Robust banjo locking handle for tool rest problems.....(photo)

[odie]

After using my Robust banjo for several years, I'm finding that the screw threads for the clamp blocks have stripped. The problem is this screw is not hardened like a normal bolt would be. The cause is my cranking on the handle too hard, and over time, the threads at the tip have bent over, and eventually failed. I have replaced this locking handle with a new one from McMaster Carr. The description and part# is as follows:

Zinc Adjustable-Position Handle
with 3/8"-16 Threaded 2-3/8" Long Stud, 2-5/8" Projection, Black
6271K71

If you haven't checked the threads on your locking handle, you should.....only takes a second to slide it out and look.

Photo shows my damaged threads on bottom, and the new replacement part.

-----odie-----

 

[robo hippy]

I used a small pair of vice grips. The threads on the jaws of the vice grips match the thread on the hardened set screw almost identically. I have long held that the lever part should be like the T handles on bench vices, and the top of the T slides up and down. I have a 16 inch Robust Liberty, which they no longer make, and the lever on the tool rest lock gets in the way of the tool rest when moving things around. Had a friend make one of the sliding T handles for my old PM 3520A, and it worked beautifully.

robo hippy

 

[Tom Gall]

Odie, I don't really know what the Robust banjo looks like, but that bolt looks excessively long. I would have sawed the stripped threads off, chamfer the end and reused the old one ... maybe!

 

[Don Wattenhofer]

I would bet that Robust would have replaced that lever if they knew there was a problem.

 

[hockenbery]

Odie, I don't really know what the Robust banjo looks like, but that bolt looks excessively long. I would have sawed the stripped threads off, chamfer the end and reused the old one ... maybe!

It’s a pair of pinch nuts that close on the toolrest post. so The bolt goes the full width of the banjo hole for the nuts.
powermatic had this on the first 3520s. They came back to this design on the jet 1640, jet 1840 and then the 3520c.

it’s a very positive lock. Need to get used to using it -
I am used to letting go of the handle when I take a rest out And lifting thehandle to put in the next rest.
when I let go of the handle on a pinch nut banjo the 1/4 turn of the falling handle closes the nuts blocking the opening and I have to take two open turns on the lock handle and push the nut out of the opening- all the time remembering Don Geiger’s instruction to open the lock an extra turn.

 

[odie]

Odie, I don't really know what the Robust banjo looks like, but that bolt looks excessively long. I would have sawed the stripped threads off, chamfer the end and reused the old one ... maybe!

As Al said in the post above this one, the threaded post goes all the way through the width of the banjo, and it needs to be this long. In the photo, the defective handle on the bottom is actually trimmed about 1/4", so that it's flush to the other side. This was because it occasionally rubbed against my turning when I wanted the banjo as close as possible. By trimming it, I can get the banjo that much closer to where I need it.

it’s a very positive lock. Need to get used to using it -

Yep, you're right, Al.

It definitely doesn't need to be tightened as much as I had been doing it. Lesson learned!

-----odie-----

 

[Tom Gall]

As Al said in the post above this one, the threaded post goes all the way through the width of the banjo, and it needs to be this long. In the photo, the defective handle on the bottom is actually trimmed about 1/4", so that it's flush to the other side. This was because it occasionally rubbed against my turning when I wanted the banjo as close as possible. By trimming it, I can get the banjo that much closer to where I need it.
-----odie-----

Aha! I have the same type of handle with a 1/2" (13 tpi ?) bolt that tightens directly on the tool rest post. I guess that is why mine is much shorter.

 

[DON FRANK]

Odie, all of the above and if you have a collar to set the height for most of your cutting it takes very little pressure to hold the rest in place.

 

[odie]

Odie, all of the above and if you have a collar to set the height for most of your cutting it takes very little pressure to hold the rest in place.

Hi Don.....

If the threads were hardened like most bolt threads are, you could tighten the clamp as you'd expect you could. Yes, I found out the hard way that you damage the threads by tightening as much as you would normally tighten a nut on a bolt. As you and others have said, it doesn't take that much pressure to securely grip the tool rest.....well, now I know, and this lesson has been learned!

Instead of collars, I'm using quick release hose clamps. I've chosen these clamps to secure the height settings on my tool rests because I am continually changing the height of the rest according to the width of the tool I'm currently using.

-----odie-----

 

[Mark Jundanian]

Instead of collars, I'm using quick release hose clamps. I've chosen these clamps to secure the height settings on my tool rests because I am continually changing the height of the rest according to the width of the tool I'm currently using.

Odie, I use small spring clamps to control the height of my tool rests. Quick and easy tiny adjustments, without tools. These used to cost about a dollar in the before times. You do have to position the handles out of the way, but that's not complicated. The clamps can stay on the tool rests when not in use.

 

[odie]

Odie, I use small spring clamps to control the height of my tool rests. Quick and easy tiny adjustments, without tools. These used to cost about a dollar in the before times. You do have to position the handles out of the way, but that's not complicated. The clamps can stay on the tool rests when not in use.

Hi Mark.....this is what I'm using:

They are quick to adjust and easy to use, as well as for tiny adjustments. It would be difficult for me to change my mind about this current clamp I'm using, but I'm open to anything new and improved.

Can you post a link to the clamp you're using?

