Got the chance to do play with a minitech minimill 3 pro

[Fixittt]

I have been working on a minitech minimill 3 pro. Setting up an automatic toolchanger. I have to say WOW. This machine is a TANK! While not light on the wallet. This thing is amazing.

I got contracted to work a couple bugs(turned out to be a broken wire in the control box) out of the system. Needless to say, This machine run soo smooth. While I didnt have the right spindle to actually do tool changes I improvised. I hooked a small lamp to the collet release relay. And made a video of it running thru the tool changes. Small G code to cut a 1 inch line in X and change tools 5 times. Will post the you tube link. I also wrote some toolpaths to tet the control boxes. Long long 3d code to see if the machine will miss steps ect.

I am totally impressed with these machines.

YouTube - mini3proatc

YouTube - mini3proatc

*EDIT* added what issue was found in the control box wireing.
Also tested the minitech front end of mach 3. We also improved a couple features based around the ATC configuration.

[SpeedsCustom]

That is amazing!

If you don't mind me asking? How much did it cost you? Ballscrews, linear ways! Wow, great work. What are your actual cutting speeds? I imagine pretty high...Man! I want linear ways and ballscrews!


-Jason

[Fixittt]

Speed.......
Unfortunately I do not own the machine. I was asked to help solve some issues with it. Come to find out there was intermittent contact with some step/dir wire. Found that some of the wires were actually broken inside the insulation. Re-wired the controller. This is smooth. The machine is setup for micro-fluidics. Really small parts. So I have it setup for higher resolution which limits the top speed. I cut the wood face at 1000 mm`s per minute.

[SpeedsCustom]

True- I looked up the machine, very expensive. Good for high precision stuff...


But for the price you could get a CNC IH mill!

Dang!!!!!!!


With the the broken wires, what was the issue? What was happening with the machine?


-Jason

[Fixittt]

jogging was very erratic

In Mach 3 press the down arrow button to jog Y and sometimes Y would move and sometimes Z would go up. very erratic on all jog commands.

[rc-monster mike]

Originally Posted by SpeedsCustom True- I looked up the machine, very expensive. Good for high precision stuff... But for the price you could get a CNC IH mill! Dang!!!!!!!

This is indeed true - but it is a matter of the right tool for the job. For small parts that require rapid movement, high accuracy and reasonably high spindle speeds, the IH is not the right tool for the job and would be considerably less productive than the Minitech machines.

[Fixittt]

I totally agree with Mike here. You need the right tool for the right job. A bigger mill could be had for the same price. But sometimes a bigger mill doesnt fit the requirments of the client.

I will say that the technology that is in place on these machines is out standing!
The level of engineering is impressive with this desktop machine. When you are dealing with nano machining and microfluidics this machine is no slouch.

I am shipping out the drive controller today back to the client. But the machine itself gets to stick around for a bit longer. So I will be building another drive box and do some more testing. I am actually excited to try some of this microfluidic machining I have been reading about. As per the agreement with Minitech I will do my best to find any weakness with the machine design under these high tolerance demanding situations. But having talked with some engineers in the industry that utilize these machines. It already is a solid performer! I am guessing that I will be hard pressed to find anything that might or could be improved upon.

[Harryman]

You can run them at crazy fast feeds without a problem, depending on materials, cutters etc. I'll normally run mine at 1500 -2200 mm/min with .005" conical cutters in wax. 1/8" end mills, I've had them up to 3000mm/min which is pretty hilarious actually. Takes about 5 seconds to mill a square inch.

Like everyone above mentioned, not designed for big cutters and deep cuts, but they're great for small precision work.

[rc-monster mike]

Originally Posted by Harryman You can run them at crazy fast feeds without a problem, depending on materials, cutters etc. I'll normally run mine at 1500 -2200 mm/min with .005" conical cutters in wax. 1/8" end mills, I've had them up to 3000mm/min which is pretty hilarious actually. Takes about 5 seconds to mill a square inch. Like everyone above mentioned, not designed for big cutters and deep cuts, but they're great for small precision work.

They are impressively capable little mills for their size. I actually have the "big brother" to this machine (minimill 4) with some mods. Even when it had the Sherline spindle and a 1/2 HP motor, I could cut 6061 Aluminum at 60+ IPM with a .25" bit at .05" DOC(I can double this now with the same machine and different spindle). 400ipm rapids are no trouble with a stepper system, either. Like Fixittt said - they are smooth, efficient little machines - tough to find better in this size IMO.

[cadmonkey]

Can you post a photo of the spindle? Is that similar to the HF spindles from homeshopcnc and keling? (http://www.homeshopcnc.com/HFspindle2.html and http://www.kelinginc.net/CNCSpindleandController.html)

[rc-monster mike]

Originally Posted by cadmonkey Can you post a photo of the spindle? Is that similar to the HF spindles from homeshopcnc and keling? (http://www.homeshopcnc.com/HFspindle2.html and http://www.kelinginc.net/CNCSpindleandController.html)

My mill has an x2 head on it now(with a completely custom z axis from the bearing block outwards) - sporting a 2HP motor and 2 speed pulley setup and using Tormach tooling with the z-bot power drawbar. No HF spindle on my machine - or were you asking Fixittt?

[cadmonkey]

Sorry Mike - Yes I was asking Fixitt - the video looks like it is that style ('that' being the links I posted) and those have caught my interest, though price makes me want to research a lot more, get some opinions, and see what kind of applications they are being used in - The pics Fixitt posted look like work that fits what I would like one for - but wonder if they are capable of less detailed, and more stock removal oriented work (assuming the axis carrying the spindle can handle the loads).