What is Liquid Graphite?

[Gavin Chafin]

We just received the rules for our Pack's Pinewood Derby. One of the rules is "No Liquid Graphite." I've never heard of this. Anyone know what liquid graphite is? Or do you think they meant to say "No liquid lubricants"?

[MaxV]

They could have meant "No liquid lubricants". But I'll bet they were referring to liquified graphite. This is graphite that has been mixed with isopropyl alcohol (or another carrier). The fluid can be applied with a paintbrush or an eye dropper. The alcohol evaporates quickly leaving a coating of graphite.

I have played with a few brands, and made my own. But I was not impressed. The coating of graphite is generally too thick, so it tends to gum up the works. For pinewood derby cars, graphite works best as a powder.

[terryep]

I've played around with regular graphite quite a bit. If you pour it into the axle space and roll the car back and forth with a 500g weight on top repeating with more graphite and rolling eventually you end up with is an actual bearing made of graphite! I found this out after dissecting the wheels after the racing season was over 2 years ago (a grey cylinder fell out). A light dusting of graphite right before the race will give the best results. The car will loose some of its speed after a few dozen races but the bearing will get you through the next 50 races! I fear to think what would happen if one of these bearings ever shattered!

Terry

[Splinter Sprinter]

We tried “paint on graphite” last year. I was so jazzed when I bought it, I thought I discovered the Holy Grail because of its touted proprieties. Its particle size is equal to or less than 2 microns in size. It was colloidal graphite so it flowed with its isopropyl carrier to the smallest of places, like inside of the wheel hub.

We used the type pro photographers use on their camera diaphragms. We painted all the contact points, the axle, wheel hub, wheel tread and the sides of the car that might come in contact with the hub. We buffed it all to a shining silver-black with a cloth jeweler’s wheel and Dremel. I thought since this stuff stays put, unlike the powder graphite, my sons car could run all day and not lose speed.

It didn’t do as well as we thought it would in test runs. I think it worked best on the plastic surfaces but not on the axle. Maybe if we just put it on the wheels and left the axle alone. We dropped it and changed to a lightweight food grade silicone that worked well.

All in all I think it was a good learning experience for my son, to not except status quo and try new ideas.

[Alex]

i agree with Randy. One time I saw where Stan Pope sugested mixing rubbing alchohol with draprite so the graphit would run down into the contact area without havinging to take off the wheel to get the graphite in.

[Stan Pope]

i agree with Randy. One time I saw where Stan Pope sugested mixing rubbing alchohol with draprite so the graphit would run down into the contact area without havinging to take off the wheel to get the graphite in.

I don't remember making that suggestion. Perhaps you have a better memory than I do. Perhaps, even your memory is a good as my kid brother's... he even remembers things that never happened!