Newbie Sieg X3 and or Warco WM18 CNC conversions

[CNCMEBABY]

Hi All.

I've had my Sieg X3 languishing for several years, bought with a fried motor control board and recently got started with it, lashed up a 3 phase motor with VFD just to get going but know full well I have to make a proper mounting for it to hold the motor properlystill and provide for tensioning of belt. Started along using https://manualzz.com/doc/23277943/vfd-and-belt-drive-conversion-for-my-sieg-x3-mill--part-1 as an example but am open to advice and changing this along the way as having read quite a bit of this forum am now slowing down and hoping for help and advice here before carrying out any more work or spending any more money. I have made pulleys using the example here, it cuts OK although with the motor mount the way it is there is too much vibration to take an real depth of cut

Locally there is a WM18 for sale that seems to have been looked after, has been CNC converted but had all the motors and electronics removed for another project and left as a manual machine again. I am arranging to inspect the machine this week to try to ascertain exactly what has been done as the current owner is unable to answer my questions regarding whether or not the Z has been converted (I think this unlikely as I see the original Z hand wheel is still on there) and what type of ball screws etc are fitted to the X and Y (maybe Z). I'm looking at this mill as it may be easier for me to have a more stable machine available to work on the X3 conversion. Might it be worth my while to complete the WM18 conversion depending on its status and use the X3 as a nice drilling machine? Or are two CNC mills better than 1?

Ultimately I want to be able to machine model steam engine parts and do these kind of conversion works. I am at an early stage in my engineering hobby, am computer literate but yet to take the plunge with CAD etc so am really really green and looking for lots of pointers. I have seen Jonathon's thread on here [URL="http://www.mycncuk.com/threads/7656-X3-mill-with-rails-ATC-new-motor/page4"] and am inspired to make something special out of my X3.

In total I have a Naerok GH lathe, the Sieg X3, a very (very) small bench lathe, a recently purchased LIDL metal bandsaw and a Draper drilling machine at my disposal. I have been making myself tangential tool holders, sharpening jigs etc to give you all some idea of my current level.

The idea of a CNC mill in the workshop is very appealing, I have studied John Stevenson's conversion in model engineer over the years along with many other conversions. I have made no purchases of conversion equipment bar the 3 phase motor and VFD. Budget is not totally open ended and I'm not in this to make money, this is my hobby and I'm in it for the journey really and to stretch myself.

I am keen to make the most of what I have and to take this all one step at a time, I have many ideas swirling around in my head having seen the motion rails/bearings in Jonathon's build, wonder if motor speed control is possible with the VFD I have etc etc etc.

Anyway, enough for now.

Thanks for looking all!

Stay safe...

[CNCMEBABY]

Hi All,

I have settled on sticking with the X3 I already have and not to buy anything else. I plan to ditch the pulleys I made for the spindle drive and to use a couple of ratios of pre-made toothed pulleys with belts, I just need to make the plates for mounting and a tensioning system - whether that is spring loaded or moving slots is one decision I hope to make with some advice from the knowledgable people here. I will do this once I have the mill moving under cnc control. With the flexibility of the VFD/3 phase motor I don't envisage having to change the ratios too often so this could have a bearing on this decision.

Having spent lots of time reading around here I'm conscious of the regular advice not to buy electronics etc. I will be looking to add a 4th axis in the future, so need to have the capacity for this in the electronics I buy so a 4 axis motion controller

Having said the above, I have just bought some second hand but little used Nema 23 3.1nm steppers + 8mm couplers, originally purchased from cnc4you. They were too good a price to miss. I plan to use these for the X and Y axis motion. I'd like to use UCCNC as it is getting very good reviews and seems well supported with well matched controllers...

Some questions I have are

1. What controller card would suit - I have looked at the AXBB-E, the schematic shows it should do everything I need with the X3 now and in the future due to the capacity for the A axis drive
2. What are the best stepper drivers bearing in mind...
3. I perceive that Nema 34 is the correct size for the Z but could a higher torque NEMA 23 geared down do the job just as capably?
4. Is there a suitable power supply option to buy off the shelf or am I better off making my own?
5. Is anyone who has experience in converting the X3 up for helping out with specifying ball screws, mounts, bearings and maybe doing a bit of machining too? (JAZZCNC I'm wondering if you're interested as I see in Kered's BF28 build you have experience with Sieg...) I'm keen to get this machine cutting things for my hobbies...
6. Finally for now - does anyone know what happened to John Stevenson's X3 conversion pdfs that used to be on the web? I can't find them any more and didn't save them locally - they were a great resource for me.

