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#1 wsmorton Oct 04, 2012 05:53 PM

Polishing Wings
 
2 Attachment(s)
Hi!

I finished painting the top of some Eraser wings and the finish is less than perfect. There's lots of small specks of paint on the entire wing, like that on a popcorn ceiling, but a lot smaller. What's a good way to polish out the wings to smooth out those small specks and then to get that high gloss look?

I would prefer not to hand polish the entire wing and would like to use something like a small orbital sander (electric or pneumatic), but don't know what to use and if they are OK for wet sanding.

Please include any tools, compounds or special equipment that you use.

Thanks and Happy Sanding!

Scotty

#2 dephela Oct 04, 2012 06:18 PM

I use 600 wet and polish with #7 polishing compound. Glass smooth and shiny!
By hand.

#3 s2000 Oct 04, 2012 06:55 PM

No way will a machine polish work to start, you have to wet sand with a block, 600 grit might work but I like 1000, then you go back and machine polish

#4 BigSwede Oct 04, 2012 10:25 PM

Yup, you'll need to wet sand that out. Be very careful not to sand through the color coats. I would start with 1000 (using a foam sanding pad) and then go to 1200,1500, and then 2000 grit. Finally I use a polishing compound on a pneumatic polisher with a 4" buffing pad.

#5 ak79 Oct 04, 2012 10:54 PM

Yes I echo everyone. From years of experience painting bikes and helmets, when you give someone an orbiting polisher that has never done it before usually they burn through the paint. So it might be better to grit your teeth and buff those wings out by hand after sanding.

#6 s2000 Oct 04, 2012 11:02 PM

Not too dissimilar from when I spray a wing, when that pesky gnat decides he wants to die in my newly sprayed wing, either use a deft quick yank with tweezers and spray an extra flow coat, or don't worry about the insect and sand and buff him out, same as the grit described above.

#7 wsmorton Oct 05, 2012 08:44 AM

I did find a pneumatic mini (2") random orbital sander/buffer that I might use for the final polish, but to be safe, I'll take AK79's advise to not burn through the paint, and do it by hand. Better to take forever than to ruin it and have to start over. When I'm done wet sanding, I'll use the #7 White Polishing Compound for the final touch.

BigSwede: Foam Sanding Pad? Do you mean a sanding bar with a layer of foam or rubber between it and the sandpaper? Or one of those all foam sponge sanders for furniture? Or something different? Also, do you have a link to that 4" buffer? I may have to get that and start practicing for the next set of wings.

Looks like I just need to take my time with these wings. Hopefully, the're be done by next year for the Southwest Classic.

Since this is going to take me a while, I'm also thinking of breaking out my old airbrush. I just can't decide on a pattern. Flames? Roadrunner and Wile E. Coyote? Poka Dots? Stars and Stripes? A Sci-Fi theme? Water Drops? A School Eraser? ;>)

Scotty

On a side note about buffing: A friend of mine tried to buff out a scratch on his watch with a Dremel and polishing bit..... He ruined the watch with one pass. Good thing it wasn't his expensive watch.

#8 podrieger Oct 05, 2012 09:28 AM

Finesse after 2000 grit
 
Big Swede suggestion is excellent. I use to do boats and cars and this is the normal process. Wet sand with 1000 grit to 1200 to 1500 then to 2000 grit. Then use a product called Finesse by 3M. This is a polishing compound specifically designed to remove 2000 grit sanding scrathes. This will give you a mirror finish on the wing.

As everyone has cautioned you, be careful not to go through the paint. Sometimes I start at 600 to 1200 to 2000 to save time. Try a small sample to experiment with.

3M Finesse can be bought at marine stores, auto suppliers and even Walmart. I believe they call it Finesse-It II now.

Good Luck
Phil

#9 BigSwede Oct 05, 2012 10:52 AM

Quote:

Originally Posted by wsmorton (Post 22919320)

BigSwede: Foam Sanding Pad? Do you mean a sanding bar with a layer of foam or rubber between it and the sandpaper? Or one of those all foam sponge sanders for furniture? Or something different? Also, do you have a link to that 4" buffer? I may have to get that and start practicing for the next set of wings.

Auto paint supply stores sell a variety of foam pads for sanding. There are different densities and shapes to chose from, and some with harder rubber backings. These are similar to a bar with rubber backings. On a airfoil shaped surface, I find it better to use a rubber-backed foam pad than a bar, because a foam pad follows the contour a bit better.

#10 georgeg Oct 05, 2012 03:29 PM

Quote:

Originally Posted by wsmorton (Post 22919320)
I did find a pneumatic mini (2") random orbital sander/buffer

Where did you find this?

#11 wsmorton Oct 05, 2012 03:45 PM

I found the mini random orbital sander at Harbor Freight web site.

http://www.harborfreight.com/air-ang...der-93629.html

I would be a bit too fast for sanding the wings, but it might work OK for polishing.

Scotty

#12 BigSwede Oct 05, 2012 04:42 PM

That's pretty much exactly what I use, but with a 4" pad. Works great for polishing.

#13 Wiker Oct 06, 2012 05:08 AM

Myself I would not use any type of machine sander. Sanders are flat, wings have curved surfaces. Way too easy to go through the finish with a sander. Myself I get much more feeling and control sanding curved surfaces by hand.
And - this a one-time job, and wet sanding a set of wings to get a smooth finish actually is not that much of a job anyway.
Buffing/polishing by hand is the part that makes me sweaty.

Here’s a good source for finishing stuff:
http://www.stewmac.com/shop/Finishin...,_buffers.html

What works for me is sanding to at least 2000 grit, and the simply polish with Nu Finish Scratch Doctor using a simple foam pad in and ordinary drill.
http://www.stewmac.com/shop/Finishin...hing_Pads.html

#14 Soarmark Oct 06, 2012 09:42 AM

Yep, +1 on the hand wet sanding to 2000 grit. Then polishing with a good fine polish, If you want a high end polisher here's a link to one. They deal in high quality products for people who are anal about their cars. I'm not associated to them in any way, but have used some of their products. Since you aren't going into production or doing multiple cars by hand is safer and cheaper.

http://www.griotsgarage.com/product/...ortby=ourPicks

#15 wsmorton Oct 06, 2012 12:04 PM

Thank you for links to the buffers and pads. I'll go through them to see what I might use the most.

I picked up some 1000, 1500 and 2000 grit wet/dry sandpaper today and plan on using those to sand down the wing. I also found some #7 White Polishing Compound that I'll use to polish the wings after I'm done sanding. I'll go ahead and do everything by hand, but will keep an eye out for those buffers for the next project.

Thanks!
Scotty


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