Help sourcing a mill spindle

[richdon]

I folks. I purchased a mill drill a while back, looks like an RF25 or 30 clone. The brand is Power Maxx ,machine-Canada and it is labeled as a drilling and milling machine Mode No: 1-030-025. The spindle is crooked. By crooked, I mean I can see the tool wandering in a circle when the machine is running. It has too much tool runout, I have changed the bearings and they are smaller then the rf clones I have seen. They are: bottom spindle bearing 30206J and top spindle bearings are 30205j. The column is also smaller being at 3 or 3.5" in diameter. Anyone know where I could find a spindle for this thing? My spindle is an MT3 taper but was thinking of maybe buying an R8. Any help is appreciated.
Don

 

[markba633csi]

You might could just straighten the one you have unless you have determined that it was machined wrong and has
uncorrectable runout

 

[richdon]

I think it was bangrd somehow by the previous owner. This is my first mill and I read that runout should not be greater than .0002". Besides, I wouldn't know how to straighten it so it would run true.
Don

 

[Radials]

Have you ruled out the collet holding the tool or the tool itself if it has an integrated MT3 shank?

 

[richdon]

I took everything apart yesterday night. The spindle is definitly crooked, I measured it in the lathe and on v blocks. The bend seems to be in one direction with a max of .027". I am making a drawing of the spindle to compare what is readily available. I found some on little machine shop website but they all fall short lenghtwise by 70 mm. If I can't find anything, I will try flame straightening.

 

[richdon]

Well, I got it to .002" in V blocks, heating and quenching. I know you should not have more than .0002" but, that's the best I can do. Will see how it goes once I have mounted and running a few end mills in it. Hoping for the best.

 

[Advil]

If you've got it down to .002 could you rotary tool grind it in place to within a few thenths?

 

[tq60]

Post some photos of the spindle by itself and in the v blocks.

Lay a pencil where maximum bend is.

We straightened cam and crankshaft back in the day, used stress relief to move them.

0.002 is still a bunch, but can be removed.

You need to determine where the "bend" is located then relieve stress to straighten.

Show photos first.

Sent from my SM-G781V using Tapatalk

 

[m1kemex]

I have an RF40 clone. I got it cheap because the rack on the quill is broken. I've never bothered to fix it because I have on top of a different machine that has a knee. But lately I've been thinking about finally fixing it and after a little of research, I found a seller on Aliexpress that offers replacement spindles. You can get the complete quill with spindle and bearings, but you'll have to be extra careful to measure everything because those are need precision fit.

I think it was $200, but I haven't purchased anything yet.

 

[richdon]

I can't post photos because I did not take any except 1. Now the mill is all reassembled.
m1kemex: I would be interested to know the name of the seller. I have been browsing Alie but found nothing close.
The dots in the picture along with the numbers indicate in thousands how crooked it was.
Don