I like the finish in the attached photo - green engine with alloy housings.
What is the best way to get the good clean alloy finish with a bit of gloss on the gearbox?
I was going to bead blast the housings and give a coat of clear enamel.
Any other options? eg soda-blast??

I had mine hydoblasted. Abrasive blasting makes the aluminium porous and will trap dirt again pretty quickly. Hydroblasting uses high pressure water to clean and renew the aluminium surface. It also seals smoothes the surface and makes it less porous. I also had the gears in the box hydroblasted and they look like new. It cost me $80 and it looks new.
If you are in Melbourne I can recommend a good guy.





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I recommend paint stripper and a wire brush for the aluminum bits. The paint doesn't stick well at the best of times, so it strips easily.

Also, I find that blasting can open up the pores in the aluminum and make it get dirty quicker.

If you look at the last page of my build log, you can see I have the same effect on my 1098.

viewtopic.php?f=3&t=83263&start=45

I plan to leave the parts bare, I don't think a coating is necessary, modern engines have lots of raw aluminum, but the grade may be different to these old parts, time will tell

Associated grit blasters do hydroblasting with water in Adelaide (in Edwardstown behind Castle Plaza).
The owner recently showed me a couple of alloy motorcycle gearboxes that he'd done and they looked fantastic (just like the parts in your photo).

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Your imagination is only limited by the size of your wallet
"61 850 original and crusty (Mavis)
"64 Smooth Roof Van (Colin)
"67 Deluxe resto project (Monty)

A lot easier than a one haired toothbrush and some Jif. It may cost a couple of bucks to get it done, but well worth it.

Hydroblasting all the way! It's a rather benign process, too. I left an oil seal in a crankcase once, and the rubber was undamaged, albeit spotless at the end.

Makes motorcycle motors look brand new as well

Is there any need for a coat of clear after the hydroblast, or do they stay relatively clean (assuming no oil leaks).

No real need, it's just like it was when new. Just don't use caustic type cleaner on it.

Not at all. The chap I use in Melbourne is also an engine builder. And he's adamant that after blasting the parts are as clean as they'll ever get and ready to go back together.

you could use some of this stuff, not cheap mind you. No idea on how long it would last.
http://ultraeverdryonline.com.au/

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Nick

http://www.ausmini.com/forums/viewtopic.php?f=3&t=86675

Hydroblasting is a process invented by Rolls Royce to clean their jet engines.The process is performed inside a cabinet, of dimensions mostly approximately a metre cube. It is a low pressure system (around 25psi)of water pressure with about 20% of the volume made up usually of glass bead. then to make it clean/agitate ,air is added to activate the cleaning. It is not abrasive as such, because it removes microns of material only, and struggles to remove paint, silicone because it is so soft, or powder coat. It is primarily for non ferrous materials, alloys, magnesium, brass, even plastics or circuit boards can be cleaned, as the air pressure can be dropped. Alloys come up like brand new on most occasions, but like today I did a rusty mini crankshaft and camshafts and they come up like brand new, except it does not obviously repair pitting. Oxidised filthy black mini gearbox cases come up like brand new, SU carbs and Webers the same. If parts are not going to be painted then a "peening" is done to the surface to make it resistant to future grime and oxidising. There are hydroblasters all over the country , and most do a very similar job.
As a past owner of Link Automotive and Minisplus I believe I am well qualified to comment on this process for minis, it is an excellent process, but bear in mind we are cleaning with a very fine glass bead, so only items that are stripped down to bare essentials etc should be done, steel if fine, but it is raw metal, and whilst I put a rust treatment on ,that cannot last forever. I do a lot of gears, and the cleaning of the synchro surface especially appears to be beneficial to them working well, and any flaws in the part become obvious. Some items should not be done, e.g., items that I refused today were a water pump, and breather that the mesh could not come out of to clean. As it does not remove paint, most mini gearboxes I get have to go in a paint stripper first.\, and most hydroblasters prefer parts to be cleaned of oil first. On my own cooper S restoration I did most of the rubber products that I wished to reuse, and generally it works very well on rubber, without harming it
Cheers Lindsay Siebler Hydroblast Plus Melbourne

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1967 EX works rally mini restoration virtually complete OBL45F
1965 Mk1 Cooper S
1970 Colt 1100F SS
2014 Mitsubishi Imiev fully electric daily driver
1948 Allard M coupe Olds 215 v8 project
1971 Twin cam Escort ex Uk championship winning rally car project

Thanks for all the comments, especially the explanation from Lindsay.
Thanks Andrew9 for the link - good effort on your panel work.

Any recommendations for a Brisbane based hydroblaster?


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Simonw
Brisbane QLD
1st car - 1964 Mini Panelvan 850
Previous - 1978 Leyland LS 1275 Gold
- 1969 Mini K

specialised blasting services
they were in capalaba but have moved
i used them quite regularly for exactly this

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.