MultiCAM MG101 Gutted & Reborn

Hi everyone!

I'm an electrical engineer by training, mechanical engineer by trade, our company's additive manufacturing subject matter expert by default, and a machinist by the absolute seat of my pants.

My base of experience in machinist work extends to manual mill & lathe work, tig welding, and CNC programming and machining using DIY routers, a bridgeport torq-cut 22, and a Tormach 770.

With a big-boy job and some reliable income, I wanted to land myself a large, capable machine able to perform (to some degree) a combination of the work I've been doing on both routers and VMCs for my projects at home, and in pursuit of a business involving carbon composite tool production.

I was looking, rather unsatisfied, through 6040 router builds and applying for financing options to get my hands on a proper garage VMC (ideally a Syil X7, backup being tormach 1100 MX), when this 20-year-old Multicam MG101 caught my eye on craigslist for $3600:

<a data-flickr-embed="true" href="https://www.flickr.com/photos/thedangerousnerd/48508464707/in/dateposted-public/" title="IMG_20190810_222652"><img src="https://live.staticflickr.com/65535/48508464707_98d1a1121e_z.jpg" width="640" height="480" alt="IMG_20190810_222652"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

I've clearly already started pulling parts off and cleaning this up. My thought is that with modern controls, servos, and motion hardware upgrades, this could be a serious machine for all my needs right up to (and in a very limited capacity including) mild steel.

I bought it from a sign shop who had used it for 20 years and (bless this guy) "greased it every 2 weeks". Certainly can't say you didn't. Never bothered to wipe any off either:

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They were using a high quality Mobil moly grease, and they really did seem to keep up with it. The machine was very tight when I went to take a look, no measurable slop other than a few tenths of deflection in X and Y, the Z is another story. 20 years of travel over the same 2" on this poor, poor leadscrew:

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All their work was entirely 2D, so they didn't care or even notice. Obviously since I'm doing surfacing work, this needs to be replaced with a ballscrew.

The X-axis runs on a 1" OD X 64" multi-start leadscrew, and the thing is still tight. Moves freely with no measurable lash. That said, the pitch is very high and is going to leave a lot desired in terms of positioning accuracy. I'm looking to replace this with a rolled ballscrew:

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I was delighted to hear (and see paper evidence) that the spindle had been rebuilt in the last year. Feels great, no runout, noise, or visible damage to speak of:

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In total, my wishlist is as follows (for now):

- Centroid Acorn CNC Controller
- 4X DMM DYN4 & 86M-DHT-A6MK1 servo kits
- Z-axis ballscrew retrofit
- X-axis ballscrew retrofit

Future work including:

- 2.2kW ATC spindle & tool rack
- Y-axis ballscrew conversion (if the rack & pinion is as terrible as I'm reading)


I'm super excited to get to work on this thing, and am about to pull the trigger on a lot of the controls. I chose the DMM DYN4 & 86M-DHT-A6MK1 as (as far as I can tell) a more powerful and more economical alternative to the similar Teknic offerings NEMA-34 frame. Let me know if I've misread the existing options.

Additionally I'm definitely going with chinese rolled ballscrews to make this a practical DIY build. Does the community have a preferred brand/supplier for motion hardware like this? I know there's a lot of garbage out there...

Cheers,

- Feathers

Looks like a great deal you got there.

Great buy!

I wouldn't rush into replacing the X leadscrew. What is the pitch/lead?

A high count servo encoder should provide plenty of resolution.

Looks like you did well and your choice of hardware is very good. I have DMM servos on my lathe and they work very well. I don't think you need to worry about the high lead screws, my old router had 25mm and 40mm lead respectively on the X and Y and I was easily able to position to 0.0005 inch with steppers, and with the DMM servos you won't have a problem hitting 0.0001 inch consistently. The servos will have much better resolution than your leadscrew error. (all ball and lead screws have some linear error).

For the Z ball screw, go to EBay and find a NOS Thomson or THK ground ball screw w/nut that is the right length.

Thanks for the advice!

The X screw is a 1" diameter, 10-start and whopping 1" pitch. It's super tight so if you guys say you can run sub 0.001" on 25+mm pitch then I believe you! I'll give it a shot. I'll look for a larger timing pulley & belt to give the servo an advantage in this regard. Probably a 50-tooth instead of 30, giving 0.001" per 0.9° servo input.

