I scored a bunch of material that appears to be phenolitic board. It is from a bunch of materials that were used by an old time ham radio guy. It is like big pieces of perf board material but thicker and darker color. Some is 1/4" thick and brick red on the face and deep mahogany color on the side. The face of it is smooth as glass. If you look at in the light, just right, there appears to be a weave pattern imbedded in the material. An edge on one board is chipped and it came off in layers. Some other 1" blocks and slabs are a very deep maroon color with the imbedded weave under the gloss surface. It can be drilled and machined. It is very dense and hard, almost like aluminum.

Phenollytic?? Use it for spacers between the carb and jug? How about machining an intake mainifold from it? If it is phenolitic board, is there any dangers with sanding dust, asbestos or other nasties?

You got it

Sounds like phenolic to me. Usually the reinforcement was paper but if you see weave, then cotton, nylon or glass may have been used. If you burn a small piece and it smells like hot brake pads (old type), then it again is likely phenolic. I would not breath the fumes from burning or the dust from machining the material. I would look up the safety data sheets for it and see what hazards it presents. Phenolic is a thermosetting resin and a good electrical and heat insulator, and withstands pretty high temperatures. A fire resistant type (FRPP) was ultimately developed before it was replaced by glass epoxy board (GRE or G10) for higher end printed wiring boards.

Some guys build control horns, etc. from that material, I believe.
Back in the old radio age ( real radio..not r/c ) that board was the main insulator material used. Unfortunately, I remember it well.
Rich

I have made two PHENOLIC LINEN carb twisters on Featherlite gas coversion engines. The insulative properties raises the intake air density, making the carb work much better and increasing power. I think it also prevents vapor lock, as my experience showed restarting the engine with an aluminum block was almost impossible. Here's some pics, one of them shows the phenolic block. Machining fine details in the material, such as the vacuum pulse port channel was easy. Also, tapping the material was straightforward and the threads were sufficiently strong to withstand reasonable torque for mounting the carb.

The other pictures show engine mods I did to raise the compression ratio and to lighten the con rod. Net increase from baseline was 150 RPM. This engine is now running sucessfully on a Seagull Models 120 sized Decathlon with PLENTY of power. The featherlite motor is a 25cc. Did any of you know that the effective displacement of a two-stroke gasser is not really 25cc? It's more like 20cc because the exhaust port is open for part of the piston upstroke. Real compression doesn't really start until that port is closed off.