FullGas

HF is seriously nasty.

I'd never use anything that contained it.

canklecat

I use 91% isopropyl alcohol once in awhile between more thorough cleanups on the brake pads and rims. Just a cotton swab or rag, nothing fancy.

NOT rubbing alcohol, which may have oil to ease massaging the skin. Usually this is in a green or other colored plastic container. The plain alcohol is usually in a white translucent bottle in the US.

When I wash the bike properly I'll use an old sponge that has that sorta-scotchbrite type scuffy pad on one side. Usually it's pretty worn by the time it's retired from house cleaning, so I'm not worried about damaging the aluminum rim or paint.

gsa103

Don't use steel wool. It will embed fine steel particles in the rims which will then rust. Scotchbrite and isopropanol work just fine. The only reason to use something stronger is a particularly bad tar stain.

coominya

Yes you are absolutely right. In high concentrations HF is deadly, in the stuff I buy, which is sold to the average joe, it's very dilute, but if you don't feel confident around chemicals you should definitely steer clear of it. A lot of people in our modern world only have urban living skills and should keep away from things they have no experience with. The shops that sell that chemical should really restrict it's sale.

Sy Reene

Seen a few plugs for scotchbrite, and concerns over steel wool. I think someone though should qualify what version of ScotchBrite they're referring to. A quick Wiki lookup of scotchbrite indicates that at least (some?) of their products are abrasive due to inclusion of Aluminum Oxides.. able to scratch glass. I think Scotchbrite pads of some variety have been recommended for buffing scratches out of titanium, etc. For me, I find the non-scratch blue sponge Scotchbrite pads generally sufficient for cleaning purposes (made for nonstick cookware).

sch

HF in any concentration is extremely hazardous, being one of the relatively few substances
that go right through the skin on contact. Even low concentration (like the under 10% in
Ali Brite) HF can cause serious injury, especially since there are few initial symptoms,
they only appear after a few hours. This stuff, even though sold for industrial use,
should be on a restricted access only. HF = hydrofluoric acid HF gas is released by
the aqueous solution and is equally toxic.

Kitchen grade scothbrite pads should be fine for bike rims and readily available any
grocery store. Even these are a bit abrasive and will produce faint scratches on
highly polished aluminum, but those kind of rims are uncommon these days.

FullGas

I've used reagent-grade HF in a laboratory setting, know full well what the hazards are.

to simply clean a bike part, there's no reason whatsoever to use that chemical, regardless of concentration.

coominya

Well you're entitled to your opinion of course but not everyone shares it. Perhaps your opinion is biased by your work in the lab with full concentrate, have you ever used the retail grade cleaners that contain it?

Down here we use the chemical to clean boats, bull-bars, all manner of aluminium parts. using it, under controlled conditions, to clean the bare rims of a bicycle is no different. Like I said, if you don't feel confident around it, don't use it, but how can you make a blanket statement no one else should, when it's in common use and sold across the counter at hardware stores? I simply wont accept that, not after 30 years or experience with the product.

coominya

No one is disputing any of that, but it's sold across the counter, just like guns are, like salt is. Both of which are equally dangerous if not used with wisdom.

But Perhaps we have a different mindset down in Australia, we handle these chemicals all the time but I realize in north america things are different, so I will say this.

No one on this forum should follow my opinion and use this or any other toxic chemical in the maintenance or refurbishment of a bicycle. We want to keep people on the forum safe and there are plenty of other methods to clean aluminium parts, as described above.


Be safe!
KEEP AWAY FROM ANY PRODUCT THAT CONTAINS ACID.

cyccommute 

This may be one of those English/American translation things. The Oxford English Dictionary says

eMC, which seems to be a British pharmaceutical manual, says surgical spirits BP is

eHow says that it is mixture like the eMC says but with some other ingredients. eHow also says

In other words, it's used like rubbing alcohol (aka isopropyl alcohol or 2-propanol or 2-propyl alcohol) but it isn't the same chemical. Methylated spirits is ethanol (drinking alcohol) that has been "denatured" by adding methanol to make it poisonous. There are lots (40 to 50) ways to "denature" alcohol. Lately the method used adds a foul tasting chemical rather than make it into a poison.

By the way, mineral spirits (or white spirits) is probably an improvement over the mixture for surgical spirits above. The castor oil will definitely leave behind a residue. The methyl salicylate is oil of wintergreen and is added to make it smell nice.

