the spindle cutting point to within the x axis bearing blocks.

You should consider incorporating adjustment of one of the X-axis ballnut mounts to gain better alignment of the ballscrew. Currently you're relying on the accuracy of the frame, rail position and all sorts for the distance between the rail and the ballscrew to remain constant. In reality the tolerances on all these build up, so it's easiest to make sure at least one of the bearing mounts (clearly the non-driven end is easiest) position is adjustable in the Y-Z plane to ensure you can align it accurately. If not you risk the mechanism binding towards each end which will put a large force on the ballscrew/nut...

On my Z-axis I currently have 520mm long 20mm NSK rails, so the additional height of those helped. If you go up to 25mm plate for one of the plates on the Z-axis that might help to get the required pocket depth without sacrificing strength. Using that strategy I recently made a Z-axis using 25mm profile rails with only 2mm clearance between the plates. Also if you get the Z-axis parts machined there's not really any need to use the more expensive tooling plate - I would mill the surfaces for the rails and blocks to get them flat and in the same plane.

I was just thinking about that adjustment last night. I was going to slide the gantry to the driven end of the x axis, locate the ball screw bearing block there, then slide the gantry to the non driven end and get the position for that screw bearing block. Suppose great minds think alike lol.

Great advice about getting 25mm plate. Does that mean it would be safe to remove 15mm of material? If I don't need EcoCast then what would be suitable 6082 plate, 5083 plate or 6082 flat bar. Also how accurate does the 10mm plate that goes behind the gantry have to be? sorry for so many questions.

I basically was reading in lots of forums that 15mm profile rails would be plenty strong for all axis, but never thought 20/25mm would be better for filling spaces between z plates.

Originally I was going to make the z axis the way I'v drawn, then use a working machine to mill out what we are discussing for a version 2 machine. Thanks for offering, I will pm you about your pricing once I've re drawn it.

Like jonathan it's nice to see someone who's actually done the leg work and payed attention. . 10/10. . Big respect. .:thumsup:

Agree with Jonathan on every thing he's said except not using the Ecocast.! Even thou you will machine the bearing mounts etc unless you surface and make parallel both surfaces your still going to have troubles and in-accurecy. The problem comes from the cheaper plate not being uniform thickness so you can't be sure it's the same thickness (Or flat) all along it's length. This means buying much thicker than needed so it can be surfaced and still have the required thickness to be strong.
I used to do just this but since the Ecocast has been easily available in small qty then I don't bother any more and it cuts out some of the work involved and makes things that bit easier.

To be honest the 20mm plate is still fine regards strength even with the neccesary slots cut, I've made several with 19mm 6082 and slots etc and they are more than strong enough for even the most demanding jobs.! (Within reason) See pics of what you may have seen before just not striped down like these.?
(obviously more thickness will be stronger but not 20mm gets the job done.!!)

The only other point I will mention is the belt setup and the lack of protection from chips etc.!!
You probably know my machine use's this setup and I'm guilty of not covering the belts and while it's never been a problem, other than grabbing my teashirt a few times and trying to eat me, I would still advise you to cover them up before using the machine.! . . .I'm pretty sure the constant pounding from chips etc has or will shorten the belts life so worth doing before using the machine otherwise like me you'll never do it after machines put to work.!!

Anyway great work and can't wait to see it turn into reality. . .:yahoo:

Redrawn the z axis with new 25mm plates for the rear and front. Also included registers for the NSK rails and slides although they are only 1mm. It is a very tight fit and looks much sleeker now at only 64mm depth. I suppose If I had to then I could sink the bk/bf blocks a few mm into the rear plate, just where the blocks go. Its not easy to show but the ball nut's flange head sticks into the front plate by a few mm, which could be a good thing if the hole is machined accurately.

