Author Topic: Spot welding plastic sheets  (Read 3496 times)

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Norm

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Spot welding plastic sheets
« on: October 21, 2011, 02:26:22 PM »
Those plastic portfolios make nice covers for the NiCad batteries....
using a cheap little soldering pen plugged into a light dimmer switch almost works
but even on the lowest possible setting it gets too hot....I could turn it off as soon as
it started getting too hot....kinda unhandy  tho  any ideas maybe a 50 watt incandescent
light bulb in series.....?

Reall  makes a neat looking battery package.
Norm

DanG

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Re: Spot welding plastic sheets
« Reply #1 on: October 21, 2011, 02:32:15 PM »
Hot air welding - for that small of scale use a shroud over the soldering iron with an aquarium air pump as air supply?

TomW

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Re: Spot welding plastic sheets
« Reply #2 on: October 21, 2011, 03:57:21 PM »
Norm;

Lots of plastic parts are sonic welded. They vibrate the plastic at a rate that melts and mingles the 2 parts.

No clue how to do that at home? One of Jerrys amplifiers and a tone generator maybe?

Just a bit of another angle.

Tom

12AX7

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Re: Spot welding plastic sheets
« Reply #3 on: October 21, 2011, 06:42:19 PM »
I've done it with a candle and the head of a finishing nail.

12AX7

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Re: Spot welding plastic sheets
« Reply #4 on: October 21, 2011, 06:50:16 PM »
Norm;

Lots of plastic parts are sonic welded. They vibrate the plastic at a rate that melts and mingles the 2 parts.

No clue how to do that at home? One of Jerrys amplifiers and a tone generator maybe?

Just a bit of another angle.

Tom

I'd not mind getting my grubby hands on one of Jerry's amps..  but I don't think I'd try using them to spot weld!
at least not with a high output impedance (32 ohms?).

Rover

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Re: Spot welding plastic sheets
« Reply #5 on: October 21, 2011, 07:47:43 PM »
Not knowing what the plastic is, I've bonded lots with just straight MEK . Dab will do ya

Pretty much for plexiglass, building filters and beta emitting radiation blockers

... other than that if in US HF has a little plastic weld kit for cheap.

Rover


Rover
<Where did I bury that microcontroller?>

Norm

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Re: Spot welding plastic sheets
« Reply #6 on: October 21, 2011, 09:18:39 PM »
Thanks for all the helpful replys....I wasn't even aware that HF had a kit for this....
and my goodness! a candle and a nail !  I imagine a heavy duty would be a bigger
candle and nail ?  ;)  ....but you're right it doesn't take much heat even to melt the
edge of the nice table cloth which I accidently done as I was unplugging the soldering pencil
( Oh  crap ^(&&%^ ! ....as I hurriedly cut the edge of the damaged area with the
scissors .....she'll never know ?

I had a thought....since the replaceable copper of the soldering tip is like 6 or 8 guage
copper I could use a longer piece and would disappate some of the heat before it got
to the tip ?

Norm

TomW

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Re: Spot welding plastic sheets
« Reply #7 on: October 21, 2011, 09:23:39 PM »

I had a thought....since the replaceable copper of the soldering tip is like 6 or 8 guage
copper I could use a longer piece and would disappate some of the heat before it got
to the tip ?

Norm

I would say "yep" the further the business end is from the iron body the cooler it will be.

Tom

12AX7

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Re: Spot welding plastic sheets
« Reply #8 on: October 21, 2011, 11:52:26 PM »
Just another quick comment about welding plastics.  There are way too many types of plastics to really accurately comment on but one rule of thumb to keep in mind is..   Time Temperature and Pressure and the real trick is to discover the correct combination.

Norm

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Re: Spot welding plastic sheets
« Reply #9 on: October 22, 2011, 12:12:13 AM »
Thanks agin Tom and 12AX7

Norm.