BTW, these are available from CSUSA at the following link:

Turners Select Center-Set Post Lock - 2 Pack

A must have for every woodturner who does texturing or uses other woodturning tools that require cutting on center, the Turners Select™ Center-Set Post Lock device lets you lock your tool rest post at the desired position while allowing you to rotate it side to side as needed. Simply slide lock...

www.woodturnerscatalog.com

-----odie-----

 

[Mark Jundanian]

I like that your hose clamps are tool-less. The spring clamps are nothing special, just off the shelf hardware store item. I usually keep one on each tool rest.

 

[odie]

I like that your hose clamps are tool-less. The spring clamps are nothing special, just off the shelf hardware store item. I usually keep one on each tool rest.

View attachment 50013
View attachment 50014

OK Mark....quick and easy is the way to go, and both of our clamp styles are that!

Not only are the hose clamps I use tool-less, but the little yellow handle pops off of there.....just in case a more compact application is needed.

I also have notches to show the tool rest height cut into the tool post with a hacksaw. This allows me to adjust the tool rest height accurately with the width of the tool shank in mind.

-----odie-----

 

[Breck Whitworth]

After using my Robust banjo for several years, I'm finding that the screw threads for the clamp blocks have stripped. The problem is this screw is not hardened like a normal bolt would be. The cause is my cranking on the handle too hard, and over time, the threads at the tip have bent over, and eventually failed. I have replaced this locking handle with a new one from McMaster Carr. The description and part# is as follows:

Zinc Adjustable-Position Handle
with 3/8"-16 Threaded 2-3/8" Long Stud, 2-5/8" Projection, Black
6271K71

If you haven't checked the threads on your locking handle, you should.....only takes a second to slide it out and look.

Photo shows my damaged threads on bottom, and the new replacement part.

-----odie-----

View attachment 49685

Odie thanks for posting about this I will check the one on my American Beauty.

 

[David Propst]

I like the tabs on these hose clamps. The plastic ones tend to fall off in my experience.

https://a.co/d/6Tl2EZD

 

[odie]

I like the tabs on these hose clamps. The plastic ones tend to fall off in my experience.

https://a.co/d/6Tl2EZD

Yes David......these are better. I have a few of them, too.

Thanks for the link. I think I'll buy a few more of those.

-----odie-----

 

[Dennis Weiner]

I use conduit connectors to adjust tool rest height as published in AAW Tips and Techniques Volume 28:6:19. Cost is about a dollar each for the 1" male and female threaded connectors. See pictures and description on the mid-left of the page:

 

[William Rogers]

@odie I believe you are over tightening your banjo. Many times in manufacturing we designed an easily replaceable piece to fail before damage can be done to a more expensive part. You now have these hardened threads on the bolt, but the mating part (more expensive and difficult to get) is likely not as hard and could now be more prone to failure. Just saying.

This is the same design Powermatic used on the Model 90. I had this lathe and now a Robust (Brent has acknowledge the design was taken from the PM 90) and have not had this problem. About 8 years of use combined.

 

[odie]

@odie I believe you are over tightening your banjo. Many times in manufacturing we designed an easily replaceable piece to fail before damage can be done to a more expensive part. You now have these hardened threads on the bolt, but the mating part (more expensive and difficult to get) is likely not as hard and could now be more prone to failure. Just saying.

This is the same design Powermatic used on the Model 90. I had this lathe and now a Robust (Brent has acknowledge the design was taken from the PM 90) and have not had this problem. About 8 years of use combined.

Yes, Bill......I agree that I was tightening too much. If the bolt had been hardened, this would not have been a problem at all. I have amended my ways, and am not tightening as much now. I have also shortened the lever, so that I can't get as much leverage, and inadvertently tighten too much in the future.

-----odie-----

 

[William Rogers]

Yes, Bill......I agree that I was tightening too much. If the bolt had been hardened, this would not have been a problem at all. I have amended my ways, and am not tightening as much now. I have also shortened the lever, so that I can't get as much leverage, and inadvertently tighten too much in the future.

-----odie-----

Not the point I was trying to make. A hardened bolt may strip the mating part. You “may” have been worse off replacing the other part.

 

[odie]

Not the point I was trying to make. A hardened bolt may strip the mating part. You “may” have been worse off replacing the other part.

OK, I get it now, Bill.....I'll keep that in mind.

-----odie-----

 

[robo hippy]

I don't think the wedged system needs as much pressure to keep the tool rest post tight. If you have just the set screw type, they seem to need a lot more pressure. Hate it when I am turning boxes on my mini lathe and the banjo slips..... As far as I am concerned, the handle needs to be made out of the same metal as the set screw, that way it won't wear out, ever. The sliding T rest I had made, 20 plus years ago is still functioning fine.

robo hippy

 

[hughie]

After using my Robust banjo for several years, I'm finding that the screw threads for the clamp blocks have stripped. The problem is this screw is not hardened like a normal bolt would be. The cause is my cranking on the handle too hard, and over time, the threads at the tip have bent over, and eventually failed. I have replaced this locking handle with a new one from McMaster Carr. The description and part# is as follows:

Zinc Adjustable-Position Handle
with 3/8"-16 Threaded 2-3/8" Long Stud, 2-5/8" Projection, Black
6271K71

If you haven't checked the threads on your locking handle, you should.....only takes a second to slide it out and look.

Photo shows my damaged threads on bottom, and the new replacement part.

-----odie-----

View attachment 49685

If you have enough wall thickness move up to the next dia. I use these for most locking type situations. I generally get them too long so I can shorten them as they wear out