The spindle cutter head has now moved 30mm towards the y axis and now rests between the x axis bearing blocks. Pictures showing the new design and also how far the z extension could be dropped. Its around 250mm, not that I would need that much, but the rails are long so might as well use them. I try to put as many detailed pics up for all novices to see, as this is what I was looking for while doing my research. Hope it helps someone.

Adil

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Ermm.!! . . . . Been looking at this thinking don't seem quite right.??? . . . I'm sure it's correct because you've obviously taken lots of time over it but I'll ask anyway just in case.!!

The bearing/rail height seems low.? from the dimensions on the drawing it appears to be about 16mm this is very low even for 15mm profiled rails and surely can't be right.? Do you have the bearings set in pockets.?

Thanks for noticing how small my profiled rails are. I mentioned earlier in the thread I didn't realise that they came in such low profile dimension. I got them for £70 from ebay for two slides and 4 rails as 15mm width and 550mm length. I've attached some pics to show their dimensions with respect to the bk/bf blocks. This is why I'm in a pickle over using 25mm plates for the z axis with 15mm machines out from each.

Do you think I should sell them on and get slightly larger rails.

Quote:

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Originally Posted by Iwant1

I've attached some pics to show their dimensions with respect to the bk/bf blocks.

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As a novice who has never seen any of these components in the flesh so to speak, those dimensioned pics have really helped me and reminded me that I need to get a digital caliper... thanks Iwant1... I'm following your build with interest btw, and want one too!

Quote:

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Originally Posted by Iwant1

Do you think I should sell them on and get slightly larger rails.

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I wouldn't go that far but they certainly are not ideal in the respect they make the pockets deep.!!

There is one thing I'm not to sure about and it's hard to tell from the pics, is that they don't look like the 4 row type bearings.? This makes them that bit less ideal and less able to stand the strain that a Z axis will come under.!! If 2 row type then I think for a Z axis then yes I'd sell them and get 4 row type more suited and making the job a bit easier.!!

Having 4-row profile rails is an advantage over 2-row - twice the balls = twice the surface area in contact with the rails which should get better stiffness, in addition to factors usually mentioned. However 2-row is still in a different league compared to round rails, so unless you can sell them and get better rails for the same price I think there's other places the money would be better spent on. You've got long rails, so use that to your advantage as if you're prepared to sacrifice some travel you can space the bearing blocks out more to reduce the load on each, so long as the piece they are mounted on is stiff. I got 760mm rails for my Z-axis, so if I ever get round to making it I'll keep 400mm travel and have the bearings 360mm between ends, which is slightly extreme but the rails were cheap so why not.

Quote:

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Originally Posted by Iwant1

Lost of cnc machine parts are available in the SketchUp marketplace, which you get to from within SketchUp. All the rails, bearings, spindle, motors, ball nuts, etc are available.

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The standard part libraries can be helpful, but I tend to draw things myself so I can be confident it is correct. I guess if I used SketchUp I might think differently.

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Originally Posted by Jonathan

The standard part libraries can be helpful, but I tend to draw things myself so I can be confident it is correct. I guess if I used SketchUp I might think differently.

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Very true, many of the parts I used, such as the pulleys, timing belts, ball nuts, linear rails and slides were all over 50 times the size I needed and some not 100% right. I spent loads of time scaling the items as a whole and also separately in each axis so that they match what I had. The problem was in SketchUp, the scale function works as a percentage where as I wanted dimensions, so I had to resize, measure, resize again, measure again..... to fractions of mm's. Next time I'll make them up but then I suppose the same tedious task will be spent with my vernier calipers.

Regards the profiled rails, I think what I paid for these 'mini slides' was very good and I definitely won't be able to get larger ones for this price. I spent ages today trawling eBay for profile rails and carriages and found that I can get Thk and Nsk sets at similar length for around £150 with p&p. Problem is I had to constantly go to their manufacturer websites and check whether they got 2 or 4 rows of balls. Then you find out the balls also have 30,45, and 90 degree configurations. Plus I started mixing models like hgh, hgw, hsr, ssr, sr, lf, lu with the wrong manufactures.

