Bead-blasting

[Andrew H.]

Anyone had any experience bead-blasting gear cogs? Would bead-blasting damage the hardening on the teeth? Ours are a bit rusty, and a rotating wire-brush doesn't properly access all the nooks and crannies.

[Brett Nicholls]

Hi Andrew,
You could try Soda blasting which is much gentler. Another alternative is to use Molasis which you can get in bulk from the produce store. You then mix with water - I use 1 part molasis and 2 parts water. Leave the item to sit in the mix for about a week. Parts will be back to bare metal and you can just rinse under water. The solution will turn some sufaces a blackish colour - but they will be free of the rust. Hope this is of help.

Regards,

[Lynn Eades]

I do not believe bead blasting would do any harm what so ever to your gears. You are talking glass beads, I assume. The stuff is however, harmful to your lungs, if you don't take the pecautions required. It is also very important that your clean up of your parts (to have them 110% clear of any glass residue) is vitally important.
Glass bead blasting can make a component more durable because it tends to eliminate stress points from which fractures start.

[chris vickery]

Bead blasting absolutely. A friend of mine rebuilds truck transmissions and uses this on gears, especially if they are hard to find or obsolete.

[Andrew H.]

Thanks for that. Re molasses, I am a convert and have had great results with it. I have already used it on the gear cogs and now I want to get rid of the black residue and also some persistent hard-caked grease that is reluctant to dissolve in solvent.

[lynx42]

I use molasses quite a lot and this is the result, lovely shiny clean bits.

Lynda Griffith082013 034.jpg

I use a mixture of 10 to 1 molasses to water, that is diluted enough.

I wire brush each item after rinsing it off and then it is ready for priming after a wipe over with a wax and grease remover.

Lynx manual carrier before immersion.

Lynda Griffith082013 021.jpg


The finished item ready for painting after repairing it.

Lynda Griffith082013 022.jpg

DO not put any die-cast items into the solution or you will end up with that a bit of mush.

Any oil or grease will stop the process at that particular point, but will continue to work on the rest of the item.

Regards Rick