What a fun project this is. Never used a CNC before, so have quite a bit to learn, but these forums are great for info, so thanks everyone! I’ve had a 3D printer for about 2-3 years now, and saw the MPCNC on thingiverse years ago while looking for pointless things to print, and thought “man this would awesome” but thought it would be too difficult. Well, I’m glad I finally gave it a shot!
I ordered the rambo dual endstop kit from the v1 shop, printed all the parts myself. The build guide was perfect, and other than getting frustrated trying to make sure everything was square 5000 times it was not bad at all, quite enjoyable building it.
I did go larger than recommended, with a work area of 2’ x 3’ (actual working area ended up being x:580 mm y: 885, with a small buffer). I ordered 1" OD stainless steel tubes in hopes it would compensate for any rigidity issues. Just did a tiny test cut nothing else so not sure how true that will end up being.
I still need to do cable management, print an electronics enclosure, wasteboard, dust collection, etc etc, but I was too excited and wanted to cut something! I did a few different sized squares (10mm, 50mm, 100mm) and a 40mm circle, and my last name for fun. Everything came out exactly 0.13mm (both axis) smaller than expected, regardless of square size, so I’m guessing I probably set my bit size incorrectly since it didn’t scale with the size of the squares? Used Estlcam with 1/8" upcut (3.18mm is what I put in software).
Costs:
V1 Kit with LCD and rambo board: $381.14
Filament: ~$40
Stainless Steel: $329.68 (this hurt price-wise, from speedymetals, tried finding local, but… Nebraska…)
Makita router: $119
Total: $869.82
Welcome to the mad house!!
You just open a new hole into the endless rabit hole of possibilities!!!
Make sure you have fun creating things, and enjoy making them!
Hehe, it is very exciting getting your first cnc cuts going isn’t it? 0.13mm error is very good for a fresh untuned build!
The fact that the parts are uniformly smaller on xy is telling. Could be steps/mm, but more than likely it’s flex. 3.18 is close enough to 3.175, and you don’t want to compensate for this error using bit diameter, because that will cause issues with inside/outside features. Are you doing climb, or conventional cut? Conventional is generally avoided on these flexible rigs, and often will result in undersized parts. With climb the flex makes parts too large, which is easy to fix with finishing passes.
I left pretty much everything default in the EstlCAM settings page and only changed what was explicitly listed on the ‘EstlCAM Basics’ page. It was set to conventional.
I also just realized I did not select a ‘finishing tool’ and just left that blank. Does that matter? When I hover over the finishing allowance it says this:
“If no finishing tool is selected (see above) this field leads to according over- or undersizing of the object… Otherwise it defines the machining allowance for the roughing pass. In this case “0” will automatically be replaced by 5% of the tool diameter.”
5% of 3.18mm is 0.159mm which is basically what I was off by, or am I reading that incorrectly? So much to learn! (more for curiosity and how the software works, I’d never notice something being .13mm off lol)
I don’t use estlcam, but that description is clear. Do you have 5 entered in that allowance box? It says it only automatically uses 5 in place of 0 if a finish tool is selected, which you did not select. If so, changing that to 0 would fix it.
Looks great! I’m building one around the same size and I’m also in Nebraska (Omaha). I’ll likely go with SpeedyMetals for the stainless as well. What gauge did you order? Seems like it’ll be easier to order it long and cut it down at home. I’ve used the Metals Supermarket in Omaha before, but their stainless prices are insane (3x SpeedyMetals).
I’d planned to print the parts in carbon fiber PC, but everything I read says plain PLA is best. I’d forgotten how easy this stuff prints!
This is what I ordered: 1" OD x 0.870" ID x .065" Wall 304 Stainless Steel Tube (Tubing), Annealed. I ordered it cut to length, but in hindsight prob should’ve just cut it myself and saved a few bucks. Took about a week (5 business days) to ship after I ordered it.
