Buget Warco Major 5 axis conversion

[Tweaky]

Greetings to all, and thanks to many.
I have been researching for a while now, and found many helpful and informed comments on MYCNC........ Many thanks for a great site and comunity.

I have for many years wanted to have a cnc mill to make prototype parts, and possibly manufacture small runs to sell.

After many failed purchace attempts on Ebay, I finnally bought an old Warco Major, made in Korea, and fairly poor condition, but at £125 I could not refuse.
Found a man with a van (and tail lift) to deliver it for £40.
Built a stand from 4x2.
I stripped it for inspection ...... ooooo! ..... it looks like i was used to cut stainless mainly on the Y axis, no covers for the ways and lots of swarf embeded in them.
There was a dip in the middle of travel, of approx 7 thou!, so I spent many, many hours with stones and then lapping paste and it is down to 1/2 thou dip. (just read of an enineering company in Bedford, who will recut the ways for £30 ish) ....we live and learn.

The X axis was OK.
Quill OK
The spindle bearing are fairly worn and get hot at 2500 rpm, will replace those later.
Motor (2HP single phase), was replaced with a 3 phase 2HP for two reasons:-
1/ the single phase motor was the source of much vibration and fettling did not improve it (un-even air gaps)
2/ I already own a VFD.

For the conversion, I gleaned much of the spec. from here, Robin Hewitts post, but combined with info from Gary at Zapp and others.

Bits:-
Ballscrews where purchaced from China (sorry to the English Companys) for £92 inc post and end machining. That is 2 x 1605 screws 400 and 600mm long, 2 x ball nuts + machining. They are single nuts and C7 rolled screws.
Direct drive size 34 steppers (4.5 nm) from Arc Euro for X & Y, & A, size 23 (3 nm) for Z & C. (forgot to say, it is going to be 5 axis).
Z screw from an aircraft breaker, (a flap screw I think) anyway it has a 1605 screw and rotating nut.
Driver was one of the cheap 3.5A 36V, sorry 1.5A 24V boards from Ebay, but more on that later.
Mach3.
Old 2.8Ghz computer and a 15" ELO touchscreen from a skip(thanks to my partner) which I repaired.

The work:-
Made blocks for the nuts, used the original bearing blocks and used a pair of angular contact bearings on each ballscrew, with the opposite end floating.


The motor mounts


Motors on


Having mounted the motors, I was keen to try it out, so I connected the motors to the driver 36v 11a PSU at min voltage of 32v and hey presto!
Chuffed with my progress, I came indoors and did some more reseach.
I read page after page saying that the driver board I was using was pants! Most blew-up at 30v or more (I had run mine at 35v with no problems {35v is max input for the 5v reg.}).
More research, looked at modding the driver, then decided this was a waste of time and money. So i bit the bullet, phoned ArcEuro and ordered 2 x 9a and 1 x 4.2a drivers (for X, Y & Z). Bought an opto board from ebay, also found some IP67 micro switches for the limits (£25 for 5)
Using the 36v PSU (can go to 80v on the 9a driver) connected up and spent many hours, initially without any movment from the motors, then to one direction only (9a drives have switch for step/dir or CW/CCW orientation wrongly described) and finally working well.(Required 6uS setting in Mach3 for both step and dir.)
Since this is never going to be hyper acurate, I have used 2000s/rev = 400 steps per mm.
It runs at the maximum Mach3 can output in 35Khz mode which is 5250mm/min. so I am happy with that.

Made sone covers for the ways, and fitted X & Y limit switches (one each).

Found another bargain on Ebay, my fourth axis, apparently from a Swiss gear cutting machine.


Boy is it heavy, must weigh 40-50 kilos!, bit worried about the balance of the table, but with the trunniun table and end support it should be OK, I hope!?

OK enough already, I will add more a I go.