Background for very specific question: I build small bore rods for bass and popping. A thread - No underwraps - No Cp. Use nearly all brands of finish each for a specific reason. Results are presently good. Technique of application is not the issue. Use multiple thin coats. Work in warm shop.

Mix finish, pour in aluminum pan, wait five minutes, apply to guides - takes about three minutes, apply to butt wrap - takes two minutes, stop rotation, flame butt area, remove excess finish from bottom, turn guide rings down, flame guides, check for excess, hand turn two to three times to check for sags and place rotating dryer.

Question: Is the result of the final set of the casting resin affected in any adverse way due to the flaming. These casting resins are pretty complex systems and I would assume that most develop their physical properties in a very fixed manner. The only finish that I do not flame is LS.

I have heated the remaining finish in the aluminum pan with the torch and noted the drastic reduction in set time. The finish in the pan will pass the finernail test a lot sooner in a pan that has been heated. When using some of the finishes the thin layer remaining in the pan becomes quite friable and will pop like a piece of brittle candy. I am wondering if this flaming can be a bad thing that will contribute to cracking in the guide foot area. The only reason that I do the flaming is to drop the viscosity of the finish on the butt wrap area so I can remove excess to get level coat. I flame the guides due to habit and could easily stop.

Gon Fishn

Bill,

When you refer to casting resins I assume you mean a typical two-part thread or rod finish. Aside from the initial drop in viscosity and faster reaction time, getting the system too hot could either degrade the components or advance the degree of cure to the extent that the finished material becomes much stiffer, or even brittle. Short of analyzing the materials it’s just an educated guess.

It might be hard to control the temperatures of the flame and the temperatures may be getting much hotter that you realize as demonstrated by the effect on the material in the pan. Another option would be to use a hair dryer to get the warming effect you're looking for from a more moderate heat source.

mark

GOOD QUESTION ! I use flex coat the standard mix not the lite coat. I am very careful about my mixing procedure to the point being obsessive.I posted a question under "sticky fingers" my final coat is not drying . I was wondering if my technique was wrong. I mix my flex coat and during the course I heat the mix with a hair dryer to the point where I almost burns my fingers , the F.C. has a watery consistency .I continue to mix and add heat .I get a bubble free and crystal clear finish when I'm through.Because of all the heat the drying time is decreased considerably.. I'm wondering if adding all this heat to the F.C. it's drying too fast and not letting the mix cure enough before hardening leaving the mix sticky to touch?? I use no additives.

Bill Cohen: I put the resin and hardner down my shirt front for about thirty minutes before mixing. Your procedure will cause you much heart ache - shorten the working time and cause a sticky mess with most any of the finishes.

Gon Fishn

It's rare that any of the popular epoxy finishes develop actual cracks or checks. That little mark at the edge of the guide foot is a stretch mark caused by the movement of the guide in relation to the blank when the blank is flexed - the guide does not want to flex.

Nothing you can do to your finish will cause or eliminate this - the problem isn't coming from the finish. It's an inherent problem that exists because 1. Guides are largely overbuilt for the job they have to do and 2. guide frames are made from materials incorporated in a structure that is just not very flexible.

The way to eliminate these cracks is to design a lighter and more flexible guide frame.

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Certainly making the guide foot more flexible couldn't hurt, but I would still think that overheating the resin to the point that it either over cures, or degrades and becomes brittle, will do more harm than good. Most of the 2 part finishes will remain somewhat flexible under a standard RT cure. A brittle resin is probably more likely to crack and separate when subjected to flexing of either the guide foot or the blank.

No doubt, although I don't flame my finishes and those little stretch/cracks often appear anyway.

The problem I hear from so many guide makers is that you can't put a rigid ring in a flexible frame. Okay, I'll buy that. But, there is another way...

Anyone that has ever seen the old nylon framed Daiwa Dynaflow guides remembers the problem. In order to keep the upper part of the frame from flexing, the entire frame was greatly overbuilt thereby negating the reason for the nylon being used in the first place. However, if you built the lower half the frame from nylon (similar to the material used on Fuji type seats) and then used an upper frame of metal holding the ceramic ring, and then "pinned" the upper frame into the lower nylon portion, you would have a flexible frame with a rigid upper that wouldn't spit out the ring.

More labor would be required as the upper would have to be epoxied into the lower half, or the upper half molded into the lower, but I'm betting that rod builders would flock to such a guide.

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