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CNC G0704 Followup! FAQ, Issues, Costs, and Upgrades!
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- Опубликовано: 18 авг 2024
- Answering a lot of the questions I've received from the original CNC conversion video and sharing a number of updates, experiences, and upgrades to the whole system! Sorry for long winded yapping, but also not that sorry.
Blog post covering costs of the original conversion: practicalrenais...
Buy all the stuff I used!!
Warp9 Ethernet Smooth Stepper: amzn.to/2QuRZX0
CNC4PC C25 BreakOut Board: amzn.to/2PE4udi
CNC4PC C6 Spindle Speed Control Board: ebay.to/2QuG1fS
HiLetgo (“Moujen”) ME-8108 Limit Switches: amzn.to/2Ljsx0W
1/8” NPT 12v Solenoid Valve NC: amzn.to/2QQaF2V
5v Relay: amzn.to/2QSDpI5
2 Pin Aviation Panel Mount Plugs: ebay.to/2PDs6yX
3 Pin Aviation Panel Mount Plugs: amzn.to/2QSDQ5b
4 Pin Aviation Panel Mount Plugs: amzn.to/2LmaV4A
Shielded Spindle Power Cable: ebay.to/2QQb9pL
Shielded 4 Conductor 18ga Stepper Motor Cables: ebay.to/2BlHWcs
The LED ring I put on my Spindle (I didn’t mention it but it’s neato) ebay.to/2rC1VPH
The stuff I used for the original conversion:
G0704 Milling Machine: ebay.to/2y7Ximm
1600oz/in Stepper Motors/Drivers/Power Supply/Breakout Board: ebay.to/2t9tkc6
Double Nut Ball Screws: ebay.to/2EyZyFP
USB Smoothstepper: ebay.to/2JI804m
MACH3 software: amzn.to/2ybvkpP
Thingiverse Links for all the 3d Printed stuff!!!
The homing switch mounts I made: www.thingivers...
Case Mount for the C6 Board: www.thingivers...
Case Mount for the Smoothstepper and C25 Boards: www.thingivers...
Spindle Ring Light Mount (I don’t talk about it in the video but its super neat!) www.thingivers...
www.PracticalRe...
PATREON bit.ly/28X4419
INSTAGRAM bit.ly/1NLu9zv
SUBSCRIBE bit.ly/1OAKcuw
FACEBOOK bit.ly/1YDV3d5
TWITTER bit.ly/1ToGKYm
#G0704 #CNC
Camera: amzn.to/2sXCWaq
Microphone: amzn.to/2MpiMOC
Thanks for posting the project. I also appreciate your honesty regarding mistakes. It helps the rest of us avoid similar errors. Cheers
Practical Renaissance - Here is a nice addition you may want that allows you to still use your mill for quick manual milling. Add hand wheels on the x and y that have encoders telling the steppers to follow them. I used a ProtoTRAK CNC mill that had this feature. You could square up the stock quickly using the hand wheels then tell the CNC to go. It was awesome. Two modes: CNC or manual. Handles had a little resistance so they wouldn't spin on their own. Z was up or down, fast or slow by motor to help with quick bit changes. The quill still had a manual feed that you locked in place for CNC. It was a great machine. Nice job on your conversion. I especially enjoyed seeing the chips fly at the end. Be careful about noise levels from the air blast as well as breathing the oil misting in the air. Cheers
i pulled up your channel today and hit play all and was highlight of my day to see a new vid! love the content!
Have to give you credit for jumping into to such a difficult task and I feel your pain. I have been slowly building my mini mill for the last two years with a lot of hiccups along the way! There is so much to learn, but like you said well worth it in the end. I have a small harbor freight mill I have converted to CNC and I am also using the warp9 smoothstepper and Mach3, it is almost finished, but I can’t figure out how to control the motor with Mach3. BTW for spindle RMP I used the iMach spindle tach, it’s USB and plugs right into your computer. All you have to do is make a black line on the spindle and it works perfectly. Great work and keep the videos coming....it’s comforting to know that I’m not the only one who struggles with this stuff.
