June 14, 2016 at 7:39 am #13647
First off thanks for this amazing project!
Have finished my build of the MPCNC just recently and need to decide on a spindle. I am in the Netherlands and need something on 220V. Speed control is something that I want incoorporated. The makita and dewalts were only available in 110V options and quite expensive to get here.
So up until now I have got 2 options in mind;
a chinese 0.8kW air cooled spindle controlled with a VFD inverter; from ebay
a Foredom SR-series flexible shaft motor, genuine one not a cheap ripoff
i’m thinking the spindle/VFD is nice because it’s a dedicated machine specifically made for the job, has a lot of different control/monitoring options. Downside is that I don’y have any guarentee and it could be any quality, might not last for a long time
The foredom is good because the handpiece is very light so the mpcnc isn’t stressed because of weight. (Or is it better to have some weight? I guess there is always a tradeoff? Bit more weight helps with milling but is more destructive to the machine?). Also good are warrenty, servicable parts and a trusted quality. Downside is higher price and it has a lot less power (125W).
So I kinda decided to go for a spindle+VFD for now, ordered & received last week. But I realized it was a lot heavier then I thought: around 2.5kg or 5.5lbs.
So I wanted to ask some people that have actually used the MPCNC what your thoughts are on spindle/tool weight. Do you think the 5.5lbs spindle is too much? What about a super light tool like the handpiece of a foredom?
My frame is quite big (78x78x15cm) because I figured I can always scale down a bit. I would like to do different stuff with it, maybe milling some woods& platics, but mostly aluminium faceplates 2 or 3 mm thick and, if it is accurate enough pcbs. A 3d print extruder is also on the way.
Allright that’s it for now
Cheers, marcelJune 14, 2016 at 7:54 am #13648
The weight will be fine, I can’t believe that spindle weighs so much. We started this whole thing with the flex shaft foredom and it does work well but it is expensive and lacking power.
Your frame is large to want to do aluminum and pcb’s both of those I would recommend as small a frame as possible. Wood and plastic, no problem, but metal and pcbs are two ends of a different spectrum. For pcb’s I’d say the foredom would be best, Aluminum the spindle for sure. It is a multi machine but you are definitely going to the extremes on all levels, large build volume, heavy tool, hard material, and super precise pcb’s. Not saying it can’t be done, just take you time to set up your paths and get your feeds and speeds correct, Let us know how it goes.June 14, 2016 at 9:11 am #13652
yeez, fast reply: thanx for all the tips!
Allright i’ll set it up with the spindle i have then. i am saving up for a foredom anyway because i think it’s a nice tool to have on it self
About the weight of the spindle, yeah i was a bit surprised too, the “datasheet” that came with it even said 3.5kg but on my scale it says 2.4kg
I’ll be focussing on milling aluminium first, pcb’s later, & i will of course let you know how that works out with this spindle.
About the size; I kind of figured it is too big. The reason i built it this size is that i wanted to be able to occasionally mill a 19″ frontpanel. But of course this is normally not a 19″ square. Would you reccomend only shortening one axis to get improvement for instance leaving the x rails at 78 cm and shortening the y rails to around 50/40cm ? Or better to keep it square?
and of course i undestand there are practical limits and was allready thinking if all works ok and i have the possibility of printing partsi’ll make some dedicated mpcnc’s. One that is small and more precise for the pcb’s for instance..June 14, 2016 at 9:14 am #13653
I would say try it out as is, if your tolerances are within reason keep it as is. But if you find you have issues shortening one axis is definitely the best option. I’m in the same boat. I need it to be big enough to mill the 15×15″ panels for the mp3dp, but in my case I think I will just build another small one if I run into issues.
You must be logged in to reply to this topic.