I recently sent a fly rod I built back to the blank manufacturer to have a broken tip section replaced and got the rod back last week.Upon looking at the new tip section a bit closer I noticed that the wall thickness of the female ferrule was not the same all the way around the opening.When looking in to the female ferrule opening it is quite noticeable to the naked eye(no need of a magnifier) as one side of the blank is very thin and the other is considerably thicker.I've built on several of these blanks before and they are very light weight,high modulus and tend to have fairly thin walls but on all my other blanks the wall thickness has always been pretty uniform.

It cost me quite a bit to get this new tip section(had to pay for the tip as well as shipping the full rod there and back) and these blanks are long discontinued so sending this tip section back for another one would be very difficult.I certainly don't want to have to send off my whole rod again and I'm not even sure if there are any more tip sections left for warranty replacements of this particular model.

Anyways,my question is how concerned should I be about the difference in blank thickness around the female ferrule opening?

Will the difference in blank thickness here increase the chance of the blank failing at the ferrule?

Also,I normally build on the straightest axis and was wondering if I should still do so with this particular blank section and not worry about the difference in wall thickness at the female ferrule opening?

Does it matter how I wrap the ferrule or align the blank in regards to the wall thickness at the ferrule opening?In other words would there be any difference in ferrule strength and long term reliability by having either the thinner half(using the wall thickness at the ferrule opening as a reference) of the blank face down in line with the guides or facing the opposite direction so the thicker half of the blank is aligned with the guides?

This is the first time I've noticed a real difference(one that doesn't require magnifying glass to see it) in wall thickness at a ferrule opening so I'm not sure how big a deal it really is.If it is a definite issue that could result in a failure I would like to minimize the possibility of this happening.

Wall thickness is never perfectly uniform. Sometimes this is more apparent in some blanks than others. It is not generally a problem, although without a photo I really can't tell you one way or the other if you're staring at a potential problem or not.

There is always a chance that the person who stripped the cellophane and sanded the blank went too far on one side. Abot the only thing you can do would be to call the manufacturer and get their thoughts on your situation. If they're not longer in business, you're just going to have to try things for yourself.


................

Is the thin part thinner then normal? Or the thick part thicker?
If it is no thinner then what is normal, I would think you should be OK and I would build on the straightest axes.
If it is thinner I would do as Mr. Kirkman suggests and call the manufacturer

I am sitting here reading this and wondering what I would do if I were in your situation. So I am going to throw this idea out there and see what kind of bites I can get.

If I couldn't get any satisfaction from the mfg, whether it be availability or cost issue, I would try to answer Steve's question first, is the thin area thinner than normal or is the thick area thicker than normal. How far back the ferrule does this thin area go, 1/4 in, 1/2 in more than an inch ? That could be determined with a metal straight edge from the outside or possibly with a caliper.
I would consider building up the thin area with a 2000 lb epoxy and dressing it down to an even wall thickness and wrapping it with matching thread.
The root cause probably lies with the person that removed the cellophane and ground the blank just as Tom stated. He had to sneeze and he stopped rotating the blank while against the grinding wheel, probably as simple as that !

J.B.Hunt
Bowling Green, KY

What blank ? where did you get it ? Cheap ??? Did you get it from any sponsors on the left ?? Is this an @#$%& thing ???????

Bill - willierods.com

Thanks for the feedback everyone.I just re checked the blank and compared it to others I have and I don't think it will be an issue.

I don't want to say the name of the manufacturer(not a sponsor,excellent blank and not an @#$%& off blank) as this is a blank that was discontinued a while ago and I should probably consider myself lucky just to find an extra tip section for it.

The blank is a 4wt and I have another identical 4wt model,as well as a 5wt for comparisons.They all have pretty thin walls and are very light weight.Under magnification the difference in wall thickness was not as great as I originally thought.The thinnest part of the blank is actually thicker than I originally thought and is a tiny bit thicker than the other identical 4wt blank I have,in fact it is closer to that of the 5wt so I think structurally it should be just fine(if it wasn't I doubt the manufacturer would have sent it to me in the first place).I did want to double check and see if it matters how I align it though.

It's a little hard to describe but if you were to look in to the hole of the female ferrule and cut the hole in to 2 halves,with one half having a little thicker wall than the other half,would it make any difference in performance,power or ferrule durability if the thicker half of the blank faced up or down(in line with the guides)?

Tony -
I don' t see any way to answer your last questions

( "It's a little hard to describe but if you were to look in to the hole of the female ferrule and cut the hole in to 2 halves,with one half having a little thicker wall than the other half,would it make any difference in performance,power or ferrule durability if the thicker half of the blank faced up or down(in line with the guides)? " )

without cutting the entire blank in half since there is likely no way to tell how far up the blank the "unevenness" of the wall diameter continues - that is: Is it only at the ferrule or how far toward the tip does it extend. Best bet is likely to wrap the ferrule section and do a simple spine finder test (stress it and find the strong/weak side). Then you are dealing with the old/continuing dispute over "spine" and it's usage (advantages/disadvantages). Since you've determined that there should be no issue with a failure at the ferrule I'd keep it simple and build on the straightest axis

Good points Ken.I didn't really think about how far up the blank it may or may not go.

I think I'll probably just align it with the straightest axis and forget about it(no point in over thinking and worrying about something that probably isn't going to be an issue).