[gd.marsh]

The splines are in there .. they just don't go to outer ends of the sleeve.

[BobWarfield]

Very cool belt drive conversion!

I'm planning on doing a single piece pulley and spline driver for my IH mill. I do like the v-belts.

You're very close to being able to set that up so you can slap a couple of levers or hit a couple of air cylinders to change gears. That's the way Fadal's change ratios.

Some notes on how to do it on my web page here:

http://www.cnccookbook.com/CCMillBeltDrive.html

Gonna have to get to work on my own belt drive soon. Tired of the slow speeds and especially of the gear oil leaking down onto the work piece. That stuff sure is stinky when it gets hot!

Cheers,

BW

PS There's dimensions for the spline on my Gen 1 IH mill on one of my spindle belt drive pages. I don't know if all the RF-45's use the same splines or not.

[gd.marsh]

Bob,

You're right, the speed range changer wouldn't be that hard to implement with this setup. Certainly something to consider while fabricating the motor mount.

Your website has been one of my favorites since I began my research to build a CNC Router a couple years back. There's a thread on the zone at: http://www.cnczone.com/forums/showthread.php?t=95807

Once bitten by the cnc bug I just had to have a cnc mill .. who knows where it will end?

Gary

[mattmark]

Bob,

Your website has been one of my favorites since I began my research to build a CNC Router a couple years back. There's a thread on the zone at: http://www.cnczone.com/forums/showthread.php?t=95807

Once bitten by the cnc bug I just had to have a cnc mill .. who knows where it will end?

Gary

Nice cnc routing table - that's definitely the next machine on my list.. and go figure, i want to make some guitars too!

Matt

[gd.marsh]

Got the spindle all tore down .. Ordered new Nachi A/C bearings & some Kluber spindle grease. Also decided to follow Tormach's power draw bar design for taking the stress off the bearings ..

I threaded the top end of the spindle & made a flange that screws on, then gets locked in place w/ set screws .. the air cylinder will have some up/down float .. and when actuated will pinch the Bellevilles by pushing down on the drawbar & lifting up on the flange. We'll see how my version of it works out.

Right now I've just got the head sort of 'mocked-up' so I can design my mounts for the motor & cylinder ..

[BobWarfield]

Love the pix.

Where did you order the bearings from?

Best,

BW

[gd.marsh]

VBX .. I got an advertisement from them mentioning they now carry Nachi bearings so I went for those. VBX is sort of light on information, but figured the Nachi's would be better than the run of the mill China stuff.

By the way, thanks for the lead on the Kluber ..

gd.marsh

Oh sorry, I mean VXB!

[AiR_GuNNeR]

GD,
With the flange on the spindle, I take it that you don't plan on using the quill feed any more correct? I hate the way the quill shifts when you lock it in place.

[jalessi]

gd.marsh,

Please post the bearing part numbers and sizes.

Thank You

Jeff...

[gd.marsh]

Air_Gunner
You're right .. the quill will be fixed and solidly locked in place.


Jalessi
7207 Nachi A/C - 35x72x17
7206 Nachi A/C - 30x62x16

[gd.marsh]

Feels sort of like Christmas ..

Packages showing up almost daily .. but today the TTS tooling showed up.
Very Cool! - Should be sweet with the power drawbar setup. Felt like a kid opening everything up and checking it all out. Now all I need is a CNC machine to use them on! Aside from checking runnout I doubt that I'll even mess with it on the manual machine ..

Once the spindle bearings show up .. should be able to get the head all back together and move on to X,Y,Z!

[gd.marsh]

Finally got some time to work on the machine again ..

I'm close but not finished with the belt drive conversion. The plate the motor mounts to took me a long time to make with the rotary table. (way too many mistakes, I'll have to make a new one when I can CNC it!)

I'm going to finish the power draw bar when I can make the mounts via CNC as well.

Got the spindle all put back together with the Nachi A/C bearings and the Kluber grease .. Should be able to complete the belt conversion this next week and move on the the axis ..

[gd.marsh]

Hooked up the VFD tonight and spun up the spindle ..

With the freq. settings on the drive set for 10hz min & 140hz max .. I measured from 270 RPM all the way up to 8,000 RPM @ the spindle!

After some break-in time I ran it @ 8K with no load for almost an hour .. Maximum measured temp @ the spindle itself was 114 Deg-F with 140 Deg-F @ the splined shaft bearings. It dawned on me that I had not re-packed those bearings, so I'll dis-assemble, clean & re-pack them with Kluber grease & see what I get then.

I believe it's going to work!

[AiR_GuNNeR]

Thanks for keeping this thread going GD. This has been a great read so far. I'll be real interested to see how much difference the repacking makes. Where did you get the Klubar grease? I hear that's the cats meow for bearings?

[gd.marsh]

The grease came direct from Kluber ..

https://www.klubershop.com/search.aspx

I sure hope it makes a difference .. $$$$ wow!

[BobWarfield]

gd, that sounds awesome. 8K rpm will be sweet for aluminum.

One thing to think about is how will you monitor the bearing condition? Check the temp seems like exactly the right thing to do. Just seems like its something that ought to be done quasi-regularly to run at those speeds.

The concern would be how well will the Kluber grease stay put in the face of coolant and what not, though it is definitely designed to hang in there.

I wonder if there is some cheap way to put a temp probe on the bearings?

Cheers,

BW

[gd.marsh]

I've got to say it was a little scary when it first spun up to that speed ..

I'm not really worried about the Nachi's .. I believe they are rated to 11k.

I think I may just see if I can find some replacement bearings with a higher speed rating for the splined shaft.

I believe there's enough cast iron surrounding those bearing to prevent any flying objects in the event of a failure .. but I would rather not test that theory either!

gd.marsh

[mattmark]

7207 Nachi A/C - 35x72x17
7206 Nachi A/C - 30x62x16

Hey Gary

8k sounds awesome - btw, i forgot to ask - which models of the Nachi's did you end up getting from VXB?

Matt

[gd.marsh]

Matt,

The ones you included in your post are it .. Go to VXB and look in the Angular Contact section .. find the Nachi bearings showing the numbers you have and that should be it.

Ran it for a while again this morning & decided to just put in better bearings & be done with it. Just ordered a pair of deep groove Nachi's for the splined shaft w/ 11k RPM rating .. @ $10.00ea = Cheap Insurance!

Bob W's idea of a temp gauge is interesting .. I'm not sure how to accomplish it though. I'll probably just check the temp with my little hand held device frequently at first until I'm confident it's going to run at a comfortable level.

gd.marsh

[mattmark]

Matt,

The ones you included in your post are it .. Go to VXB and look in the Angular Contact section .. find the Nachi bearings showing the numbers you have and that should be it.

Ran it for a while again this morning & decided to just put in better bearings & be done with it. Just ordered a pair of deep groove Nachi's for the splined shaft w/ 11k RPM rating .. @ $10.00ea = Cheap Insurance!

gd.marsh

Hey Gary,

There are a few options: for the 6206 Nachi, there is a $16 version all the way up to $230. After the 6206/6207, there should be some more letters in the model? How much were each?

So in total, you're running a 6206+6207 for the spindle and an additional 2 deep groove for your spline adapter/pulley?

Thanks

Matt