Hi. I'm wanting to affix plastic PCB supports to a 5mm thick piece of acrylic (plexiglass) - i.e, the chassis. My pcb has holes 3.2mm diameter.

a) It's not proving easy to find a support that will attach by the most common method, which is where you push in the support through a hole and plastic "wings" spread out at the backside of the chassis. Because of the chassis being 5mm thickness.

b) There are blind hole types, that you simply push into a blind hole. But, I've not yet been able to find a product whose minimum chassis thickness is less than 1/4" (6.3mm).

c) There are supports with bases that stick to the chassis.

I suppose I might be able to "get away" with doing b). But the support will protrude at the back of the chassis.

Otherwise, I'm left with option c).

Any thoughts or recommendations? Thanks.

 

Use hex female threaded stand-offs, with 3 mm threaded holes.

Use M3 screws of the correct length.

 

Oh, I forgot to mention. I'm wanting snap-on only solutions.

 

Oh, I forgot to mention. I'm wanting snap-on only solutions.

You will likely need to go another direction..
Or can you counterbore your chassis holes to reduce overall thickness?

 

Oh, I forgot to mention. I'm wanting snap-on only solutions.

If these are to be permanent, you can use glue on the ones that are too short for your material. Just don't use one of the 'super glue' types if the acrylic is clear, it tends to cause 'frosting' on acrylic.

 

You made your mis

Hi. I'm wanting to affix plastic PCB supports to a 5mm thick piece of acrylic (plexiglass) - i.e, the chassis. My pcb has holes 3.2mm diameter.

a) It's not proving easy to find a support that will attach by the most common method, which is where you push in the support through a hole and plastic "wings" spread out at the backside of the chassis. Because of the chassis being 5mm thickness.

b) There are blind hole types, that you simply push into a blind hole. But, I've not yet been able to find a product whose minimum chassis thickness is less than 1/4" (6.3mm).

c) There are supports with bases that stick to the chassis.

I suppose I might be able to "get away" with doing b). But the support will protrude at the back of the chassis.

Otherwise, I'm left with option c).

Any thoughts or recommendations? Thanks.

You made your mistake by not designing the mounting system along with the pcb. Now you are stuck with 3.2mm holes. You might be able to make them bigger. Harder to make them smaller.

Check out something like this used for PC system boards.

http://www.ebay.com/itm/like/182684891501

 

I'm actually trying to affix an arduino UNO board to 5mm thick acrylic sheet. Hole size on the arduino board is given as 3.2mm.

Those reverse snap -on standoffs, are great, but I've not seen one of that type that will snap onto a 5mm thick chassis. If fact, I've not seen any type of snap-on pcb standoff that will clip onto a 5mm chassis.

I'm trying to avoid the standoffs that you have to glue - if I can.

At the moment I'm thinking of using a blind-hole type, and placing a spacer either on top of the chassis, so the plug part does not protrude from the chassis, or, place the spacer on the underside of the chassis, effectively attaching onto the protruding part. Where I'm drilling the chassis right through. Because the chassis is thinner than recommended depth of the blind-hole types I've seen so far.

I suppose the former is better. Because there might be only 2mm or so of the plug protruding.

 

I'm actually trying to affix an arduino UNO board to 5mm thick acrylic sheet. Hole size on the arduino board is given as 3.2mm.

Those reverse snap -on standoffs, are great, but I've not seen one of that type that will snap onto a 5mm thick chassis. If fact, I've not seen any type of snap-on pcb standoff that will clip onto a 5mm chassis.

I'm trying to avoid the standoffs that you have to glue - if I can.

At the moment I'm thinking of using a blind-hole type, and placing a spacer either on top of the chassis, so the plug part does not protrude from the chassis, or, place the spacer on the underside of the chassis, effectively attaching onto the protruding part. Where I'm drilling the chassis right through. Because the chassis is thinner than recommended depth of the blind-hole types I've seen so far.

I suppose the former is better. Because there might be only 2mm or so of the plug protruding.

Drill the outside of the acrylic sheet with 0.25" to 0.375" Forsner bit (flat bottom) and drill deep enough to leave only 1/8" of material. Then drill the hole for your winged mounting pegs.

 

Whats wrong with a nylon female-female round or hex standoff? screw on outside of chassis.. nylon screw on component side of Arduino..
If you want flush on the outside of the enclosure use a flat head screw/countersink..