7200 Belt driven spindle

[Thorpydo]

Just about finished my belt drive conversion. I'm fairly happy with the results. I've got the option of a 1.8 gear ratio or .72 (7200 rpm or 2880 rpm max). It's easy to change belts, just loosen bolts and slide motor plate forward and off it comes.

The spindle does get hot and I think my next project will be a coolant collar for the lower spindle bearing. Has anyone figured out a way to cool the upper bearing?

People have ordered better quality replacement bearings but I can't seem to recall who or where I saw it. Can someone point me in the right direction?

[BobWarfield]

Very nice!

Give us a few more details.

Best,

BW

[bertmiller]

here are links to threads about the x3 spindle and bearings:
http://www.cnczone.com/forums/showthread.php?t=50760
http://www.cnczone.com/forums/showthread.php?t=45155

i have done a simular conversion but i dont dare to make pully that will make the machine go above 3000 rpm.
my next step is also to find new and better bearings.

does your machine remain stable at speed? wrong belt tension can already instabalize you head.

[Thorpydo]

The way I figure it. . . I'm already looking to buy new bearings. It's not the end of the world if these ones go bad. At least that way I'll know my boundaries.

The head seems stable. It's cutting just fine. The pulleys are a little off axis and it is noticeable when starting or stopping the machine but they seem just fine while it's up to speed.

I wont be making chips til tomorrow. I'll take a quick little video then.

[dwessels]

Thorpydo,

Looks really cool.
I recently replaced all of the bearing on my spindle. I replaced the bearings with ABEC 5 bearings that are supposed to be good to about 11k rpm.

Now I want to speed up the spindle and get rid of the gear noise.
Would you mind sharing your diagrams, or any other info?

Thanks!

Denzil

[MRM RCModels]

Originally Posted by dwessels Thorpydo, Looks really cool. I recently replaced all of the bearing on my spindle. I replaced the bearings with ABEC 5 bearings that are supposed to be good to about 11k rpm. Now I want to speed up the spindle and get rid of the gear noise. Would you mind sharing your diagrams, or any other info? Thanks! Denzil

Where did you buy your bearings from? Mind sharing the part numbers?

[pete from TN]

Hey man very nicely done.....
I am right now in the process of doing something very similar to that on my Lathemaster mill. I intend to use the motor mounting bolt as a pivot and then have a handscrew to tighten things down with. What is the base rpm of that motor? I just bought a brand new 3 phase 1725 rpm motor and a vector drive for my machine and I am anxious to get it built. I machined the standoffs yesterday for it and now I am onto the motor plate. Agian nice work man and play some video of it running when ya get a chance...peace

[Thorpydo]

Thanks for the links. I didn't realize how expensive those bearings can be!

The max rpm on the stock motor is ~4000rpm.

The cut in the video is with a .250" 3 flute carbide endmill. Spinning about 7200 rpm, 20 in/min .090" DOC. aluminum 6061.

YouTube - DSCN0155

YouTube - DSCN0155

[dwessels]

Originally Posted by MRM RCModels Where did you buy your bearings from? Mind sharing the part numbers?

Sure...
I actually called Applied Industrial in San Jose as they are local and I was hoping to pick them up the same day. They had to order them in anyway and shipped to my house.

I gave them the following:

Spindle taper bearing: 32006C (The sales guys said it wasn't available in a higher ABECs rating)
Spindle bearing 1: 6007 (the stock one were shielded, but the ABECs 5 where only available in sealed, which I used.)
Spindle bearing 2: 6006 (the stock one were shielded, but the ABECs 5 where only available in sealed, which I used.)

These aren't the part numbers they shipped, but they were the part numbers that I asked them for and they looked them up and found the ABECs 5 equivalent. I actually got lucky when I ordered, the ABECs 3 stock in their facility had rust damage and the gave me the ACECs for at no extra charge. Seem to remember the 5's are about 3x the cost.

Denzil

[pzzamakr1980]

You know, after having my machine setup to run at 6000rpm for nearly two years, the bearings have yet to fail. I put a coolant plate on the front of the head and around the lower bearings about 6 months ago and they work great. When not running coolant the plates get hot so I know that they are pulling the heat. Turn the coolant on and it does its job perfectly. But even without the plates the bearings lasted two years with no complaint or any apparent ill effects. Also, straight replacements are cheap and there is a seller on ebay who sells high performance bearings for the x3 for a reasonable cost if you care.

[pzzamakr1980]

Also, very nice setup thorp and nice cube.

[Matt McColley]

there is a seller on ebay who sells high performance bearings for the x3 for a reasonable cost if you care.

got a link?