It is really nice to see you discover the basics of what is the BASIC CNC functionality from within the G-Code file like M03 S100. I started in N/C in 1975, knew many things from the CNC to the CAD/CAM system but, I never got into the electronics. Your work is really great and now you know a lot of CNC electro-mechanical workings that I never had to bother with. When I was young I lusted after HEATHKIT electronic kits. You work combines the best of both of my passions. It is impressive. I have been retired for over 10 years and you have made me want to do one of these projects myself, if I have enough time. Question, what is keeping you from using the MACH4 system? I watched your first video and was wondering where the limit switches were.... :-) Have a good day
Thanks for the great video. I have a Precision Matthews manual mill that I want to convert to CNC one of these days, so your experience is very helpful to me. BTW, one thing I learned about adding tach sensors to my machines is that it matters which way you attach the magnet to the rotating shaft. You want to set it up so that the South pole of the magnet is the one that travels across the sensor. Otherwise, you won't get a reliable signal. Again, thanks for a great retrospective video, and keep em coming!
Hi Jeff, What you have done is completely impressive! Clearly you have a lot of self-confidence, creativity and drive. Inspiring!!! Keep up your great work!
Nice to be here see your mill we run a single table top CNC mill built it ourselves (only one we have) as well, we make little parts and it did get lost sometimes so we hear you there but it is now refined down to being a non existent issue. We have just a TAIG enough machine for the micro machine world we live in, mostly under 1.5 inch or less. Thank you for sharing have no questions today. We cut Titanium 6al-4v bronze 932 and aluminum 7075 and 316 stainless just sharing our materials but what cut depths and speeds and feeds is a slow patients required approach, but it gets the parts cut. We bought the limit switches but we have not installed them (i.e. built the brackets for them)
That current meter on your controller should have an internal shunt. But the schematic I saw has the negative terminal of the power supply running through the meter, not the positive. That is opposite of what I would expect. The current meter is just measuring the voltage across a low value resistor (0.1 Ohm?) on the meter board, you might be able to troubleshoot the PCB.
Thanks for an awesome update. Good to see things are back up after the catastrophe.
I bought this machine YEARS ago and all the stuff for the CNC conversion. I even started making some of the parts... just never finished it. Now i need to find the DVD again to download the plans lol
I am so impressed how you take the time to answer everyone's questions. I have a G0704 setup just like yours... well not as advanced yet. Would love to see you do the mach3 spindle control setup. and thanks for doing this cause I know how frustrating these builds can get. Suscribed for life. Your doin great work.
Hey Jeff, great project, wish I had the time and patience to try it. With too many hobbies I think I’d forget what I’ve learned before I got it finished at my age. Lol glad your back making videos.
Just watched this as also looking at converting a mill to CNC control. Have subscribed! Great followup to the original video on the conversion
I really appreciate your going through all of the problems that you had and your "grit" in working through them. Good work, thank you for sharing, and Happy New Year!
Really like what you do. I have industrial size machines but find the projects you are working on fascinating. Good work
Although I recommend for the time and money involved in doing this, they might have just bought a older second hand industrial vmc with a fanuc controller, but in saying that; this is a great experience for anyone indeed and you did a bang-up job mate!
If you can get a Fanuc that's not plagued with issues for under $4k and runs on household power and fits in your shop, you can't go wrong.
If you are instead 8k into the machine, with a few months chasing down gremlins and spending a few hundred or a few thousand on fixing the machine to run true, and then have to spend a few thou more on a rotary phase converter (or digital one with the nut to handle a VMC) then you still have probably a really good deal for a machine that demolishes these little units, but budget wise you're 3x or more the cost of one of these mini mill conversions, with a lot less floor space left over and probably everything smells really bad now.
I did a PM-25 conversion about 3 years ago. I got some useful work out of it, then blew the stock spindle out doing one 50pc aluminum cutting job. The work needed to upgrade the blown spindle and get everything really dialed in to maximize the potential of the machine just started to get excessive and I ran out of simple turn-key sort of solutions. Meanwhile my other projects got more ambitious...
So at this point we probably will indeed look for a well-kept, lightly used VMC in the 30-50k range and just really jump into the proper machining world.
@@scottwatrous With an already working CNC mill like this one and a decent lathe, you could build your own VMC using epoxy granite for the base with a BT30 or BT40 spindle for less then a lightly used VMC. It's allot of work but it would demolish that overpriced lightly used VMC.
Great summary and interesting that us G0704 owners end up doing very similar things :-)
If you got the budget I highly recommend upgrading the spindle to a belt drive. I have the minipro.com kit, but any kit should work fine. It makes the whole machine run much smoother with way less vibrations.
