Epoxy / Caulk to secure large components to PCB

Everlast · 18th July 2009, 04:59 PM

Getting near the end (hopefully!) of fixing a subwoofer amplifier for my son.

While doing a final inspection prior to re-assembly, I noticed that two large power resistors (similar to Vishay Dale CPCP07 type)were loose and had broken leads on them (not salvageable). I just ordered some replacements from Mouser (boy it hurts to have to pay $8 shipping for $2 worth of parts but I wasn't able to shop for other items that I could use due to a shipping deadline).

My question is -
What sort of caulk or epoxy would be recommended to secure these large items to the pcb? The other "large" components were secured with a hard, yellowish material, but the two resistors had only a minimal amount of this material applied and had broken free.

Thanks

zigzagflux · 18th July 2009, 07:15 PM

Silicone RTV gets my vote. We used them to support large power resistors and capacitors to the PCB's used in AC/DC drive equipment. Excellent vibration resistance.

Geek · 18th July 2009, 07:41 PM

Quote:

Originally posted by zigzagflux
Silicone RTV gets my vote. We used them to support large power resistors and capacitors to the PCB's used in AC/DC drive equipment. Excellent vibration resistance.

And heat resistance.

Another good adhesive is shoe glue.

Cheers!

Everlast · 18th July 2009, 10:22 PM

zigzagflux -
I also worked at a company that used a special "electronic" GE Silicone RTV for this purpose. The regular stuff you get at the hardware store is not suitable (eats the copper I think).

Since I really don't want to order this special RTV because of time and cost (shipping charges) can you think of anything else?

Geek -
What the heck is "shoe glue"? Can it handle the heat? It will be used to secure a 7 Watt resistor.

Thanks,

Geek · 19th July 2009, 12:24 AM

Quote:

Originally posted by Everlast

Geek -
What the heck is "shoe glue"? Can it handle the heat? It will be used to secure a 7 Watt resistor.

A trick I stmbled across while fixing guitar amps.

Shoe glue is just that - the stuff a cobbler uses to glue the rubber onto the leather part of the shoe. Try a little shoe repair shop.

Can it handle 7 watts? I dunno, but I've seen it handle 2 or 3 watts without losing integrity.

Cheers!

DigitalJunkie · 19th July 2009, 02:41 AM

Quote:

Originally posted by Geek

A trick I stmbled across while fixing guitar amps.

Shoe glue is just that - the stuff a cobbler uses to glue the rubber onto the leather part of the shoe. Try a little shoe repair shop.

Can it handle 7 watts? I dunno, but I've seen it handle 2 or 3 watts without losing integrity.

Cheers!

One brand name that is popular in the hobby community is "Shoo Goo"
Here's a random link from Google:
http://www.weplaysports.com/Shoe/Goo/

Any local hobby shop (RC,models,crafts,whatever) should have some.

Everlast · 22nd July 2009, 02:20 AM

Well I got back some information from the manufacturer of Shoo Goo and I don't think I will use it -

"SHOO GOO HAS ABOUT 0.1% OF ACETIC ACID."

According to the nice gentleman that I talked to, the acetic acid should evaporate after the product is cured, so that doesn't appear to be a big deal.

"CURED SHOO GOO CAN BE EXPOSED FOR SHORT PERIODS TO TEMPERATURES UP TO 150 F. THE CUSTOMERS NEED TO RUN TESTS TO VERIFY SUITABILITY IN THEIR APPLICATIONS."

This 150 F limitation bothers me though. Since my application is to secure a 7 watt resistor, this product just doesn't seem suitable.

I did a little surfing though and it looks like a GE Silicone II product (NOT 1, which contains acetic acid) might work.

Thanks,

gmphadte · 22nd July 2009, 11:28 AM

Use cement type or 2 part type adhesives. Here it's brand is Araldite

18th July 2009, 04:59 PM	#1
Everlast diyAudio Member Join Date: Jul 2009	Epoxy / Caulk to secure large components to PCB Getting near the end (hopefully!) of fixing a subwoofer amplifier for my son. While doing a final inspection prior to re-assembly, I noticed that two large power resistors (similar to Vishay Dale CPCP07 type)were loose and had broken leads on them (not salvageable). I just ordered some replacements from Mouser (boy it hurts to have to pay $8 shipping for $2 worth of parts but I wasn't able to shop for other items that I could use due to a shipping deadline). My question is - What sort of caulk or epoxy would be recommended to secure these large items to the pcb? The other "large" components were secured with a hard, yellowish material, but the two resistors had only a minimal amount of this material applied and had broken free. Thanks

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Can Silicon Caulk damage speakers?	DeadSpeaker	Multi-Way	13	19th January 2009 02:38 PM
How to secure/fix fragile wires to veroboard?	HankMcSpank	Everything Else	10	8th July 2008 07:48 PM
How do you secure your cables inside your cabs?	dublin78	Multi-Way	15	13th March 2008 09:26 PM
Mortite/Rope Caulk for Cabinet Deadening	sdclc126	Multi-Way	37	8th June 2006 11:38 PM
Using rope caulk (mortite) to seal drivers and damp vibrations	percy	Car Audio	0	31st July 2005 03:16 AM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

18th July 2009, 07:15 PM	#2
zigzagflux diyAudio Member Join Date: Oct 2006	Silicone RTV gets my vote. We used them to support large power resistors and capacitors to the PCB's used in AC/DC drive equipment. Excellent vibration resistance.

18th July 2009, 10:22 PM	#4
Everlast diyAudio Member Join Date: Jul 2009	zigzagflux - I also worked at a company that used a special "electronic" GE Silicone RTV for this purpose. The regular stuff you get at the hardware store is not suitable (eats the copper I think). Since I really don't want to order this special RTV because of time and cost (shipping charges) can you think of anything else? Geek - What the heck is "shoe glue"? Can it handle the heat? It will be used to secure a 7 Watt resistor. Thanks,

22nd July 2009, 02:20 AM	#7
Everlast diyAudio Member Join Date: Jul 2009	Well I got back some information from the manufacturer of Shoo Goo and I don't think I will use it - "SHOO GOO HAS ABOUT 0.1% OF ACETIC ACID." According to the nice gentleman that I talked to, the acetic acid should evaporate after the product is cured, so that doesn't appear to be a big deal. "CURED SHOO GOO CAN BE EXPOSED FOR SHORT PERIODS TO TEMPERATURES UP TO 150 F. THE CUSTOMERS NEED TO RUN TESTS TO VERIFY SUITABILITY IN THEIR APPLICATIONS." This 150 F limitation bothers me though. Since my application is to secure a 7 watt resistor, this product just doesn't seem suitable. I did a little surfing though and it looks like a GE Silicone II product (NOT 1, which contains acetic acid) might work. Thanks,

22nd July 2009, 11:28 AM	#8
gmphadte diyAudio Member Join Date: Jul 2003 Location: Dona paula, Goa	Use cement type or 2 part type adhesives. Here it's brand is Araldite