J S W

I am having an engine of mine cleaned up and re built, I know a guy who does shot blasting but it sounds very abrasive, in his words people say when he blasts metal it looks like he has undercoated them as it leaves a matt finish ready for buffing. I am just a bit concerned that this may to too strong for an engine.

I have heard previously that bead blasting is ok for engines?


Anyone on SN know about Blasting?

Cheers

James

Pumpkin

Shotblasting is usually grit or sand. Its good for exterior panels etc but can dent and distort fragile aluminium panels.

Bead blasting uses a fine glass bead media. Generally its ok for engines, but beware of beadblasting bearing surfaces and anything must be very very carefully flushed out as any bead left inside will cause rapid wear of bearings etc.,

Big C

It depends on what you want to do with the surface afterwards. A combination of the type of metal, media used and the pressure will all be contributing factors to your desired finish/prep standard. Without knowing what you intend to do, it is difficult to advise.

If you are going to re-protect or remove corrosion, sandblasting is usually best. If you need to toughen up the metal itself, shotblasting is usually best. If you want to remove old finish (paint, laquer etc) then plastic media (bead) blasting would normally be best. There are many other types of blasting available (cryogenic, water etc), and many different types of media.

I used to be a blaster you see (ah///takes me back that does¬!).

Hope this helps.

C

CrisPDuk

If it's an Iron block get it shot blasted, but make sure you prime & paint it VERY soon after as the surface area after blasting is massive & very prone to corrosion.

If it's ally beadblast it , but make sure they only use a light pressure as blasting tends to stress relieve castings & ally can twist. Not good if it's a block or a head.

To be honest I would only use either method on a motor as a very last resort, if you've got it stripped to the bare components soak it in parafin or similar as it will get rid of the grease, then wire brush any rust, it may take longer but it is far kinder to the components. Plus as pumpkin says, the slightest bit of grit left in a gallery somewhere will reduce your engine life to almost zero

J S W

It is an alloy engine and will be polished and laqured (sp?) hopefully to a shiny finish and will be displayed in my lounge.

I have been to see a guy locally who has been recommended to me but I think the V10 may be to big for the blast cabinet which is a problem.

James

Pumpkin

The beadblaster I'm using is very gentle - you can blast the back of your hand... Works very well - and I'm very careful to flush out the parts afterwards.

An alternative is a decarbonising fluid that you leave things in overnight. Again you've got to flush things out very well indeed.