After that switch to a VFD with either a 3/4 or 1.5HP 3-phase motor. Having high torque on low RPM makes machining steel so much easier and of course you can push the machine much harder. For me 1.5HP is just about perfect, I can tap a 1/4-20 thread at 120rpm into aluminum with no issues. A 1.5HP D80C framed motor (Leeson 192248.00) just barely fits with some mods to the fan shroud and a 3/4 HP D71C framed motor (Leeson 192047.00) fits easily.
Leeson motors are sometimes on sale, look out for deals. As for a VFD a standard Huanyang works greats and Mach3 supports it with a driver. Weight becomes a problem of course, so I had to install counter weights on chain rails.
The spindle is definitely the next "big" upgrade to this setup, definitely a belt drive and ultimately another motor (probably just keep going till I smoke this one lol). I'd really like to get 5000 RPMs out of this setup, more if I could but I'd be happy with that number. Right now just by juicing the pots on the speed controller board, I can get 3100 RPMs, its theoretically still within motor specs but I can't help but think I'm pushing it
Good videos. I have been debating "build or buy" as far as a CNC mill. Considering the various issues you had, all the work you had to do, and that you're way more meticulous that I am, I am leaning heavily towards BUY.
Wonderful to see you back Jeff! Someone might be triggered by the lack a face panel on the head, until... :) The mill I previously had was shipped by freight and in transit the ring on the conduit connector came off, only to short out the VFD when installed. Probably will be easier to use an ammeter on the main line to the BLDC drive instead of using a DC ammeter between the drive and motor. A power meter is more accurate but the response rate is too slow.
Thanks Kent! I love doing things to upset the unreasonable people ;) The grizzly mills actually use a regular boring brushed DC motor; the motor controller is a pretty simple affair, by way of comparison. Still, good ideas though! I picked up the ammeter almost as an afterthought but now that I'm forced to "tinker" with it, I may reconsider how I want to implement it.
welp ive got parts on the way finally so lets see if i can do the same for myself, awesome video homie.
Love the Tormock sign!
Spindle control video? Need to check to see if you have that out... I bought a G0704 new back in 2015 and now looking into converting to CNC. Your videos have been extremely helpful. Thank you!!
🤣🤣 2:11 made me sub. Knew EXACTLY what you meant.... Thanks for the knowledge too.
"there was a chip guard...that I removed immediately" lmfao.
Good to see you Jeff. Great break down on the mill.
Thank's Greg! This project bogged me DOWN and I'm glad to get past it and back to making videos more regularly! Looking forward to more of yours too!!
Great video thank you for all the information..
will definitely be buying and doing the conversion. This is a great great way to get started 😎🙌
Hell of a project, great work and documentation.
Great video and critical analysis. I would like to know how you set the offsets for the tools. Do you touch-off using the machine or do you do some measurements of the tools and then lock the tools in and assume correct Z ? Just trying to understand the tool change flow. Thanks.
Fantastic channel! Keep up the good work. I'm embarking on my own cnc project and you have helped me greatly!
I was watching the previous video as well, and if you haven't done it already, you should bolt the machine to the floor and level the bed to dead zero. It wil give enormous precision and more easy cuts. Less vibration = longer tool use.
Or just keep machining aluminium ;p
You always have superb content. I really enjoy watching your project vids
I bought the same stepper Longs kit: 1600 oz-in steppers with the DM860A drivers. From the dip switch settings in the video, it looks like you are running the driver at 4.9A peak, 3.5A RMS current and the pulses per rev at 2000. Now that you have been running this a few years, would you still recommend those settings. I figure I may as well start my system off where you are at. One less thing to troubleshoot for me. Thanks for the pioneering work on this configuration!
Great video. Thanks. Gonna look into that spindle control board. Id like to see a video on just that:)
thank you for the switch mounts!!
I think you should get the Nobel... for your work because its that great!
Possibly just a speak-slip but just in case it was not....torque is a product (r x F). Torque units should be oz-inch not oz per inch. Other examples are ft-lbs, N-m.
i was going to convert mine but i don't have the time to do months of fixing and adjusting so i think il keep it manual and look got as similar size pre-built CNC the carrvey looks somewhat ok
Heads up, for the amp meter, you have to measure ONLY the positive or negative lead. If you just shove the whole thing through the pos, neg and ground it won't read anything.
Thanks for the Video - How about showing the wiring for the boards.
