Vapour blasting - wow, just wow!

[Hoopy_Frood]

I didn't take a before picture as I wasn't expecting to post any shots, but the cleaning came up so well, that I wanted to show it off!!!
These are the heads from a DJ engine I bought from SynchroPatrick of these lands - the engine is in great condition, all the studs are perfect and I am doing a full rebuild on it at the moment. I put the heads in to get cleaned and am simply over the moon with the results.









I have found small cracks between both sets of valve seats in each head - they're smaller than 0.5mm wide though, so I think they'll be ok to use again.

[JamesKT25]

Stunning Results! Is it an expensive option? My uncle has a blasting cabinet is it much different to sand blasting in terms of process?

[Hoopy_Frood]

It was £70 for both heads, which isn't massively cheap, but the finish justifies the cost (to me anyway). I could have spent a huge amount of time cleaning it by hand for a finish nowhere near as good.

I'm not an expert, but I think bead blasting can leave particulate matter on the metal, which can then find it's way into the combustion chamber causing all sorts of headaches. Vapour blasting leaves less of a residue (I think), so it reduces the risk of ruining the engine.

My next steps are to have new exhaust valve guides fitted to the heads. Then I want to split the case & clean it up, take the crankshaft to get measured and reground if needed. I fear that I have damaged one of the pistons during removal though. Can these be bought individually does anyone know?

[CJH]

They certainly do look good. I'm at the beginning of a 2.1 strip and rebuild and have been thinking about how to give everything a good clean. I saw this thread about using baking soda on carburettor parts (maybe you have to use bicarbonate of soda if you've got twin carbs? - I'll get my coat). The theory is it's not too harsh, and any residue can be dissolved and washed away with water. I've got a cheap Lidl blasting kit so that's what I'm planning on my engine bits. Once I get this stubborn head off that is.

I can't imagine it getting such a good finish as yours though.

[sciroccotune]

The look very clean! I haven't done any air cooled engines but I would be worried if the mating faces looked as pitted as the 3rd picture? Could be different on an air cooled?

[pionte]

very impressive results.

As sciroccotune says the surface does look pitted, are you planning to have them skimmed ?


I hate working with anything that is dirty so your link CJH was very cool...

[123-jn]

Pitted yes but not as bad as many, just a bit of JB weld and a sand down and hey presto!! one of mine was worse than that.

[itchyfeet]

They do look good but dirt is only a problem in a small number of places so is really a visual thing not really going to improve performance, its also not going to stay like that for long, i cleaned my engine now i have aluminium oxide which is eating my metal, thinking of coating it in some dirty oil to protect it

is it me or has that exposed cracks between the valves and a big hole by a valve seat?

[ghost123uk]

using baking soda on carburettor parts (maybe you have to use bicarbonate of soda if you've got twin carbs? )

Well I thought it was funny

[AdrianC]

using baking soda on carburettor parts (maybe you have to use bicarbonate of soda if you've got twin carbs? )

Well I thought it was funny

Round of applause from here, too.

[CJH]

using baking soda on carburettor parts (maybe you have to use bicarbonate of soda if you've got twin carbs? )

Well I thought it was funny

Round of applause from here, too.

.....pokes head out from behind stage curtain.....decides not to give up day job after all.....

[Ian and Lins]

Stunning Results! Is it an expensive option? My uncle has a blasting cabinet is it much different to sand blasting in terms of process?

Definitely NOT a good idea. Sandblasting will get into all sorts of galleries, nooks and crannies and will make a wonderful grinding paste which could quite easily ruin every moving part of the engine. 'Careful' masking off will NOT work.

[JamesKT25]

Not going to sand blast my engine dont worry i was just intrigued by the difference in process, can i use the sand blasting cabinet and kit but use soda as the medium??

[AdrianC]

This gives a quick overview of vapour blasting...
http://www.goodwoodvapourblasting.co.uk/how-it-works/" onclick="window.open(this.href);return false;

So it's basically media blasting, but using a water jet rather than an air jet - still with an abrasive, although the water takes some of the "harshness" out of it.

The second half of that page - ultrasonic cleaning - sounds interesting, though. Given how cheap little ultrasonic cleaners are, intended for jewellery and the link, I wonder if something could be molished, perhaps using something like a normal MachineMart cleaning tank as the basis...? Hmmm... I guess the fun'n'games would come in finding an ultrasonic cleaner that could cope with the degreaser/solvents...

<scratches head, ponders>

[faggie]

yes you can use bicarbonate of soda in a blastic cabinet but unless you have a big compressor you wont have enough pressure and you will be at it for absolutely hours I also prefer glass bead as its loads quicker but can only be used if everything is stripped down and walnut shells are good but expensive