Thanks all and stay safe,

Geoff

[Doddy]

1. AXBB is fine. I use a UC300ETH on my SX2.7, but only one port (a second port controls, separately, a Starmill).
2. Go Digital drive!, I've used 2DM860Hs but there's plenty out there. I'm sure someone will express a preference.
3. I've used a 3.1nm '23 with a 2:1 belt on Z (same on X/Y). I've never encountered a problem with this configuration - noting the X3 is a bit bigger.
4. Consider your driver options - if you can run AC then it's just a case of bolting a transformer into the control box, it's quite a sensible choice for KISS,.
5. Not the X3, but the long-bed SX2.7. I just replaced each trapezoidal with a same-length 1605 cheap Chinese ballscrew, appropriating the same mounting holes for each axis (though offsetting and mirroring the motors with 2:1 belts into the space-frame of the machine). YMMV.
6. Nope, but I gave up trying to find 3rd party designs (mainly because I don't talk Sketch-up and neither did F360 - in the end I realised I was wasting more time chasing these than actually just eyeballing the machine and designing the plates, mounts etc myself.

Just my experience on a SX2.7L - not the X3, you'll have to take the above with a pinch of salt.

[CNCMEBABY]

Thanks for the reply Doddy - lots of food for thought.

Hope you don't mind if I follow up your replies with a couple of extra questions?

4. Could you pass some details of this solution - I have been looking at AndyUK's router build and considering copying what has been done there mainly due to the exceptional schematic he's put up - albeit with some down-speccing in a couple of areas, I don't think I'll be needing anywhere near the amps he's using, although if I'm going to be going 4th axis then I might need it all or close to it, I'll have to finalise my sums.

5. Did you use the existing bearings at the ends of the table for mounting your ball screws / did you upgrade the bearings to something like opposing taper bearings - the X2.7 might be better as it's a later machine but my X3 has quite horrible bearing races and was expecting to make new plates for mounting BK/BF12 mounts - still to do the CAD model for the XY table, been learning Fusion 360 with Lars... Having said that I could get the ball screw stepper end threaded by the supplier (Fred at BST perhaps) and thread the stepper shaft coupling to suit the end of the ball screw and adjust that way and use better bearings in the existing plates

6. Coming to the conclusion that you are spot on about this, time to jump in

Thanks again,

Geoff

[Doddy]

4. Some drivers will take AC or DC supplies (nothing special - they just have a rectifier to take whatever and make sure its DC internally. Normally there's a smallish cap inside to smooth the rectified supply). With these - just get a suitably rated transformer and present the secondary winding to the driver. If you have only a DC driver, then you need to provide the rectification and smoothing cap yourself. It's slightly more complex, and adds £10-£20 to the build, and more space is required, but it's still straightforward. AndyUK provides some excellent documentation of his builds here - by all means follow those, but feel free to ask any questions - particularly PSUs there's not a whole lot of complexity required here, and ask any 5 of us, and you'll get 6 different opinions :)

5. On each axis I used a BK bearing block at the drive-end (integral AC bearings). On X I used the existing brass bush to support the end of the screw - simply, it was there and it fit perfectly well. On Y, I left the free-end floating (it's only something like 25cm in length, and there wasn't easy space under the bed to mount a block. Similarly on Z, left the end of that floating - plenty of space in this case but there didn't appear to be much need to support the end of the Z screw. Others may have different views on this.

29485

Example on Y.

6. Yeah, jump in, what have you to lose?

[Mat]

I've got a copy of the X3 conversion articles previously on Arc Euro's website...
https://drive.google.com/file/d/1sMqx5VzE42IhYh0yvGL-DOMD1WGUjE94/view?usp=sharing,
https://drive.google.com/file/d/1sS4OwiKclRbw28_lInKv124f2UUUeEbS/view?usp=sharing,
https://drive.google.com/file/d/1sZ6Y_ETuG1C_B3SUQvxb5w7Tf9zrkBZS/view?usp=sharing

[CNCMEBABY]

Hi Mat,

I tried the link but don't seem to have access...

[CNCMEBABY]

Hi All,

Progress!

I have measured up and decided on following two people's methods to get to where I want to be.

I have decided to follow the same approach as Heavy Metal CNC's X3 conversion Z axis solution.

Doddy - I'm copying some of your work on your X2 conversion, using plates on the end and front of the saddle and will use equal size pulleys initially to get the steppers out of the way a bit but leave myself the option to use a reduction drive if required - any thoughts?

I will be using 1605 doublenut ball screws for X and Y and a custom machined 2005 on the Z.

