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Ben_D

Cracked Epoxy
« on: January 20, 2014, 11:05:40 AM »
Hi all,

The epoxy on the two stripping guides on my newly built Method 790 is showing some signs of cracks, this is something that has happened on every single rod I have owned that has been really made to bend.  I built with standard Flexcoat which, to the best of my knowledge is what the manufacturers of most rods I have owned also use.

Is there anything I can do to prevent this during the builds or, is there another finish that is less prone to this?  I'm really not sure what is going on as the dried finish on the inside of mixing pots I have (from a god few months ago) can be peeled off and bent / folded and it does not snap or crack.

Cheers

Ben

Rob Brownfield

Re: Cracked Epoxy
« Reply #1 on: January 20, 2014, 13:11:41 PM »
Yes, would i be correct in saying the crack is in line with the tip of the guide foot?

If so I would hazard to guess that you have a few millimetres of thread up the blank from it?

If that is correct, then in the future, only have three turns of thread before it starts to climb up the foot. When adding epoxy, only overlap onto the blank a fraction, no more than 1mm.

That should sort your problem as the flexcote should be able to bend more evenly.

As you already have noted, the flexcote does remain flexible, but the guide foot acts as a stress point. It's a well known problem on big casting sea and coarse rods butt rings.

If, however, it is not cracking at this point, but further up the foot, then it may be down to the gap between thread and blank being a void rather than filled with epoxy.

Hope that puts you on the right path...
Ok, I admit it, I quite like this salmon fishing lark....

Ben_D

Re: Cracked Epoxy
« Reply #2 on: January 20, 2014, 23:19:19 PM »
Thanks Rob,

The crack is in the epoxy running from the base of the guide in line with the ring from one end of the foot to the other (front to back).  I only tend to put three or so turns of thread onto the blank before I get onto the guide foot to minimise the area I am going to epoxy and allow minimal on the blank at the end of the wrap, may save a few micrograms over the entire rod  :z4

I am using rust Gudebrod thread over the red blank so any bubbles /  voids between the guide foot, whipping and blank could be seen, there are none and all is filled well with epoxy.

Could it be over tight thread?

Cheers

Ben

Rob Brownfield

Re: Cracked Epoxy
« Reply #3 on: January 21, 2014, 07:40:36 AM »
Hang on...so its across the top of the foot, length ways?

Only evey had that on old rods...20+ years old! And then it tends to brown and then flake rather than crack..

Silly question, when you whip and burnish the thread, are your hands clean? Epoxy does not like grease, oil, silicon or general sweaty fingers. I am wondering if you are rubbing the top of the thread to get the whipping nice and close.

Have you got that blue metalic thread wrapped around the whipping? If so, this might be the cause as they use silicon to lubricate the thread for machine embroidery on some threads.

I cannot see how tight thread would cause the epoxy to crack. Loose yes, as the guide could move, but not tight.

Sounds like there is only one thing for it...off with the epoxy and on with shrink wrap tubing! ;)
Ok, I admit it, I quite like this salmon fishing lark....

Ben_D

Re: Cracked Epoxy
« Reply #4 on: January 21, 2014, 07:48:18 AM »
Yup, down the length of the guide Rob.  I get it on all the rods I use for distance work

Cheers

Ben

Rob Brownfield

Re: Cracked Epoxy
« Reply #5 on: January 21, 2014, 07:56:42 AM »
Yup, down the length of the guide Rob.  I get it on all the rods I use for distance work

Only on the double legged guides?
Ok, I admit it, I quite like this salmon fishing lark....

Ben_D

Re: Cracked Epoxy
« Reply #6 on: January 21, 2014, 09:59:30 AM »
Usually only on the stripping guides Rob, but my Access 912 was sent back to be re whipped because every whipping had cracked up but that rod did see some serious abuse.

Cheers

Ben

Rob Brownfield

Re: Cracked Epoxy
« Reply #7 on: January 21, 2014, 10:29:26 AM »
Ok...well, one of the issues with titanium guides is that they do not flex compared to "normal" guides and thus put pressure on the whipping on "bendy" rods". But that would not explain the Access.

Only thing I can think of is that you are a ham fisted caster with little skill and thus twisting the blank due to crap tracking :z4 :z4 :z4

A quick search on the FlexCote website states that cracking may occur if not enough hardner is used (Hardner is what makes if flexible...as they say in the US...go figue!)

I have heard good things about Threadmaster epoxy. Even their advert says "Absolutely will not crack". Maybe worth a punt, available from G'nB

Ok, I admit it, I quite like this salmon fishing lark....

Rob Brownfield

Re: Cracked Epoxy
« Reply #8 on: January 21, 2014, 10:53:35 AM »
Forgot to say, I have moved onto ProKote, not used it yet..but SOON! Meant to be the bees kneez...but who knows longterm?

I did a quick search on one of the rod building forms and there is a suggestion of slipping thread causing cracking/lifting on the foot itself. Sort of makes sense. As the rod flexes the thread, if whipped with uneven or over tension will want to even out that tension. The area that will show this up is at the edges of the reel foot, lengthways.

Ok, I admit it, I quite like this salmon fishing lark....

Ben_D

Re: Cracked Epoxy
« Reply #9 on: January 21, 2014, 15:18:49 PM »
Using syringes to mix so that should not be an issue, the crack is not along the edge of the foot it is right down the middle of it!


Cheers

Ben

Rob Brownfield

Re: Cracked Epoxy
« Reply #10 on: January 21, 2014, 15:44:44 PM »
In that case, I give in!.. :z8

Buy an "interline" blank and then you wont need guides.. :X2
Ok, I admit it, I quite like this salmon fishing lark....

 




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