ways to attach eyelet board to chassis?

[kbobb]

Hi folks,

Doing my first kit and was wondering how to attach an eyelet board to chassis (with pros & cons of that method) other than metal screw/nuts/bolts?

This is for a 5e3 and I was wondering about plastic/rubber self adhesive or glue on spacers. They seem like they'd be easy to work with and non-conductive - but would they adhere long term with all the vibrations of the amp.

Any experiences or thoughts would be appreciated.

Also, when wiring the board some wires run on the backside of the board - what is the reason for this and could they run on top of the board over the other components?

Thanks a lot for your help.

[PRNDL]

Also, when wiring the board some wires run on the backside of the board

B+ power supply rails are often run under the board to make the layout neat.

Some signal wires are run under the board to reduce coupling to other wires that run higher voltages.

I've found that simple changes to a layout can result in huge problems with noise and feedback. This is, however, only true for a few highly sensitive issues.

Doing my first kit and was wondering how to attach an eyelet board to chassis (

Metal spacer nuts are the tried and true method and is preferred because it locks the board solidly in place. Any small movement will break solder joints over time.

Those plastic spacers will break down over time (the span of decades).

OTOH, Ace Hardware does have some nifty nylon spacers, screws and nuts that might be worthwhile to look at.

[scole]

i use the nylon spacers, about 3/4 long, use no. 10 screws with nylon insert lock nuts.

[Enzo]

It shouldn't matter that your mounting hardware is conductive, the mounting holes are not full of wires and components any more than the mounting holes on a tube socket are. A nut and bolt is simple, reliable, proven to work,

My personal approach? Run the screw through from the outside and spin a nut down tight on it. Use a star washer or a nut with a captive one. Now you have sturdy threaded screws sticking into the chassis cavity. Drop the plain board over the screws, then the eyelet board, and put a second nut on each screw and tighten. Now the boards are clamped between nuts. It won't go any where. 10,000,000 Fenders can't be wrong.

GLue is not a good idea. What happens when you want to pull the board up for some reason?

You will find that running some wires under the board neatens up your build quite a bit. Having a bunch of wires running here and there getting in the way is a pain in the ass. Certainly wires carying DC won't cause signal problems back there.

[kbobb]

Thanks all

Thanks folks for the advice.
I sure don't plan on re-inventing the wheel just wonder about why things are the way they are.
Scole, when you use the spacers where do you put them? - between the boards, between boards and chassis?
Enzo and PRNDL - if you don't use spacers between the loaded board and blank board does it crush the wires on the back of the loaded board?
Do you ever put a spacer between the 2 boards to give the wires some space?


Thanks again for the great help!

[lmolter]

Run the screw through from the outside and spin a nut down tight on it. Use a star washer or a nut with a captive one. Now you have sturdy threaded screws sticking into the chassis cavity. Drop the plain board over the screws, then the eyelet board, and put a second nut on each screw and tighten.

Aw, I thought I had come up with a really good idea here.

[PRNDL]

Enzo and PRNDL - if you don't use spacers between the loaded board and blank board does it crush the wires on the back of the loaded board?

The two techniques are:
- use a spacer nut with two screws: one through the chassis and the other through the board.
- use a long screw with 2 or 3 nuts. One above & below the board to hold it up, and an optional one to bolt the screw to the chassis.

The second technique may be preferred because it's simpler to stock common parts (nuts and screws). Production amps, however, usually use a standoff nut, which makes it easy to get the board the exact same height on all four corners. There's a small price difference between the two (the spacer nut is one or two cents more expensive, if I remember correctly).

It is necessary to have the board above the chassis to avoid electrical connection from the chassis to the component leads. Also, some layouts run wires underneath the board.