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Denny Nebgen
07-27-2021, 3:24 PM
I have used this mandrel for turning salt shaker pepper grinders for awhile now. Its about 10 and 1/2 inches in length has 3/8-16 left hand threads the whole length except for a little bit at the tail stock end for the mandrel saver to slide over and about 3/4 inch at the head stock end where it's threaded 5/16-18 right hand threads to screw into the Morse taper that it came with. The threads are getting pretty beat up and I'd like to replace it but, for the life of me I cannot remember where I got the thing. It came with 3 sets of rubber bushings and some left hand nuts that allow you to expand the bushings inside the what ever you're turning (in my case the salt shaker pepper grinder kits from Penn Sate Industries) to hold them for turning the profile you want.

I have searched the internet and looked at all the turning tool sites that I have saved but, I cannot find it online. Does anyone have one like it that could direct me in the right direction to get a new one? If not, I'm going to have to make one myself. Was just hoping to save the trouble and keep turning things I want to work on.

Thank you in advance.

John K Jordan
07-27-2021, 5:35 PM
Denny, a picture would help, don't remember ever seeing one. It might be easy enough to make a replacement with rod and a left-handed die. A machinist should be able to make one quickly.

Another option might be to simply use a piece of right-hand threaded allthread and use a nylock nut or double nuts to compress the rubber bushings.

Sounds useful to hold a number of things.

Denny Nebgen
07-27-2021, 8:29 PM
Denny, a picture would help, don't remember ever seeing one. It might be easy enough to make a replacement with rod and a left-handed die. A machinist should be able to make one quickly.

Another option might be to simply use a piece of right-hand threaded allthread and use a nylock nut or double nuts to compress the rubber bushings.

Sounds useful to hold a number of things.


Thank you John for the reply. Yes, I can make another one. I am a retired toolmaker. However, that takes time away from turning so, I would just as soon find another. I will try to upload some pics so you and others can see what I am talking about.461977461978Could only get two uploaded. Can try again to get one more. The one shows just the mandrel on the lathe and the other shows it holding a piece. The rubber bushings expand when nuts are tightened to hold the work piece.

Denny Nebgen
07-27-2021, 8:31 PM
Here is one more showing the mandrel removed from the morse taper.461980
This works pretty well but, the steel used seems pretty soft and not much temper so the threads do not hold up well in my opinion.

Peter Blair
07-29-2021, 9:14 AM
Could you not make one using turnbuckle parts. They come in many sizes and lengths and each has a right and left hand threaded section?

Denny Nebgen
07-29-2021, 4:43 PM
Could you not make one using turnbuckle parts. They come in many sizes and lengths and each has a right and left hand threaded section?


Maybe so. I was tossing that around as well.I might try one using right hand threaded rod simply because I have that here and if that doesn't work, I'll order a left hand 3/8-16 threaded rod from McMaster Carr and some left hand nuts as well. Thanks

John K Jordan
07-29-2021, 7:05 PM
Maybe so. I was tossing that around as well.I might try one using right hand threaded rod simply because I have that here and if that doesn't work, I'll order a left hand 3/8-16 threaded rod from McMaster Carr and some left hand nuts as well. Thanks

Maybe look at what Rubber Chucky has. I'd have to look through my container of his stuff but I think I have a long threaded rod that can be used in a variety of ways, it might do what you need with a couple of thread-on pieces. I think all the "rubber" pieces he sells can be turned to the shape and size you want. I turned some to make ways to hold special things.

JKJ

Denny Nebgen
07-29-2021, 9:58 PM
I made one using right hand all thread for now. I don't know if I'll get to try it out before next week. I have shows this weekend. 462068462069
First shows the old shaft and new shaft as I'm starting to put things in place and the second everything switched over. I did make it just a bit longer. We'll se if it works the next time I set those up.

Dan Hunkele
07-31-2021, 9:27 AM
Hand screw clamps employ screws with both right and left handed threads. Might be a good replacement if proper length and thread size could be found.

Also, may it have come from a buffing system?


https://images.thdstatic.com/productImages/3a9fc79a-e05c-41ec-a40a-03f8dd007f43/svn/bessey-clamps-lhs10-64_400.jpg

Denny Nebgen
08-03-2021, 3:13 PM
I just turned a salt shaker / pepper grinder on my home made mandrel with all right hand threads and everything seems to work well. On a second one now and I think this will work out just fine. If this one wears out, I'll make another. Thank you for all the input.