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-   -   Tip: Cutting and Buffing Paint (https://vansairforce.net/community/showthread.php?t=60631)

snopercod 06-21-2018 10:08 AM

Wow! Those 3000 grit Trizact discs really work well!


snopercod 06-24-2018 05:29 AM

I sense a lack of interest here, but I'm done cutting and buffing the wings. After the 3000 Trizact, I buffed with 3m Perfect-It #1 using a wool pad.



In the bright sun, I could see swirl marks so I bought a qt. of #2 polishing compound ($64 at the local paint shop!!!), and applied that with a flat foam pad. You definitely will want to mask off any control surface gaps and hinges lest you gunk them up with compound. It would also be smart to mask off adjacent areas because that compound slings everywhere.



After cleaning off the #2 Polishing compound, I could still see some fine swirl marks, but I said "screw it". In the shade, my wings have a mirror finish now.


DanH 06-24-2018 08:49 AM

John, nice job.

If I were fine-tuning a new guy in the detail shop...

We quit wool pads years ago. There are polish pads available, but most of the common wool pads are cutters, a method which predates the fine grit abrasive disks you used. I think you would have had fewer swirl marks using a 3M white foam pad. Switch to a black pad for the swirl remover.

The photos appear to show too much compound. You want enough to wet out the surface, but not so much that the pad surfs up off the surface on a layer of liquid. Buff to near (but not quite) dry. You'll hear the machine begin to load up, and the pad will get warm. Go less dry with the last polish/swirl remover step. Think of it this way; we're removing material to make the surface microscopically flat, not adding material, as we would with a wax application.

Aluminum 06-24-2018 02:26 PM

Quote:

Originally Posted by snopercod (Post 1268975)
You definitely will want to mask off any control surface gaps and hinges lest you gunk them up with compound. It would also be smart to mask off adjacent areas because that compound slings everywhere.

Of the two kinds of compound I used neither mentioned a key piece of info on the container: it is in fact water-soluble. A foamy bath with microfiber cloth will remove most residue from crevices. But yes, keep the compound out of hinges and bearings as it will abrade them in principle (no cause for worry in practice, very soft abrasive).

Concur with DanH on the use of foam discs not wool bonnets (Harbor Freight ones are fine); they come in different foam stiffness for different steps and leave no swirl marks. After use I wash away the goop from the foam under running water and centrifuge it out at max speed, they last a long time that way. Pro videos show removing dried compound with a screwdriver. I don't like this method as it makes airborne mess and ruins the foam quickly.

Contamination from residue of coarser grade compound will leave visible swirl marks, must wash well between steps!

snopercod 06-24-2018 05:37 PM

Dan H and Dan V: Thanks for the encouragement and tips. I still have to cut and buff the fuselage so I'll ditch the wool pad and go with foam pads from Harbor Freight. Question: Will waxing hide swirl marks? I don't want to wax yet because I intend to paint some colored trim first.

P.S. The foam pad I used with the Perfect-It #2 said, "Machine Wash" so that's what I did. I tossed in the washing machine with my microfiber cloths on the "delicate" cycle. The foam pad seemed to come through that process intact. LOL!

snopercod 06-25-2018 12:25 PM

uk_figs little nib file got me to thinking. It looked exactly like my Dad's old aluminum file that I had in the tool box. So I got it out today and tried it out. It worked great for removing drips and runs on a convex surface. The serrations cut right into the drips and sags, but skittered right across the adjacent areas without cutting them. Thanks for the tip, Figgs!


Canadian_JOY 06-25-2018 01:12 PM

I have a bunch of cutting and buffing to do - really appreciate this on-going discussion. Haven't yet found the Trizact discs locally so am planning on doing 600 wet, 1000 wet, 2000 grit 3M Perfect-It buffing compound and 3000 3M polishing compound. I have the 3M foam pads and they seem to work well. Don't have the ability to use air tools (limited by electrical supply, can't run a big compressor) so will be doing it all with electric tools. Have a Makita 7" professional variable speed polisher and a Porter-Cable 6" variable speed random orbit polisher. I'm open to suggestions, given these limitations, of the best way to move forward.

snopercod 06-25-2018 01:53 PM

It seemed to me that hand sanding worked just as well (or maybe better) than using the DA, so I think you'll be fine. The Trizact seemed to work a LOT better than the plain papers, but I only used the 3000 grit Trizact. If I had it to do over again (oh wait, I still have my fuselage to do), I would use the Trizact 1000 and 1500 before the 3000. Amazon.com carries the Trizact products; They deliver to Canada, right? Don't worry, if a klutz like me can do this, anybody can.

az_gila 06-25-2018 02:44 PM

Quote:

Originally Posted by snopercod (Post 1269306)
uk_figs little nib file got me to thinking. It looked exactly like my Dad's old aluminum file that I had in the tool box. So I got it out today and tried it out. It worked great for removing drips and runs on a convex surface. The serrations cut right into the drips and sags, but skittered right across the adjacent areas without cutting them. Thanks for the tip, Figgs!

.....]

Looks like one of the ready made versions is the same thing, but shortened way down and with the edges rounded off to prevent digging in -



http://www.tcpglobal.com/STE35250_2.html#.WzFTo6dKhhE

Looks really easy to make a DIY copy. :)

David Paule 06-25-2018 03:02 PM

What's the difference between these and the Vixen files I've been using on my airframe?

Dave


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