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Electronics => Beginners => Topic started by: Chris Wilson on August 27, 2013, 12:22:14 pm

Title: Source of very thin hard plastic tubing?
Post by: Chris Wilson on August 27, 2013, 12:22:14 pm
I want to make spacers out of thin plastic tube to space LED's off a PCB. The PCB will mount behind a metal front panel on short hexagonal stand offs. The LED's will be spaced off the PCB with their leads left about 20 mm long. I want to slip hard plastic tube over the leads, so when the inevitable happens, and someone presses on an LED where it protrudes through a front panel hole, it won't easily cripple the leads and it regress back inside the cabinet. I thought of Biro ink tubing, but am I missing a better and cleaner source? Thanks.
Title: Re: Source of very thin hard plastic tubing?
Post by: fcb on August 27, 2013, 01:05:35 pm
very thin hard plastic tubing - surely an oxymoron.

I've used plastic pcb spacers on LED's before (very cheap from Rapid), but not at 20mm, you could always look to something like 4mm air-tubing, thats pretty stiff but will have a large radius bend in it (which probably won't hurt at 20mm).

I would consider light-pipes over SM LED's though.  My favourite source: www.toby.co.uk (http://www.toby.co.uk)

Title: Re: Source of very thin hard plastic tubing?
Post by: notsob on August 27, 2013, 01:18:17 pm
you can also place a length of clean (no copper cladding - or etched off) FR4 vertically between the LED leads
Title: Re: Source of very thin hard plastic tubing?
Post by: cowana on August 27, 2013, 03:09:55 pm
Why not go with a premade solution? It means you don't have to cut lots of tube to *exactly* the same length...

http://www.toby.co.uk/content/catalogue/products.aspx?series=LED-xx (http://www.toby.co.uk/content/catalogue/products.aspx?series=LED-xx)

Cheers,
Andy
Title: Re: Source of very thin hard plastic tubing?
Post by: jaxbird on August 27, 2013, 03:53:43 pm
You could try some teflon (PTFE) tube, it's fairly rigid and likely what the ink tubes, you mentioned, are made of.

Title: Re: Source of very thin hard plastic tubing?
Post by: Chris Wilson on August 27, 2013, 04:01:17 pm
The pre made spacers or light tubes look tempting, I have to say, plus with me being in the UK their source is convenient, too. I'll do some measurements....  :) Thanks!
Title: Re: Source of very thin hard plastic tubing?
Post by: Paul Price on August 27, 2013, 05:34:49 pm
I simple drill the holes for the LED's so they can be press fit and then apply a tiny swab of Alphacynacrylate (superglue) (just a tiny drop on the rear of the front panel holding the LEDs)and they stay strongly in place.