I've seen Zapp is very reasonable with his Hiwin rails and carriages, which work out at £180 for a brand new set, hgh15ca and 500 rails, compared to £150 for similar spec second hand Thk/Nsk on eBay. I don't understand how there can only be £30 difference, are Hiwin a cheap brand compared to Thk and Nsk.

I'm also not sure what preload is suitable for my z axis, as gravity is always going to pull the carriages down especially when all components are connected to it. Does ZO, little preload, mean there is more play between rail and carriages then ZA, medium preload. I have no actual experience what any type of preload feels like, as I only have the second hand ones to go by, which you can blow from one side to the other.

Thanks
Adil

Personally i would use ZA pre load.
Also a heads up, Hiwin have just raised their prices by about 20%, so expect prices to go up by about 25% with most if not all distributors.

I'm trying to make the build as strong as I can or will ever need. There's no specific need for this router, just for fun. Many of my mates ask, 'what's the first thing you're going to make?' I tell them a plaque saying 'test cut', lol. There's no budget to it, just being wise with money. In the end I'm sure it will cost near £1500 once spindle, plate ali, steel tubing, pulleys and belts are factored in. So far Chai took £550 and Zapp took £250 for the electrics.

Time is always a problem as the family want some dad time in the evenings after work. Suppose I'll have to get my 2 and 4 year olds to help mix up my screws and loose my tools. Funny how all kids love work shops, so many things to play with.

Adil

Quote:

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Originally Posted by Iwant1

I spent ages today trawling eBay for profile rails and carriages and found that I can get Thk and Nsk sets at similar length for around £150 with p&p.

I've seen Zapp is very reasonable with his Hiwin rails and carriages, which work out at £180 for a brand new set, hgh15ca and 500 rails, compared to £150 for similar spec second hand Thk/Nsk on eBay. I don't understand how there can only be £30 difference, are Hiwin a cheap brand compared to Thk and Nsk.

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That's because you only spent 'today' looking, you have to be patient to get the good deals - bidding not buyitnow. Yes I know, I used to think it's annoying when people say things like that, but it's worked for me in the end.

Quote:

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Originally Posted by Iwant1

Does ZO, little preload, mean there is more play between rail and carriages then ZA, medium preload. I have no actual experience what any type of preload feels like, as I only have the second hand ones to go by, which you can blow from one side to the other.

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If you can blow the carriage along, or it drops if you hold the rail vertically, then the pre-load is zero (Z0). When there is preload there is no clearence (play) between the rail and carriages, in fact the clearance is negative so it's an interference. This means that when the carriage is slid on to the rail the bearings distort slightly, so there is a force between the bearings and the rail - hence the name preload.

I'd consider having zero, or very low, pre-load a much bigger issue than only two rows of balls. You've got both...

P.S. Noticed there's two discussions going on here, the machine and sketchup - I can separate them if you want?

Quote:

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Originally Posted by Jonathan

I'd consider having zero, or very low, pre-load a much bigger issue than only two rows of balls. You've got both...

P.S. Noticed there's two discussions going on here, the machine and sketchup - I can separate them if you want?

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Thanks for the insight Jonathan, seems as though I made a bad purchase with my profile rails and have decided to get new ones with medium preload and 4 rows of balls.

I think the sketchup discussions have come to an end, and now will be mostly about my build.

Quote:

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Originally Posted by Iwant1

Thanks for the insight Jonathan, seems as though I made a bad purchase with my profile rails and have decided to get new ones with medium preload and 4 rows of balls.

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Unless you're desperate to get this done, I hope 'new ones' doesn't mean brand new, not from eBay. You only really need to know which rails you have the day before the Z-axis is actually cut, so unless you're in a massive hurry until that time you can wait for something good on eBay.

