Hi. I'm not at all familiar with what is available in terms of caps for tactile switches. I attach a picture showing a row of tactile switches on a PCB itself on base plate, (body of tactile switches 6mm square and the button / plunger part about 4mm diameter) and above that a top plate. The caps would protrude thru holes on the top plate so pressing on the cap will push on the switch button. I have not put it on the picture, but the distance between the two sheets or plates will need to be about 30mm (1 1/4"). What options might I have? Of course, the caps must not be able to fall out beyond the top plate. Thanks. Rich

 

i don't think you will find a ready made solution for this application. It would not be difficult to make them yourself, using plastic rod and tube. I have made my own on several occasions.

 

i don't think you will find a ready made solution for this application. It would not be difficult to make them yourself, using plastic rod and tube. I have made my own on several occasions.

Yep, I was thinking this might call for a homebrew solution. So, it seems I was thinking on the right lines. But, if I put a much smaller panel just above the switches (say 7mm above the PCB and only covering the area where the switches are), things might be different - I guess. Rich

EDIT1: The issue, to some degree, is whether a cap is made that actually fits over the plunger. One suspects not, because that would tend to inhibit the plung action.

 

Search for tactile switch cap.

This one is 22.5mm tall.
https://uk.farnell.com/multimec/1s09-22-5/cap-black-22-5mm/dp/1132919

You can get height extenders, 5-10mm.
https://uk.farnell.com/multimec/2s09-10-0/extender-10mm/dp/1132920

Datasheet
http://www.farnell.com/datasheets/11765.pdf

 

Hi. One thing I forgot to point out: I cannot choose the tactile switches, they are on a commercially made PCB. The base seems to be 6mm x 6mm and the diameter of the plunger about 4mm. That makes the solution more problemmatic, unless I go homebrew. The product given is the kind of thing I'd go for probably if the whole project was homebrew. The cap part for the product given seems to accept a 6.5mm dia. plunger. I'd be after a cap that fitted a 4mm plunger. It's looking like I'll need to homebrew the cap.

 

Further: I'm looking at a product data sheet that says " PTS645 Series6 mm Tact Switches " So, the size is 6mm x 6mm (the base). I see that the plunger is 3.5mm dia., which might be the usual size of plunger for a 6mm switch. Not sure though if this info. helps me.

 

The caps don't have to fit over the plunger. You can fill in the bottom of the caps with epoxy so that they rest on top of the plunger.

If you have access to a 3D printer you can print your own caps.

 

There seems to be a number of versions of 6 mm square tactile switches with different lengths of button.
This is a picture of three versions.


The right hand one has a button about 6 mm long and about 3.5 mm diameter.
A few weeks ago I had a similar situation. I made the button extensions from some 8mm diameter aluminium rod.
In one end I drilled a 3.5 mm dia. hole 4 mm deep. The other end I turned down to 4.8mm to fit into 5 mm holes in the panel.
Make the distance from the end with the hole to the shoulder 4 mm longer than the distance between the top of the button on the switch to the underside of the panel.
This shows the extensions fitted.

Les.

 

Here is my solution #1. The grommets stop the cap from sliding out of the top panel/ sheet. And the caps are drilled at one end with a 3.6mm dia. drill. so the cap "locks" into, to a certain degree, with the switch plunger.

 

Here is how they did it on the DSO138 oscilloscope acrylic case.







Other schemes:





https://www.instructables.com/Oscilloscope-DSO138-Case/