The Home Machinist!

Finally got around to making some bushings for the left side of my Lathe spindle to support longer pieces of bar stock. My spindle is nearly 30" long from the chuck jaws to the fitting on the opposite end that the collet closer attaches to. I made four bussings for now to support 1/2", 5/8", 3/4", and 1" bar stock. I cut an O-ring groove in them, installed an O-ring, and knurled them so they just plug in and pull out. They seem to work just fine, so I'll make more sizes as needed!

I've seen adjustable spiders used, but I believe this is easier and quicker to change sizes as there is nothing to adjust.



Glenn

Nice design. Simple AND inexpensive. My kind of tooling.

Greg B.

My compliments on your knurls. I have no use for anything less than those generated full depth.

Great idea on the bushings. One I should duplicate in the future. Even when long stock is not a danger, running off center has a way of manifesting itself in the cut. That's a slick way to accomplish the task, and will repay itself many times over if you ever run a production lot of long pieces.

Harold

Supper cool!!!

This one goes goes into my "To Do" list.

Thanks for sharing

Glen, looks good, and might never have a problem, but I would not trust them with long stock at a very high rpm. It could whip if the plug came out and that could get ugly. You will have to be the judge, but I would at least use a set screw.
James

James,

I had the same concern and appreciate you bringing that up!

I put enough interferance fit on the O-rings that it takes both hands and a twisting pulling motion to remove the bushings. (hence the knurl) I left one in the spindle for a few days and nearly had to pry it out! The tendency for such a bushing to escape is nill as the bar, bushing, and spindle are all rotating together and the bushing bore is .005" larger than nominal to keep bar to bushing movement to a minimum. A little common sense is also required as far as how much bar is to protrude past the bushings

I keep having visions of a pneumatic bar feed system. The next step though will probably be a leg a couple feet away from the headstock with a large bearing in it that will accept the same bushings to be used as a rotating bar support for longer lengths when using collets and my turret.

Since we're on the subject of turning bar....When making small numbers of parts with the chuck installed, I prefer 1' to 2' lengths of bar and I work both ends of the bar. Especially when a second operation, such as hexing, flats. or cross drilling is concerned. I'll turn both ends, then put it in the Super Spacer for drilling, hexing, etc, and then part it off in the lathe or occasionally the cold saw. I'll use two or three short bars to accomplish this much quicker than one long bar.

Glenn

Edit: Usual typo's!

Logan made a form of turret lathe.... regular lathes with turret attachments and lever cross-feeds.

To go with them, Logan also made floor stands with a loop at the top to hold the stock from whipping. Good when you have a 15 foot section of 0.250 stock.......

Wouldn't be very hard to make something like that if you have any significant amount of stock hanging out.......

Glen, sounds like you got it covered. Just did not know If you had thought about it.
James

Nice work, Glen!


Beats the heck out of mine:





And, yes, the cork does work loose sometimes, but after one close call, I NEVER leave more than a few inches sticking outboard.

Holy Cow...

I got a step ahead of Frank

Glenn