What's the best blasting method?

[rickster1971]

Hi,

I've stripped my RD350 engine down and I need to clean up the outside of the crankcase halves so I can paint them and make them look nice before re-assembly. I will need them blasted to get rid of the old paint and aluminium "crust". Has anyone got any suggestions what is the best way to get these cleaned up? I've read that bead blasting can leave glass beads behind that can cause trouble later on. I can get my hands on some soda blasting kit, would that do the trick?

Also, how should I clean up the the seats where the bearings fit? Can I use something like Autosol to clean them up?

Many thanks,

Rick.

http://rd350nrebuild.wordpress.com/

[Airhead]

is there any aqua blasting done on Guernsey?

as for the bearing surfaces, yeah a quick rub with white spirit to remove the crud should do it, if theres anything left behind after that then autosol should shift it but watch for any oil passages getting plugged up with the stuff

[paul-666]

There are a few different ways to blast and different materials but for some strange reason I can't think of them Ill have to look it up for you but I'm sure they use some kind of nut to clean aluminium which leaves no traces behind, ill get Bach to you on this when I have refreshed my memory LOL

[paul-666]

Yes they can use wall nut shells or plastic beads instead of the normal shot which will leave less marks behind which is easter for you to paint over. HTH in some way

[paul-666]

Soda blasting works also on aluminum but I'm not sure on how good it would be at getting the crusty bits off . Have a look on YouTube there's a few clips on there about it

[Speedshop]

I'd mask off the bearing carriers and certainly not use any abrasive on them at all - not even autosol. If they are clean leave them alone.

We do use glass but masking off all the oilways is important I've got a set of small rubber bungs and blanks I use on my stuff. Glass gives a very open, coarse finish but is good at removing all the crud. You could finish with soda for a 'just cast' look, but you'll be there all week trying to get that paint off with it and if you are going to repaint it, the paint will adhere much better to the finish glass gives.

[rickster1971]

Thanks everyone for your input, you've all been most helpful.

I've found a place in Guernsey that does Aquablasting (thanks for the tip airhead). I'll pop down there tomorrow and see what they can do.

Speedshop, that's a good tip regarding the oil ways, I'll ask them to take care around them and to mask them off.

[Airhead]

Thanks everyone for your input, you've all been most helpful.

I've found a place in Guernsey that does Aquablasting (thanks for the tip airhead). I'll pop down there tomorrow and see what they can do.

Speedshop, that's a good tip regarding the oil ways, I'll ask them to take care around them and to mask them off.

OK they'll come up like new but they may ask you to remove the paint first...not easy nowadays because EU legislation has rendered paint strippers pretty useless...be prepared for them to ask you to do it though!

[drewpy]

aircraft stripper is the only effective paint stripper left. Its supposed to be for pro use only, but I'm sure with your tenacity you can get some.

I bought some POR strip from Frost restorations, which worked well too.

[rickster1971]

I've been down to the Aqua blasters and they use a fine grit/sand, not glass beads. Will this be OK? The firms main business is car body repair and they didn't come across as having done many bike crank cases. I'm a little concerned that I would never be able to get all of the grit out.

[drewpy]

no, don't use grit it may embed into the alloy.

can you post it to TSR vapour blasters in Southhampton?