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Job done-photo update. re:-how do I prevent / fix air bubbles in my epoxy?

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  • Member since
    October 2004
  • From: Mississippi
  • 819 posts
Posted by ukguy on Sunday, February 27, 2005 12:46 PM
earlier today I did my first mix of epoxy for my river, i stirred slow and poured carefully, the base ws sealed. as I was pouringalot of air bubbles appeared, I remembered I had read that to draw these out use a hairdrier. I did this and sure enough the majority of the bubbles shot to the surface and vanished. unfortunately the 12min epoxy started setting and unsightly ripples(not realistic or desired) began appearing.
When I came back about 2hours later there were still alot of bubbles but 95% had risen to the surface. I got a pin and punctured all that I could get though to.

1)Will my second pour now fill these little holes in invisibly or should I give it a thin coat of high gloss poly to eliminate them as this would probably get into the small holes better.

2)If I can eliminate the bubbles from my first pour how do I prevent it from happening on my second pour? Should I get a slower set epoxy?

3)Short of grabbing a chisel and trashing the surrounding scenery to get out the epoxy have I ruined my layout[:(!] and now have to look at a disaster which I know will drive me crazy.

Any help and advice is gratefully recieved.

be safe and have fun
Karl.
  • Member since
    November 2001
  • From: US
  • 732 posts
Posted by Javern on Sunday, February 27, 2005 1:23 PM
I suggest not to hold the hair dryer so close as to make ripples, i use a heat gun myself which is a hotter heat.
  • Member since
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  • 180 posts
Posted by 2021 on Sunday, February 27, 2005 8:00 PM
If you mix the epoxy EXACTLY according to directions, you should be okay. I have done this numerous times with no problem. My guess is you may have waited to long or not mixed carefully - it really is that critical. As for the area you don't like maybe you can paint over it and try again. Keep the layers of epoxy thin. Good luck.
Ron K.
  • Member since
    September 2003
  • From: North Central Illinois
  • 1,458 posts
Posted by CBQ_Guy on Tuesday, March 1, 2005 12:48 PM
My understanding is that it is carbon dioxide which gets rid of the bubbles. Therefore you are directed to simply blow on the epoxy if it's a small body of "water", or to QUICKLY run the flame from a propane torch back and forth over the epoxy several times. I've seen this actually work on a scenery video by Dave Frary, btw, so it's certainly no "urban legend".

Good luck!
"Paul [Kossart] - The CB&Q Guy" [In Illinois] ~ Modeling the CB&Q and its fictional 'Illiniwek River-Subdivision-Branch Line' in the 1960's. ~
  • Member since
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  • From: US
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Posted by wp8thsub on Wednesday, March 2, 2005 12:06 AM
Don't do anything drastic just yet! Epoxy resin cures with a smooth surface that doesn't represent most water very well, so don't consider the epoxy as a final step.

I use epoxy resin as a base because it does a far better job than most products at representing water in pours of over about 1/8". With a little color added from enamel paints it creates a nice representation of depth. What it lacks is a realistic surface texture. Coat the epoxy with a textured application of acrylic gloss medium. Gloss medium is basically a thin, untinted paint. Bigger waves can be added with thicker media like acrylic gel medium. Either acrylic product is easy to apply with a soft brush, and the gloss medium tends to level out somewhat as it dries so you don't have to worry too much about how your ripple pattern looks.

Nothing you've done should be considered an emergency. I've finished a lot of water using epoxy resin covered with gloss medium, as have a number of the guys I model with. You can almost count on a few bubbles developing in the epoxy, which combine with the otherwise mirror-smooth surface to virtually beg for an additional finishing step. Look at it like this: if you install your track on cork roadbed, you still need to add ballast to make the whole installation look finished. Just as with cork, the fact that epoxy doesn't deliver an entirely finished product on its own doesn't mean there's anything wrong with using it; it's one step in a bigger process.