I found this NSK W1603FA-1P-C3Z+472L ballscrew on Ebay for the Z axis:

<a data-flickr-embed="true" href="https://www.flickr.com/photos/thedangerousnerd/48563886132/in/dateposted-public/" title="z ballscrew"><img src="https://live.staticflickr.com/65535/48563886132_4f43ac9f59_z.jpg" width="640" height="427" alt="z ballscrew"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

<a data-flickr-embed="true" href="https://www.flickr.com/photos/thedangerousnerd/48563742901/in/dateposted-public/" title="Ballscrew closeup"><img src="https://live.staticflickr.com/65535/48563742901_237035e087_z.jpg" width="640" height="427" alt="Ballscrew closeup"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

<a data-flickr-embed="true" href="https://www.flickr.com/photos/thedangerousnerd/48563742891/in/dateposted-public/" title="ballscrew fixed support"><img src="https://live.staticflickr.com/65535/48563742891_f45249659a_z.jpg" width="640" height="427" alt="ballscrew fixed support"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

Seller says these are well used and "can feel slightly backlash". I'm gonna take my chances and enjoy the C3 pitch accuracy in any case if lash is anything better than horrible. The 16mm screw and AK12 fixed support are larger than the 12mm screw and BK8 support this came with. I'll probably have to do some machining to get everything fitting back together properly, including machining the free end of the screw to length (it's a little long for my application), but I'm confident it won't be too difficult. I've got carbide to spare if things are hardened well (as they should be).

The DMM servos are equipped with 16 bit encoders, so they will certainly not be the sloppy end of things :P

Thanks for the tips!

Cheers,

- Feathers

EDIT/P.S.: I'm reading through the Centroid manual on master/slave homing and squaring for the Y-axis. This seems like a very handy feature, but this machine is extremely rigid. With one side locked, I can put nearly all my weight into the other end of the gantry and it deflects ~0.005", returning right back to zero. It seems like I may be able to get this machine very square mechanically, and it's on servo control so I'm not anticipating any substantial discrepancies between executed positioning across either side of the gantry (deviation from electronically geared servo positioning that would cause the axis to lose square).

Is there a good reason I'm not thinking of to retain auto squaring? I'd love to keep the extra axis open on the AcornCNC board if possible, and mechanical squaring would simplify my wiring. Open to any considerations.

Z axis work is done! Got the screw in and there was no measurable lash, seems C3-ish. I'll let the videos do the talking:

<iframe width="560" height="315" src="https://www.youtube.com/embed/6E0at3-9pMI" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

<iframe width="560" height="315" src="https://www.youtube.com/embed/L9Owwvmo814" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

Next up is servos and controls. I'm going ClearPath since the DMM DYN4 are no longer any cheaper, and are definitely not as sexy.

Does anyone have experience with Multicam rack & pinion? Are they any good or do they need to go?

Thanks and regards,

- Feathers

Nice work :) And great video editing.

The two Multicam rack & pinion machines I have worked with seem to be fine. Both were retrofitted with Clearpath servos and those work fine also.

Glad to hear the rack and pinion is working alright. What lash can you measure?

Also what servos did you end up with?

Here's the expensive bits:

<a data-flickr-embed="true" href="https://www.flickr.com/photos/thedangerousnerd/49359181783/in/dateposted-public/" title="SmartSelect_20200109-194036_Messenger"><img src="https://live.staticflickr.com/65535/49359181783_312e58c24c_z.jpg" width="640" height="585" alt="SmartSelect_20200109-194036_Messenger"></a>

Next to the card they dented on the way here...

I feel ripped off on the power supplies for $0.50/watt, but with integrated regen clamping and no clear alternative for 75V, they'll have to do. They'd better be good.

Thanks and regards,

- Austin

Wow, switching power supply for $0.50/watt is expensive. A 1,000 Watt Antec toroidal analog PS is less than $200 and probably better with regen.

Not sure about the backlash, but are pretty tight. They mill pockets in aluminum that are pretty much on dimension, but in this case the tolerances are not critical, just clearance slots for bolts and some profiling. Aluminum is all that's ever run on these machines.

I think the motors were CPM-SDSK-3421P-RLN

This is the power supply I used to power all 4 motors https://www.automationtechnologiesin...vac-or-230vac/

Quote:

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Originally Posted by This is the power supply I used to power all 4 motors [URL

https://www.automationtechnologiesinc.com/products-page/torroidal-power-supplies/unregulated-1440w-72vdc20a-120vac-or-230vac/[/URL]

---

I am not sure but that PS looks pretty similar to Antec PS.

Hi man, i'm in the process of rebuilding mine, and i want to reuse the drivers that it has, do you happen to have the wiring diagrams for the original multicam control box?
thanks
Im Churchil From Fort Myers Florida
[email protected]
239-265-2095

Nice work on your Z screw replacement. Did you install the Acorn controller yet? If so I'd like to hear how it is working and see a photo of your cabinet. I'm thinking of getting one for my MG. thanks, Morgan

It's done! And it's a beast.

I'm in love with it, and at the same time, I recognize it isn't the right machine for me anymore. Over two years, the kind of work I've been doing for folks has shifted more toward a Tormach 1100 or Haas supermini.

