Does anyone know where I can get a large knob which measures about 2” or 2-1/4” in diameter for a DIY preamp project? I have been all over the net but can’t seem to find anything larger 1.5”. Thank you in advance
luvrockin:
48mm diameter knobs are readily available on eBay and AliExpress. Going larger than that is tough (I know, I've tried). I commissioned Viljo Mirrandi (https://www.viljomarrandi.com), whom I found after an extensive search, to make a custom 56mm stainless steel knob for me. That was about 8 years ago, and his knob was exceptional (no pun intended), but I don't know if he's still doing that sort of work.
Good luck with your search. If you find good options, please post a note about them.
Regards,
Scott
48mm diameter knobs are readily available on eBay and AliExpress. Going larger than that is tough (I know, I've tried). I commissioned Viljo Mirrandi (https://www.viljomarrandi.com), whom I found after an extensive search, to make a custom 56mm stainless steel knob for me. That was about 8 years ago, and his knob was exceptional (no pun intended), but I don't know if he's still doing that sort of work.
Good luck with your search. If you find good options, please post a note about them.
Regards,
Scott
Check with some local ham radio guys, tuning knobs are usually pretty large.
Old ones will be bakelite, and solid metal will be hard to find.
Regardless, remember you have to specify what kind of shaft it is for.
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Search for 'Large instrument knobs'...
Used in industrial drives also, and specify shaft diameter.
Casual search found 42 mm knobs at 30 cents from India, MOQ 100 pieces.
And if it a pre amp, use a super quality pot, and think about multi turn if needed.
Some old drives here had a pot with an indicator which looks like the old cassette counters to show turns.
Used in industrial drives also, and specify shaft diameter.
Casual search found 42 mm knobs at 30 cents from India, MOQ 100 pieces.
And if it a pre amp, use a super quality pot, and think about multi turn if needed.
Some old drives here had a pot with an indicator which looks like the old cassette counters to show turns.
Hamfest swap meets may have collections of old knobs, and other interesting parts and test instruments.
Glen at A1 Parts has some that large: https://www.a1parts.ca/knobs/index.htm
find "GW4130" in the page to find the largest ones.
find "GW4130" in the page to find the largest ones.
Not bad, with up to 3" knob diameter, but they have an odd shaft size.
Maybe you could make an adapter sleeve from metal tubing, with a hole for clearance for the set screw.
Maybe you could make an adapter sleeve from metal tubing, with a hole for clearance for the set screw.
Or not as elegant, but it works, wrap tape around the shaft to build an adapter.
Also you could fill the hole with hot glue and stick it on the shaft. If you coat the shaft with WD40 first, you can slide the knob off when the glue hardens if I remember correctly.
Also you could fill the hole with hot glue and stick it on the shaft. If you coat the shaft with WD40 first, you can slide the knob off when the glue hardens if I remember correctly.
GD-Parts also has a bunch of knobs including this one that's 48x22 with a 6mm shaft.
https://www.goodcomponent.com/produ...ouble-set-screws4822mmblackgdak0172-1297.html
https://www.goodcomponent.com/produ...ouble-set-screws4822mmblackgdak0172-1297.html
Tape does work ok if it's tight enough on the knob, or if there's enough friction. Hot glue is a good idea,
but centering the knob around the shaft would be difficult to get right, so it won't be eccentric when turned.
Something like Mortite instead of hot glue might work as well.
In that case, you can actually cast your own, using epoxy putty and silicon mold release spray.
Use a jar lid as the pattern. Many choices, out to 100 mm.
Another alternate is built up fiber reinforced epoxy, careful when working around glass dust.
Some grades can even be painted.
Go on, be creative, have fun.
Use a jar lid as the pattern. Many choices, out to 100 mm.
Another alternate is built up fiber reinforced epoxy, careful when working around glass dust.
Some grades can even be painted.
Go on, be creative, have fun.
Knobs are not that hard to 3D print, with whatever shaft type (D flat, round) and size and depth you require.
If you need a weighted knob, just design in the opening for the weighting material of choice.
I suppose they could be sanded and painted for best aesthetics, but I've not tried that - I'm not that particular.
Both of these are 50m diameter, printed at 0.2 mm layer height ( I think ).
If you need a weighted knob, just design in the opening for the weighting material of choice.
I suppose they could be sanded and painted for best aesthetics, but I've not tried that - I'm not that particular.
Both of these are 50m diameter, printed at 0.2 mm layer height ( I think ).
Attachments
Nice job with the 3D printer.
I made these in high school metal shop some 50 years ago on the lathe from solid brass.
Only 28 mm but that's the largest stock I could get at the time.
Attachments
ModuShop has a couple: https://modushop.biz/site/index.php?route=product/search&search=knob&description=true
They're nicely made.
Tom
They're nicely made.
Tom