I’m currently evaluating a MPCNC build as my “this years DIY project”. The plan is to be able to mill & engrave aluminum and play around with steel (I know there are different types of these). Some wood working, too, but just because it’s possible
Size-wise I’d aim for a 320mm x 250mm x 50mm build (12.5"x 10" x 2").
Now for aluminum I’m under the impression the Kress/AMB 1050 FME-1 should be well suited. But for about the same money I could also get the Suhner UAD 30-RF (which is basically a UAD 25-RF with extended speed range).
They advertise it to be suitable for steel, which I think is quite nice, and it goes from 3,500 to 30,000 rpm vs. “only” 5,000 to 25,000 for the AMB; but it weights 2.85kg or 6.2lbs vs 1.7kg.
Does someone have experience with that tool? Would you recommend trying it out, or just go with the Kress to avoid having too much weight/flex on the Z?
I was checking options (in Europe) and found the two Kress/AMB to be quite popular with MPCNC builders - and the third (in the topic) as an interesting alternative from the linked CNC machine manufacturer above:
Kress/AMB FE-1050 FME-1: 1050W, 1.7kg, various rpm variants: 5k to 25k, 10k to 29k, 3.5k to 25k, ~ 240 to 250 Euro (depending on variant, maybe 200 for some)
Suhner UAD 30-R: 1050W, 2.85kg, 3.5k to 30k rp, ~300 Euro (maybe 250)
I [think I] saw you've also tried steel, Ryan. So power-wise suppose I can go with either Kress, I suppose - assuming the internal bearings can handle the forces; the Suhner is explicitly sold as "suited for steel milling".
Regarding the RPM bands: Which one would you recommend?
Nice to have, in that order: Steel, Wood, Plexiglas, maaaaaybeee Plastics
Want: Aluminum
The cheapest “brand” alternative I found was a Makita RT0700C, 710W, 10k to 30k for 120 Euro, but usually not sold/used for aluminum - at least from what I could gather. And I don’t want to break & throw away a 120 Euro tool and then get a 200 Euro tool instead ^^"
Remember that power isn’t really as much of a factor as you may think. You could do steel with a really low powered router, just slower than you would with the standard ones we use. A bigger factor is the design and build of the router itself. You want something that is internally rigid and robust. Many of the low end routers will wiggle when you put pressure on them while cutting, which is worse with hard materials than with soft. Either of the Kress machines will be great for your use, unless you want unreasonable speed.
Okay, I was aware of the power, sorry if that was not clear
Rigidity of the motor and it’s bearings is also important, as is cooling (lower rpm -> worse cooling).
@bill: “the standard ones we use”: You mean “we” as in “we, at my day job, where we do professional CNC milling with really expensive gear” or as in “you and me, hobbyists on the forum, doing this for fun”?
I played around with the speed calculator linked in the building manual. I think >25k rpm should not be necessary, but being able to drive down to lower rpms seems to be good (I forgot the exact parameters, but I often ended up with recommendations around 5500 rpm for the harder stuff and 6-8mm end mills). So it’ll be the 1050 for the ability to go down to 5k or 3.5k vs. 10k for the 800. I’ll just get the best value variant once the rest of the CNC is up and running.
I think I will have further questions, especially regarding end mills (so many choices!). But that can wait until I’ve drawn some circles, which means printing the parts, which means fixing dimensional accuracy on my delta, which… well, I guess you get the idea
Thanks for the helpful replies
//edit: Regarding speed: I’d love to to unreasonable fast carvings (<5 minutes?) with up to 30 mm diameter and maximum depth of 3mm into aluminum or another soft metal; but honestly I want to build the MPCNC because it’s possible, not because I need one. If it does some random job in 5 minutes or 5 hours is not that important to me - as long as it can be done.