So with that said, It's for sale. Starting at $18,000 with all the bells and whistles on this sturdy platform. I know these routers with original control systems and kinematics can run about this much if they're in good condition. I'm in Denver, buyer would pay rigging.

Being a retrofit, I'd be happy to program and demonstrate the desired application for anyone serious about buying.

Here are some videos containing the final work on this router, it includes everything shown. Also demonstrates the precision of this machine, being fully (and painstakingly) compensated on the unground axis.

<iframe width="560" height="315" src="https://www.youtube.com/embed/uNUQE9mmoyY" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

<iframe width="560" height="315" src="https://www.youtube.com/embed/cc-e6Qhr6bA" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

<iframe width="560" height="315" src="https://www.youtube.com/embed/lIclsy3fxBc" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

Here's a list of features:

- 4hp Columbo Spindle
- Teknic Clearpath integrated servos (replaced old steppers)
- X-axis: 1/2hp CPM-SDHP-3441S-ELS
- Y-axis: 1hp CPM-SDHP-3421S-ELS (2 motors)
- Z-axis: 1/2hp CPM-SDHP-3426P-ELS
- Two IPC-5 power supplies
- Centroid Acorn control board
- Centroid Mill Software (runs on an integrated Intel PC)
- Touchscreen interface
- Centroid WMPG-4 Wireless MPG
- Fixed and RF tool touch-offs running a GUI for push-button tool-changing
- Rebuilt Micro-Drop MD1200 MQL system
- Custom retrofit of a 12mm NSK ground ball screw (replaced Z leadscrew)
- New Z-brake (prevents unpowered motion in Z with ball screw)
- 16" X 20" Saunders Machine Works fixture plate
- Saunders Machine Works Mod-vise set
- Plexiglass chip-guards
- T-slot clamp kit

This is an extremely rigid and capable machine, now running 500IPM rapids and with a thrust capacity of over 1000lbs in X and Y. All axes are calibrated, X-axis is screw compensated to ~0.001" over it's entire travel. The fixture plate provided was actually cut, decked, interpolated, and thread milled on this machine, and works very well.

I bought this machine two years ago and have been working on it since. I intended it to be a serious production machine for some work I was being contracted to do, and for that it's served very well so far. More of the work I'm being asked to do requires a higher Z travel, more rigidity (hard-milling molds at 50-60 Rc), and flood coolant.

If you're working for the ultimate precision wood/aluminum working machine and have space constraints, or don't need a 4x8 or 10x12, this is absolutely the machine for you.

Here are some photos:

https://live.staticflickr.com/65535/...9653fdc7_z.jpg20201011_161037 by HighVoltageFeathers, on Flickr
https://live.staticflickr.com/65535/...b674f017_z.jpg20201011_161051 by HighVoltageFeathers, on Flickr
https://live.staticflickr.com/65535/...c58de9f4_z.jpg20201011_161148 by HighVoltageFeathers, on Flickr
https://live.staticflickr.com/65535/...8a64d2fc_z.jpg20201011_161157 by HighVoltageFeathers, on Flickr
https://live.staticflickr.com/65535/...c1c741f4_z.jpg20201011_161213 by HighVoltageFeathers, on Flickr
https://live.staticflickr.com/65535/...4bc5baea_z.jpg20201011_161249 by HighVoltageFeathers, on Flickr
https://live.staticflickr.com/65535/...2f2ab80c_z.jpg20201011_161304 by HighVoltageFeathers, on Flickr
https://live.staticflickr.com/65535/...2e134ffe_z.jpg20201011_161313 by HighVoltageFeathers, on Flickr
https://live.staticflickr.com/65535/...8989251f_z.jpg20201011_161327 by HighVoltageFeathers, on Flickr
https://live.staticflickr.com/65535/...7c080143_z.jpg20201011_161342 by HighVoltageFeathers, on Flickr
https://live.staticflickr.com/65535/...275dbfdc_z.jpg20201011_161419 by HighVoltageFeathers, on Flickr
https://live.staticflickr.com/65535/...8a2def0d_z.jpg20201011_161452 by HighVoltageFeathers, on Flickr
https://live.staticflickr.com/65535/...c398424b_z.jpg20201011_161659 by HighVoltageFeathers, on Flickr
https://live.staticflickr.com/65535/...fe2e58e7_z.jpg20201011_161712 by HighVoltageFeathers, on Flickr
https://live.staticflickr.com/65535/...cf776fa0_z.jpg20201011_161727 by HighVoltageFeathers, on Flickr
https://live.staticflickr.com/65535/...81997232_z.jpgSmartSelect_20200109-194036_Messenger by HighVoltageFeathers, on Flickr

PM or reply for details.

Cheers and thanks everyone for the help with this build!

- Feathers