What are these?
 

Just in case they maybe useful, does anyone know what these are?

Re: What are these
 

Coil formers?

Andy

Re: What are these
 

Posible there are gaps for the windings to go from oe section to another

Re: What are these?
 

Some sort of RF choke??

Re: What are these?
 

Are the made from aluminium? If so they look like some push on transistor heatsinks I've seen.

Re: What are these?
 

Those slots would have been expensive to cut in an aluminium heatsink, and not necessary. Bushes for threads wouldn't have been needed either.

If a hard plastic or bakelite, then I think they're coil formers'

Any clues in where they came from?

David

Re: What are these?
 

To me those slots on the base look like they are for some form of locking mechanism. I am fairly certain I have seen a similar method of locking before but my memory fails me.

Re: What are these?
 

Can you read the text in the recess?

Re: What are these?
 

I suggest formers for wirewound resistors. I had a Pye potentiometer unit with a number of similar coils for high stability close tolerance resistors for the decade multipliers. I am assuming the material is ebonite.
A much larger version of the sort of bobbin we see inside an Avo 7 or 8, or the Universal Avominor.
wme_bill

Re: What are these?
 

I was going to say a coil former for a spark transformer off a gas appliance but then again they're normally quite cheap plasticky things, this looks rather more robust

Re: What are these?
 

TO5 sized transistor heatsinks.

Joe

Re: What are these?
 

"TO5 sized transistor heatsinks." was going to suggest that too as Martin did but "Those slots would have been expensive to cut in an aluminium heatsink, and not necessary." as David says, same goes for the threaded inserts and look at the size, way too big for TO5.

Also being made out of ali & not a ferrite type material EG a conductor without a insulated covering rules out coil formers surely.

Andy.

Re: What are these?
 

Possible that it’s a shaft coupling in a drive system. This acts as a damper for slight miss alignment of the two shafts. Motor to reduction gear box – pump etc.

Bob

Re: What are these?
 

It does look a bit like one of those. I have one somewhere because one day it will 'come 'in'. But its a flexible plastic and has much thinner rings, joined in different places. Similar to this one: https://uk.rs-online.com/web/p/couplings/4106512/

Re: What are these?
 

Thanks, lot's of suggestions. They are plastic. The text reads A.P. 5461 J.D. the chap who they came from worked on medical equipment in a hospital. They are rigid. Plug is for size guide.