Threaded speaker poles

[bruce]

I have a pair of speakers (RCF Evox) which have a 2 piece speaker pole. The "main pole" has a screwed (M20) thread on the bottom, to screw into the sub, the usual telescopic section with a clamp and pin, and a 35mm top section that the HF unit sits on.

Sometimes that's enough - especially if the sub is on a raised stage - but there's also a 50cm "extension pole" with a M20 threaded screw/socket either end.  

I used the extension poles for the first time in ages last week. Screwed them into the subs, screwed the main pole into the extension - "hand-tight" - and proceeded with the gig.

Packing up time, couldn't separate the poles, no matter how hard we twisted by hand. They unscrewed fine from the sub, but couldn't separate the 2 sections by hand. Just put the whole pole back in the car and headed home.

Interestingly, this happened with BOTH poles - no matter how hard we tried, we couldn't separate them. Maybe it was a temperature thing - they'd been in the car overnight before use, then brought into a warm space.

Next day, tried to separate them again. They were pretty solid - first try with normal "toolbox tools" wouldn't shift them, it took a vice and stilsons to get them apart.

I guess I should grease the threads, or some silicon lube, or something..... any suggestions? Should there be a felt washer or something at the join?

 

 

[sunray]

1 hour ago, bruce said:

I have a pair of speakers (RCF Evox) which have a 2 piece speaker pole. The "main pole" has a screwed (M20) thread on the bottom, to screw into the sub, the usual telescopic section with a clamp and pin, and a 35mm top section that the HF unit sits on.

Sometimes that's enough - especially if the sub is on a raised stage - but there's also a 50cm "extension pole" with a M20 threaded screw/socket either end.  

I used the extension poles for the first time in ages last week. Screwed them into the subs, screwed the main pole into the extension - "hand-tight" - and proceeded with the gig.

Packing up time, couldn't separate the poles, no matter how hard we twisted by hand. They unscrewed fine from the sub, but couldn't separate the 2 sections by hand. Just put the whole pole back in the car and headed home.

Interestingly, this happened with BOTH poles - no matter how hard we tried, we couldn't separate them. Maybe it was a temperature thing - they'd been in the car overnight before use, then brought into a warm space.

Next day, tried to separate them again. They were pretty solid - first try with normal "toolbox tools" wouldn't shift them, it took a vice and stilsons to get them apart.

I guess I should grease the threads, or some silicon lube, or something..... any suggestions? Should there be a felt washer or something at the join?

 

 

Usually when it's a temperature issue it's due to getting cold when mated but there's no real reason it can't be the other way, especially if the 2 parts are different metals

Obviously you don't want them to be mucky to handle which will also collect dirt. Something which drys would be better, something like furniture polish herhaps?

[Robin D]

Silicon spray is your friend. Not standard WD40 although you can get WD40 branded silicon spray. 

[pmiller056]

Put a washer between the sections before you assemble them together. The hard part is not losing the washers between jobs....

[Stuart91]

I had some Dynacord speaker poles that had the M20 thread on them. They had holes drilled through the pole towards the bottom, which would allow a cross-head screwdriver or similar to be inserted through to apply leverage.

Despite having them for many years, we never needed to resort to that...