Glyptal engine paint??
Hey BP,
I like the brass brushes so I can really control the amount of material I remove, not just dirt but casting flash. Also, the brass leaves a slight brassy coloration so it's easy to see where I've already cleaned. Mainly I use brass on aluminum parts to minimize any bozo moments. For cast iron I'd use stainless or brass.
Of course hot tanks are great. I start every engine build with a hot tank jam session thanks to my friend Gary who works in a large shop. But I still do the same previously mentioned cleaning process after hot-tanking. The application is so critical that you really need to be sure about the cleanliness of the metal. It's amazing what you can remove on surfaces that you might think are already clean. Once you spend a few long winter evenings pouring through your parts with magnifying goggles, brass brushes, coffee filters, and alcohol you'll be amazed how much junk still hides in there after a hot tank cleaning. What's hiding in there? Carbonized oil deposits. Especially in oil galleys. Perhaps it's OCD? Maybe. But I like knowing that I did the very best I could.
I knew a guy once who swore off Glyptal because his idea of prep was WD-40, which did a nice job of compounding an already poor application. I don't think he even baked it. Yikes. I think it's people like that who give Glyptal a bad name because they'll go around bitching about it. People like to complain more than they like to compliment.
As to whether or not Glyptal is necessary, that's just up to the builder. I like it very much because it's nice to open an engine and see how clean it is. There's satisfaction in knowing that it does its job. But hey, if you see no benefit then just don't use it. Glyptal arguments are as old as Egypt. All I can say is everyone that I know who uses it correctly loves it. But it's all up to the builder. And again, most of the engines I work on are air-cooled aluminum so they really get quite hot. If/when that engine comes back at any point in the future it's nice to just clean it out with a rag and some mineral spirits instead of having to go through the process all over again.
But like I said, it's not to be found in most production environments simply because most professional builders have work to do and can't obsess over the cleanliness like I can. Besides, I don't think anyone would pay them $***/hour to do it because it's so time consuming. It's one of the few places where if you build engines as a hobby you can really do some nice things that most production shops simply can't offer just because they need to keep the turnaround going. You can't pay anyone to obsess over your project for you.
So I guess I'm up to $0.04 now. Sorry.
I am wondering why brass brushes? Good info and experience. Hot tanks don't care too much ...