Jeff, thanks for all the info in the vid AND the follow up link to your website is great! Does Longs offer a "smaller" motor kit? Would you still do the larger motors if you did this over?
Could you perhaps post some resources on how you set up the machine in fusion, got it talking with mach3 and set up the machine with mach3. This could be very helpful :)
I had 6 feet of number 14 that I suggested may cause noise in a PLC cabinet!!! It went to China without changing the wire to shielded cable. They had problems so 3/4s of the shop went and I stayed behind. What was wrong 6 feet of 14 stranded wire!!!
Excellent presentation.
Thanks for posting this . What kind of spindle motor did you upgrade to and what RPMs are you getting.
Thank you for the videos and instructions. What kind of accuracy, or resolution, can you get with a CNC mill like this ?
Thanks for the update! And since I'm almost a year behind on my watch later list, maybe it's even time to make another that I can watch next year? :-D
Next time try to find music for the montage that is more repetitive, though. This one had at least 4 notes too many. ;)
Thank you very much for your video, I just finished the retrofit of my own mini mill (x2) and I have been having issues with backlash, control, etc. I am also getting about 2 thou of backlash and I wanted to know how has backlash affected the precision of your parts? are you able to bore precisely with just helicoidal interpolation?
Again thanks, It's also been a year of learning (meaning lots of troubles and little wins) and it's nice to share someone else's experience!
Holy crap I have run horizontal mills bud not sure I could build one cudos brother
Nice work! Any chance you could post a rudimentary wiring diagram with the new electronics? I'm building a CNC with an Ethernet smooth stepper and it's c25 BOB and had problems finding any wiring info. Thanks!
Check your setup in mach3 for your spindle rpm reading.
Good job on the CNC thank for the info on your web site about pricing. IT make me think a lot about your choice of should I buy a tormach or should I build my cnc To be or not to be that is the question.
Hmm what motor is that a 1kw ? I did see this mill isn’t that great for shell mill’s bought a very expensive one and it left scratches. Had the same thing with the same rpm’s in a dmg (yes i know different classes) and it left a mirror finish
Can you provide a tooling list needed?
Great videos!! By the way, do you usually use Lester ammo when you hunt?????
Great videos. Thanks for doing them. Does anyone have comments on Mach 4 vs Mach 3 software?
Hola.
Por favor actualiza los enlaces de amazon y ebay
Great video!! I was very happy to see your followup and commentary on how the conversion is working. I've been having a hard time deciding on a mill to get for a conversion. I have a G0762 manual mill that I really like and the G0704 seems like the most used mill for conversion. I have been concerned about the G0704 being a little too small (power, rigidity, work envelope, etc.) for cutting steel. But you have been able to handle all the material that I would be using.
If you had it to do over again would you still select the G0704 for the conversion? Also would you use the same steppers and other controller selections you made?
That's a really good question, at this point since the price on the G0704 has gone up, one may as well go ahead and get the model Precision Matthews offers, the PM25, it comes with a number of niceties that the grizzly doesn't have (better motor, belt drive spindle, few other litlte upgrades like that) and is nearly an identical platform. I was just proven earlier tonight that the G0704 can be picky with steel, you have to get your work holding and feeds and speeds pretty well dialed in or you can get some vibration, but it'll do it just fine otherwise. The stepper kit is fine, although you probably don't need the nema 34 motors, you can probably get higher speeds with the types of Nema 23s (on X and Y, a 34 for Z still) and still have enough power to do the kind of cutting this mill can handle. As for controllers, absolutely go with the Ethernet smoothstepper over the USB.
@@PracticalRenaissance Thanks for your input. I look forward to more of your great content.
So does carbide provide a benefit at lower RPM like this mill uses? Seems most people with hobby mills typically run HSS.
Thank you for the follow up. The one thing I really didn't follow (maybe cuz I'm listening at werk) is the Z axis ballscrew problem - were the gibbs too tight? Was the ballscrew out of plumb?
This sounds like something I want to do in the future. Another Q: did you ever think of stiffening the backbone either by adding say an I beam or bolting to a solid wall?
Thanks again.
basically where the ball nut connected with the head was spaced incorrectly, so it was pushing on the ball screw during travel. Some folks have done that with the mini mills (bolt a beam to the Z column) and I'm not opposed to the idea but I don't think its quite necessary yet.
I know this video has been posted last year but if your able to see this comment have you tried the Centroid Acorn CNC controller? From what I have heard it is the go-to controller for DIY CNC now. Also great video!
