reverse painting

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reiddog1

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Oct 14, 2011
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Hey fellas, I have been painting my acrylic blanks with tester's and using epoxy with a drop of the same paint to glue in the tubes. Lately, I noticed an unpainted spot on the blank when finishing. I usually put at least two coats of paint in the hole with at least 12 hrs drying time between all steps. Cant find what I'm doing wrong! Any help would be greatly appreciated.

Dave
 
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robersonjr

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Hey Red Shirt, I don't think you are doing anything wrong except be careful when pushing the tube into the blank. You can sand the sharp edge off the outside of the tube to help it slide in easier, that works for me. Robbie
 

The Penguin

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the last few acrylics I did - I placed brass tube inside the drilled blank without gluing it.

put it on the lathe and turn it down most of the way

then remove from the lathe and paint.

you can shine a light through the blank and look inside the drilled hole to see if you missed a spot...couple coats of paint...then glue in the tube and turn to final shape.
 

Brooks803

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Another thing you have to be careful of is when you're drilling the blank. ANY mark made by the drill will be hard to paint. I think I have a pic....

If you look just under the clip ring you'll see all those little dots. That's from the bit not being sharp enough and tearing a bit out. Add in the heat buildup melting it in some loose shavings and you can end up with this:

DSC00603651x700.jpg


Besides having sharp bits and allowing everything to cool properly I've also add a step of polishing the inside of the blank with a brush made for cleaning air sprayers. I put the blank in my collet chuck and run the brush through it with it running. It really seems to help.

Same process but with polishing....red is only reverse paint, the blue was cast in clear resin:

DSC00898635x700.jpg
 

reiddog1

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I'm with Robert. Show us your brush. Your blanks are always so bad a** Jonathan. Have any of you guys used poly glue, like gorilla glue? Thanks for all the suggestions fellas.
 

Brooks803

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SteveG

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Some times when you paint the hole there will be a glob or drip clinging to the interior surface. Later when the paint is dry and you insert the tube, the tube will grab that blob and scrape it off. This leaves an unpainted spot which can show up on the more see-thru blanks. I deal with this by inserting and then removing the tube while the paint is still wet. This removes the glob (if there is one) but generally leaves a coat of paint still covering the area. You can wipe the tube off immediately to avoid adding significant paint thickness to the tube. Result: no holidays. Has worked for me in the past.
 

Carl Fisher

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Also be sure to check your fit before you glue. If the tube is a tight fit to begin with, the paint will likely just scrape off when you insert the tube. I've found on occasion that I have to go just a touch bigger on the hole to allow room for a paint layer and then use colored epoxy (just add a drop of paint to 5-min epoxy and mix) to secure the tube.
 

Chasper

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I suggest that the problem is Testors. Some colors are solid with good coverage, others not so good. There are two Testors colors I still use, but otherwise I've switched to acrylic craft paint. In addition to being thicker and providing better coverage of scratches inside the holes, the acrylics are in more colors, cheaper, and easier to find.
 
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Jim Burr

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I've had good results with rust-o-leum gloss black spray can stuff. Rough up the tubes with 200 grit sandpaper, I put a 3" screw in my vise at an angle, spray away! It dries really fast. I use a Q-tip on the inside of the blank. I posted that Agate pen last week, that with the other cool pic's here should give you a look see. Good luck!
 

jd99

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Ontario, CA United States
Some times when you paint the hole there will be a glob or drip clinging to the interior surface. Later when the paint is dry and you insert the tube, the tube will grab that blob and scrape it off. This leaves an unpainted spot which can show up on the more see-thru blanks. I deal with this by inserting and then removing the tube while the paint is still wet. This removes the glob (if there is one) but generally leaves a coat of paint still covering the area. You can wipe the tube off immediately to avoid adding significant paint thickness to the tube. Result: no holidays. Has worked for me in the past.
This is a good tip, I found this out accidently a while back, I always check the hole with a tube before I paint, I was doing a batch, and by mistake picked up one I just painted stuck the tube in and rotated it and pulled it out and that blank had a more consistant, and even coat I didn't have to give it a second coat, the tube helped spread the paint evenly around the hole.

I do it all the time now.
 

rfbosse

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Feb 16, 2012
Messages
6
Guys,

I was wondering if the white foam from polyurethane glue would work as reverse painting? I have been using the quick dry gorilla glue for wood and was thinking it might kill two birds with one stone for resin blanks.

Ray
 

CG39

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May 9, 2012
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Bountiful
Let me make sure I understand what you said. The black/dark blue is painted on the inside of the blank and the blue/white is a floating color in a clear resin? So how does the blue pock marks show up if it is reverse painted? I was under the impression that painting resolved this problem. Disclaimer, I have never done this process myself as I am still learning.

And the same with the red, black reverse paint inside the hole with a clear resin mixed with red?

Another thing you have to be careful of is when you're drilling the blank. ANY mark made by the drill will be hard to paint. I think I have a pic....

If you look just under the clip ring you'll see all those little dots. That's from the bit not being sharp enough and tearing a bit out. Add in the heat buildup melting it in some loose shavings and you can end up with this:

DSC00603651x700.jpg


Besides having sharp bits and allowing everything to cool properly I've also add a step of polishing the inside of the blank with a brush made for cleaning air sprayers. I put the blank in my collet chuck and run the brush through it with it running. It really seems to help.

Same process but with polishing....red is only reverse paint, the blue was cast in clear resin:

DSC00898635x700.jpg
 
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