M42 Adapter stuck on DSI imager

[Prickly]

Hi,

Wondering about any thoughts on removing a stuck M42 adapter belonging to a nautilus filter wheel from a DSI 3 ccd camera.

Im presuming I need to unscrew it anticlockwise but it just wont budge.

Appreciate any suggestions

Cheers
David

[Shiraz (Ray)]

Hi David

No experience with DSI3, but had an adapter bind to an Atik filter wheel. Used a jar lid unscrewer belonging to wife - she got it a kitchen supplies places. This has jaws that self adjust to almost any diameter lid and a handle to get a bit of leverage - worked a treat with a bit of selotape to protect the adapter. She might get the gadget back one day.

Could be worth trying if you can find one. Good luck

[JD2439975 (Justin)]

Could try sticking it in the fridge, cooling might help free it up?
But get a second opinion on that first...

[Barrykgerdes]

Sticky fine threads on aluminium can be quite a problem. It is often caused by fine (hard) dirt on the thread. When you try to undo it it digs into the aluminium and forms a locking device. Sometimes the already mentioned fixes work but severe cases will destroy the thread on either or both items if force is used.

I find the only way is to cut the least expensive item off and cut my losses.

Barry

[gbeal]

Can you grip both pieces? I am having trouble envisaging what they look like.
Filters are threaded items that stick are sometimes able to be undone by pushing one against a piece of rubber, a mat or similar. In my case I have a cut piece of bike inner tube. Try it, it might avert the Gerdes Method, LOL.
Gary

[Omaroo (Chris Malikoff)]

For situations like this, I usually get out the trusty Dremel Mototool fitted with a fine cutting disc and cut two opposed shallow slots in the offending item's rim. Then it's easy to remove with a steel ruler and doesn't affect the items future use. Use the ruler as a flat screwdriver in the slots you've cut, and this provides a clean turning force that doesn't warp the threads. In addition to the dirt problem, some of these aluminium items are made too soft, and they warp a little - especially when you try and grip them hard squeezing by hand.

[JohnH]

WD40 (so long as you can get clear of optics) and/or judicious application of heat have worked for me in the past.

PTFE tape on the threads prior to re-assembly will prevent recurrance.

[Prickly]

Thanks everyone.

Live and learn and will try PTFE tape in future. I will try some of the ideas below and if all else fails might take it to a machining shop to see what they can do (slot approach sounds a clever idea).

Tried heat but already but unfortunately a no go. Might take a trip to Robyns kitchen as the can opener might be useful anyway.

Cheers
David

[Prickly]

Just a followup regarding progress:

Located the adjustable jar opener at big W. Worked a treat!

Thread seal tape next time round.

Thanks for your help all and for the great idea Ray.

David