I want to put a different volume knob on my shaft but it's not long enough..
It's a metal shaft, what's the best method of making it longer so I can accommodate my new knob.?
Cheers...
It's a metal shaft, what's the best method of making it longer so I can accommodate my new knob.?
Cheers...
There are metal couplers available for round or flatted metal shafts. Some are simple tubes, some allow misalignment.
Examples:
https://www.amazon.com/jyibinee-Stainless-Connector-Numerical-Accessories/dp/B0CWRSC3HP/ref=sr_1_2
https://www.aliexpress.us/item/3256804902771326.html?src=google&gatewayAdapt=glo2usa
Examples:
https://www.amazon.com/jyibinee-Stainless-Connector-Numerical-Accessories/dp/B0CWRSC3HP/ref=sr_1_2
https://www.aliexpress.us/item/3256804902771326.html?src=google&gatewayAdapt=glo2usa
Hi,
In this store you can buy everything you need. I think so.
https://www.modushop.pl/akcesoria-do-potencjometrow.html
In this store you can buy everything you need. I think so.
https://www.modushop.pl/akcesoria-do-potencjometrow.html
Not a lot, and that's where the problem arises.By how much do you need to extend the shaft?
An extra 5-6mm should do it, any "sleeve" I put over the existing shaft is likely to be in the way..
It is why I asked, as couplers won't suit a short extension. Also, should supply a bit more detail so we may help devise an effective strategy. Things like size type of shaft. Original uncut D or already cut short?Not a lot, and that's where the problem arises.
An extra 5-6mm should do it, any "sleeve" I put over the existing shaft is likely to be in the way..
I would slit the end of the shaft using a dremel cutoff wheel. Then shape and fit a flat and hard bit of steel into the slit with length required for extension. Then cover the flat hanging out of the slit with an epoxy putty. You can hand sand that back into the shaft shape after cure
You could just cut a piece of shaft from a spare pot and epoxy it on, with e.g. a lap joint for more strength. If you don't have a spare pot, you could also fashion the extension from a wood dowel / rod.
I'm pretty sure any kind of glue by itself will not make a permanent repair.
Assuming it's a round (smooth) shaft, I would look at cutting two flats on either side of the pot shaft, leaving a tab in the middle that's about 1/4 to 1/3 the width of the shaft, perhaps 1/4" long (3–4 mm). Then find a piece of aluminum rod the same diameter as the shaft, and cut a groove the same width and depth to fit the modified shaft, so they form a good mating pair. Tape those securely together and drill a small (1/16"/ 2–3 mm) hole through both parts, the diameter of which should match some aluminum/copper/brass wire or rod you have. Cut the pin to be just slightly longer than the shaft diameter, then push the pin through and gently pound the ends down so they widen a little and lock the pin in place. File the pin ends down to the rod surface. Test-fit beforehand, and if it's a bit wobbly, a little epoxy would stabilize it. File a new flat on the extension if needed.
Aluminum rod can be found at hobby or hardware stores, or of course online. An X-acto micro saw and a file should do the job. Thin-walled brass tubing is available from the same sources, and could be slid over the repair if your fit-up is less than perfect. If the pot has a splined shaft, that's impossible to create from scratch, so you might see of there is another matching spline on a pot in your junk drawer that could be cut off and used for an extension.
I know this sounds like a lot of fussy work, but this will create a really permanent repair you'll never have to think about again. Or, you can just buy a new pot with the right shaft length.
Assuming it's a round (smooth) shaft, I would look at cutting two flats on either side of the pot shaft, leaving a tab in the middle that's about 1/4 to 1/3 the width of the shaft, perhaps 1/4" long (3–4 mm). Then find a piece of aluminum rod the same diameter as the shaft, and cut a groove the same width and depth to fit the modified shaft, so they form a good mating pair. Tape those securely together and drill a small (1/16"/ 2–3 mm) hole through both parts, the diameter of which should match some aluminum/copper/brass wire or rod you have. Cut the pin to be just slightly longer than the shaft diameter, then push the pin through and gently pound the ends down so they widen a little and lock the pin in place. File the pin ends down to the rod surface. Test-fit beforehand, and if it's a bit wobbly, a little epoxy would stabilize it. File a new flat on the extension if needed.
Aluminum rod can be found at hobby or hardware stores, or of course online. An X-acto micro saw and a file should do the job. Thin-walled brass tubing is available from the same sources, and could be slid over the repair if your fit-up is less than perfect. If the pot has a splined shaft, that's impossible to create from scratch, so you might see of there is another matching spline on a pot in your junk drawer that could be cut off and used for an extension.
I know this sounds like a lot of fussy work, but this will create a really permanent repair you'll never have to think about again. Or, you can just buy a new pot with the right shaft length.
A few useful links for the topic:
https://antiqueradios.com/forums/viewtopic.php?t=422514
https://www.homedepot.com/p/Automat...ition-25-Pack-ASIMY16HW-1-2-14-6-2P/306172701
https://antiqueradios.com/forums/viewtopic.php?t=422514
https://www.homedepot.com/p/Automat...ition-25-Pack-ASIMY16HW-1-2-14-6-2P/306172701
Thanks for all the ideas everyone.
I think I know what I need to do now!
Not touching it until after tomorrow though..
Happy New Years wherever you are!
Rik
I think I know what I need to do now!
Not touching it until after tomorrow though..
Happy New Years wherever you are!
Rik
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