Tin foil me?

[gstours]

  Hello all,  (rod finish common epoxys) just me wondering in the advance of sceince and common knowledge the question....
     Is using an aluminum mixing pan some type of an advantage over the compared type of paper or plastic type??   Just wondering?    Ive heated rod finish epoxys in paper and plastic and never thought better when needed without what I would call a Problem.   So is it an air trapment bubble thing ?  Thanks for chiming in.

[MarkT]

With Paper or plastic I'd just throw away when done. Aluminum, I'd want to clean and reuse.

[thorhammer]

Gary, I have been wrestling with micro air for the past couple years - I dunno what changed, used not to have an issue. I've been mixing in plastic dose cups for 30 years. I talked to a really good custom Heaver builder at OBX about it, and he said he gets them as well, but he uses an epoxy mixer in cup THEN pours the epoxy out in the foil pan to deaerate for a few minutes. The pans have to do with surface area mainly, vs a cup, the pan is wider and shallower. If there is a major difference in ability to break surface tension between the aluminum and plastic, that's a level of detail I'd go to in my job but not a hobby. If it persists, I'll just go back to black thread on black rod and you don't see anything. There's a reason why mass-produced rods use this scheme-hides flaws. I've not gone to the pans yet, but still might. The only reason is that I can get air-free in cup, but still get bubbles after application after thread saturates and also from the curing of the epoxy- I read that the chemical reaction can off-gas in and of itself, I dunno. I'm now using thread sealer, then epoxy, which may still bubble, then bubbles popping up in second epoxy coat, which should have no air popping out of thread at that point. Using alcohol lamp, some of these little bubbles aren't popping either, so then I'm thinking maybe the epoxy has changed....tried Diamond, Flex coat, pro kote, flex lite, and pro kote thinned with xylene, and I warm resin before use. Still some bubbles. Gonna try Threadmaster when I can find it, but I think there is something else happening, perhaps environmental with humidty in the shop but I haven't found it as a constant. Sorry for long wind, but been meaning to put this out there to see if anyone has ideas to get rid of these little bubbles. The only thing left I know of is to wait for the epoxy to cure a few minutes before application and brush even slower, but I never had to do that until the last several builds. Maybe the EPA has mandated a change in universal hardeners or something- that may explain why a tube of five minute is seven bucks that used to be three....you can search for pans under "weigh boat", they are used in labs for weighing chemicals and may come up cheaper, plus there are aluminum and plastic both.

[Swami805]

I use these foil trays I get from voodoo. I cut a little tan in the side so I can tilt it a little so it pools on the side

[thorhammer]

Sheridan, what finish are you using?

[Swami805]

I use D2 from voodoo. I've tried several and they all have their quirks, couldn't say one is better than another. I settled on D2 because the company is such a pleasure to deal with.

[thorhammer]

Voodoo has been on point for sure.

[JasonGotaProblem]

I use flex coat lite exclusively. Not because I've tried others and like this one best, but because it's the one I started with and I've had no issues. I saw some bubbles on the rod I built for Keith, and it was super memorable to me because I hadn't seen any in so long.

If I mix up a batch of epoxy and it seems excessively bubbly I'll add a few drops of acetone, stir it up, and all bubbles vanish. I've never noticed any issues in how it cures. Thinning it like this also helps it spread easier and seems to extend the workable time.

I always take a heat gun to my wraps after covering them, run it til it drips. then I hit them again about 45 minutes later if I remember. I only use a heat gun i dont ever use an alcohol lamp anymore. A heat gun can be set to a lower temp and aimed at the wrap til I'm happy with it. An alcohol lamp only has one temp - and it's too hot for prolonged exposure.
 And if I'm doing multiple coats I wait at least a day between. Outgassing is still a thing and giving it time makes it less of an issue. If you get a car painted they'll tell you to wait a few weeks before waxing for this reason.

Also when I do under wraps I epoxy them (thin coat) and let it cure before I wrap on the guides. I assumed everyone did that but recently learned otherwise. Maybe that's helping.

Also I stir my epoxy with a plastic fork. Every stir with a fork is equivalent to 5 passes with a stir stick.

[sabaman1]

After mixing smoothly and gently not with with a rapid swirling action in cup I pour into a tray I make out of just regular aluminum foil and most bubbles dissipate and if you slightly warm epoxy from a distance in tray with a hair dryer or heat gun bubbles pretty much are go away.

[Dominick]

Gary, I have been wrestling with micro air for the past couple years - I dunno what changed, used not to have an issue. I've been mixing in plastic dose cups for 30 years. 

John, Gary I read somewhere that the plastic dose cups contain a chemical (I think silicone) that causes bubbles.  The mixing cups sold by rod suppliers do not contain whatever it is that causes bubbles.  My two cents.  Dominick

[thorhammer]

Noted! Crap I put in mudhole yesterday

[sabaman1]

Noted! Crap I put in mudhole yesterday

Thor, the mixing cups mudhole sells are fine for mixing. I usually hold the cup at an angle and slowy work the mixing stik around the inner edge twirling the cup and that helps out alot at not creating alot of bubbles. Also putting a thin coat on first coat helps thread absorb epoxy and fill gap under front of guide foot which will bring up bubbles then you can blow warm air from your lungs slowly with a straw to help break any bubble you see pop up.

[thorhammer]

Thanks, Jim! Just ordered some weighboats. Weather is crrrraaappppp in NC right now, so Imma play in the shop this weekend.