Best media to use for Media Blasting an engine

[tkarvelis]

I am in the process of rebuilding a DI. I have all the parts back, and I started scrubbing down the crank case. I found some areas where the paint has lifted, and oxidation formed under it. I would like to take it to be media blasted

I stopped in a shop near me, and talked to them, and they asked what I wanted it blasted with. I did not know, so he gave me a ballpark price of $100. He offered to powder-coat it also...

What would the best way to blast this? Currently the engine is apart, and cylinders were sent to a machine shop, and bored for pistons. I have received them back, and i am concerned about media getting into the small areas.

I should have had it blasted before, but....

So....

What media would you use for spot blasting?

Should I re-assemble for the shop to blast? It will be bolted together without gaskets...

Worry about the contamination of the cylinders?

 

[Sportster-2001-951C-Stock]

Soda blasting would probably be my 1st choice.

 

[GulfCoastJets]

I think at a minimum one of the more important considerations is what type of material are the parts made of.

You don't want to induce corrosion or stress by using a process where dissimilar metals will react such as aluminum vs steel.

From there its equally important that your objective is known -

- just paint stripping
- paint stripping and corrosion removal,
- light to moderate surface etching for plating (anodized, cadmium, etc.)

if you explain this to the shop, which you may have done already, I am sure they should be able to correctly apply (uncontaminated media) to your parts based on what they have in stock.

Also find out how each option will affect you price wise as that could also be a factor in determination. If they have to get some one off item just for your application and will more than likely pass associated charges to, you may reconsider options.

 

[tkarvelis]

Thanks Guys. I am going to reach out to another company here in Pittsburgh.

I am wondering if I should put the engine back together or give it to them in pieces.

 

[racerxxx]

I use G4 media from my local supplier, it's glass bead. The paint Seadoo puts on will stick, ESPECIALLY the silver. I loath the silver engine parts, the white blows off much faster and easier. I have actually thrown silver engine parts to the side and used white ones just to save blast time. Soda blast is IMO for parts that are a bit more delicate, hence why guys use it on cars panels and fiberglass. When using sand on cars and parts it will generate friction and that generates heat. And heat will warp sheetmetal and ruin it and cost thousands more in body work. But the media blasters my buddies use for full restorations use many different medias depending on what they blast. But IIRC most use walnut shells on full body blasts. I think the last time I bought G4 I paid $13 for a 40# bag, always in stock and walking distance from my FIL's shop


This is the exact animal I use, just an older version.

 

[racerxxx]

This was right from the blast cabinet

 

[Sportster-2001-951C-Stock]

That's correct on the soda, and using soda will be difficult to remove heavy corrosion. One big advantage of soda is it's water soluble so you won't end up with hand fulls of beads stuck up in your crack. If you can deal with that then I say glass beads is good.

 

[racerxxx]

Unless you're in control of the bead blaster there is no way I would let anyone but myself blast an engine that is completely built. I have done it and have all the block off plates to do it.

 

[Spimothy Leary]

Unless you're in control of the bead blaster there is no way I would let anyone but myself blast an engine that is completely built. I have done it and have all the block off plates to do it.

agree, best when its apart, especially if it already is.

 

[racerxxx]

agree, best when its apart, especially if it already is.

Yes, but after a fresh rebuild I notoriously get grease on it and end up slapping the entire engine back in the blaster. It's very nerve racking.....especially when I did it to 1of500's engine I built for his 95.

 

[tkarvelis]

Well the engine is still apart, so I should be good there. I will see if they can do soda or g4 glass bead. I hope to head over to the shop outside Pittsburgh after work. I plan to soak the hardware in a carburetor cleaning basket to remove all the thread lock and gunk.

 

[racerxxx]

I bead blast all my hardware, that gets rid of everything

 

[racerxxx]

I pack the bores tight with shop rags and tape off the case halves. I will not blast bearing surfaces or the case mating surfaces. Look thru some of my build threads and you'll see what I mean, in my sig line.