M1000 track bike

[slob]

I asked what he used (in the end, it took a couple of days longer than expected because the paint on the heads was baked on and particularly stubborn, unlike the cases) he said "The stuff I usually use for carbs". The cases get vapour blasted all over. I expressed great concern about gasket and bearing surfaces but he assures me there's no dimensional change or metal removal. He does prep for Padgetts, Stan Stevens, Bob Farnham and even our old friend Paul Smart, so I guess he knows what he's doing.

[uksurfer]

looking good Rob, keeping you busy

will be good to see the finished result

[gary tompkins]

We need a 'like' button on this forum

I know the claims made for vapour blasting and understand the process - just not convinced. I am really concerned about the blast media being embedded in the metal or stuck in internal oilways - despite the claims that this doesn't happen.

I've got a diy blast cabinet from Machine Mart and it works quite well. If I can't clean a casting by boiling it then I do use glass for alloy and Al oxide for ferrous. Everyone agrees that this dry blasting shouldn't be used for engine internals because the embedded material cannot be washed off and will release when engine is in service.

The only exception to this is to use soda blasting and I've recently soda blasted some carburettors - inside and out. Although a bit slow, the finish is excellent and the advantage of soda is that it dissolves in water so part can be washed in warm water afterwards.

Vapour blasting claims to avoid the problem of embedded media but has anyone actually put a piece of metal under the microscope after vapour blasting to confirm that?

[slob]

I understand your point and could be undertaking a very expensive lesson for others! Who on the forum bought a USB microscope for their kids at Xmas and can I borrow it?
Do you use the Machine Mart kit with the soda? I was considering that but wasn't sure it would work properly with soda and my little compressor plus I'm starting to run out of space.

I meant to ask before... do you work at Perkins?

Rob, I've got a USB Microscope you can borrow to check it over - do you still work in Soho?

[jonzi]

Originally Posted by slob

... plus I'm starting to run out of space. ...

I have space in my garage if you want stick a bike or two in there.

I did work at Perkins for over 10 years but took early retirement. I've worked at a few big car firms but Perkins was the best firm I worked for although I am enjoying an easy life now and got plenty to do. I have got a nice little earner I run from home part time.

I don't think the soda would work with the blast cabinet as it would not suck up very well so I use a Machine Mart grit blast gun outside on a 'total loss' principle. It still does not suck up all that well but did clean the carbs ok which are 35 years old.
I've only used soda for the carburettors so far but it did waste a lot - I bought a big bag of soda from Ebay.

I'm not saying vapour blasting does leave embedded media but just asking the question? There is no real need to blast the inside - the burned oil stain isn't doing any harm.

[Kato]

This process is widely used by race teams and restorers and nobody has ever reported a problem with residual contamination.

The point of vapor blasting is it has advantages over normal blasting the water cushions the abrasive preventing it cutting the material being cleaned, therefore the surface is peened and washed at the same time giving a nice sheen to the finish that is far more resistant to marking than normal blasting.

A further development now being used if you are being that paranoid is dry ice blasting just as good a vapor and no containment media to worry about.

[utopia]

Originally Posted by zhango

..... I use an old Baby Burco boiler with hand washing powder for bare aluminium heads......

Now THAT is PROPER shed cool.
Do you do it on a monday ?

I'm now keeping my eyes open for an old Baby Burco.

It was my mum's and when I was a kid she did do the washing on a Monday!
You must be as old as me to know that!

Kato - yes I've seen vapour blasted heads and appreciate the peening effect. Do you know anyone who vapour blasts the inside of crankcases - I don't see the point looking at Slob's pics.

I hadn't heard of dry ice blasting - looks good.

[Kato]

Originally Posted by zhango

Kato - yes I've seen vapour blasted heads and appreciate the peening effect. Do you know anyone who vapour blasts the inside of crankcases - I don't see the point looking at Slob's pics.

I hadn't heard of dry ice blasting - looks good.

Agree it does seem pointless .......but I would still do it purely because I can, even though nobody else could see it, I would still know it was clean and sparkling on the inside

[slob]

James, yes I still work in Soho, if I can borrow the microsocope for a couple of days when the cases come back we might be able to put zhango's mind (and mine) at rest. I'll give you a shout.

No worries, I can drop it by on my way home from work - just drop me a line when you need it.