Originally Posted by
eric044
Like with most occasions when people try homemade items to replace marketed items the reason regards quality - in terms of both usefulness of the product and environmental. Of course, like with anything else, in my opinion, there are no proven theories, there are different opinions.
Believe it or Not, Ripley (and everyone else here, including me) the castor oil idea might not be that far off.
Green Grease: Environmentally Friendly Industrial Lubricant Developed | CleanTechnica
The process uses cellulose derivatives as thickening agents. The article mentions that the resulting bio-grease is not stable at high temperatures and doesn't stay put very well under high pressure or in high rpm applications, but in the relatively low temp, low rpm environment of a BB, hub, or pedal bearings, or in a relatively static bearing like a headset, it just might work.
OP, if you are insistent on a DIY experiment, your idea of adding glycerine is not completely wacky as glycerine is a common biological soap base, usually combined with steric acid to produce glycerol monostearate, which would indeed emulsify a vegetable oil. It should be available at any hobby or craft shop that carries home soap making supplies. As a cellulose derivative thickener, I'd think that carboxy-methylcellulose might work and is readily available as a food and cosmetic additive. It is commonly used in combination with glycerine and isotonic saline solution as soothing eyedrops (artificial tears). Other possibilities would be polysaccharides like guar gum or xantham gum which are used as thickeners and food texture modifiers. Other bio additives that the OP might want to consider include coconut oil and carnauba wax. The biggest obstacle I see is the relatively rapid breakdown and rancidity of the base oils that might be used. The addition of BHT or BHA in proportions far higher than would be allowed as a food additive, might stave this off. Other big questions are: Will it provide the required lubrication and corrosion resistance? Is it compatible with the various metals and other materials with which it will come into contact? and How would it perform under various cycling conditions of heat, cold, humidity and wet weather?
From a bike maintenance standpoint, I am sticking with my advice to just buy some decent grease and learn proper maintenance. But if the goal is to experiment with creating a sustainable and environmentally friendly product using a bicycle as a test vehicle, what the hell. As noted, pick a cheap garage sale bike that you don't mind seeing destroyed in the process. I still think you will waste a lot of time, money and effort to create an inferior product as, even if you want to go with a "green" grease, there already some on the market.
Here is some other info the OP might find interesting:
New biodegradable grease meets demand for environmentally friendly products in engineering industry - WaterWorld
ELM
Environmentally Friendly Grease Based on Ricin Oil and Cellulose Derivatives
Eco-Safe - UltraLube lubricants
What You Should Know About Environmentally Friendly Lubricants