Hello all,

I decided to do the version2 upgrade whilst v1 was still in the drawing stage. The main change was to go profile rails on all axis. I also changed the x axis steel rectangle box for 45x90mm ali extrusion as it looks simpler and more accurate to fix the profile rails onto. Same goes for the y axis ali box section except its 45x45mm extrusion. There are two qualities to buy extrusion at, light and heavy. What do most people go with.

Anyways, here are some modified drawings. The first one shows the profile update and the x axis ball nut mount which now allows for adjustment. The middle pic shows how I intend on screwing the bk support block and z motor mount opposite each other. A screw will go from the bk side, through the z rear plate and screw into the motor mount. Hope that is strong enough. Last picture shows how the z plates will be machined to make registers for profile rails and carriages and also allow space for moving parts.

Attachment 6370Attachment 6371Attachment 6372

Thanks for looking
Adil

Definatly use the 'heavy' extrusion if you can afford it. What profile rails are those and what size...hiwin?

Quote:

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Originally Posted by Iwant1

A screw will go from the bk side, through the z rear plate and screw into the motor mount. Hope that is strong enough.

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It probably would be strong enough, but it would be good to have a second support for the motor mount, like this one I made earlier:

Attachment 6373Attachment 6374

Much more important though is you need some method to tension the belt. The easiest way is to instead of having simple holes in the motor mount, make them slots so you can pull the motor/belt tight then tighten the bolts - again like in the one above. This also allows different pulley sizes to be used without changing the belt, which could come in useful.

Edit: Just to add, moved sketchup discussion here as requested.

Quote:

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Originally Posted by Jonathan

This also allows different pulley sizes to be used without changing the belt, which could come in useful.

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Thanks Jonathan, good advice as I will be putting larger pulleys on the motor side. Now I can do it with the same belt.

Yep going for Hiwin, as I can't find any suppliers of new THK or NSK. I'm using 20mm profile rails and the carriages have 4 rows of balls.

I've redrawn the motor mount, but decided not to go with a full plate on the back of the z axis. Just extra weight for the gantry to carry. Can be easily added later if needed.

Attachment 6386

Quote:

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Originally Posted by Iwant1

Yep going for Hiwin, as I can't find any suppliers of new THK or NSK. I'm using 20mm profile rails and the carriages have 4 rows of balls.

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15mm rails will be plenty strong enough. The load ratings of 15mm are several times what the machine will require... considering you were happy with round rails just a few days ago, I don't think there's much point using bigger than 15mm since the difference in stiffness between 15mm and 20mm profile rails is tiny compared to the difference between profile rails and round rails. Many much larger industrial machines use 15mm rails.

Quote:

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Originally Posted by Iwant1

I've redrawn the motor mount, but decided not to go with a full plate on the back of the z axis. Just extra weight for the gantry to carry. Can be easily added later if needed.

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If you do add one it needn't be thick - 10mm would be fine as it's only to stop the joint between the plates that the Y and Z bearing blocks mount on bending.

Quote:

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Originally Posted by Jonathan

If you do add one it needn't be thick - 10mm would be fine as it's only to stop the joint between the plates that the Y and Z bearing blocks mount on bending.

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Know this is a bit late 3 weeks after posting but I've been asked for some input by Adil and was looking over the build again and spotted this comment.!!

Jonathan never have understood why you use this rear plate in the way you do because that rear plate on the back add's very little protection against the joint between Y axis bearing plate and Z axis rear plate bending in the vertical.?
The only forces that apply here are vertical force applied from one side and the overhang distance from the Y axis bearing plate to Z axis rear plate is nothing.? possibly few MM's. So the chances of that joint bending are zilch and if the forces were great enough to bend that then the rest of the frame and gantry are in big trouble and 99% sure something else would be bending/breaking much sooner.
Your design is an open ended box with very little strength in the vertical direction and if enough vertical force is applied at one side the other side will deflect in a similar manner.!

