Spindle adapter for threading jig

[Brice Rogers]

Mark, I thought that the video "As the wood turns" highlighted the value of using CA glue to make the thread form look nice without chip out.

BTW, there isn't a lot of strength or purpose in having real "sharp" threads. If you look up the form of the US national thread specs, they don't come to points. They are trucated (slightly rounded or squared off) on both the peak and the trough. I know that the national thread specs don't apply to the threads that we put into wood and that all we are looking for are two pieces that screw together. But perhaps the logic behind the spec does have some value. I suspect that the reason for the threads being truncated is because there is little strength in the tips of the thread. Also, I suspect that threads that come to a sharp point are likely to look a little ragged (when in metal) or show chipping with wood or other brittle materials. If you want, I'll post a copy of the national thread diagram.

[Mark Greenbaum]

Brice: As a Designer of products for the past 45 years, I am aware of thread configuration. I did use CA glue to strengthen the at best questionable spalted silver maple. And I sanded the peaks down a bit to get the sharp edges off. Remember this was basically a thrift-driven DOE (Design of Experiments). I am trying to keep the cost as low as possible, and achieve repeatable results. It has been a learning experience, as well as a test of my patience and ability to solve problems as they arise. I feel confident that I have come to a pretty good design, that is able to be modified if need be. I have been enthralled with the "screw threads on wood" issue for a few years, and after seeing Dennis Paullus' demonstration at our club, and Mike Peace' video, I felt I could do this, too. If it's a failure, the route I've gone, it's not a waste. I've learned, and the few dollars I've invested so far, can mostly be repurposed in a "REAL" Jig.

[Brice Rogers]

Mark, thanks for the explanation of your background. I didn't know your familiarity with thread specs. If I came off as condescending, it wasn't my intention. I myself, while not an expert, have learned a lot about thread specs in the past 5 or 10 years as I do single-point threading on steel shafts using my metal lathe.

Yes, I would agree that you came up with a design that works and you overcame a number of issue. On some of my projects I consider that the "journey" is at least as important as the end destination.

[Mark Greenbaum]

Hey Brice, sorry if I came off as harsh. I really enjoy the camaraderie of this forum, and I do learn a lot from all of the participants. Back when I was kid (Paleolithic Epoch), one of my first drafting competitions was drawing a Locomotive Screw Jack. It looked like a trumpet with a huge screw coming through it. Classic drafting book exercise. I was captivated by the form of Acme Screw Threads. I won an Honorable Mention in the Detroit Industrial Arts Competition of 1966. But not for that one, but a simple truncated cone development drawing. Thanks for watching this show, and I hope we all learn how to do cool stuff, better.

[Dane Riley]

There can't be any play anywhere. I suspect you will need to lock the dovetail with locking screws tapped in the sides.DSC_4285.jpg

The play on the threaded rod must also be eliminated. Mine has adjustable pressure on the rod and pressure on the nuts. Band-aids on top of band-aids. No play when you try to move the chuck. If the hollow form is thin you need to dampen the vibration with your hand. But it threads well, large or small.

[Mark Greenbaum]

Dane:

Thanks for that advice. I have already locked the dovetail slides with cams, and the lateral feed screw with a lock knob. I am going to add a tensioner to inhibit the leadscrew self-advance issue this weekend. Your rig looks really nice. What size screw is the leadscrew? It looks huge.

[Dane Riley]

Dane:

Thanks for that advice. I have already locked the dovetail slides with cams, and the lateral feed screw with a lock knob. I am going to add a tensioner to inhibit the leadscrew self-advance issue this weekend. Your rig looks really nice. What size screw is the leadscrew? It looks huge.

It is 1.25 x 8, so the chuck threads directly on. When Enco was around it was not expensive with a 20%o ff and free shipping. That may be why they got bought out.

The wood blocks with screws that push them into the leadscrew eliminate self feeding and play. Adjustable is good to be able be able to eliminate play while still being able to turn the leadscrew.

I know exactly what you a talking about when you mention your problems.

[Mark Greenbaum]

It is 1.25 x 8, so the chuck threads directly on. When Enco was around it was not expensive with a 20%o ff and free shipping. That may be why they got bought out.

The wood blocks with screws that push them into the leadscrew eliminate self feeding and play. Adjustable is good to be able be able to eliminate play while still being able to turn the leadscrew.

I know exactly what you a talking about when you mention your problems.

Dane: Take a few more pictures of the whole jig. I am sure I can glean some ideas from it. Thanks.

[Harold Wright]

Try Hartville Tool . They are on the internet and carry a lot of the adapters. Maybe you will get lucky.

[Mark Greenbaum]

Try Hartville Tool . They are on the internet and carry a lot of the adapters. Maybe you will get lucky.

I already have the adapter for my rig - custom machined from my old Nova G3/Shopsmith adapter. Thanks, though.

[Len Mullin]

Mark, you should check out Alan Stratton's video, he posted this week on his As Wood Turns woodturning site. He built his own threading devise, that will thread north american woods. Woods that aren't usually as hard as is needed for threading, you might pick up some ideas from his threader.
Len

[Mark Greenbaum]

Mark, you should check out Alan Stratton's video, he posted this week on his As Wood Turns woodturning site. He built his own threading devise, that will thread north american woods. Woods that aren't usually as hard as is needed for threading, you might pick up some ideas from his threader.
Len

Len: Thanks for that reference to Alan Stratton's video - I had already seen it, and Also we had Dennis Pauliss demonstrate at our club a few months ago, so I am familiar with all of the listed parts and techniques. I could not justify the cost or having yet another vise, so I basically have constructed one made of hardwoods. I did learn that I have to allow for at least a 1/2" of threads on the lids and vessels, because 10 threads per inch is pretty coarse. 5 threads should be really sufficient to accommodate most local hardwoods that I would choose to have threaded lids incorporated. The adapter that Alan suggested is not useable for my chuck. Oneway does offer on custom order an adapter from 3/4"-10 UNC to 1-1/4-8 TPI, but it was about $40. I lucked out having access to a great machinist. (Reminder to self - make him a threaded box and take in donuts). I hope this thread inspires others to try to use threads. It's an adventure and adds quite a bit of excitement to the craft and the final projects. Hopefully tonight I'll make another (better) object to showcase.

[Dean S Walker]

Check with one way lathe company

[Mark Greenbaum]

Dean: Read above. The JIG is completed, and the adapter has been made from Nova/Shopsmith adapter. Thanks.

[Dane Riley]

dane: Take a few more pictures of the whole jig. I am sure i can glean some ideas from it. Thanks.

ok

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