CNC Routers for FRC Robotics


#301

Thanks for the input! Is the x-carve at all feasible as a main CNC? I suspect you probably can’t get tight enough tolerance for a lot of parts. It looks awesome for quickly knocking out wood prototypes.


#302

The x-carve is an extremely light duty CNC. Good for plastic and woo, but painfully slow on Aluminum. Spending 2-3x more on an Omio will net you 10-50x more performance, easily.
The Shapeoko 3 is pretty cheap, and is a more rigid machine than the X-carve for a similar price.


#303

We received our Velox 5050 router a few weeks later than planned, so it was being used pretty much non-stop Feb 1 until mid March.

Our priority going forward will be to purchase other tools like a horizontal band saw, improved tapping capability,etc. to support the productivity gains provided by the router. I would think that a combination of a good CNC router and well trained team members would allow a team to knock out quick small parts along with the parts critical fro meeting the build schedule. Another option would be to spend the extra funds on improvements and supplies for the main router.

Top on our list is an enclosure and an improved tubing jig.


#304

Yeah, that’s what I was afraid of with the x-carve (and tolerance issues since it’s not the most rigid.) How slow going is the Shapeoko compared to something more like the Velox? Watching some Youtube videos of it, the thing looks like a beast and not noticeably slower.


#305

The Shapeoko will be far slower and not as accurate, even if it’s better than the X-carve. If you want a cheaper CNC, buy an Omio X6 or X8 if at all possible. Anything less will not give you as good results. 3991 made a S3 work this year, but it was a struggle to get everything dialed in. Great for polycarb, but aluminum was a chore.


#306

For fast wood prototypes and lexan, we used the x-carve to death. We would pump out 2-3 intake revs in a 2 hour time gap with testing them. Make a nice dust boot setup for it so you don’t have a mess everywhere and we used HDPE as a waste board with surfacing once a week during peak use. If you are doing anything besides wood or lexan, get a better router. We used it occasionally for 1/16 and 1/8 when waterjet was backlogged but it is slow and accuracy is mehh.

-Ronnie


#307

Quick question that’s probably a little dumb, is there any reason to use the x-carve for knocking out wood prototypes rapidly other than to keep the better CNC free for metal parts? I assume not, I can’t see any reason to, but just thought I’d throw the question out there.

Thanks everyone for your inputs!


#308

Nope. The more rigid and powerful machines will fly through wood/plastic.


#309

What spindle speed and feed rate do you use with a 3/16" drill bit? We haven’t tried using drill bits yet but it is something we need to do.


#310

It depends on how thick of a material you are trying to drill through. For example if its a thin sheet metal, 1/4" or smaller we drill straight through. If it is thicker then that we do a drilling operation that plunges, then retracts, then plunges again, also known as peck drilling. This allows you to clear chips. I dont know the numbers off of the top of my head but I can look them up and send them to you. However we got to our numbers through trial and error


#311

Question for those with Omio routers using Mach3.

We received our X8 a couple of months ago and are just now getting to work with it. The Mach3 initial installation from Omio has everything set up for metric (mm)…not surprising.

I’m looking to convert the units to inches.

I thought at first it was simply toggling the switch on the “Settings” tab from MM to IN. But even if you “Save Settings”, every time Mach3 is closed and reopened, the units on the Settings tab default back to MM.

Did some web searching and a few videos on Youtube hint that there appears to be more to do. First, under the “Config>>Select Native Units”, you can toggle between MM and IN. But, that affects the three stepper motor setups. So then you need to change the settings under “Config>>Motor Tuning and Setup”.

That is where my question comes in: what are the values folks have used to switch from the default setup for metric values to whatever is needed to tune for inches? There doesnt seem to be a lot on the web that makes this process easy…or I’m looking in the wrong place. I tried using “Axis Calibration” on the Settings tab…but that produced dreadful results.

This is all stemming from trying to get then included Z-axis touch plate working. The default code from Omio appears to work great when in metric mode…but when switching the units to inches…and using this code https://www.youtube.com/watch?v=G4DeVa8rzA0, I’m not getting the tool to zero properly (stops too high). This is leading me to believe that the axis motor settings could be incorrect and need to be changed for inches.


#312

Why not just use the machine in millimeters? Your CAM program can easily just output your parts in mm.
You should be able to tune your steps/unit with inches or mm. It’ll just be 25.4 times higher for inches.


#313

Unless I’m misunderstanding something, you should be able to just add G20 to the Initialization String in the General Config, then all the DROs would be in inches when you boot up.


#314

I have a 1.5kw chinese water-cooled spindle from eBay, and have been using it for over a year. It’s actually pretty high quality and has taken alot of crashes while I was still learning. I highly recommend it.


#315

Adding onto this, I bought a 2.2kw spindle/vfd kit for 299 a year ago. We had several failures on the VFD, so ultimately we had to buy a slightly higher quality one for $100 off Amazon. The company with the failed VFD did send us a replacement set, but the second VFD failed too (although they sent a new spindle and water pump as well…). The spindle was fine, however.


#316

may i get some more feedback on this Velox QMTC system. seems like a tormach TTS idea, without the annular indexing which provides side rigidity.
how has it worked for you with router bits/endmills and side loads.

in my opinion, looks like it hangs quite low, may only be good for drilling operations. but maybe worth it just for that?


#317

I will quote Bryan who has shared what we used at 294. We ordered the QMTC from velox but found we didn’t use it. It does have a straight shank like the TTS tooling, but the additional offset length really reduces the travel of the Z axis. (we would have to re-position the router to do the 2x1 tube) Instead we used the following Genswis adapter(see Bryan’s quote). The biggest thing is to really make sure you do NOT over torque them otherwise they are a pain to take out or yu may break the nut. Given that they worked great, no pull out, repeatable offset (for a router).


#318

I called up GenSwiss after seeing the original post on them, and they mentioned that the runout was up to 0.001" on their holders. They also said that they weren’t balanced past 3,000rpm or something (definitely a lot less than the 20k spindle I’d be using them on). Have you noticed this being a problem on smaller endmills that might hurt from the increased runout?


#319

It is the only thing 1678 uses for our endmills, deals with side-loads just fine. For drilling we use cheap 1/2" shank Jacob’s chucks in place of the ER16 collet holders.


#320

Thanks for your feedback.

I like the idea of a mini Jacobs drill chuck for drilling operations, then switching back to a router bit or endmill.