Our team is doing some off season overhaul of our competition bot that has been through the mill with normal competitions, lots of practice driving, outdoor street demo, WPI BC, … Anyway we pretty much neglected the proper care of our 6WD #25 chain drive. We have done some soaking to clean out some of the grime from the chains. The question is what we should use for a lubricant and how often to lubricate? TIA
I would avoid soaking chains in solvent. It leaches out the lubrication in the pivots where it is difficult to get back into. One way would be to soak it in a hot light weight gear oil then wipe off the excess. Probably a little overboard. You can clean them with a rag lightly soaked in cleaner. Then lube them with a chain lubricant meant for bicycle chain. Wipe off the excess. For chains exposed to dirt & grunge, an argument can be made for little to no lubricant. Or lube often with something like WD40, wiping off the excess. You are mostly lubing the side plates.
I recommend a motorcycle chain lubricant, probably one with molybdenum disulfide in it, such as ‘PJ1’. They’re designed to stick to high-speed chains where light gear oil won’t.
Also, like the previous poster, I don’t support ever soaking a chain in solvent to clean it. You’ll never be able to get the lube back to the crevices where it was.
Finally, I’ve not had good experience with #25 chain. Go to #35 if you can. Also, WD40 is okay for a while, but it evaporates. In a month, it won’t be there.
As for how often, if you can touch the chain and not get dirty, you probably need to lube again. I lube my motorcycle chain every third day.–200 miles. Oftener is more better.
Lack of regular lubrication is one of the most common causes of trouble for many FRC teams. Anything that can make it faster and easier to do makes it more likely to get done. We keep a small paint brush in a ziplock bag with our lube supplies. It is great for re-coating drivetrain chains with a light coat of chain oil. While running the drive very slowly, hold the oily brush (not dripping, just moist) on the chain in a stationary spot (in an open span away from sprockets and pinch points) and you can lightly and evenly lube the chain in just seconds.
We use DuPont Chain Saver. It seems to soak in well, and it dries, so there’s not sticky grease or oil for dirt or contaminates to stick to. How often to re-lubricate depends heavily on how much use the chain sees. During competition we would re-lube our drive chains 1-2x a day.
http://i.walmartimages.com/i/p/00/03/61/21/19/0003612119183_500X500.jpg
FWIW 95 has had fine luck with 25 series chain, we even used it in our drive-train last year. It is perfectly reliable when implemented properly.
Just out of curiosity, what issues have people seen from not lubricating chain? I don’t think my team has ever lubricated any of our chains, and we still have our robot from Breakaway (2010) driving around as a practice bot on a regular basis, with the original drive train intact (The drive train and frame are the only parts of that robot that are original… everything else has been replaced for various prototyping/training purposes).
When you buy chain, it’s already heavily lubricated, but mostly with a heavier grease-type lube. I’m pretty sure an over-designed (too big, like #35) chain would last for hundreds of hours without ever lubricating it.
But is hundreds of hours enough? And the other thing is, the minute someone decides to clean the chain by soaking it, all bets are off. Chains like to be dirty.
There are literally hundreds of teams who run 25 chain in their drivetrain with no issues. #35 is overkill for almost all FRC drivetrains, but it has its place in high reduction arms and such.
Simply put - efficiency. When it gets really bad there can be all sorts of issues including: overheating motors, drivetrains that pull to one side excessively, dramatic power loss, and loosening chains.
Lubricating the chains on our 2012 robot’s shooter bumped our range up by 20% or so.
If you go with this option often could be close to daily with heavy use. While the exact composition of WD40 is a company secret, it is roughly a mix of mineral spirits & light machine oil. The oil part is persistent as any oil. The solvent helps to penetrate the side plates.
Anything with molybdenum disulfide is going to be messy. One reason why I ride a shaft drive BMW rather than one of the excellent Japanese bikes.
Or for lower resource/teams who do not hold tolerances on spacers in the drivetrain. #35 chain is extremely forgiving, in all my years in FRC I’ve only built one robot without #35 chain in the drive. It may be old school, but its nice to never have to think about it.
We use Dupont Teflon® Lubricant to keep all our chains and gearboxes properly lubricated.
http://www.mobiloil.com/USA-English/MotorOil/Other_Products/Mobil_1_Synthetic_Grease.aspx
This stuff right here. YEAH BUDDY.
That grease is excellent! What NLGI number do you recommend?
For grease like that, I would probably say #0 or #00 for chains, But I haven’t personally run it, so im not sure.
Only downside to using grease on chains is that it can get flung off at speed, and it doesn’t really penetrate the side plates unless its thin.
I have run #1 or #2 in gearboxes, but that’s a bit thick for chains.
Or for the lowest resource teams, stick with the Kitbot belts, no lubrication, no maintenance, battle tested, simple, comes with instructions and all the parts you need in the kit. If your resources are that low, your time is better spent on things to play the game with.
Thanks for all the good advice. CD to the rescue.
We have had excellent results with #25 chain by carefully aligning the sprockets and tensioning the chain. The only time we threw a chain was when part of the field fell onto the carpet and our guys drove over it and the metal bracket lodged in the chain derailing it. #35 chain drive system weighs more and is larger volume, overkill IMHO.
As for the soaking, I think we just soaked in a light oil at room temperature, not a true solvent. There was a lot of grime that came off the chain just the same.
As for choosing #25 vs belts: Belts seem to take up lots of volume and I am worried about proper tensioning. Chain length can be easily modified, nothing to order and wait as with belts. Changing out a belt requires a lot more robot disassembly than changing out a chain by removing the master link or popping a pin. The price is right. The chain system may weigh more but the wgt is down low. Belts, however, are quiet.
As for the lubricant now that I think about it, I am sure I got some motorcycle chain lubricant lying around which should be mighty fine for the bot.
Again thanks for the advice. It helped a lot.
If you want to soak the chain in something to clean it, then try using DRY BICYCLE LUBE…then for typical maintenance lubrication use the wet lube and wipe off the excess. I disagree with the comment “chains like to be dirty…” it is the dirt that eventually kills a chain. A good lubricant will keep the chain clean, which is good for both the life and performance of the chain, and for your members’ hands when they are working on it.
Some of the commenters say they are using a solution containing water (yikes!) and degreaser (yikes!) in this product.
What cleaning solution do you use in this product?
I think you could run water and degreaser through it, then regrease the chain with the same machine.
That product is for mountain bike chains. Chains that live in a nasty environment, mud, water, & sand. It cleans the side plates & rollers. Typically a surfactant like simple green & water. You move the chain through it, no soaking. Being cheap, I just use a rag soaked in cleaner to the same effect. I have yet to see a FRC robot chain that dirty. Maybe for next years water & mud game?
Head to local bicycle shop and pick their brains. I mountain bike for years and used both the park an the Pedro’s machines dry. I used to use dry lubes on my chain to avoid dust and such from sticking. Personally if the chain was that bad I just replaced it, usually once a year sometimes twice.