Mounting pots on a chassis front

[Avon]

Pots etc. can be a pain to mount through a hole in the chassis. The shaft is often too long and the anti-rotation tab can get in the way. Is there an M8 flanged / through hole "nut" perhaps, which could be glued to the front of the case, and allow the pot to be screwed back, until the shaft has the correct protrusion? Using Google doesn’t seem to find anything particularly suitable for use with pots.

 

[Vinny]

I am not entirely sure what you are having grief with......

However, to get everything "right", you mount the pot' to the panel, fit the knob, measure the distance between the back of the knob and fascia/plate, and then dismatle. Cut the spindle/shaft of the pot' down, by 1mm les than the measurement that you just took.

You do not have to use the anti-rotation tab - it is belt and braces.

Gluing a nut in place?????? I'd defo avoid that.

 

[cj66]

If it's a standard pot and/or you're sure it's a fit and forget i.e. the pot won't be repurposed later, then @Vinny has hit the nail on the head.
Otherwise make a simple L bracket to stand x mm behind the front panel, properly attached to the chassis floor, to mount the pot on. Leaving enough spindle to protrude beyond the front panel.

 

[Avon]

Since I’ve just spent £50 on a pot, I don’t want to cut anything off it. What I’d like is something that looks a bit like this, but where the “tube” is only a few mm long. The flat bit would go on the front of the facia, underneath the knob. The nut would secure the pot, behind the panel. I don’t want to have to “manufacture” anything, as I just want a simple solution.

 

[Mike1965]

Simple solution.

Extension Kit, Frame, Bush, Rod & Couplier | HIFICollective

Extension Kit, Frame, Bush, Rod & Couplier

www.hificollective.co.uk

 

[Vinny]

What I’d like is something that looks a bit like this, but where the “tube” is only a few mm long.

Do you posess a junior hacksaw and/or file. If so, you have your answer, unless you regard that as "manufacturing",

That said, personally, I would guess that where you end-up is not where you intended.

Unless I am missing something here, I can't see why cuting the spindle would be such a catastophe, it is very, very highly likely to be mounted to the same dimension plate. Allowance for thicker would be simple - the spindle would not bottom out in the hole in any knob.

 

[just an idea]

Is the threaded part too long? Solved with a couple of washers or possibly a nut on first to set how far it protrudes

 

[PaulMB]

Since I’ve just spent £50 on a pot, I don’t want to cut anything off it. What I’d like is something that looks a bit like this, but where the “tube” is only a few mm long. The flat bit would go on the front of the facia, underneath the knob. The nut would secure the pot, behind the panel. I don’t want to have to “manufacture” anything, as I just want a simple solution.

But then how would you fix the flange to the front or the back of the front panel? You could use 3 nuts-and-bolts but that would mean drilling 3 exactly placed holes in the front panel. Maybe I'm not understading, but it seems to me it would be easier to saw, or file if it is only 1 or 2mm, a few MM off the spindle. Do you have a vise to hold it in?

 

[Avon]

But then how would you fix the flange to the front or the back of the front panel? You could use 3 nuts-and-bolts but that would mean drilling 3 exactly placed holes in the front panel. Maybe I'm not understading, but it seems to me it would be easier to saw, or file if it is only 1 or 2mm, a few MM off the spindle. Do you have a vise to hold it in?

You could use double-sided tape or glue, but that isn't necessary if the tube doesn't go all the way through the panel, because the nut holding the pot to the back would keep it in place. Or just use washers to make the panel thicker, as suggested by @just an idea.

 

[Avon]

Thanks for the replies. I think I’ll buy an M8 flanged nut and glue it to the back of the front panel. The pot’s retaining nut will hold it from behind.

 

[sq225917]

That's what I'd do. Mount the pot rigidly, not on the panel, and use an extender shaft with bushing on panel.

 

[337alant]

Agree the extension kits give more flexibility on the mounting, it can also save you a considerable amount on hook up wire from back to front panel

821A PreAmp by Alan Towell, on Flickr

Alan

 

[PaulMB]

I suppose much would depend on the layout inside the amp. But making brackets, drilling holes in the "floor," putting together the extentions, all seems like a complicated solution to a simple problem.

 

[killie99]

The big advantage of the extension rods is that you minimise the wiring and can better keep signal wires away from any power sources/cables. Its actually a simple solution to a complicated problem and Alan’s example above shows it beautifully.

 

[PaulMB]

Perhaps you are right. But it depends on the layout, for instance if there is nothing in the way.

 

[Qwin]

The big advantage of the extension rods is that you minimise the wiring and can better keep signal wires away from any power sources/cables. Its actually a simple solution to a complicated problem and Alan’s example above shows it beautifully.

Good point.

 

[Avon]

This was what I wanted. A flanged plastic nut glued to the inside of the front panel.