Help removing small parts from a threaded mandrel

[SmokeWalker]

Hey everyone,

I've got some 5/16 diameter plastic parts (which cannot be marred) to remove from a 5-40 threaded mandrel, and after they've been machined, they're kind of hard to remove. Do you have any suggestions? I've been using a set of spark plug pliers, but they only grip the part 80-90% of the time, otherwise, the parts slip and you need to get a piece of rubber or something to help the pliers get enough grip.

SW.

 

[Shootymacshootface]

Try hot water.

 

[Flyinfool]

Grab the parts in a collet to unscrew the mandrel? Then the collet should open enough to easily remove the part from there.

 

[SmokeWalker]

Grab the parts in a collet to unscrew the mandrel? Then the collet should open enough to easily remove the part from there.

See, that's what I thought, but the only collet block I have is so big that you can't really get it close enough to the part to grip it without cutting yourself on the cutting tool(s)!

 

[tmenyc]

rounded vise-grip, coated or wrapped in duct tape to be non-marring? Spark plug wrenches, a tool I use all the time in my fountain pen repair work, won't give you enough of a grip. I use them because I know that if that wrench, or a pair of them, won't do the job I usually need to heat or soak or ultrasound the parts to help loosen them and that more force would ruin them. In your case it's the opposite: you need a bit more grip. I've found duct tape has grip of its own and sticks well to a vise grip's form.
Tim

 

[Flyinfool]

See, that's what I thought, but the only collet block I have is so big that you can't really get it close enough to the part to grip it without cutting yourself on the cutting tool(s)!

Sounds like a perfect excuse to get some new tools.......

 

[RJSakowski]

I am assuming that your part is jamming up against a shoulder when turning. I f you make a threaded bushing for a stop and use a jam nut behind it, you can loosen the jam nut and back off the bushing. The part should easily unscrew then.

 

[SmokeWalker]

I am assuming that your part is jamming up against a shoulder when turning. I f you make a threaded bushing for a stop and use a jam nut behind it, you can loosen the jam nut and back off the bushing. The part should easily unscrew then.

No, not quite. That would make it way too time consuming to load to the correct depth for the machining operations. This is really small.

 

[SubtleHustle]

A strap wrench? Or is it too small for that?

 

[SmokeWalker]

A strap wrench? Or is it too small for that?

OD is 5/16.