email (option): horror@blueyonder.co.uk

I Built my own blasting cabinet from an old plastic barrel, its just enough to fit a 19" rim in there.
The blasting material was the most expensive thing on the build, and second to that the thingy to control pressure (20 €).

Never have gotten the hang of posting pictures on this forum but maybe some link here will work
https://www.flickr.com/photos/bohuslan/8271022616/in/album-72157629556474519/

%%bbCodeItem_1%%DSC02247 by Bohuslän i mitt hjärta, on Flickr

This picture was taken before the "gloves" where fitted.

And I always clean the parts before going in, and after taking them out.

/s

As Horror says if the gears are badly pitted they probably won't benefit from any kind of treatment...(other than a walk to the scrap bin)

If there is just light surface corrosion and no pitting, bead blasting with an aluminium oxide grit of about 60 grade will bring them up very nicely...

Some of the components in the picture with my previous post were cleaned using this method..

It won't affect them dimensionally and will have no effect on any heat treatment process carried out during manufacture...

I think it would be wise at this point to note that sand blasting, using sand, chilled iron or other coarse media is a wholly different process to bead blasting using aluminium oxide bead, glass bead etc. etc..

These compounds can be selected in grades that have no effect on components dimensionally and will not mark the surface finish or damage it in any way...
There is no need for example, to mask off threads or gasket faces on aluminium components..

All it does is clean the component..

When I worked at British Aerospace we had a blast cabinet set up to clean plastic components and even these weren't damaged by the process...(If I recall correctly it was crushed walnut shells that were used as blasting media)
..Ian

email (option): ian@wright52.plus.com

I use sand for rough and rusty steel parts, and sometimes for cast iron, mostly I try and use a pressure no higher than 4 kg (sorry for speaking metric), sometimes up to 5 but never higher because then the sand turns to dust.

For all alu-parts such as cases, timing covers and more I use soda glass (correct word in english?). I bought some very expensive material that can take over 6 kg pressure and that due to its fine nature it never damages the material, just leaves a smooth and clean surface. Mostly I use about 5 kg for the soda glass.
I have it separated so that half it is used on alu only. Reason for this is that if you use it on steel and then on alu you risk of shooting tiny bits of steel into the metal, and then you may get tiny spots or rust. Not good looking on your crank cases!

I started getting into this while restoring my Vespa (1966 180 Supersport) and found that it was quite possible to get real good results, without to much of an investment if I built my own cabinet (already had the compressor though). And as a bonus I have full control of the process (e.g. the no-steel use mentioned above).
But then I have no one to blame for the "Poor Quality Workmanship" when things go bad...

/s

That's a nice barn you Vikings got there.

And i thougt you were building a rocket !

I can think of at least one 'stove-enameler' round here who won't even clean grease out of the steering head - so when its heated it up, molten grease screws up an otherwise acceptable finish!
Then blames the customer .............. at least the guys i use tell me to go away and clean things out properly - or else they charge extra!

I guess its difficult for someone who does the odd restore - people like Ian/Ron and to a degree myself have been doing this stuff for years, and develop a network of specialist 'sub-contractors'.
I set up my own blasting cabinet etc, but like spray painting - the resulting dead-spray, dust, space, wasn't worth it.

I guess the answer is to clean VERY THOROUGHLY what you have and to use a specialist 'finisher' in the future - there are many small outfits around the UK who can properly aqua/soda/fine-grit/etc blast parts for you.

People tend to underestimate things like the amount of grease that can end up in a headstock.

On one of my bikes I warmed up the headstock with a blow lamp, just to get the grease out, what followed was a very long sausage of greases looped out from down inside the frame tubes.