[belcom]

Guys, I ordered the metal parts for my DISA valves but really need to find the concentrated formic acid (98%-100%). I just need a very small amount enough to glue the two casings. Maybe like 5-10ml I suppose. Chemical companies in Canada are not willing to deal with a retail customer at all, basically being total a$$holes about it, no exceptions allowed blah blah. And nobody really sells it over the counter.

Can anybody help me source it please? Perhaps you've done the job and have some left over?

[bluewater328]

Ebay. That's where I got mine. They do the hazardous material declaration on their end. Put more than you think to make sure the whole surface bonds well.

[belcom]

Originally Posted by bluewater328

Ebay. That's where I got mine. They do the hazardous material declaration on their end. Put more than you think to make sure the whole surface bonds well.

I did look at ebay. will spend a bit more time looking there. got a link and seller where you got yours?

[bluewater328]

Originally Posted by belcom

I did look at ebay. will spend a bit more time looking there. got a link and seller where you got yours?

Well, maybe it's just a Canada shipping thing. But there are plenty of sales for Formic Acid

https://www.ebay.com/itm/192570974501

[stevesingo]

I'm struggling in the UK to find 95+% Formic Acid, 85% seems to be the maximum available. Has anyone had success with 85%?

[bluewater328]

Originally Posted by stevesingo

I'm struggling in the UK to find 95+% Formic Acid, 85% seems to be the maximum available. Has anyone had success with 85%?

I'm thinking you'd be fine. They also sell 99%. I've heard of a few people doing some slightly less effective methods (like literally heating up the edges to near melting) and then sealing the outside with gasket maker. If you're worried about the seal staying together, there is enough room to have ghetto tape wrap around the housing - I did it when I first tried it because I was paranoid about it coming apart.

The key to look for is that it is doing a slight chemical melt so it can smooth out and bond.

[belcom]

I found a small amount through a friend of a friend who works in a lab. 96%. hope 10ml is enough.

Bluewater328, did you put the acid on both halves or just one side of the box before merging them?

in the instructions here they say only to put acid on one side:
https://vanos-bmw.com/product/repair...n52t-n51-small

I am doing mine because I want to track the car and really don't want to think twice about a piece of plastic blowing up my engine so a proper seal is important for me without any ghetto solutions

[bluewater328]

Originally Posted by belcom

I found a small amount through a friend of a friend who works in a lab. 96%. hope 10ml is enough.

Bluewater328, did you put the acid on both halves or just one side of the box before merging them?

in the instructions here they say only to put acid on one side:
https://vanos-bmw.com/product/repair...n52t-n51-small

I am doing mine because I want to track the car and really don't want to think twice about a piece of plastic blowing up my engine so a proper seal is important for me without any ghetto solutions

I would personally put on both sides, but its more about putting enough. You really want that chemical to start working the plastic so it bonds together. The melting also blends away minor imperfections in your separation. Think of it like bonding clay. Don't put a thin layer, put a good helping (but stay safe and don't slather it everywhere, it's still acid). Bond it and clamp it together tight for 24 hours. Try to have the clamps evenly around the perimeter as having too much pressure (or not enough) on one side will lead to lifts and weaker bonds. Remember this thing is gonna be activating constantly, so if you don't keep the shells properly together, the gear and the motor will shift. Serious talk though, protect your hands and eyes well.

BTW the newer designs of the large one already have the metal shaft. Smaller one still comes with plastic IIRC. When the unit goes bad, even the metal ones have potential to go bad. The shaft will try and separate from the gear below and I had about a cm out the top. If servo goes, servo goes...can't help that part if its worn.

[belcom]

Originally Posted by bluewater328

I would personally put on both sides, but its more about putting enough. You really want that chemical to start working the plastic so it bonds together. The melting also blends away minor imperfections in your separation. Think of it like bonding clay. Don't put a thin layer, put a good helping (but stay safe and don't slather it everywhere, it's still acid). Bond it and clamp it together tight for 24 hours. Try to have the clamps evenly around the perimeter as having too much pressure (or not enough) on one side will lead to lifts and weaker bonds. Remember this thing is gonna be activating constantly, so if you don't keep the shells properly together, the gear and the motor will shift. Serious talk though, protect your hands and eyes well.

BTW the newer designs of the large one already have the metal shaft. Smaller one still comes with plastic IIRC. When the unit goes bad, even the metal ones have potential to go bad. The shaft will try and separate from the gear below and I had about a cm out the top. If servo goes, servo goes...can't help that part if its worn.

Thank you, appreciate your input.

[Sik328i]

I did rebuild the small DISA valve with the aluminum kit before installing the 3si on my 328i. Highly suggest it. Pretty simple and didn't have any problems getting the acid to reseal the casing (ebay like $5), going to replace voltage regulator on alternator in a few days, so probably going to rebuild large DISA at same time.