If you want to brace for that movement then plates on the side bolted into both plates would be much better and could be much thinner and still give far better bracing support than those backplates.? This back plate just add's weight and cost IMO for not enough gain and isn't required.!

The back plate is there because otherwise the Y-bearing mount plates are effectively cantilevered, hence in my opinion it's worth having something to reinforce these joints. However I agree that plates on the sides, as you suggest, would offer much better reinforcement, but this would increase the width of the Z-axis and loose some travel on Y, assuming the width of the Z-axis has already minimised. The plate certainly doesn't need to be the same thickness as the other parts, it was just convenient for the one in post #20 since I didn't have much of anything less than 20mm in stock, plus it was an easy way to support the motor mount.

Iwant1: How far are you with the design / build now?

Quote:

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Originally Posted by Jonathan

The back plate is there because otherwise the Y-bearing mount plates are effectively cantilevered,

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Not really much of a cantilever is it at 1 or 2mm and still your not supporting the cantilever but have created double cantilever ~(see-saw with bearings as pivot.!) with no bracing support.!!
Plate thickness doesn't matter could be 50mm or 5mm it's still adding very little vertical bracing support.? Plus it restricts the back side of the gantry so cable chain etc is more difficult to run.? . . . Like say IMO it's heavy, expensive, restrictive and unnecessary. . . Each to there own.!!!

Quote:

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Originally Posted by Jonathan

Iwant1: How far are you with the design / build now?

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Lots of changes have been made, its an ongoing process with every new thread on here, regarding motor drives and the strongest gantry designs. It gets so confusing. So far, I've managed to sell off my supported round rails and have already bought profiled rails for all axis, got a good price so went with 20mm. I also sold my 50v power supply and got a 2x24v toroidal coil from which I will build my 70v supply. And now I'm thinking about selling my pm752's for the digital am822's. I Know I know, I should have waited before I bought all the wrong components, but at the time, 2010, these were the most popular components. 2 years later I now want an even better machine than I originally thought of.

Anyway, I've also been busy buying all the electronics for my control cabinet. I will be using an old pc case, and filling it with goodies. Around £300 have been spent on all the electric bits, including screened cables, regular 16/0.2 cables, e-stops, limit and homing switches, relay gear, toriodal coil and electronics to rectify it, 12v and 24v psu's, small consumer unit, a selection of plugs and sockets, and the list goes on.

Chai a even sorted me out with a good price for a 2.2kw spindle and vfd, so I went and got some cooling components for this too. Mainly, a water pump with reservoir, double aluminium heat exchanger, 2 120mm pc fans and grills to go with the exchanger. Once these bit arrive, then I will see what size pvc hose I need.

I've been taking pic's of the control cabinet getting made and will post soon.

Adil

Quote:

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Originally Posted by Iwant1

... I've ....... bought profiled rails for all axis, got a good price so went with 20mm ........ limit and homing switches...

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I'm guessing that 20mm is kind of the norm for profile-rails and what Jazz for example has used on the majority of his machine pics?

How much space does one need to allow for limit switches?

Quote:

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Originally Posted by WandrinAndy

How much space does one need to allow for limit switches?

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Limit switches are quite small and can be put in most place, on the frame or moving parts like the gantry or z axis. I bought the regular small lever micro switches by Omron not the cheap unbranded ones.

But the homing switches, if you use good ones can be around 50mm x 50mm and 20mm thick, quite large. Again I went for Omron and got a good deal on ebay

Quote:

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Originally Posted by WandrinAndy

I'm guessing that 20mm is kind of the norm for profile-rails and what Jazz for example has used on the majority of his machine pics?

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Andy I only use 20mm because I get them for almost same money has 15mm so worth the few quid more. . . BUT they are massively over the top and 15mm would be far more than enough so use 15mm if you find some cheap.!

So, while away all the bits and pieces I ordered arrived behind me. It was like Christmas, opening all the parcels. I loved it.

Here are some pictures which I think will help others new cnc builders realise how many parts we need to buy.