I will machine out the existing Z ballnut aperture to suit the larger 2005 ball nut and use the existing top bearing and lower thrust bearings as they all seem to be in good condition. Just waiting on a quote from Fred so is there anything else I could do with considering while I'm at it? Otherwise relatively confident thus far.



I have taken delivery of lots of lovely aluminium bar and have my BOXZY mill to do the cutting work for me when I get to the next stage.

[Mat]

Trying again with dropbox:
https://www.dropbox.com/s/7brnh2xznfmsr7u/x3_article.zip?dl=0

[Mat]

I will be using 1605 doublenut ball screws for X and Y and a custom machined 2005 on the Z.

.

Just bear in mind that you'll need to grind off any flanges, there's about 36mm of space, I've used 1605 ballscrews and the nut flanges were 40mm across. I ended up grinding 2mm off top/bottom on the Y axis and 4mm off the top on the X axis, centre height on X ended up at 21mm (22.5mm originally).

Also, check the length of your double ballnuts on the y axis: you can probably fit about 23cm of screw in there before it hits the column, so if your nut is 10cm long you'll restrict your travel to 13cm.

[Doddy]

Also, check the length of your double ballnuts on the y axis: you can probably fit about 23cm of screw in there before it hits the column, so if your nut is 10cm long you'll restrict your travel to 13cm.

THIS!, eyeball the axis broken down as a sanity check!

I don't remember grinding my nuts on the Y, but defo on the X.

[CNCMEBABY]

Thanks Mat,

Is it an X3 you've converted?

I've double checked the ball nut diagrams and read them correctly now I think.

A 1204 with a ball nut height of 30mm would fit within the existing brass nut housing for ease of machining and single ball nut might be a better choice for the Y given the travel issue you mentioned. Just thinking, it could be feasible to have the regular ball nut (or indeed a double nut) mounted backwards on the screw to gain the maximum amount of travel. Would need to offset the BK mounting further forward from the front of the saddle but that should be easy enough with a suitable lump of aluminium. It would protrude more and really necessitate the stepper going off to the side with the pulleys and belt or I'd never get past the thing in the garage .Following on from that it might just be easier to use the same 1204 for the X in that case. I'll have a look at it shortly - the table is already off so should be easy enough to work out. Glad I haven't ordered just yet.

Shows the value of this site and the experience on here again for me..

Not sure if I want to grind my nuts!!

[Mat]

Is it an X3 you've converted?


Yes, though it's not 100% complete yet, the mechanicals are done and I've got the motors spinning in the bench but I've not put it all together yet.
Also, I went with these massive 8Nm Nema 34 steppers that a friend donated and the mounts are made are massive so I'm already planning Mk2 !



Just thinking, it could be feasible to have the regular ball nut (or indeed a double nut) mounted backwards on the screw to gain the maximum amount of travel. Would need to offset the BK mounting further forward from the front of the saddle but that should be easy enough with a suitable lump of aluminium. It would protrude more and really necessitate the stepper going off to the side with the pulleys and belt or I'd never get past the thing in the garage .


Yes you can push the nuts forward to gain space and you'll get more space on the underside, but you don't gain any headroom.

Another thought: if you're planning to offset the stepper, on Y you'll need to offset upwards as there's no space to go sideways, you've got maybe 80mm width until you hit the dovetails.

I'm currently modelling a homebrew double nut 1204 solution:

29693
29694

In theory the length will end up being 74-77mm so would need extra space on the Y.



Not sure if I want to grind my nuts!!

It's not ideal, but it's not too horrific. You'll need to take the nuts apart to clean them after grinding - daunting if you've never done it but there are vids out there and all you need is grease get the balls to stay in place as you load them back in.

[CNCMEBABY]

Yes you can push the nuts forward to gain space and you'll get more space on the underside, but you don't gain any headroom.

That sounds good...




Another thought: if you're planning to offset the stepper, on Y you'll need to offset upwards as there's no space to go sideways, you've got maybe 80mm width until you hit the dovetails.



Maybe it won't be so critical to offset the Y in that case as I'll be losing the power feed from the end and all the space it takes up. I could retain the pulley drive and have the stepper on the same plane but just offset it towards the rear a bit, losing one of the pulley thicknesses from the equation.

I might have to draw my ideas up in Fusion tonight, I have the saddle modelled up already and a picture speaks more words after all, but then I might just measure up again get the screws ordered and take it from there.

[CNCMEBABY]

THIS!, eyeball the axis broken down as a sanity check!


Been having a good measure up. With the saddle all the way back to the column there is 5mm of existing leadscrew nut covered up, this being the backlash adjusting part of the nut. This could be removed in the quest for the greatest X travel if required. Even without removing that 5mm of metal I reckon I can get 200mm of X travel including a nut on the end of the screw to prevent accidental over-travel. So plenty of travel for the 160mm table with a safety margin.

