Spray paint puzzler

[Jopapa]

I went to spray paint the underside of a clear pickguard. I didn't want the edges to get stuck to the ground. So I reached into the our recycling bin and pulled out an empty mackerel can. The can was rectangular with rounded corners--like a sardine can, but smaller.

I placed the pickguard upside down on the mackeral can and sprayed it. After it dried, I picked it up to inspect it. I found that the area over the mackerel can was noticeably lighter. Does anyone know why? I'm stumped.

Again, the can was underneath the pickguard and being used simply as a means to keep the pickguard raised slightly. Here's some photos. Hopefully, you can see the lighter spot.

 

[Emergence]

Maybe the color will even up with another day to dry. If not, why not a second coat?

 

[Jopapa]

why not a second coat?

Actually, what's pictured is the pickguard after a second cost was added.

 

[drmilktruck]

I would tape off the top and edges and respray the bottom lying flat without the mackerel can. I've sprayed several pick guards and pickup bezels that way and have never seen that.

 

[6187LX]

This is a puzzler for sure. Were you spraying in the sunlight? The only thing I could think of is that the metal can was warmer than the surrounding area and caused the paint to adhere differently from the rest of the pickguard. I'd strip the paint and try again with more temperature neutral material, e.g. wood.

 

[Jopapa]

This is a puzzler for sure. Were you spraying in the sunlight? The only thing I could think of is that the metal can was warmer than the surrounding area and caused the paint to adhere differently from the rest of the pickguard. I'd strip the paint and try again with more temperature neutral material, e.g. wood.

It’s got to be something like that. Incidentally, there was no sunlight. I did it in the garage with the door closed. I’m too lazy to strip the paint. I just ordered another clear pickguard and another Gretsch decal.

 

[Zeek]

I would say over spray blew up under it as it was lifted up by the can and no over spray got to all of it it because of the can ....... but no over spray on decal ???
Was the decal put on after the paint ?

 

[Jopapa]

I would say over spray blew up under it as it was lifted up by the can and no over spray got to all of it it because of the can ....... but no over spray on decal ???
Was the decal put on after the paint ?

The decal was put on before the paint — underneath.

 

[Jopapa]

I would tape off the top and edges and respray the bottom lying flat without the mackerel can. I've sprayed several pick guards and pickup bezels that way and have never seen that.

Thanks but quick question. If I lay it flat on its top (so I can spray the underneath), why would I need to tape the top?

 

[drmilktruck]

Thanks but quick question. If I lay it flat on its top (so I can spray the underneath), why would I need to tape the top?

I do that because I have seen the paint bleed around the edges and also have embarrassingly picked up the newly painted piece and smeared paint where it shouldn't go. I like to tape off anywhere I don't want paint to go!

 

[Jopapa]

I do that because I have seen the paint bleed around the edges and also have embarrassingly picked up the newly painted piece and smeared paint where it shouldn't go. I like to tape off anywhere I don't want paint to go!

Got it. Thanks.

 

[GreTschocaster]

Well i am no scientist but the spray paint contains metalic particles and the mackerel can as well. If the metals are dissimilar there could be some kind of magnetic/electric reaction that may push/pull particles from/to each other. It may be my own perception but there appears to be a slightly darker ring around where the can meets the pickguard.
Again this is just my own theory. Maybe someone more knowledgeable can confirm or disprove this.

 

[Zeek]

The decal was put on before the paint — underneath. View attachment 209149

Then safe to say thats not it.

 

[Jopapa]

I tried again this morning. It's been drying in my garage. I taped up the other side per @drmilktruck so I can't take a peek to see if it worked.

​

 

[Hammerhands]

I wonder if it has to do with static electricity?

 

[Ricochet]

The spray hitting the can creates mini vortices, resulting in uneven distribution of paint particles?

Honestly I have no idea. Why not lay it flat if you're not hitting the sides?

 

[Jopapa]

Mystery unsolved, but pickguard done.

 

[Henry]

Feel The front of the pickguard, maybe with eyes closed. Maybe try to clean the front with diluted (or not) paint thinner.

My guess is that the spray creates a small cloud of spray that got underneath, but was blocked by the sardine can.

 

[Jopapa]

Another question: Is there any potential harm in spraying on another coat (to the back)? Would it make it less susceptible to peeling? Or should I just leave well enough alone?

 

[Henry]

I don't know about peeling, but if the pickguard is still a little translucent (try putting something opaque like a book against the back and see if the color tone from the front changes) then another layer will darken / deepen the gold color.