Thread: Mechanism to increase spindle speed? Adapter?

Damnit guys, dontcha' hate a tease? Come on Zahnrad, share the ball thing with us.... ..... please....

Bob

Okay, later though... miles to go before I sleep...

Think 3 1" hardened balls, one ER16 extension spindle, a couple of
races from a 2.75" angular contact bearing, and some Aluminum round stock.
Couple smaller bearings for alignments, and viola~! They're really that simple.
The balls ride on the outside angles of the races, and simultaneously contact a groove (with 45 degree chamfers) on the spindle.
A reaction rod keeps the outer housing from spinning, like a tapping head.

Easy piecey.

Wow, friction drive, who knew, well besides you and the designer.... Thanks.

Bob

Yep. You got it. (with apologies for not thinking to call it that, earlier)

Looking at it, I really don't see why one couldn't make one for relatively small dollars.
I did think to take hardness tests while I had it apart and nothing was more than 46Rc, if I recall correctly.
Looking at it, it would be about the same difficulty as making my rotary broaching tool. Very simple.
Probably cost about the same, too...

That said, referring back to the original post, it would be reasonably simple to lash up a router head to the B'port's spindle and use that instead of the mill's motor.

Have fun.

Thanks Zahnrad!

Since I already broke my word to stop this hijack, I'll just stick these last two photobucket links in here, rounds out where the pattern's gone, between the router mounted on the mill and the 2 castings in my last pic. Posted for inspiration to others who've wondered if they could make their own castings, sure you can! From drawing to mounting part on machine and everything in between. Saves tons of chip and cleans up the aluminum/brass scrap pile. With my smaller silicon carbide crucible, even iron.

Note Pontiac Firebird front disk brake, (and "classy" high dome, chrome plated acorn lug nuts, I had 'em) on crane pivot, just below 10' jib, (20' reach, includes foundry-shed 4' (2, 24") door for heavy stuff like the table saw) with red over-center brake handle at waist height. That and the crane control box make large castings an easy one-old-man, (73 next month) op. Over 200# of Petrobond molding sand in each mold, had to build the crane.
http://i102.photobucket.com/albums/m.../Shopcrane.jpg

Click on pic for a short movie of the pour. The clip is expandable to full screen. The combination mold weight/molten metal-chute, made from 10GA sheet and lined with 3,000°F refractory, as is the 5/8" wall steel crucible, whose 1" pivot posts were pushed through holes in the steel tube and welded inside for safety, then of course covered with the lining.


If there's any further interest on this theme, it WILL be a new thread, promise...... again.....

Bob

Bob,
Whattaya mean, further interest? Of course there is. Get that thread goin!

Umm...no safety glasses, no leggings? My foundry professor got molten aluminum in his shoe. His helper said it smelled like steak cooking. Just a thought.

Tom

Originally Posted by Robert Campbell Jr.

Wow, friction drive, who knew, well besides you and the designer.... Thanks.

Bob

McCulloch/Paxton centrifugal supercharger speed-up drive - last seen on Studebaker Avanti... FIRST use not known to me, but perhaps Lady Ada Augusta Lovelace may have had her delicate hands on input to one suspect machine, and Vannevar Bush on another much later....

Bill