Damn $299. That cost as much as my whole CNC machine did! I only have a little engraver but still. By whole machine I mean including the PC I use as a motion controller. The software, all of it. Plug it in and go.
Finally this is sweet, so how long till we see that foreshadowed 4th axis
I've got it all figured out in my head just waiting on time and funds!
It kinda sounds like you've spent more time working ON this than with it. If you had it all to do over again, would you?
im jealous about the price I would buy it all right now at that cost
How much of the .002" backlash is in the gibs?
Great video, I have a very similar mill. Did you sort out the spindle rpm sensor (I'm a electronics tech) ?
I have a shop master mill lathe combo unit and was thinking about adding a DRO to it or adding this cnc kit to it as it already has all the mounting brackets for the stepper motor already there. My question is this though if I add a cnc kit will it give me a digital readout like the DRO does? Is there any benefit for both? When looking at the DRO compared to the CNC its only about 200 cheaper so the CNC kit seems like it makes more sence than the DRO at the price point and the functionality. If anybody knows be greatly appreciated ty
You mentioned "Airline" connectors for the wiring. Can you point me to those please. Great video - thanks.
Gx16
link to all the different connectors I used in the description!
I wanna get a prototrak add on for the Bridgeport mill. It uses machinist programming language which is nice and the mill is great too.
I brought a miltronincs vmc for 3500.cost me 1000 to have it moved. It's a 1997 but functions as new.4500! Yes its 3phase but I had a cnc 3phase converter already for my cnc lathe...
Thanks for the Nice Video.
How much did you spend to convert it ? vs just getting one ready to go ?
What DRO system did you put on your mill?
Back from the dead!
Don't call it a comeback!
Mate mate maaate
Love your videos
How accurate is this? I built a CNC router that is within .003 or better. I'm using a surface plate and Gage blocks and am a bit amazed. I would think you get better.
.001-.002, when I tighten everything down I get about .0015" of backlash that I can almost certainly blame on the ballscrews, and I simply haven't gone into the software to do software correction for it. The rigidity of it being a milling machine helps with accuracy too, although I've seen some router setups that are ridiculously stout.
Did you ever add that extra axis?
Try 2 points for a reference on the magnets maybe 4.
Ouch - you let the magic smoke out...... :-( I wanted to look away
Keep going - and sharing - many thanks to you.
Why you painted the whole plate for a small section of letters? ^^
Wheres a good place to go to start learning about machining?
How much are you in for the whole setup?
Do you play bass?
Yup!
It is a common mistake to state torque as oz per inch or oz/inch. In fact torque is force times distance so oz-inch. Torque wrenches usually are calibrated in foot-lbs or inch-lbs. sorry to be “that guy”🤪. I enjoyed your video.
It is no mistake to state stepper motor torque in ounce inches. When you multiply things it does not matter which order you multiply them in either. The values are distributive. 2 x 3 = 6 = 3 x 2. So ounce inches and inch ounces are the exact same thing. We just always express the value as oz/in. It goes with Newton/meter better.
Paul Frederick you missed the point. You did not state it as oz-in, you stated it as oz/inch, same as oz per inch. That’s not multiplication, that is division. Totally different thing. Google dimensional analysis. Oz-inch and inch-oz certainly are the same thing, but oz/in are totally different.
@@sblack48 in "oz/in" the slash is just a text delineator. It is not meant as a mathematical symbol. Technically "oz-in" is ounces minus inches.
Paul Frederick oz-in is oz minus inches? Bwahaha. Dude you are clueless. Go get an eng degree, learn about dimensional analysis and we can talk. Force-distance, oz-in, N-m, ft-lb are what you will find on every torque wrench ever made and what you will find in every physics text book. Text delineator....that’s priceless!
@@sblack48 go fuck yourself.
Did you document the install of the solenoid valve and relay? Did you add an arduino to your system? Where is that connected to? Thank you!! Starting to convert mine and want to implement some of the changes you have made as I do my build.
Thread here: www.hobby-machinist.com/threads/g0704-cnc-conversion-yes-another-thread-on-this.81791/#post-712089
I did not document the process, but what I did was run a simple relay with its activator coming from one of the output pins on my breakout board, which I then mapped to coolant in mach3, the relay simply closes electricity coming from a 12v power supply that activates the solenoid valve which just fits inline with my mist coolant where the old ball valve was. Its a pretty basic and cheap!