The first picture is my control box layout inside of an old pc case. 12v, 24v and 70v psu are here along with drives, safety relays, discharge resister, BOB and fuse box.
Attachment 6802

My spindle and VFD were from Chai, unfortunately FedEX hit me with a 35 quid bill. I bought an er20 collet set, and full cooling setup consisting of double ali radiator, 2 fans, and a pump with reservoir. Just need to buy hoses and adapters. It was a great feeling powering the spindle for the first time.
Attachment 6803

This picture shows all the other components like switches, connectors, wiring, e-stops and lever connector blocks. Just forgot to put the cy screened cable in this photo.
Attachment 6804

Close up of switches and plugs. Andy, here you can see the difference in size between my 3 homing switches and 6 regular micro limit switches. The green push button is for the safety reset and round toggle switch is a limits bypass. The ones in the middle seemed a bit small so I bought larger ones which can be seen on the top left of the pic.
Attachment 6805

Adil

They've certainly helped me now view some terms as images... Thanks Adil.

Thought I'd put up my latest renderings of how I want my router built. I went with the L extrusion gantry design which came out on top in this thread, effect-forces-gantry-cross-sections.

A big thanks to Dean for helping me along the way, with which I'm now set on a final design. The drawing mostly concentrates on the gantry and z axis. The x axis is not to scale , just for visual purposes of how the components connect.

So, I've got most of the electronic bits, my profiled rails are on route, and the next thing on my order list is the extrusion. The ali plate order needs some jiggling as I want all small parts to fit on one large sheet, so its easier for machining.

The frame, not pictured here, is still made from welded and bolted steel box section.

The x axis drive will also be upgraded from 1 motor and a long belt, to 2 motors and 2 short belts, as my new drivers have stall detection. Will need to buy the extra motor and driver.

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I remember being advised that it was better to keep the ballscrew as close to the z axis as possible - between two ali extrusions rather than behind one...This is maybe not such an issue with profiled rail? I like how compact this is but does it come at a price?

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Originally Posted by JoeHarris

I remember being advised that it was better to keep the ballscrew as close to the z axis as possible - between two ali extrusions rather than behind one...This is maybe not such an issue with profiled rail?

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That's something I mention quite regularly. Profile rails will help to compensate for the ballscrew not being in the optimal location, which is directly between the rails on the gantry, but it will still be better if the ballscrew is closer. Currently the ballnuts seem to be 'out on a limb' which risks the plates they are mounted on bending which is best avoided.

I suppose when you go for the 'L' shape gantry, there isn't many options where the ballscrew can go. This type gantry was deemed stronger than having two separate extrusions top and bottom with the ballscrew inbetween. Some compromises have to be made, and I chose to go with a stronger gantry design.The statement below which JAZZCNC made form the 'effects gantry cross sections' thread reassured me it will be fine.

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Originally Posted by JAZZCNC

I've built machines using the green design and please believe me you have nothing to fear the strength is easily over the top for anything but steel or harder.

Yes it places the ball-screw slightly further back than what's considered ideal but again it's nothing and doesn't make any difference to how machine performs. The positive is the screw is away from the firing line and protected.

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Ok, just thought I'd flag it up. With a 20mm plate bolted to the back, two profiles on top of each other must be pretty strong though right?!

I have now read the thread cited above and the more I look at this L shaped gantry the more I like it! It's more compact, makes connection easier, its stronger laterally and omits the plate. Just one (maybe daft!) question. How do you join the two profiles?!

I've made a quick drawing of how I will be connecting them. A screw goes right through the bottom extrusions and screws up into a T-nut slotted in the top extrusion. The screw head will be sunk into the D slot for my profile rails to sit flat on the extrusion. Hope it clears it up a bit.

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Thanks, I figured that was how. Just wanted to check there wasn't some cunning way I hadn't thought of!

Think I'm going to be changing my design yet again!!