Greases and Lubricants

Hi everybody,

This year we are planning on using linear slides on our robot and I’ve noticed that a lot of teams lubricate them to reduce friction, so I have a few questions.

First of all, does lubricating axles change performance since delrin has a low friction coefficient ?

Second of all, I saw that most teams use white lithium grease. The problem is that our robot generally stays in my room so my question is : does lithium grease smell bad ? Because if it does, I don’t want to spend my whole life with the smell of it in my room. If it does, then is it possible to use vaseline (pure petroleum jelly) as a lubricant ?

And finally, how often do you lubricate your linear slides ? Do you just put the grease on once and leave it there ?

Thanks

We lubricated our slides with normal machine oil, and it makes a huge difference. Just make sure it doesn’t build up and get dirty over time, so wipe them down and re-grease the slides every so often.

Cool thanks ! But it smells doesn’t it ?

We used this stuff because it was the only oil I had in my basement, and it turns out it really good for the slides:
http://www.homedepot.ca/product/3-in-one-electric-motor-oil/948650

I don’t think it really smells, maybe a very tiny bit. But it is quite oily, so it is a but messy when dirt sticks in it, and also stains. After worlds my team shirt had quite a few oil stains on it. I guess that’s what happens if you’re the only one who builds and maintains the robot.

We used white lithium grease from Home Depot and it is amazing. It doesn’t smell too bad and your slides become almost completely frictionless if you apply it correctly.

Cool thanks everyone ! I think we’ll go with the white lithium grease, don’t want oil stains all over my room.

@snowpenguin, what do you mean by “apply correctly” ? Is there a wrong way to do it ?

i used to use spray on industrial silicone lubricant
you spray it on, its more like an alchohol rub than oil, and it evaporates quickly.
However, after drying it leaves a lubricative film on the slides, does the job well.

Unless it gets dirty after drying it doesnt smell or stain.

Is that aerosol based? Grease can only be non-aerosol based to be legal.

@botfather, we find if you put not enough or way too much grease it can cause some strange issues… Best practice we have found is to apply grease to a clean paper towel and rub it in on both surfaces to be sliding. You’re looking for a thinnish layer of the stuff.

Are all lubricants classified as grease?
If so then what I have been doing is illegal, I did check with the inspector though…so idk.

Yes it is aerosol based, however I don’t think it’s grease, its just a liquid lubricant.

The manual says “any non-aerosol based grease or lubricating compound, when used in extreme moderation”

The moderation is sometimes the hard part. The tube of grease on the paper towel can be gloppy. So wipe it along as best you can so no residue drips off.

Does anyone know what the reasoning is behind not allowing aerosol-based lubricants?

I hear aerosol and I think of flammable but I doubt it is that. Probably they don’t want a student with breathing problems to be hurt because of no experience or precautions. May also be students at competitions reapplying grease that is the reason.

I am guessing because of dripping lubricant staining the field mats or the carpet at the school where you run the event?

Yup… sprayed lubricant has a pattern that is tough to control. Aside from the field tiles, the rule is meant to protect other items explained in the Rule .

The rules state: