revtothelimit - motorbike forum

The paint has to come off this aluminium swing arm;



Doing it manually will be tedious, so out with the chemicals. MEK to be precise, which I'm assured is what used to be in Nitromors and similar.

Place the arm into a bag with an open pot of MEK and leave to do what it will:



Overnight should do it, or not.

Phosphoric acid is what you want if that doesn't work.

I think.

It's what you'd use on rusty steel.

I've just seen a picture of your shed - why don't you bead blast it ffs?

Because I can be sitting here tryping and drinking tea while the molecules do the work. Delegation.

Or laziness.

The blaster is a bit shite, the suction gun doesn't. The beads are dry, there's plenty of air, no blockages, no one problem I can find, so I'm waiting for pressure pot to arrive.

Just read up on MEK doesn't look like a very nice chemical to be breathing in. Possibly why Nitromors got rid of it. Be careful and get a wire wheel out.

Well that achieved naff all. First I should have used methylchloride, not MEK. So I did. and it didn't do much. It evaporates to quickly to work, even in a sealed bag. I could thicken it, but that'll can wait.

The MEK will come in handy as an acetone substitute.

Time to crack on with the mechanical methods.

cheb wrote: Thu Apr 09, 2020 12:35 pm
The MEK will come in handy as an acetone substitute.

I have some MEK as an acetone substitute. I try never to run out of acetone.

I have a story about using MEK. I might have told it though so I'll keep schtum.

Crack on. If you have told it before I've forgotten it.

I was asked to do a small fibreglass repair on a friend's boat, just a 14 foot open boat and as it was fairly old and all polyester I took polyester resin and MEKp with me to do the job. The boat was in the water, over in the southern, sheltered part of the bay and I climbed in and got all the bits sorted. I was telling Cemal, the owner that MEKp was really nasty stuff - it's why I was wearing gloves and overalls even on a warm day and that you don't want it on your skin and you certainly wouldn't want it anywhere near your face and definitely not in your eyes.

Hassan Hussein stopped by as I was getting set up and was watching what I was doing. He's an old boy, got two big boats and knows his stuff but doesn't really do fibreglass etc. He calls me Usta, Turkish for 'Master'. Anyway, I measured out the resin then filled a syringe with the requisite amount of MEKp. You don't need a lot, just 3% of the resin is usual and I use syringes to get it reasonably accurate. The problem was, when I went to slowly squirt the MEKp into the resin, the syringe sort of stuck. I pulled the plunger back a bit and tried again, sort of expecting it to stick again but of course, it didn't. The shit squirted into the mixing tub and ricocheted off the thicker resin, splashing me in the face. I didn't see Cemal and HH start laughing as I immediately stuck my head over the side of the boat and into the sea but they were still laughing when I came up again. Buggers.

Ouch. I did similar with a pumper carb and petrol

Before:



During:



After:




I've a way to go yet, the coating has a palpable thickness and there's lots of nooks and crannies to fertle in. I've slathered more stripper on and will pressure wash it again after a dish of tea.

Info: I'm using Starchem Synstriyp, it claims to be like old style Nitromors applied with a cut down paintbrush. It's only available to trade users, or anyone that can find it online. So far it seems effective.