@@PracticalRenaissance thank you. I got all the parts that you listed in the video. What confused me a little was the relay. It is for use with an Arduino... Would it be too much trouble to share a photo of what the circuit looks like? Or a quick update in the thread link I shared? Or via Facebook... newbie here and trying to do this :)
top video
With the ethernet Smoothstepper, does your PC still have Internet or network access? (and things of that nature? :D)
I don't see why not- the PC I'm using still has WiFi, however I haven't tried it because I keep my controller PC completely off line (keeps windows update and other random stuff from happening during a cut!)
God I hope not. Mach 3 cannot run on a version of Windows newer than 7 which is EOL now. Really Mach 3 is abandonware at this point. It hasn't been maintained for years. I get that people are comfortable with what they're used to but Mach was never a very good choice as a motion controller. Plus I wouldn't let Windows drive a coffee pot let alone a CNC machine.
@@1pcfred My experience has been quite different. I've been running Mach3 on Win10 for quite a while, on multiple machines and computers. As far as it being viable, I'd have to argue that I've been running it daily for 11+ years with very minimal issues. I've used LinuxCNC and some others, but I've customized my Mach3 screens and macros to suit my work, so it's hard to justify a drastic change at this point. When the time comes, I'll move on to something else.
@@IBWatchinUrVids I guess the Internet is wrong when it says Mach 3 only supports up to Windows 7. Mach 4 runs on Win 10. They look a lot alike too. I don't think Win 10 has been out for 11 years yet either. LinuxCNC is pretty customizable. People write whole new front ends for it. The new touch interface is fire. I might have to upgrade over here. uploads.tapatalk-cdn.com/20181218/9e3418f5dd3deb9c75c876024b83fec7.jpg
@@1pcfred You're right, Win 10 hasn't been out that long. I started using Mach 3 back with Win XP, then 7, and only more recently have been using it on Win 10. I honestly didn't know it wasn't technically supported, I just installed it and used it. I've been keeping an eye on Mach 4 for a long time, it does look interesting, I was just holding off until it was well tested and supported. Maybe I'll try it out on one of my lesser used machines.
Tormock. Excellent
What are you using to drive your spindle motor?
I wanna do a full setup video but the DC speed controller is the same KBIC card that comes with the original Grizzly machine, then I have a C6 board as the go-between from it to the breakout board
@@PracticalRenaissance Thank you for your answer. I am currently looking for a motor driver for my cnc mill conversion. I will look into KBIC cards.
R u going to convert ur lathe to cnc?
Not using Mach 3 he ain't. That never worked right. Seen loads of people give up on that.
Sweet 👍
HELLO NOB CNC GUY, CAN YOU GIVE ME A QUICK DIFFERENCE IN G CODE ,MACH3, AND FUSION 360 IN A NUTSHELL. I know I might be asking too much cheers from OZ.
Not sure if youve found the answer but in laymans terms... fusion360 is the cad/cam software you use to draw and develop parts and toolpaths, these 'paths' are then converted to gcode format which are numbers and letters translating to positional movements of the axes or spindle ( there could be hundreds or thousands of lines) for instance....
G1 x20 y30 z30
Etc etc
Mach 3 or similar programs take/read these blocks of code and send power to the servo or stepper motors on each axis in a manner that reflects the desired paths of the tooling over the workpiece. I might of glossed over a few things but hope that helped
Many thanks Jeff! Everything here are very useful! Subscription and Like from me.
Wht is an "air line" connector? I searched but only find connectors for pneumatic tools
Search it by: Electrical-Aviation-Socket-Connector
👍🏻🇦🇺
for what the total cost is after conversion...i would buy a used true cnc with a good reputation and solid castings. these little mills have plastic gears..dont hold up. blow fuses you cant buy only from china.
Whatever you need to do. My Chinese mill has been running for 28 years now. But it does not have any plastic gears in it. Or fuses that I know of either.
I send you my mill would you do the Conversion for me
No one cares how much torque a motor can develop when it is standing still. What matters is what kind of torque it can develop in motion. Based on the torque chart it looks like those motors crap out at 600 RPM. They're down 50% by then. Which is pretty poor for CNC applications. That's due to their high coil resistance and high inductance. Likely also due to a large gap inside the motor due to low tolerance manufacturing too. They're just not the greatest motors made. Good ballast though.
Hint for a video 1945 ;) Second Amendment!!!