FullGas

would never use such a product. no need to when there's a variety of vastly less hazardous options to choose from.

napalm is probably effective for killing gnats, but wouldn't use that either.

cyccommute 

I don't think anyone calls "denatured alcohol" isopropyl alcohol. The point of the "denaturing" is to render the ethanol undrinkable. Most people wouldn't drink isopropyl alcohol in the first place so there's no need to adulterate it so that people won't drink it.

I'm a chemist with 35+ years of experience. I have yet...and probably never will...to work with hydrofluoric acid. I know the hazards and I know how to protect myself against them but, honestly, HF is just plain too dangerous to use...even for a trained professional. Your aluminum cleaner contains 1% HF and 4% sulfuric acid which makes it very corrosive.

But the real problem is the HF. Hydrofluoric acid is easily absorbed through the skin but it is a weak acid which doesn't give much outward appearance of chemical burns. Basically, you just don't feel it on the skin until it has had time to do a lot of damage.

HF's other danger is that it is a calcium scavenger. It will pluck calcium from your skeletal structure but, more importantly, it will pull calcium from your blood stream. Your body needs that calcium to regulate heart rhythm. If you tie up enough calcium, your heart beat becomes irregular or the heart even stops. It doesn't take too much skin coverage (160 cm square or about 25 square inches) of exposure is enough to be deadly. It is also easily absorbed through the mucus membranes and it doesn't have an odor at exposures low enough to cause serious problems.

Trust me and Full Gas, this is dangerous stuff to use even for people who are trained in using it.

rekmeyata

I would first clean the rim with Acetone to remove any gunk, then if there are light scratches or light grooves on the rim hit the rim with 100 grit sandpaper by following the grain of the aluminium rim which won't be up and down, then follow up with a 400 grit sandpaper, and finally finish off the rim with red Scotch Brite pads. If there are no scratches or grooves then just use the 400 grit then onto the red Scotch Brite.

Once your done with all of that remove your brake pads and examine them closely, if they are glazed rub the pads on a 100 grit sandpaper to remove the glaze, then pick out any stuck foreign particles out of the pad with a fine pointed tool. The order of picking and sanding isn't important.

coominya

Thanks for the added information and the concern, I'm surprised the shops are allowed to sell it to untrained people. I wonder what other dangerous substances are lurking in household solutions.

kcblair

While we're on the subject, how about highly polished aluminum rims ? Steel wool or sandpaper , surely will scratch the surface. I'm thinking citrus degreaser followed by IPA.

rekmeyata

Not if use fine grit...of course it does depend on if the rims have scratches that will be needing fine grit sandpaper to fix it. Also don't forget, highly polished rims are a product of multiple polishing agents that go from a course grit all the way to a super fine grit that does all the polishing.

I wouldn't use steel wool either, but I would use red Scotch Brite pads.

Back in the day when all rims were pinned together, the seam left an edge that the factory would not sand down well enough which resulted in the brake pad grabbing at the seam, so we sanded our rims to smooth out the seam to prevent the grabbing, and after a few stops the brake pads would remove the shiny area that was a result of the sanding. So a mirrored polished bike rim will not last as a mirror polish for too long, plus in addition to that a mirror polished rim will not stop in the rain as well as a rim that does not have a mirror polish to it, this is why you never want to go finer than a 400 grit sandpaper on a rim so that the rim still has minute roughness to it so it will stop better in the rain.

rodscot

I bought some plastic pot scourers. Similar to Scotchbrite pads [couldn't find those in the store]. They worked fine on my rims.

79pmooney

accidental post

79pmooney

But be aware that there are many people who get strong reactions to acetone. Usually the result of having worked with it and other chemicals. I got to be known at my workplace as the canary because I could feel my skin crawl from solvents I was toxic to before I or anyone else could smell them. Since they made work impossible for me, I would search until I found the offender. I always did. (Open containers, paints, once an old air freshener that contained acetone.)

I worked with fiberglass until my reactions got to the point where the acetone in the air in the shop would set off my reaction when I walked in Monday morning. I lived with the fiberglass skin crawl all week, not from the fiberglass but triggered by the acetone. The itch lasted all weekend. Monday morning I would wake up, my skin feeling good finally.

I get my hair cut at Supercuts, a place that uses little of the solvents common in beauty parlors. Many of the women who have cut my hair work at Supercuts because they can no longer work in the salons (and would probably have a reaction from your acetone).

Ben

kcblair

Thanks, Scotch Brite pads sounds good. I picked up a set of 90'ish Campy aereo rims, that have black marks
from pads. The braking surface is in good shape and shiny.