Hey guys, I have 4 Nema 23 motors from cnc router parts, as well as the G540 setup, can I use them for this build?

Info about the motors.
Step Angle: 1.8o +/- 5%
No. of Phase: 2
Weight: 1.15kg Max
Voltage: 3.15V
Current/Phase: 3.5A
Inductance/Phase: 4.1 +/- 20%mH
Resistance/Phase: 0.9 +/- 10% Ohm
Holding Torque: 28Kg/cm

Thanks

 

Short answer yes
You will need a different Z axis motor mount.
The OX has a Nema 17

If I had the cash I would be using the same setup

 

They were left over from a previous cnc table build, which turned out to be more of a problem and mess, (costs more to fix it than it is to build a new one), so why not see if it goes on a machine called the "OX".

I have the whole setup, mach3, gecko g540, power, computer, motors, I just need a frame and components.

On top of the new Z motor mount, is there anything special I need, additional rails, or wheels to support the weight of the motors?

Thanks

 

I think you will find this link useful
http://www.openbuilds.com/builds/aluminum-ox.592/

 

Hi Gray,

If it's any help to you there is lots of information (and lots of reading) with regard to diode laser engraving in general and engraving shades over 3D routed images in this thread http://hobbycncart.com/forum/63-236-30

Tweakie.

 

I have quite a bit of V rail in stock if you are in a hurry- www.opensourceluthiersupply.com

 

So its been about a month since I finished my build. Here are a few lessons learned that I can pass on:

- Don't expect to be done in a couple days, a week, and maybe a month. While the actual mechanics construction didn't take long (maybe 3-4 hours) the construction of everything else kicked my buttocks (about 80 hours)!
- Don't expect what you buy from open builds being the end all list. For my build I decided on making a couple control boxes and portable table and a few other bells/whistles here and there and ran about another $300-$400.
-When you think you figured out how much wire you will need; double it! Also, found that visiting a local electrical supply store and picking up some 5-6 line shielded control cable was much cheaper in the long run.

A few OX build lessons learned:
- Z Axis: Get eccentrics for both sides of block. This will save some of your hair.
- Z Axis mount nuts should face the spindle. If you have to drop the axis plate for some reason, you won't have to disassemble the entire axis to get done what needs to be done.
- X Axis top wheels, put nuts to outside. If you decide in the future to put some type of dust guard, you can mount without interference.
- The sandwiched y Axis beams. Get some of the light weight double sided sticky tape and put between them (I used 4 slices run the length). This will prevent some vibration from them bouncing off each other. Remember this is not to hold them together, just something to give it a little cushion.
- MDF spoiler board (technically the actual table) is not the best idea if your machine is not going to be in an atmosphered controlled environment or basement. If you do use MDF recommend put at least 3 supports under the table (I used 4 for my 1500X1000 table). Also, let the board stabilize a couple days before leveling/mounting (put it in the hole and let it set). Its truly amazing how much it changed. I also added a nice silicone bead on the inside to prevent dust from getting under the table.
- Don't consider this machine to be a speed demon! Yes I can get 800-1000 IPM with a spindle onboard, but the machine will flex and the jerk is quite of bit of stress on the aluminum frame (and I have 9 points of anchor). I have found 100-200 IPM is about perfect.
- Pulleys are kinda cheap. While they seem to work ok and I am getting zero loss across 52"X30", they just seem to not meet my quality compared to the rest of the machine. Also, my motors had round shafts and had to do some creative filing and a bit of lock tight to make sure nothing decided to grow a brain.
- Taping holes is a pain. Use oil, new tool and take your time. If you have never tapped a hole before, youtube it! LOL It will save you lots of time in tapping a deeper hole and changing bolts.
- I purchased my plates from Chris above. Outstanding quality and fast shipping. Do know that a little dressing will be required, but thats due to the Vslot, not the machining.


Other:

For the novice guys, nothing has been discussed on safety. Before you start your build, you need to master the concept of the E-STOP. I would also recommend looking into limit switches. These things are small, inexpensive and easy to take care of from the start. Trust me the small price to pay now, its definately worth an eye, finger, arm in the future.

I didn't care much for the GRBL so I went with the Planet CNC MK2/4. To be honest, it exceeded my expectations! While the board was around $230-250 I didn't need to drop another $175 for mach 3. It seems to do everything I need it to at this point. Also I did run into an issue and posted on the boards and had a software fix within 4 hours!

For my build I went with some 240 oz motors, LM542A drivers, dual 36V power supplies from longs. While the china stuff is from china, I haven't seen any step loss and get great resolution. Also, took a bit of trial and error to get the amperage settings correct, but now that I have it tuned, it produces almost no heat and sings the CP30 song! As far as the Z, used the Nema17 from OBPS and it does get the job done, but not very satisfied/convinced it could handle 3D for a very long period of time before some replacements would have to made.

All in all I am extremely satisfied with this build. While I went with a much larger scale (1500mmX1000MM) and upgraded the electronics; I believe with a enough experience on how to use basic tools anyone could complete this build. If you can solder and understand basic electronics, anyone could go into a more customized build. The Planet CNC software was easy to setup and took very little effort to learn the basics.

Sorry to be long winded, but wanted to cover a few aspects that I thought would be helpful.

