Surface finnish on castings?

[hightuned]

Cleaned the grime of engine and transmission cases and im wondering what i should use to get a nice surface finnish? Im not a expert on Porsche manifacturing techniques but the engine block (901.101.102.7R) looks like a pressasure cast and the transmission (915.303.101.0R) looks like its been sandcasted as the finnish is horrible?
Bead blasting would give me a nice finnish but im not to keen on the risk of glass residue. Is soda blasting a good idea, its just natrium as far as i know and should be solvable in water?

p.s its not my toothbrush, i borrowed i from my girlfriend.

[tom1394racing]

You can soda blast the case with Natrium. Just make sure that you thoroughly degrease the case before blasting as the soda mixed with oil can make a thick sludge that is difficult to flush from the oil passages.

After blasting I immerse the case in hot water and let it soak, then flush with hot water followed by a blowout with compressed air. The final step is to coat the surfaces with Gibbs to prevent corrosion.

[hightuned]

Thanks Tom
Is the the Gibbs coating like a heat resistent clear coat you spray on? Is this the right page All Purpose Lubricant & Penetrating Oil from Get Gibbs i cant find any coatings?

[tom1394racing]

Gibbs is a corrosion resistant spay/brush-on coating that will give the Magnesium case a deep grey oxidized appearance and will protect against corrosion.

[hightuned]

Thx agian

Tomorrow im of to buy the soda and give it a try.

[HawgRyder]

When cleaning engine blocks, I always used Tide with hot water.
I don't know why Tide is so good at de-greasing but it is.
Lots of different brushes and a big old washtub has been my choice.
Later...I built myself the biggest Ultra-Sonic cleaner anyone had ever seen...it was a monster...and with the correct fluid...got things spotless.
I can no longer buy the fluid anymore...seems that it is bad for the environment and peoples' health...LOL.
But I'm sure there is other stuff for sale now.
BTW...that tank was powered by more than 2KW of drivers...and the cleaning time was about 45 seconds.
Bob

[hightuned]

I gave that a thought as we have one at work for our 3d printer, but its to small for a engine case. Look for the soda used in cleaning up 3d printing its still avilible, ill check what we use at work?

[otto_kretschmer]

Originally Posted by hightuned

p.s its not my toothbrush, i borrowed i from my girlfriend.

well,

you better put it back before she notices its gone

[mikensam]

CRC makes a marine corrosion inhibitor that leaves an amber tint thats supposed to be similar to what the factory used(Chevron technol If i remember right).Sprays on,and leaves a dry/waxy finish.Definitly not a bling finish,but looks stock.Soda blasted a case and it helped clean it up and give a shiny finish,but after soaking in soapy warm water it greyed back up.Unless you want a bling finish,+1 for hogriders method.The CRC spray is $12 a can,plenty for engine/trans
Chris