[IMG]Tree Mill after retro fit[/IMG] [IMG]parts[/IMG] Here are pics of my recent PC operated retrofit . The mill is a 1979 Tree ( was 2 axis)that sat in a Defense Contractors storage room for 16 years ( control went kaput ) I bought as salvage at an auction,used a few years as a manual mill. After retirement I rebuilt the head ,ball nuts and shafts etc, but an accident made it hard to operate from a wheel chair manually, so I retrofitted using MTC servos,servo Amplifiers, encoders and Desk CNC motion Control Card and their software. I did add Bayside
( Parker) Planatary Reducers and with the belt drive gives a 20:1 reduction. The 20:1 relates to 80,000 steps per inch for excellent resolution.I handled the Z axis with a double reduction jack shaft and drive the quill through the rack and pinion.The Z is only 3200 steps an inch, but accuracy is ok. I ripped out all old wiring, electronics, relays etc ( That was fun !) and started over.At least I understand the system and could trouble shoot if a problem comes up.
We built a plexiglass enclosure that opens in front , and if need be can be removed with two allen screws. Does help keep the coolant in and returing to the pump sump.
I used an AC Tech 2 hp VFD with the remote control...That works good ,in fact have the spindle speed above 4500 now.This means I can dedicate one of the phase converters to the 20 inch Bandsaw. Considering using a 10 hp VFD for my Pratt&Whitney Lathe as the 12 hp idler plus the 10 hp lathe do draw a bunch of amps,and from testing amp draw before and after the VFD, there is a substantial improvement.
Just started using Vector CadCam and have been able to make some decent parts (pictured).I'm a real computor Klutz so I had to"go back to school"(Microsoft XP for Dummies,CNC for Beginners and Dummies ) and ask a lot of questions...both Fred Smith at IM services, who supports & sell Desk CNC and Vector, and Scott at MTC have been very helpful & prompt with replys. Both have had to talk me through some self induced problems , and with out laughing
Accuracy after warming up the machine is : X= 0.0003 ,Y=0.0007 and Z=0.0015.
I had a terrible time understanding "cutter Comp" so scrapped some complicated pieces and had to start over , even with the drawings. I edit the generated G code for tool changes by sending X out past the part stock and coding in a pause ( 60 seconds)
twice now I left Z down in the part and rumbled out at Max G00..One I had already cut to 3/4 inch...That made some noise as it ripped out 3/4" with a 3/4" cutter at 50
IPM.. not good.Before hooking up limit switches, I banged my 22 year old Heidiham ( or how ever you spell that German word ) x axes DRO sender in the back of the table. Naturally, they do not supply any parts or replacements for something that age, so had to buy a new DRO. I was able to use the Y Axes sender to locate the knee accuratley,as I motorized the knee.That Tree knee is real heavy,just could not raise or lower out of the wheelchair.The knee is not a part of the CNC Controls, just a convience to flip a switch and raise and lower.
I did find out you can not manually move X-Y very well ( with power 0ff) as cranking back into the 20:1 reduction is like being stuck in syrup. With the power on and the servos holding I can not move the X-Y at all, so all location is done with the mouse.Ok after you get used to it, but still find my self starting over to the handle to tweak it.
Cost with the mill (no moving costs included) has been $5500.00, but does not include the Vector CadCam software, and I got everything with that.On- a- count of its a "project", I did not keep track of labor hours spent, and had to hire a next door neighbor to help with some heavy stuff.Wife helped with removing/replacing the leadscrews and thats NOT reccomended for a happy marriage,by the way.
Now in the planning stages of building a CNC plasma cutter ,will use the same set up and software...keep looking at that 12 by 30 Pratt-Whitney lathe for possible CNC too.
It has been fun.