Not economically anyway.
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What about just doing the X axis? Have a 2’ 4’ and 6’ option and the end user can cut down to their specific build? Just a thought. I don’t think the belts on the Y are a problem at all especially with 2 of them. But I have had x skip a few times due to user error and i have wondered if it was ball screw if that would have been better…but then again I have no idea what I’m talking about.
Shipping anything over ~14" outside of the US is extremely expensive.
In my opinion the T8 Leadscrews we would use are going to have way too much whip to be feasible, large CNC’s tend to use rack and pinion.
I am also not of the camp that leadscrews will give nearly any of the benefits most people think they will. Leadscrews introduce, maintenance and backlash compensation. Both things I do not want to deal with. We have extremly low loads and I just do not feel belts hinder us in anyway. Ballscrews are out of the question in terms of price. If we were to somehow boost our rigidity and somehow max out our belts, I would just add a second belt or wider belts. Belts are extremely efficient and superior in most way to a screw.
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Especially with the 9/10mm wide belts. These belts are nice and big.
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Excellent explanation! Thank you for that!!!
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The belt we use is rated at 86N or 19Lbs-f per mm of width. We use 9-10mm belt so 171lbs breaking. Are typical loads are <<9lbs and the Y axis has 2 belts. It terms of Stretch (similar to screw backlash)
I can’t find a stretch spec, but I did find a more accurate torque rating. 8.4lbs minimum for 9mm wide gt2, no maximum listed but I take that as 8.4lbs is what you are shooting for. Gates Corporation Powergrip Belt Drives Gt2 Users Manual PowerGrip® GT®2 Drive Design
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Been following the thread and V1 for a long time now. I wanted to add, that the biggest challenge I see is the software workflow.
There isn’t a lot of documented post processor support for Marlin for the pretty CAM software others use. I know we can also use grbl / whatever else we want.
Many CNC machines lead with software, but then the hardware is not as good. I think we can do a better job leading with a documented software stack or showing how easy it is to use. Sort of like the video you made, but the software part before the actual cutting.
I’m not complaining, and happy to help once I get another machine built.
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What do you feel is missing? GRBL is built into most CAM programs, the most common programs people use we have made Marlin Post Processors and these days we probably don’t really need them as much.
What about estlcam basics? We have one on deck for Kiri:moto as well.
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One of my concerns is that you are out of the standard electronics, but if I got an xpro5, I am not seeing support. I am an engineer (manufacturing), but I really don’t want to become an expert in all the minutia of this on my own, it would be nice to follow instructions. Maybe I missed them somewhere.
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Electronics are very difficult to get right now. We are on the tail end of supply chain issues, shipping issues, chip shortages, Christmas, and China’s longest holiday of the year. I got everything that was available to me and just sold out yesterday.
We support a slew of boards. If you want to choose something other than one of those boards, you can select something similar and use our firmware to use as a starting point for your own.
Marlin Firmware - V1 Engineering Documentation , Here is a list of our 37 precompiled and pre-configured firmware.
If you are not interested in doing your own firmware I suggest buying the exact boards we support for your project, either wait and get them from me or grab on a marketplace local to you. From there it is just a matter of flashing it, on some boards that is just copy and pasting our files.
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Tell me about it. I have components i need that are 200+ weeks out. It is crazy with some of the lead times!
To get the endstops I have right now I bought out digikey, mouser, and then found a bunch from some other shop I had not heard of. I hope by now they have all recouped. I am hoping this year is smoother. I feel like places are starting to catch up.
You have to admit, the supported boards section is some flavor of Rambo, some flavor of SKR. I suppose if available, they are inexpensive, which is the point. If they are not available…
Or ramps. What boards do you suggest we look into further? What is wrong with rambo, skr, or ramps? In terms of availability they are normally available when the world isn’t so upside down.
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That looks pretty good in a tight package. But it only has 4 drivers. So no auto squaring on 2 axis, even if the sw supported it.
I do wish there was a slightly smaller package in a tidy case like that. Even at $210 (I couldn’t see if that was the final price, it wasn’t in stock where I found it), something like that has appeal.
2x auto squaring, screen/sdcard control, support for as much CAM software as possible, TMC drivers, open source firmware (for flexibility), multiple manufacturers of compatible boards. Those are the features that keep pulling us back to Marlin and 3D printer boards. A 3D printer is just a CNC with an extruder. The boards work for what we do.
Ryan’s stock does ebb and flow. But he never offers any boards he doesn’t have in his garage. No preorders or backorders. Ships usually within a day. You can sign up to be notified on stock and it actually works that way. It’s generally pretty fair, but some individuals can get stuck missing out, or spending too much time trying to hit it right on. Sorry if that is you.
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Ryan,
With margins being (whatever) they are, I think that stocking 10s of a controller might be too much for the cashflow. In normal times that would not be needed.
While it may cause a bit if distress for the newest buyers, I think trying to meet the norm is better than trying to always be prepared for the extreme cases (which we have been experiencing).
Mike
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OK, I’m taking a big deep breath here.
As a complete newcomer, I didn’t have a clue. Two years later I have some clues but not enough to make an objective picture. For me the choice was simple - the Rambo came into stock and the others didn’t so that’s what I went with even though the “other” screen looked way more cool.
If your objective is to give lots of choices in boards and provide support for time then fine, continue this discussion. But if you are truly trying to simplify your inventory and life generally pick ONE and run with it. OR two if as before, that is the best way to overcome supply issues.
Truly, as an ignoramus, trying to choose between two boards was an overwhelmingly difficult thing to do. I still haven’t quite figured out if I can fit a laser later or how to fit endstops. If a better option bobs up that ticks more boxes then roll it out as next year’s model.
More than one option means difficulty in documentation, and causes confusion where there should be none “I’m sure I read somewhere that I have to flash the board in this way…”
If someone wants to buy a Pineapple because they’ve done the homework and think that it will do the job - great, because that’s all part of the spirit of the MPCNC thing.
Let them go to the Pineapple farm, buy one and hopefully when they’ve got the bugs out they can provide some level of support via this place for those who think they want to do the same. Innovation is wonderful, and experimentation is to be encouraged, but please don’t let us confuse the beta hardware line with the stuff that’s actually in store.
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Thanks for the feedback.
I think I am sticking with just one flavor of BTT board for now. The expandability, ease of “flashing” if you can even call it that, and the headless option are all adding up to much easier to support and hopefully I can get the price down a bit.
The other firmware options will stay available for the foreseeable future. Like I said good starting points for people that want a different board.
I am getting emails and some of my vendors are back from vacation so I am going to do everything in my power to bolster the inventory.
And…still working on the to-do list. Dealt with more domain stuff the last couple days. Google stuff. Monday or Tuesday I will be ready to swap the docs over. Jeffeb3 helped set us up for success on that one.
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Thanks to you both for that - I’m a bit otherwise occupied at the moment, but just you wait! 
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Speaking of I need to get that Kiri:Moto guide you made live and add it to the menu.
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