~Kendall

 

Hi Kendall,

Thank you for sharing the retrospective information on your build - it is most informative and will, I think, be of great help to others that follow.

Tweakie.

 

Very nice CNC, would this be able to cut aluminium?

 

Hi Kendall, what width did you use for your MDF spoiler board?

 

Attention all computer Brainiacks: I could use your help. My CNC computer's hard drive went to that big computer in the sky and I had to replace it. I installed a fresh copy of Windows XP Professional w/SP2. (It's my understanding Mach3 won't run on WIN 7 - it requires Win XP.) I am now trying to install Sketchup 2014 Maker however it needs Microsoft Service Pack 3. SP3 won't install nor will the XP updates for whatever reason. (I know-I know Microsoft no longer supports XP as of April 8 2014. But I'm thinking there still out there somewhere) Do any of you out there know how/or where I can get the XP updates and Service Pack 3? Also, is it just the nature of WIN-XP to run so frustratingly slow?

 

Aluminum: I definitely have enough torque, not sure if pulleys and belts could handle it. It is in my near future, will let you know.

MDF is 3/4" to be honest with the low profile of the y axis anything greater would cause issues (IMO).

Photos gonna try to attach some! Sorry for the mess. Making acrylic name tags at the moment.

 

Essentric on the z block and nut on outside (only had 1 extra essential and that done the trick). Got the idea for shifting the nuts half way into it lol.

 

Here is a general idea how big this sucker is. Was pre spoiler board and wasn't quite finished with the cabinet.

 

Google : " windows xp sp3 standalone install "

 

Hello, im Jef and thinking about ordering/making an OX. I originally set my mind upon an Eshapeoko until i read about the OX. The V-slot design when the wheels are pushing on the sidefaces under loads, the wings of the V-slot profile are pushed and because of the profiledesign it has no flesh to push back, so they widen. Dont know how much but they do. Is it possible to add plates or just t nut thingies once every 100mm or so between the wings as in below picture?

 

Sorry on mobile so it's a pain for the quotes.

Z axis alignment: yes this can cause issues, but with some time and the patience of a saint you can get this accomplished. I was only having issues with 1 wheel so didn't have much problems with alignment. I'm currently only doing wood, until I get the $ for a spindle, a little off won't be an issue for 2.5D stuff. Once I get a spindle then I will have a bunch of questions! LOL

X axis flex: I am not seeing any flex. This could be because I ran extra supports under the spoiler board on the outer edges. I also took extra time to cut the spoiler board to give a 1/16" gap between the X axis rails. Then once the board settled into place, used silicone to fill in the gap between the rails and spoiler board. Believe it or not the thing really stiffens up once that board goes in.

Cutting speed: with planet cnc software it has programmed in soft stopping. I haven't messed with the default. For long runs (ie table leveling) was cutting around 200 ipm for the midsection without any issues. However with soft stop I am seeing around 20-30 ipm for smaller stuff and about 40-80 ipm for mid sized stuff (swag). I do not normally override (which will disable the soft stop feature) but when I do, I have it set to 150 ipm.

I normally use cambam for a lot of drawings and have it set to 30 ipm, modifying this to 100 doesn't buy me any cut time, so i just leave it alone.

Think I Covered everything. Have a happy and safe Memorial day!

~Kendall

 

Hi Jeff.

You have a great point, but think you may be over analyzing. Load distribution is across 3-4 top wheels and also inverse support by 2 bottom wheels. If I remember right these wheels are designed for 8 pounds of force. Being spread just shy of 7" should make the v slot immune to spread. I know we have a few mech engineers on here will definitely provide some better/more complete explanations for this, but for me personally haven't seen any issues. Before I would say you see rail separation I would bank on seeing belt and pulley jump or motor stall.

 

I actually got those to keep dust from getting in the slots, but really give the machine some pizazz! I added some work LED lights to the inside of the rails and tapped off my 12vdc power supple, really brightens things up!

As far as X flex I am not seeing any while running. However I do get about 2.8 mm rack effect with the machine off. Running dual steppers on the X axis effectively reduce this to zero. However keep in mind that when you power up stepper motors they lock into the step they are closest too, so in theory they could be 2 steps off (3.6 degrees for me) so depending on pulley configuration that could be a problem. I put a couple marks that i know is true in the middle of the table and I have not seen any issues with this as of yet.

 

Hi Phil
Maybe i am , thnx for your explanation. Maybe an mechanical engineer can tell us more

 

Hi Gray

I have absolutely no data about how much stress it will put on the profiles, i was just thinking about the construction and visualised the profiles made out of pasta and figured what could happen But i think it can not harm to stiffen up the unused slots with lenghts of aluminium/steel.

I plan on milling hard wood/aluminium sheets with the OX if i decide to get one. I know the feedrates/cuthdepths will be small but i figure the amount of stress put on the profile is higher then when cutting softer stuff. The delrin wheels will be squeezed and in combination with the amount of lowering due too widening of the v-slot wings under load, i am curieus what that translates too on accuracy. Say i cut a groove 4mm deep over 500mm lenght will it be 3.7,3.8,3.95mm??

 

I'm very very interested in building this in 2'x4' (and maybe eventually larger) but the part store is out of stock. Does anyone know when the parts will be back in stock?

Great work so far and thanks for your work!