Topic: Media blasting fork lowers and top tree... QUESTIONS!!

[Elniniomuchachos]

I was going to polish my fork lowers, but I don't really want my bike to be all super shiney,and whatnot. (plus it takes forever to do so, if you don't have the right equipment.) So...I am thinking about having my fork lowers and top tree media blasted. I have a few questions about leaving them with the dull aluminum finish.

1. Can I leave it the dull aluminum finish?
2. IF so, will they need a protective layer, (clear coat, whatever)?
3. What would happen if I left them without a protective layer?
4. Has anyone doen this, (to see examples)?


thanks for any help, or suggestions.

[unitedguitar]

I have seen a few people do things like this with aluminum parts. It gives it kind of a machined look. You won't technically have to do any kind of coating on it but I would definitely recommend using a flat or satin clear coat as the raw aluminum will eventually oxidize.  It should look similar to all of the satin finished stuff the that Russell Mitchell does over at Exile Cycles.



Hope this helps.

[MoMo]

I glass beaded the triple trees on one of my CB400 fours, I like the look.  Bike is sitting in my garage without any protective coating and still looks the same as when I did it six months ago. Nice look for a cafe style bike...Larry

[RickB]

I had all my aluminum parts hydro blasted. Engine casings, carbs, master cylinder, hubs and fork lowers. You can see the results of here:

http://forums.sohc4.net/index.php?topic=51957.msg791388#msg791388

It basically takes the aluminum back to straight-out-of-the-mold new. It's dull but bright too. Just not shiny and reflective. I was concerned about not coating it all in something. I've heard horror stories about it oxidizing in a matter of months. I decided to leave the engine casings uncoated and after almost a year, they look as new still. Just give it a rub with wd-40 or some other oil every now and then.

The fork lowers I took to a metal polisher and had him give them that directional brushed aluminum look as that's how they were from the factory (plus I agree, I don't like the mirror finish polished look). I then had them clear coated by a mag wheel place as I was told by the polisher that by brushing them, you were opening up all the pores of the metal making it much more susceptible to oxidation.

However with the clear coating I'm now worried they will yellow after a while. I was told by the mag wheel place that this wouldn't happen because of the quality paint used, but I don't trust them. My thinking is, if they yellow, I can just get them hydroblasted again.

Here they are polished to a brushed aluminum look and clear coated:

http://forums.sohc4.net/index.php?topic=51957.msg834381#msg834381

In fact, it's so worth getting everything you can hydroblasted if going for a nice ground-up restoration. It's cheap compared to the amount of scrubbing and sanding and polishing for half the quality of the result. There's nothing better than getting fresh clean parts back from the blaster or electroplater!

As a side note, I have a spare set of 1975 CB400F fork lowers freshly hrydroblasted. I've been holding onto them for no good reason, so if you or anyone else wants them, contact me with an offer.

Rick.

[Elniniomuchachos]

Man, those parts look nice. I'll have to look into that hydroblasting.