I might put a couple of belville washers in to preload the nut to account for any backlash a la Jonathan's micro lathe job here (http://www.mycncuk.com/threads/4497-Micro-lathe-Zero-backlash%2A-conversion/page2). This is due to me using the 1204 and there not being a double nut option. The bonus is I can get the nuts in just without having to grind them - the 1204 ball nut height at the flat of the flange is 30mm with the leadscrew nut coming in at 35mm. Just enough meat...




I'm currently modelling a homebrew double nut 1204 solution:

29693
29694

In theory the length will end up being 74-77mm so would need extra space on the Y.


Having said the all above and read your plan for the antibacklash double 1204 nut, an easy double nut solution would appear to be to bore out the existing leadscrew nut as planned anyway for the first ball nut and mount another back to back with belvilles between to preload and use a couple of the mounting holes on the ballnut flanges between with one flange threaded and the other opened out slightly to use bolts to apply the preload. Then the space created by all that can be used to mount the stepper with the shaft facing out and on the left hand side of the saddle. I plan off-stands made from aluminium block for the spacing for the mounting plate off the front of the saddle.

[dazp1976]

Been having a good measure up. With the saddle all the way back to the column there is 5mm of existing leadscrew nut covered up, this being the backlash adjusting part of the nut. This could be removed in the quest for the greatest X travel if required. Even without removing that 5mm of metal I reckon I can get 200mm of X travel including a nut on the end of the screw to prevent accidental over-travel. So plenty of travel for the 160mm table with a safety margin.
Having said the all above and read your plan for the antibacklash double 1204 nut, an easy double nut solution would appear to be to bore out the existing leadscrew nut as planned anyway for the first ball nut and mount another back to back with belvilles between to preload and use a couple of the mounting holes on the ballnut flanges between with one flange threaded and the other opened out slightly to use bolts to apply the preload. Then the space created by all that can be used to mount the stepper with the shaft facing out and on the left hand side of the saddle. I plan off-stands made from aluminium block for the spacing for the mounting plate off the front of the saddle.

I basically didn't like the amount of front overhang so wanted my saddle to move closer to the column.
I cut my base slot a bit, made some new bolt holes instead of using the large central one on the carriage.
Managed to get my saddle to move further back by 15mm. Overall I got 204mm movement from it with barely any extra overhang.

However. My throat is only 185mm but at least I don't need to hang off the front a mile. Later on I'll stick a 20mm spacer between the slide and head. Then I could use the whole 204mm.

This is on an Amat25lv similar to the Warco machine.

[CNCMEBABY]

All the ball screws, nuts and pulleys arrived in pretty short order from Fred at BST. He was exceedingly helpful with my questions, raised issues I hadn't foreseen and coped with my hand drawn diagrams admirably.

I got given a really nice control box donated from a friend, unfortunately I'm having trouble uploading the photo, I'll try again later in the build when it's been repopulated with shiny stuff. I'll post a list of the hardware I've bought for the control side at the same time.

I've been milling out the X and Y ballnut holders from the old brass acme leadscrew nuts. The Y nut was clocked from the front of the table as being 0.002" out of square so compensated for this in the vice on the mill then faced and bored the ballnut hole and bolt holes. I ran into some problems in the process on the second mount as evidenced in the photos below. I had a cutter slip in the collet which accounts for some of the problem, the other marks in the bore are a result of the previous threading showing through but the final mounting hole is true and the otherwise ready to start the fitting of the ball screws.

2983929838

I will get a good bit of extra table travel in the Y axis towards the column as dazp1976 says above on his similar machine.

On final disassembly of the old Z axis bits I found that the damper had long since given up the ghost - I wonder whether to get another or just rely on the power of the stepper?

[CNCMEBABY]

Hi All,

Trust you all had a safe and good festive period.

I've spent a vast amount of time getting to grips with Fusion 360 and been modelling up as much of the X3 as possible with as much accuracy as I reckon I need. Link to fusion design here https://a360.co/3EeD874.

I also spent a large amount of time in the shed making my Y axis stepper mount plate, much swarf, many broken cutters from trying to get used to machining with a flexible machine and a low powered router head. (BOXZY robot)
So here it is, my Y axis plate with stepper mounted at the rear so that it doesn't stick out the front too far and take up too much room in what is already a small space.

Any suggestions for good pulleys and belt to stop backlash before it gets introduced much appreciated - I've seen mentions of HTD5 and am thinking 15mm with 18 tooth pulleys.

Cheers all.

30753