Non-Stick Bushings Tight on Mandrel

[QuillandQuiver]

I've been having an issue lately with nonstick bushings being so tight on my mandrel that I can only get them off with pliers and some help from the lathe itself (essentially spinning them off). When I first used them, they slid on relatively well and I could remove them with my hands pretty easily. Now I really have to force them on (note: I didn't just go straight to the pliers. I wrestled them off there without damaging them several times). But now it's the only way to get them on and off.

Things I've done:
1) New bushings. Same problem
2) Used a 7mm barrel trimming bit to clear out the inside of the bushings. They're glue free inside.
3) Checked the mandrel for burs and CA glue. All smooth.. the bushings don't have trouble in one spot, they're impossibly tight the whole way.

Any insights?

 

[Gary Beasley]

They probably had some kind of oil on them when new. Have you tried a bit of wax on the mandrel?

 

[wouldentu2?]

Maybe CA inside the bushing you cannot see, soak them in acetone.
Maybe a burr on the mandrel or in the bushing, sand and wax both.

Try new bushings.

 

[montmill]

If misery loves company, I have the same problem and have tried wax, lightly sanding, then cleaning the mandrel to no avail.

 

[sorcerertd]

I've run into this also. I always leave one or two spacers on the mandrel so I can get a grip on the one further on the mandrel. If they are still tough, get a crescent wrench and size it over the spacer, then slide it off the mandrel shaft with that. Likewise you could find or make something similar. Just be careful not to scratch up the mandrel too much.

That being said, I'd recommend ditching the mandrel altogether. There's a lot of info about turning between centers around here for you to check out without me derailing your thread here about it. I still use the mandrel sometimes to hold barrels firmly when buffing on a wheel. That or for roughing things out in a hurry.

 

[QuillandQuiver]

All helpful stuff guys. I haven't tried wax yet but do you guys have recommendations on what kind of wax? (I don't have any on hand, or would you recommend anything that would be around the garage that might be a substitute before I can get some wax?)

Also, I would love to turn between centers but I only have a Penpal lathe that requires a new church and tailstock if I were to take that route.

 

[WriteON]

I need a crowbar to remove them. I might try an ultra thin coating of O Ring lubricant on the bushing hole applied with a Qtip. As light a coating as possible.

 

[TonyL]

All helpful stuff guys. I haven't tried wax yet but do you guys have recommendations on what kind of wax? (I don't have any on hand, or would you recommend anything that would be around the garage that might be a substitute before I can get some wax?)

Also, I would love to turn between centers but I only have a Penpal lathe that requires a new church and tailstock if I were to take that route.

You shouldn't have to do any this. Try a new set of bushings (least expensive route) or a new mandrel. Even if you ditch the mandrel for turning, you may want to apply your CA, other finishes, etc. to blanks while using a mandrel to simply maintain a concentric rotation.

I bought some 1/4" rod from HD (which I believe is larger in diam. than a pen mandrel .247) so that I can finish 3 to 4 blanks at a time.

With some CA bushings, I have to drill them out a bit, some I do not. I haven't found drilling them out to be easy.

Instead I bought some HDPE (or whatever the initials are) and made my own bushings with a hole think accommodates the larger diameter of the HD rod.

Good luck.

 

[egnald]

Hi All,

Like TonyL, I used to use purchased bushings, but eventually made my own using a piece of HDPE Rod. I drilled mine out with a 1/4-inch standard drill. They do fit tight on one of my mandrels, one made using "D" drill rod (0.246 inches diameter) but fit only nice and snug on my mandrel made using "C" drill rod (0.242 inches). My go-to is the "D" mandrel unless I am turning something with tight fitting 7mm tubes, then I change it out to the "C" mandrel.

I suppose you could measure the diameter of your mandrel and re-drill the bushings with an appropriately sized drill. "C" is 0.242 inches, "D" is 0.246 inches, 1/4 or "E" is 0.250, "F" is 0.257, "G" 0.261.

I clean my bushings after every use by dropping them in a small glass jar of acetone. Any leftover CA dissolves after a few minutes and they are back in like new condition.

Regards,
Dave

PS I bought both my "C" and "D" drill rod and my HDPE from Grainger. The drill rods were about $6-$7 each (3 feet long) and the HDPE was about $15 (3/4 inch diameter and 4 feet long). My drill bits however, I buy from McMaster-Carr, especially the drill bits designed especially for drilling plastic. They cost about $15 - $20 depending on the size.

 

[QuillandQuiver]

Here's where I'm at: After scouring my house for any sort of lubricant, I had almost resorted to using some motor oil just because I'm impatient. I tried a bit of wax that was more tacky that slippery so that was a no-go.

The 7mm barrel trimmer bit is obviously not a true 7 millimeters and only worked for taking out any excess glue but I took the regular 7mm drill bit and took off a bit of the bushing so that they were a hairsbreadth bigger than the mandrel. They slide on like a charm and don't wobble like you might expect (the pressure from the tailstock and mandrel saver keeps them "suspended" on center if that makes any sense).

 

[egnald]

The 7mm barrel trimmer bit is obviously not a true 7 millimeters and only worked for taking out any excess glue but I took the regular 7mm drill bit and took off a bit of the bushing so that they were a hairsbreadth bigger than the mandrel. They slide on like a charm and don't wobble like you might expect (the pressure from the tailstock and mandrel saver keeps them "suspended" on center if that makes any sense).

That is Good News! - I am glad you found a solution that works for you. You are correct, the 7mm barrel trimmer/reamer is sized for the inside diameter of a 7mm tube (which is more on the order of 6.15mm (0.24 inches) whereas the drill is 7mm (0.276 inches) - the next size up from the "G" drill indicated in my previous post. - Dave