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geekhack Projects => Making Stuff Together! => Topic started by: zennasyndroxx on Tue, 13 May 2014, 13:56:45

Title: spray painting screwed up!
Post by: zennasyndroxx on Tue, 13 May 2014, 13:56:45
I was trying to spray my keyboard cover over the weekend.

I didn't realize that I was spraying it too thick and some parts uneven at all. After realizing what was done wrong compared to the guides here I really regret what I've done.

Any tips to remove the existing paint sprayed to it?

Also, wet sand means sanding it while its wet right?
Title: Re: spray painting screwed up!
Post by: CPTBadAss on Tue, 13 May 2014, 13:57:52
Yes wet sanding means you sand it while it's wet. Try wet sanding the paint down then reapplying the paint.
Title: Re: spray painting screwed up!
Post by: Tarzan on Tue, 13 May 2014, 14:02:28
Yes wet sanding means you sand it while it's wet. Try wet sanding the paint down then reapplying the paint.

Just to clarify, since I read that two different ways.   ;D

Wet sanding is sanding with sandpaper and water, after the paint has dried.  Not sanding while the paint is still wet.

Doing it the other way around will result in some really gummed-up sandpaper.
Title: Re: spray painting screwed up!
Post by: mkawa on Tue, 13 May 2014, 16:13:59
when you're wetsanding, you need to use waterproof sandpaper, such as the norton blue back series of papers. with those papers, norton recommends soaking the paper in water for about 5-10 minutes before sanding. it provides a very very clean finish at higher grits.
Title: Re: spray painting screwed up!
Post by: zennasyndroxx on Tue, 13 May 2014, 20:59:26
Yes wet sanding means you sand it while it's wet. Try wet sanding the paint down then reapplying the paint.

Just to clarify, since I read that two different ways.   ;D

Wet sanding is sanding with sandpaper and water, after the paint has dried.  Not sanding while the paint is still wet.

Doing it the other way around will result in some really gummed-up sandpaper.

thanks man :D i really screwed up my case now :<

when you're wetsanding, you need to use waterproof sandpaper, such as the norton blue back series of papers. with those papers, norton recommends soaking the paper in water for about 5-10 minutes before sanding. it provides a very very clean finish at higher grits.

would it be okay if i don't use waterproof sandpaper? i'm afraid that it's not available in my local hardware store

Yes wet sanding means you sand it while it's wet. Try wet sanding the paint down then reapplying the paint.

yeah, the paint is dried and i've wet it and sand it. seems better. if i would like to take the paint down (maybe not completely) should i use 50 grits?
Title: Re: spray painting screwed up!
Post by: mkawa on Tue, 13 May 2014, 21:13:14
wet sanding paper is definite at your local hardware store. it may not be norton, but any paper over 1000 grit will be a wetsanding paper
Title: Re: spray painting screwed up!
Post by: fohat.digs on Tue, 13 May 2014, 21:13:40
Yes wet sanding means you sand it while it's wet. Try wet sanding the paint down then reapplying the paint.

Just to clarify, since I read that two different ways.   ;D

Wet sanding is sanding with sandpaper and water, after the paint has dried.  Not sanding while the paint is still wet.

Doing it the other way around will result in some really gummed-up sandpaper.

thanks man :D i really screwed up my case now :<

when you're wetsanding, you need to use waterproof sandpaper, such as the norton blue back series of papers. with those papers, norton recommends soaking the paper in water for about 5-10 minutes before sanding. it provides a very very clean finish at higher grits.

would it be okay if i don't use waterproof sandpaper? i'm afraid that it's not available in my local hardware store

Yes wet sanding means you sand it while it's wet. Try wet sanding the paint down then reapplying the paint.

yeah, the paint is dried and i've wet it and sand it. seems better. if i would like to take the paint down (maybe not completely) should i use 50 grits?


50 is horribly rough. Start with about 150+ and go to several hundred at least.
Title: Re: spray painting screwed up!
Post by: zennasyndroxx on Tue, 13 May 2014, 21:21:12
wet sanding paper is definite at your local hardware store. it may not be norton, but any paper over 1000 grit will be a wetsanding paper

i'm sorry if this is a really stupid question but 1000 grits good for stripping down paint? might not have to be a complete strip though. just enough to remove bumpyness that i've made

Yes wet sanding means you sand it while it's wet. Try wet sanding the paint down then reapplying the paint.

Just to clarify, since I read that two different ways.   ;D

Wet sanding is sanding with sandpaper and water, after the paint has dried.  Not sanding while the paint is still wet.

Doing it the other way around will result in some really gummed-up sandpaper.

thanks man :D i really screwed up my case now :<

when you're wetsanding, you need to use waterproof sandpaper, such as the norton blue back series of papers. with those papers, norton recommends soaking the paper in water for about 5-10 minutes before sanding. it provides a very very clean finish at higher grits.

would it be okay if i don't use waterproof sandpaper? i'm afraid that it's not available in my local hardware store

Yes wet sanding means you sand it while it's wet. Try wet sanding the paint down then reapplying the paint.

yeah, the paint is dried and i've wet it and sand it. seems better. if i would like to take the paint down (maybe not completely) should i use 50 grits?


50 is horribly rough. Start with about 150+ and go to several hundred at least.

just to strip down the paint first?
Title: Re: spray painting screwed up!
Post by: PointyFox on Tue, 13 May 2014, 22:58:09
1000 grit should work.  Or you can do something like 400 then 1000 to save some time.  Just make sure the paint is dry or you'll end up with a gummy mess.
Title: Re: spray painting screwed up!
Post by: zennasyndroxx on Tue, 13 May 2014, 23:07:00
1000 grit should work.  Or you can do something like 400 then 1000 to save some time.  Just make sure the paint is dry or you'll end up with a gummy mess.

i'll try the 1000's to strip down paint then :D thanks!
Title: Re: spray painting screwed up!
Post by: dook0 on Wed, 14 May 2014, 11:21:22
Just to be clear with sandpaper (we never know), lower the number is, rougher is the sandpaper.

Usually for in modeling hobby, we use 500 then 1000 then 2000 to have a very polished surface, and apply the painting after that.
In your case if you think you have too much paint, you shouldn't go with 1000 (1000 or higher are generally made for the finish (before and after applying some coatting))
Title: Re: spray painting screwed up!
Post by: Findecanor on Wed, 14 May 2014, 13:44:54
wet sanding paper is definite at your local hardware store. it may not be norton, but any paper over 1000 grit will be a wetsanding paper
Any grit over 400 would be unnecessary for removing the excess paint, really. If you sand it smooth with 400, any remaining imperfections will be filled by your primer.
1000 grit and above is for fine finishing between coats, to remove slight bumps for getting a perfect smooth finish.