Interesting analysis Media Blasting our cars' parts
 

I have a broken drivers handle latch mechanism on my 1981 car, same thing in my 1989 car which I fixed. However, this 1981 car is coming down all - the - way as my 89 comes back together. Sometimes, I can work into my work load my stuff, which said Door I just removed and gutted and send it to the pile for next-up blasting. While I was at it, I removed the Hood and Trunk and prepared them and sent them over to the pile for blasting. Well. The Door and Hood is aluminum as you all know, the Trunk lid is steel. The attached photos show the rust on the Deck lid, and the attached photos after media blasting shows a majority of the galvanizing remains intact. Now, I was not seeking preservation of this protection as primary, only removing the rust as primary objective. But, the media mix I use I've developed over many years which gives me the fastest and most gentle process which means most efficient process. As you can see, most of this protection remains where the rust was NOT, where the rust was is clean but no galvanizing remains.

Door: extensive lower lip corrosion resulting in failed spotwelds. Hood: Now this was the bugger! The paint on the inside of the Hood was tough, very stout and very embedded into where it was applied and certainly didn't want to budge. I ran this Hood as an experiment to gather time costs, and, how it sustains an onslaught of media blasting operations. I took risk on my things so I can be learned when I do customers' things. I have learned what I need to learn. I have a clean Hood, in Epoxy primer and some surface smoothing operations are being undertaken. Again, all internal assessments and analysis.

Repairs: Door I applied epoxy primer to the entire door, then 3M Panel Bond to the lower lip corroded surfaces which will bond the halves together, and fill the holes. Some of the 'hack job' a previous owner did on the attempts to install speakers I'm welding in new aluminum panel segments and will dress accordingly. Remember, I have set-out to master this automobile in my head and in practical applications. Many assemblies I have and am subbing out to 'experts' for their touch as I can't and won't tackle everything. https://cimg0.ibsrv.net/gimg/rennlis...41dd7c4dee.jpg
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How would your media mix work on the front bumper? I've used a spray paint remover for plastic parts, which worked, but left behind a hard residue on the surface. Bumper had been painted many times.

james

LOL, I thought this was a thread about the news media doing an unflattering report about Porsche car parts...

Fake news! :D

I'm researching this as well. Going with soda blasting - good for most surfaces - not good for rust. HF has a decent unit that holds 40# of blast media. Starting on big stuff like suspension parts I have piled up. If that turns out well, I'll invest in a decent blasting cabinet. My head guy uses glass bead and his results are really nice. Had him bead blast some front rotors and a water bridge. Here's how they turned out.

https://cimg9.ibsrv.net/gimg/rennlis...9db792f04.jpeg

I've not yet done a front or rear fascia for these cars, but I've done a BMW 840 front fascia with no deleterious effects - ready for painting. As far as investing in a blasting cabinet - we may be on different playing fields as me investing in a blasting cabinet is around $20,000.00, and in one minute of media blasting I've already shot 25 pounds of media out of the $150.00 nozzle. So, please remember I engage in this as a hobby but only sprinkled in with paying jobs as I'm The Doctor at drblast.com

Kevin, for the hoobyist, a Skatblast cabinet, soda attachment, and a decent vacuum is about $900, and another $1200-1500 for an adequate (15+ cfm) 5 hp compressor. I switch between soda for engine bits and glass for most everything else. Unless you have a dedicated shop, a toploader is key- less mess and no need to keep a clear space to the side for loading/unloading. The door is 'only' 30" x 14" and it's 14 to 18 inches deep- it'll swallow a 16" 928 wheel, if necessary. It certainly won't do body panels but for cleaning up anything else on a 928 it's sufficient.

https://webfiles.uci.edu/redwards/pu...2012-29-17.jpg

https://webfiles.uci.edu/redwards/pu...2012-29-17.jpg

Wait- did you say your head guy uses glass beads? As in cylinder head guy? I really don't think that's a good idea.

I know, I heard the same from GB on more than one occasion. But, I have the most meticulous machinist and he cleans the heads thoroughly.

I am not that good, that's why I'm planning to use soda.

Me either, that's why I got the soda attachment. :) Just thinking about the surface area and casting porosity in a 4V head for entrapped glass gives me nightmares.

That sounds about right for my needs. Model # for that unit? I have an 80gl air compressor.

I would like to also be able to soda blast engine blocks on their stands. Do you think it's possible to plumb that?

Kevin

Mine is a Skatblast 780TL, I don't think they make that model any more. The equivalent would be the 33V;

http://www.tptools.com/USA-SKAT-CAT-...html?b=d*41308

Soda attachment:

http://www.tptools.com/Skat-Blast-Di...*soda+blasting

They do make a standalone that I bet would work for blasting engine blocks but that's hugely messy. I usually just de-grime engine blocks as much as possible with a plastic scraper and paper towels to capture most of the crap, then pressure wash, then finish in my 30 gallon parts washer, a bare block is only 80 pounds so it's doable. The problem with soda is that the runoff is highly alkaline and will kill the grass, if you care about such things. .

I found a Safety-Kleen washer at a pawn shop a couple of years back, I have it serviced once a year or so, for about $200.

https://webfiles.uci.edu/redwards/pu...%201-22-15.jpg

I suppose if I can get an oil pan, heads and whatnot I'll be fine.

Do I need a foot pedal?

I don't use one, I'm never blasting for long enough that my hand gets tired (30 minutes or so max, when doing batches of hardware).

It is worth splurging for the carbide nozzle, they're $50 but even with light use steel and ceramic tips wear out fast enough that it's annoying.

How long in those cabinets will it take you to do one control arm? What's your time worth? I say this only because I've been there and done that. Any sort of blasting is not measured on how many gallon air tank you have, it's CFM. You will likely need a higher reserve air capacity than the numbers you all have floated around. It's not proper to do the math with the idea "I have enough air", you must have reserve capacity. Our cars have 300hp, but we do not use it all the time at all speeds -- we have it when needed. Frankly, you're wasting your time on that Harbor Freight junk. Here's a cabinet:
https://cimg1.ibsrv.net/gimg/rennlis...5935c915b9.jpg

And this is still too small for some jobs...
https://cimg7.ibsrv.net/gimg/rennlis...28a050e2ec.jpg

S4 intake, blasted, and in epoxy primer, and in a dull aluminum paint color.
https://cimg4.ibsrv.net/gimg/rennlis...1f298e1b4d.jpg

Before blasting.

Any of my time spent with 928s is pro bono, so by definition it's worth zero :) Your point is well taken, though- With the medium flow carbide nozzle, my dinky cabinet consumes 12-15 cfm at 80 psi, my compressor is rated at 15 cfm at 90 psi, so it keeps up, but just barely. I would love a larger blast cabinet but I am stuck with a single 22 x 15 foot garage space so as a home hobbyist I have to make do. Would love to be able to do what you do! :thumbup:.