Rob Spangler

  • Member since
    October 2004
  • From: Mississippi
  • 819 posts
Posted by ukguy on Wednesday, March 2, 2005 12:35 AM
Thanks for the advice guys,

in the end I went ahead and opened the pin holes up a little more and did a second pour. This time I used a much longer set time epoxy, the first pour was 5min and I found myself rushing, prob the main bubble causer. time 2 I used 20min epoxy but I also put it in the microwave for 40secs before mixing. The result of this was that it thinned the liquids considerably making it much easier to mix, pour, control. because the epoxy was warm and so thin any bubbles(and there werent many) rose to the surface more easily and disipated.
Also as rob stated the epoxy isnt the final coat and I will be adding a 'top coat' of gloss medium for a ripple/movement effect so this should further hide any imperfections.

Here are a couple of pictures of the results so far, its not perfect but it is quite a good save from an originally disapointing start.




the clear plastic drinking straws will be cut down to water level or removed leaving holes, they are where the legs will 'submerse' for my fising pier.
Thanks again for the help.

Have Fun
Karl.
  • Member since
    April 2003
  • 305,205 posts
Posted by Anonymous on Wednesday, March 2, 2005 5:40 AM
So you wana get rid of air bubbles in your epoxy?, Easy borrow your wife's/lady's hair dryer set it on low hold over the work about 12 inches away and slowley move back and forth until bubbles disapear. Be carefull use common sense. Should only take about 30 seconds. I do this in my profession and my model work, Iam a painting contractor. Hope this helps out.

Take care, L.D.
  • Member since
    April 2003
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Posted by Anonymous on Wednesday, March 2, 2005 12:10 PM
You guys are always talking about using a gloss medium for a wave texture...but I've been reading around here for a couple of months and am still not sure how you actually texture in those waves! Does it happen as the gloss dries, or are you shaping it on there somehow?
  • Member since
    October 2004
  • From: Mississippi
  • 819 posts
Posted by ukguy on Wednesday, March 2, 2005 4:33 PM
Gloss Medium is a product I found at Michaels, it is a sealing finishing product I believe and is quite expensive. It has the consistency of really thick white paint, but dries clear gloss, so you apply it with a brush leaving brush strokes in the form of ripples which then dry to a clear glossy textured surface, you can then dry brush white to the tips of the 'waves' / turbulance to simulate whitewater or foam.

I used a pruduct I found at Wal-mart art section called Mod-Podge gloss lustre on another area to simulate rapids, its slightly thicker but dries to a clear high gloss, is half the price for twice as much.
Hope this helps, if any of this info is wrong I am sure someone will correct me.

Have fun and be safe
Karl.
  • Member since
    April 2003
  • 305,205 posts
Posted by Anonymous on Wednesday, March 2, 2005 5:30 PM
Cool, thanks. Good info.
  • Member since
    August 2003
  • From: Northeast Houston
  • 576 posts
Posted by mcouvillion on Wednesday, March 2, 2005 8:20 PM
ukguy,

Your epoxy water looks pretty nice to me. I love that scene. Post a picture when you are finished.

Mark C.
  • Member since
    November 2002
  • From: US
  • 2,455 posts
Posted by wp8thsub on Wednesday, March 2, 2005 11:15 PM
QUOTE: Originally posted by ukguy

Gloss Medium is a product I found at Michaels, it is a sealing finishing product I believe and is quite expensive.


Gloss medium has various uses with acrylic paint. It's a lot thinner in consistency than regular paint, while gel medium has much the same texture as tube acrylics. Good quality acrylic stuff isn't cheap, but enough gloss medium to do even a large layout can be had for under $10 and it lasts in the bottle for years.

QUOTE: ...you apply it with a brush leaving brush strokes in the form of ripples which then dry to a clear glossy textured surface, you can then dry brush white to the tips of the 'waves' / turbulance to simulate whitewater or foam.


Right. If you don't like how the first coat of ripples looks, add another one; it's almost goof-proof. I use a lot of white around rocks and other sources of turbulence to enhance the look of rapids. Gel medium works great for building up rapids.

QUOTE: I used a pruduct I found at Wal-mart art section called Mod-Podge gloss lustre on another area to simulate rapids, its slightly thicker but dries to a clear high gloss, is half the price for twice as much.


I forgot all about Mod Podge! I've used it in place of gloss medium before and it gives good results as well.

Rob Spangler

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