Using Graphite for a carb spacer

[Anonymous]

Has anyone thought about using graphite as a material for a spacer plate? Im making one right now and my only concern would be the residue that easily comes of the plate. Same thing as touching a freshly sharpend pencil, graphite dust. I was wondering if this "dust" would enter the chamber and cause damage to my valves or anything else. Also I was thinking that an easy way to fix this would be to just paint it with high temp paint.
Any thoughts?

 

[XFlow_Fairlane]

are you talking a block of graphite or carbonfiber?

nick

 

[addo]

Pure graphite is pure carbon. Can't paint it. Crumbly in larger pieces.

Carbon fibre is pretty good, but something else altogether. Not cheap to pressure mould.

To make it yourself, I suggest Phenolic - buy a thick chunk and machine away. Durable, gets a good finish, easy to machine.

Regards, Adam.

 

[Anonymous]

why cant you paint it?

Ive already did the machineing but there is a residue on it that when you touch it leaves black marks on your hand. will this carbon residue harm the engine?

Thanks

 

[MustangSix]

Graphite is like the stuff pencil lead is made from. Soft, crumbly. Are you sure that's what you have?

One of the faster guys I knew back in the 70's had a trick material for carb spacers. Easily cut, drilled and worked, cheap, commonly available - plywood. It insulated the carb better than aluminum and when properly sealed, lasted a long time.

 

[Anonymous]

well how about i just make a 2bbl carb adapter out of wood now

 

[Anonymous]

yes its the same thing used in pencils. But no it is not too soft, nor is it crumbly. It is worked with in the same way wood is, so its easy to work with. It may chip if it were droped but I hold on to it pretty good. Its always cold too.

Wood is a great insulater for a spacer and seals well, in fact they sell it on summit and other catologe companies. However, I wouldnt recomend making an adaptor out of it, spacer is fine but an adaptor would seem too complex for wood.

About the residue issue. Im thinking there won't be much of a problem with graphite powder going into the engine. After all it is used in some engine oils.

I should be mounting the carb tomarrow, and will be taking plenty of pics to boot.

 

[Anonymous]

Your comment that it's always cool got me to thinking, and it turns out that graphite is an excellent conductor of heat. Apparently it's widely used in commercial heat exchangers. You might want something that would insulate better. Looks like it conducts about half of what aluminum will, but that's not real precise.

As to the graphite in the oil, I would reccomend that you go to FTE and look in the tech articles for one on "snake oil". It's really really good. Deals mostly with PTFE as a suspended solid oil additive, but I would believe that it would apply equally as well to graphite which is no where near as slick. Also the PTFE would be ground to a much finer level than any that might flake off of your adapter.

All in all, I'd say you need some other material. Phenolic or solid piece of plastic. Big chunk of Nylon maybe?

 

[addo]

Phenolic is one of the best; I said it before, now again. If you can stand the horrible antiseptic smell while hacking it to shape!

Regards, Adam.

 

[Anonymous]

what is exactly phenolic? is purchased relatively cheap? is it easy to work with? I've seen them for sale in various cataloges, but for a pretty penney.

 

[Anonymous]

http://www.sdplastics.com/phenolic.html

Phenolic sheet is a hard, dense material made by applying heat and pressure to layers of paper or glass cloth impregnated with synthetic resin. These layers of laminations are usually of cellulose paper, cotton fabrics, synthetic yarn fabrics, glass fabrics or unwoven fabrics. When heat and pressure are applied to the layers, a chemical reaction (polymerization) transforms the layers into a high-pressure thermosetting industrial laminated plastic.

-=Whittey=-

 

[Anonymous]

Look around at material supply places. Usually where you can buy new and used metals. Seems like you can snag a pretty good sized peice for a couple of bucks.

 

[Anonymous]

I've used "pure" graphite in industial applications we used it for low friction high temperature pillow blocks and other stuff on aluminum extrusion equipment, Yes it is a reasonable conducter of electricity and heat, thats why its used as motor brushes. It is machinable but it is brittle I wouldn't use it, pencil leads are graphite ground fine and mixed with clay in varying degrees depending on what softness, pencil #, you desire they also used to make Carbon pile resistors that used plates of graphite stacked up in a device that had adjustable clamps that comressed them to vary the resistance, they sometimes used "blended carbon".

 

[mugsy]

I worked around graphite too, in an industrial application. It is machine-able and, as the other posts noted, it is a good conductor of heat. Doesn't insulate real well. The stuff I was around was placed 1/4" above molten glass where the glass was 1300 F, but it was in an oxygen depleted environment. Humm, carbon plus heat plus oxygen equals CO2! The stuff we used went thru many heat/cool cycles and would get brittle and chunks would fall off. My prediction is that the spacer will last for awhile but under compression from the carb bolts (no vac leaks right) plus the heat/cool of an engine, it will crumble.

As for the powder, it should convert to CO2/CO in the combustion chamber/process. Don't know if a "large" chunk would be a problem though if it worked its way into the combustion chamber.

Tell us how it works out!!