HTP 221 took a dive yesterday.

[ryanjones2150]

Maybe. There is definitely thermal paste on the IGBTs where they mate to the back plate of the housing they’re in, it’s a gray tone paste similar to what I’ve used before. The same paste is used between the aluminum back of the housing and the large heat sink inside the machine. If I can’t get something close to what I see in there then I may just fill it with the thermal paste after I verify it’s non-electrically conductive I’d think. I don’t really know, this is new work for me. I may see if I can call the manufacturers of those compounds you linked, Melted.

[Sberry]

You are doing better than I would. All that crap is a blur to me and dont know an olt from a vohm or what an igbit even is. It will be interesting to see if you can fix it.

[ryanjones2150]

Well as long as you know wamps from atts, you’re a step above me!

I think I might have found a solution to the clear schmoo. I’m waiting to hear back from the manufacture on their recommendation, they have lots of different products under the Molykote line. This is a link to one that MAY suffice if anyone is interested:

https://www.dupont.com/products/molykote-5-compound.html

[Sberry]

I really dont know anything about electric. I did manage to find a broken tail light wire yesterday, felt like a super fricken hero.

[ryanjones2150]

One small step for man, one.....somethin’ somethin’......

[Sberry]

I hate all that trouble shooting with a passion. When I get too many wires or all those small electron moving parts I got to call my helper. He recently moved and living with a sister, I really miss someone to bounce my tech problems off in the mornings. I try to keep the phone calls to a minimum and fix most of my own problems. I had to go fix a limit switch, look for parts the other day and it was almost above my pay grade.

[ryanjones2150]

It’s good to have people in your network that can share their skills for sure.

[Burnt hands]

The clear stuff might be conformal coating.
We it to cover PC boards which were going to be used in
very humid and hostile environments.

Used xylene to thin it before it cured but after it cured only mechanical means worked.
Dremel with a wire or bristle brush seemed best to get it off without too much damage to board.
Believe it was made by Corning but don't know the number.

Good luck

[ryanjones2150]

Thanks BH.

[Sberry]

I am trying to keep it alive here so we stray a little. My way back Bud has lived here a couple times and recently left to live in the city with a sister. When he wants to be is one of the best hands on mechanics even real engineers would appreciate. Got a gift for "putting his finger" on the problem. I have seen real smart people over think it but listen to an engine and determine the timing key had sheared and slipped up or some hose you cant even see on the back and be able to rewire gobs of controls etc.
I dont really call the heating guy or the machine maker etc or the dealer, I got a tech I have take a look see when I need a mind greater than my own.
Note the record player with the wire, as I recall this was for some obsolete transformer. We got quite a collection but something strange as I recall we couldnt find maybe. Made a repair to some board with a wall wart transformer not too long ago.

[Sberry]

I am trying to keep it alive here so we stray a little. My way back Bud has lived here a couple times and recently left to live in the city with a sister. When he wants to be is one of the best hands on mechanics even real engineers would appreciate. Got a gift for "putting his finger" on the problem. I have seen real smart people over think it but listen to an engine and determine the timing key had sheared and slipped up or some hose you cant even see on the back and be able to rewire gobs of controls etc.
I dont really call the heating guy or the machine maker etc or the dealer, I got a tech I have take a look see when I need a mind greater than my own.
Note the record player with the wire, as I recall this was for some obsolete transformer. We got quite a collection but something strange as I recall we couldnt find maybe. Made a repair to some board with a wall wart transformer not too long ago.

[Sberry]

It sucks, I miss not being able to toss it on the bench or have someone over my head take a look. I went to the problem on a job today, took me a little longer but resisted the temptation to call for help and got thru it.

[Sberry]

We were standing around a while back and gonna fiddle with an old car, a turn sig switch maybe. Its an old car and depreciated but its gotta work and the store in now only 10 minutes each way so,, they got it 28$ as I recall, I just check which I usually do. 20 minutes in a car if I wanna fix it which I do as we are picking our nose a little and wanna get past it so,, I pull it out, look a second and hand it to my bud and turns out it had some dirt in it and a pin or contact or something bent. Rest of it like new, had it back in my hand in about 10 minutes while I got a coffee.
Sometimes I ask,,,, how long? Not everyone fully appreciates parts repairs. We used to fix tv and vcr, wouldnt dream of that kind of service repair today and often not even to expensive sets.
But I cant run to the store everytime something doesnt start and buy a replacement part, the cost, the time. We fix a fuel reg to a gen set today, I didnt look ebay for replacement. Didnt look for a "kit", it came apart fine and turns out there was a bug got in it.

[ryanjones2150]

Well I hope I can get these IGBTs back in, refill the schmoo, button it up and she chooches like new, for a while at least. But my luck, there’s some other part on the board that caused the IGBTs to quit on me and when I put power back to the machine she’ll just let the smoke out again. That’s the likely outcome. Then I’ll be in it for a new board because I need this machine. But if I replace the board, I’ll probably put this machine up for sale and get something else in its place. I hold grudges.

[Sberry]

If i got it working would run it to the end.