Sanding "Orange Peel"

RG462 · #1 03-01-2008, 10:31 AM

Hi. I have been working with painting guitars for about a year now and have constintly run into the same problem. After putting on a coat of paint and sanding I get really bad orange peel look. Wet sanding does cut down on it, but it still looks pretty nasty in the end. Could it be the sand paper I am using? The paints? (Automotive and furniture spray cans) If I just keep sanding over it will it eventually go away? Just wondering if anyone else has run into this problem. Here are some pics of what I am talking about.

This is dry sanded, and extremely orange peely and scratchy. With wet sanding it is better but still you can see some.

Ibateur · #2 03-01-2008, 10:43 AM

Probably you are putting too much paint per coat, resulting in the first coat not being fully dry yet by the time you put the next coat. or you are going back and forth over the same spots with the can, during one coating run.

RG462 · #3 03-01-2008, 10:52 AM

thank you! That had not occured to me! I will consider this into my process

losgatosrg350dx · #4 03-01-2008, 12:29 PM

too much humidity, ro ur doing it inside wiht the heater on trying to speed up the process

and most lilkely u are using those automotive spray paint cans at kragens, wich are not reall automotive paint, but labeled and filled with something close to it

those paints require lots of air movement around them

if u use reall auto [paint, you wont have this problem but then u need to know how to thin it and add the hardener

RG462 · #5 03-01-2008, 12:39 PM

It is actually very dry here in colorado. The paint I am using is called Duplicolor acrylic enamel

losgatosrg350dx · #6 03-01-2008, 01:02 PM

oh ****, is ur guitar in a hot room near a heater

sometimes the heat can kinda"melt" the surface as it doesnt cure properly and it becomes soft and u get that effect when u sand it

i had the same thing happen with the duplicolor paint on one of my warmoth headstocks

but it was in a shed, wheere i lef tthe heater on, and came back every few hours after it was dry, then when i went to sand for clearcoat i got the same thing

so i ended up airbrushing and muxing my paint by hand, no duplicolor for me anyore

Racerx2k · #7 03-01-2008, 06:31 PM

Orange peel is caused by the droplets of paint drying before the are able to flow into the rest of the paint on the surface. This can be caused by to much air pressure, not enough air pressue, air temp, how fast of reducer you use, and distance. With rattle can you have little or no control over these variables.

- Not my words, but a direct quote from the Project Guitars Forums.

RudeRaptor · #8 03-01-2008, 11:14 PM

The Orange peel is normal , at least in automotive . I had 1970 camaro painted white by a guy who has been painting cars all his life . I help him wet sand it and he told me that orange peel look is normal .

I cant remember what grid we used and I'm not sure why yours is not smoothing out .

RG462 · #9 03-02-2008, 02:02 AM

well it is really ugly and nasty looking and I don't want it. lol

jazzedout · #10 03-02-2008, 03:31 AM

The orange peel is normal, you just have to wet sand...
I usually wet-sand with 800 grit between color coats and clear coats (I don't really take all of the orange peel off between coats because I am afraid I will go through it) and then wet sand with a 2000 grit after the final clear coat. This is where I take all of the orange peel of, since I know I have enough layers below the last clear coat. Then I use some automotive cutting paste, then a finer grade cutting paste, and then polish... It is a tiresome process, but I don't believe there is any other way to do it...
You must always be carefull when sanding, not to take all tha color, or clearcoat, layer of. You just want to smoothen the orange peel...
Hope this helps...

RG462 · #11 03-02-2008, 01:59 PM

if you sand after a clear coat with orange peel still showing, and clear over it, won't it be too deep in the finish to remove when you are using 2000 grit on the final coat?

jazzedout · #12 03-02-2008, 02:45 PM

I have done this with success in 2 of my projects....

papacueball · #13 03-03-2008, 10:53 PM

From the looks of your pics, the reason you're having trouble sanding out the orange peel is paint gumming up on your sandpaper. The most likely causes for this would be dust trapped under the sandpaper (the purpose of wet sanding is for the water to carry the dust away), or the paint is not dry enough to sand yet.

Also, a rubber sanding block with some 600 grit "wet-or-dry" sandpaper (usually black) works well for removing orange peel. Whether you wet sand or not, check often to make sure your paper is clean and remove any build up. Work in a circular motion, not back and forth.

It's not absolutely necessary to sand out all the orange peel, but the more you leave, the thicker the clear will have to be to fill the low spots of the orange peel.

Silver Sable · #14 03-04-2008, 01:47 AM

I didn't think you were supposed to use an enamel paint. I've never tried using any, so I'm not sure why, I just remember someone telling me not to do it.

TMatt142 · #15 03-05-2008, 07:11 PM

With my latest project, I made sure that in between coats of paint, I had very little to no orange peel. When it came time to clear coat (rattle can). I sprayed 5 coats before touching it. I then sanded out the orange peel with 1000....then 2000. Then I applied another 5 coats of clear and repeated...and so on. Once your finished though, I recommend letting it sit for a few days to cure before you do any type of handling. This way, depending on what you are using for a clear coat, you won't get little finger prints that need sanding! Laquer takes awhile to harden up.