How do you polish a firewall?

Ed_Wischmeyer · #1 07-09-2009, 05:45 AM

Will be pulling an engine, and this seems like a good time to detail things firewall forward. So how do you polish a firewall? What kind of polish or abrasive, what kind of polisher / pad, what speed, etc?

thanks!

Ed

f1rocket · #2 07-09-2009, 06:34 AM

I bought a stainless polishing kit online from Caswell. Link to kit

I have pictures on my website if interested.

It is not a quick process. Stainless is very hard and it takes many passes with a lot of pressure to get it cleaned up. I used mostly the Green bar (least abrasive) and the liquid swirl remover since the stainless is typically in good shape. The lesson I learned is to use a lot of pressure. I never got a "mirror" finish but it was close enough.

cjensen · #3 07-09-2009, 07:46 AM

I used the same product Randy did after he recommended it to me...works great, but it's no picnic. I didn't get a mirror finish either, but pleased with the results.

deene · #4 07-09-2009, 07:48 AM

I polished my RV8 firewall before I installed any items. I used Maquires (sp) metal polish that I got a local auto parts store. I used an old shop towel and about 1/2 hour to finish the job.

It came out pretty good, but not mirror perfect. I need to go back and touch it up now that I'm flying. I don't know how hard its going to be to polish around the firewall mounted stuff.

PropellerHead · #5 07-09-2009, 10:52 AM

I've polished all sorts of parts for projects, aluminum, stainless, brass...

If you go to Grizzly.com and get the random orbital sander bonnets, they are okay. Start with prepolishing liquid, then red rouge, then green fine, then high polish for stainless pink. After all that, hit it with liquid car wax.

All of this should be done with separate bonnets for each grade compound. Sharpie mark them before starting. Apply even pressure, but let the machine do the work.

After an hour or so, you should be able to shave in the reflection!

One more thing, use proper respirator and eye protection and wear a painter's cover-up suit. After doing big polishing jobs, you get covered with all the strings from the polishing wheels/bonnets and all the black oxide that comes off.

You will look like a Yeti when done if you do it right.

flyboy1963 · #6 07-09-2009, 11:41 AM

...okay, I only know how to Ukrainian a firewall. ( rimshot!)

..aren't you tempted to cover that beautiful piece of stainless with a nice, homely fireproof blanket?? If I had my engine off, that's what I'd be shopping for!

sorry....go ahead and buff away! mmmmmmmmm ... shiiiiiinnnnneeeeyyyyy!

Skypilot18 · #7 07-09-2009, 04:51 PM

Ed,

Have never polished a firewall but I polish a lot of stainless pieces. I use buffing compounds from Busch cleaning products. You can find them through Ask.com or Google. These are normally used with a wheel on a buffer but you can use a buffing wheel on an electric drill as well. It is obviously easier prior to installation but it can be accomplished. Stainless will definitely polish to a mirror shine and retain that for years in the protected environment of an aircraft firewall.

DanH · #8 07-09-2009, 05:28 PM

A Van's firewall is made from semi-polished sheet material, so unless you're a fanatic I'd skip the compound and wheels....it doesn't need a lot of cutting. You can get 95% of a buffer finish with hand polishing. Since you never look directly into a firewall you can't tell the difference.

My favorite general purpose aluminum and stainless polish is Met-All:

http://www.wicksaircraft.com/catalog...php/subid=8347
/index.html

They make a great brass polish too.

Rick6a · #9 07-10-2009, 08:33 AM

An alternative to polishing that renders a compelling result (at least in the examples I observed at a Boone Fly-in) is to burnish small circles onto to the stainless firewall, a technique sometimes referred to as "engine turning." The builders using the technique at Boone omitted just those areas of the firewall as to make RV-8 (or other lettering) jump out at you. Pretty dramatic effect. There once was a discussion about this but for the life of me I cannot find the information anywhere in the archives. Perhaps it was originally posted in the Test/Misc. area and has long since been deleted. Anyway, here is a picture of the intake ramps on my -6A using the "engine turning" technique. Hopefully, it will give you an idea of the finished look.

CMW · #10 07-10-2009, 11:54 AM

Here's another example of engine turning on my firewall. To do this, I laid out a 1" x 1" grid with a sharpie on the firewall and then used a 2" diameter Roloc scotchbrite wheel in a cordless drill. Took a while and I'm not sure it's worth the effort but it looks nice now.

Chris