Full Version: What to Spray on the Bottom of Relay Board
What type of sealer should I use on the bottom of these?
Use liquid electrical tape... You can get it a home depot, stuff works great for that application. I've done 2 boards using liquid electrical tape.
Good idea! 
I tried that earlier and it just ran off the copper. I will try cleaning it with lacquer cleaner and see if it will stick.
I have been using an aircraft grade expoxie that has been on the relay board for about 14 years now. No problems yet.
KP
KP
A good electrical parts store might sell you a small amount of conformal coat which is what is used today on almost all boards. This would be what I would use as the first step to seal the board traces from corrosion. I don't know if you need anything after the conformal coat to strengthen the board so it doesn't flex? I'm guessing maybe that's why Porsche used the goop they did. 
What did you clean the traces with so the solder would flow?
What you want is what the electrical guys call "potting compound". Comes in silicone and epoxy and is used to "pot" or seal electrical components. Comes in conducting and nonconducting. We want nonconducting.
Some types have a self leveling feature (low viscoscity) so it will ooze across the board and create a level pool. This is what we want.
Potting compounds used to be silicone, but epoxies are used a lot now. To my way of thinking, this is a 30 year old car and the potting compound may need to be removed later for another fix. Silicone is much easier to dig out than epoxy, so I would suggest silicone.
Searching silicone potting compound prices turned up this linky for $18 a tube.
Linky fixed
Ken
Some types have a self leveling feature (low viscoscity) so it will ooze across the board and create a level pool. This is what we want.
Potting compounds used to be silicone, but epoxies are used a lot now. To my way of thinking, this is a 30 year old car and the potting compound may need to be removed later for another fix. Silicone is much easier to dig out than epoxy, so I would suggest silicone.
Searching silicone potting compound prices turned up this linky for $18 a tube.
Linky fixed
Ken
Hmmmm it ran off the copper,,,, did you use a spray version of that. I used the liquid tape that had to be brushed on. Never had such a problem using it.
Dave Shepard and Glenn Stazak used to use a two part potting epoxy that worked good.
QUOTE(kwales @ Jan 18 2009, 09:38 AM) 
What you want is what the electrical guys call "potting compound". Comes in silicone and epoxy and is used to "pot" or seal electrical components. Comes in conducting and nonconducting. We want nonconducting.
Some types have a self leveling feature (low viscoscity) so it will ooze across the board and create a level pool. This is what we want.
Potting compounds used to be silicone, but epoxies are used a lot now. To my way of thinking, this is a 30 year old car and the potting compound may need to be removed later for another fix. Silicone is much easier to dig out than epoxy, so I would suggest silicone.
Searching silicone potting compound prices turned up this linky for $18 a tube.
Silicone Potting Compound $18 a tube]Silicone Potting compound linky[/url]
Ken
Ken, the link says it is broken. Can you redo it please. I would love to see what this stuff is.
QUOTE(Phoenix 914-6GT @ Jan 18 2009, 12:17 PM)
QUOTE(kwales @ Jan 18 2009, 09:38 AM)
What you want is what the electrical guys call "potting compound". Comes in silicone and epoxy and is used to "pot" or seal electrical components. Comes in conducting and nonconducting. We want nonconducting.
Some types have a self leveling feature (low viscoscity) so it will ooze across the board and create a level pool. This is what we want.
Potting compounds used to be silicone, but epoxies are used a lot now. To my way of thinking, this is a 30 year old car and the potting compound may need to be removed later for another fix. Silicone is much easier to dig out than epoxy, so I would suggest silicone.
Searching silicone potting compound prices turned up this linky for $18 a tube.
Silicone Potting Compound $18 a tube]Silicone Potting compound linky[/url]
Ken
Ken, the link says it is broken. Can you redo it please. I would love to see what this stuff is.
I think this is what he was trying for.
Silicone Potting Compound.
Potting compound works well.
I used Black RTV, and it is still good
I used Black RTV, and it is still good
There is a thread on Roadglue that covers this. I have seen this material and I think this is the best solution. This is as close to the original material as you will get. I don't think RTV is the best because some of these outgas corrosive vapors.
Relay board repair
Relay board repair
Just my 2 cents but usually any silicon has ammonia in it. NOT GOOD FOR TRACES. We use a product called 3 bond for sealing. No ammonia but takes longer to dry. Epoxy once cured is always good. ( PS. i repair CNC equipment, so waterproofing is very important!). 
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