Glyptol

[Jim Becker]

I am not a chemist, don't even pretend to be one. So I don't know what I am talking about. But my layman observation is that all these high-tech coatings that cross-link and become impervious to every substance know to man are fairly recent (at least commercially) developments. Glyptal has been around forever. I'm inclined to believe the information supplied by manufacturer. Any permanent effect from heat curing has to be minor and largely coincidental.

Again, not a chemist.

[bob in CT]

Glyptal was one of the first generation of thermosetting polymers, like bakelite, which was developed in the 1930's in New Jersey. I used to drive by the old factory with Bakelite spelled out on the smokestack. Glyptal was originally developed by GE as an electrical insulation for coils, etc. It would not surprise me if it was modified as I thought that environmental concerns were one of the reasons given at the time for spinning it off but I think it just was too small of an operation to be of interest to them anymore especially since the "electric" part of GE had been supplanted by technology and loansharking at the time.

[les king]

Was not intending to respond, I took about an Oz of coolant front my engine, that's been in over a year. The lowest temp I'm capable of bringing it down to was 8 degree. Below. As an antifreeze it works. Now my concern is, if zink or any metals, will break down a coolant and become harmful to an engine, maybe I should build a bigger shed to house my cubs. The expense of taking all apart and applying glyptal would cause a bitter battle with the wife. Just kidding of course. The zink thing was a discovery and I don't see the harm. Palmer Marine thinks it worked. Good conversation, enjoying the responses.

[Lt.Mike]

I would try a needle scaler if you have access to one first.

I second this!
I have basic sand blasting equipment (a cabinet and a small tank) which works but makes a mess and sand gets into places you'd rather it not.
I also have two needle scalers sold by harbor freight. Some of what they sell is junk but the larger of the two scalers is my first choice now for rust and paint removal. The smaller unit they sell doesn't work as well and the larger sells for under $50 so go with that one.
You'll be glad you did. Try it out approaching the surface from different angles and you'll be surprised at how well it works. Doesn't make a mess either as the material just drops instead of being thrown all over (or into your forehead as a wire brush will do).
Mike

[BigBill]

Glyptol is used to seal the sand into the castings from the mold. We hot tanked the engine blocks first to clean them. Once the block is dry we paint the castiron.

I did a test using rustoelum paint. We applied it, then thought we test it so in the hot tank it went. The hot tank couldn't remove it. I later tested a gm six cylinder head with rustoelum white paint. Removed the valve cover down the road to adjust the valves and the paint was still there.

[inairam]

I took the cap I used to flow coat the bolster and recoated it after the acetone air dry test. I let is air dry for 4-5 days and put it in the oven at 250 for a and hour or so let it cool over night.

I redid the q tip acetone wip and the q tip discolored but the coating was not coming off as much as the air dry sample did.

I think Bob is right. There may have been a formal change at some point between the older GE manufactured Glyptal and Glyptal manufactured Glyptal. The oven cure on the current coating may be doing something like sealing the surface/ closing up any pores which is protecting the coating for a period.

Only time will tell. In 20-30 years when the next owner pulls it apart, they can update the thread on how the Glytpal held up.