I revisited some pull testing that I said I'd do for Chris, and anybody else who is curious about the strength of wraps.

I wrapped up a bunch of single foot guides with A thread using straight wraps, block wraps and forhan wraps, finishing in sets of three with Flex Coat CP and Permagloss, Flex Coat CP and Threadmaster, and just Threadmaster. I used sections of old blanks laying around that were pretty close to identical with not too much taper.

Average pull force required to pull the guides from the wraps were:

Straight wraps
Bare thread - 4 lbs
CP and TM - 29 lbs
TM w/o CP - 31 lbs
CP and PG - Over 50 lbs, assumed at 75 lbs minimum

HT metallics with TM and no CP - 27 lbs

Blocking wraps
Bare thread - 5 lbs
CP and TM - 30 lbs
TM w/o CP - 31 lbs
CP and PG - Over 50 lbs, assumed at 75 lbs minimum

Forhan wraps
Bare thread - 11 lbs
CP and TM - 46 lbs
TM w/o CP - 48 lbs
CP and PG - Over 50 lbs, assumed at 75 lbs minimum

HT metallic with TM and no CP - 31 lbs

Boring details are below:

I used 42 HFB size 7's for the bulk (cuz that's what I had the most of to make things consistent), 12 BLG size 8's (just cuz I had some). used A thread only because that's all I use, so it's all I have around, FC CP cuz that's generally the CP I use, and TM cuz I haven't pull tested with it before. Guides were unprepped "out of the box" for consistency. All wraps were done with identical tie in's and tie offs, with no packing, just letting what is my normal thread tension lay naturally. Pulls were done with a digital scale with a max load of 50 lbs at as close to identical angles and pull rates as possible. There were no notable differences between the HFB's and BLG's so the measurements were combined for the averages, which were all rounded to the nearest pound. I didn't use double foots because I only have small ones that I do not believe are even close to substantial enough to matter.

PG wraps couldn't be measured as the scale maxed out. It took a lot of effort to pull them free, and some are still wrapped though the ceramics were pulled out of the frames and on a couple of them, I observed noises that I can only attribute to the blanks being compromised, though the guides remain attached. Best estimate on the ones that did pull free were at least using 75 lbs.

Any finish will be far more than strong enough to hold a guide on, no matter what the abuse you give it. IF you want the strongest of all, use permagloss.

Mick..

That is unreal! Thanks for taking time in doing the test as this will change some things for me in the future! My hat is off to ya Mick..
Paul

Mick,
How many coats of PG did you apply?
Did you fill in the tunnels? If so, how many applications?
Than you very much for the info. I have been using PG for those rods that I am using ceramics all the way, to keep the weight down.
Also surprised that CP had little effect. Which product did you use?
Herb

Mick,
I guess there are no tunnels on SF guides.
Herb

Mick,
Thank you. The results of your measurements should help put a lot of the discussions and speculations on this subject to rest. I do have a question though and that is at what angle relative to the rod did you pull?

Great Mick, Thanks!! Hopefull, you helped put the long held myth that CP wraps are weak, to rest!!!!!!!!!!!!!!!


Mike (Southgate, MI)
If I don't want to, I don't have to and nobody can make me (except my wife) cuz I'm RETIRED!!

Most noteworthy is the small difference between strength in wraps made with and without color preserver. This is the same thing I found when doing the pull tests for our article on color preserver some years ago. Your differences were even smaller than mine. I'd like to think this would put to rest the idea that wraps made with color preserver are somehow "weak."

Note that the Forhan wrap adds over 20% to the holding power of the same wraps made without it.

PermaGloss is a terribly strong product, in more ways than one. It's properties also make it the ideal product for use on threadless guide wraps. But... its guide holding strength when used with and without thread are different.


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

Herb,

Yes there are the same tunnels on SF guides as on DF guides, just half as many per guide. Filling the tunnels adds strength against lateral forces, but I'm not sure it would add much to overall direct pull-out strength. Maybe. I just haven't done any direct comparisons to be able to say for sure.

Mick would have to advise if he filled the tunnels on his test wraps.

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

Thanks for taking the time to do an in depth study of this situation.

One thing that stands out besides putting the old "Use of CP significantly weakens a wrap" contraversy to rest once and for all; is the obvious fact that, bare wraps are significantly inhanced by the use of a thread epoxy, not that the actual fishing loads will be applied exactly at the same angles, but it appears to me it does a little bit more than merely protect the threads from the elements, it becomes an intrical part of developing the full strength of this threaded load bearing process. Which thread epoxy is used also has a notable variance as least with regard to more standard 2 part thread epoxies and one part Permagloss. I have to think that bare thread allows the guide to slip out rather than allowing each wrap to combine and work as one unit with the increased adhesion necessary to prevent premature failure.

Excemplary Work, thanks again for the follow up.

Ammended portion

Tom, later informs me that some thread epoxy (other than Permagloss which does actually bond) merely does not allow the thread as a unit to stretch or twist free which in all the insidences was the cause of failure, no actual thread was severed, the guide pulled loose. Denying stretch through the use of thread epoxies allowed for 6X greater holding power before slipage occurred



Edited 1 time(s). Last edit at 12/23/2006 08:29AM by Chris Karp.

Mostly, the epoxy or other finish stops the thread from stretching and allowing the guide to create room to slip out. It doesn't really bond the guide to the blank, although in the case of PermaGloss, that's exactly what it does - bonds.

..........

Mick,

One question that begs asking! Chris mentioned "but it appears to me it does a little bit more than merely protect the threads from the elements, it becomes an intrical part of developing the full strength of this threaded load bearing process." Did the threads on ANY of the wraps actually break, stretch, etc.?? Was the force applied straight down or on an angle? I'm guessing NO!

Mike (Southgate, MI)
If I don't want to, I don't have to and nobody can make me (except my wife) cuz I'm RETIRED!!

Herb, I used 5 coats of PG. It was enough to just barely be able to see/feel the threads. As far as tunnels being filled, I didn't actually fill them in a manner that I would normally do on larger guides. For small guides like these, they were filled by letting the blanks dry with the guides down for the most part, letting gravity do the work. I did the wraps and finishing the same way that I do when building, nothing extra, nothing less.

Emory, I came up with a rather complicated formula to figure out the most accurate method of grabbing a number out of the air, and came up with an upward angle of about 30 degrees, pulling the guides in line with and toward the tip. It seemed to be a good angle that wouldn't be trying to bend the guides down against the blanks or be trying to pull them through the wraps, rather than just out. No real scientific reason other than "with those guides, it just felt about right". The rate of pull was 1 to 2 pounds per second, chosen because it was measurable and easily repeated for consistency, and slow enough to easily read a fairly accurate number at failure.

The last time I played around with this, I seem to remember slightly lower readings across the board with epoxy as well as a bit more spread between CP and non-CP use. Not much, but a little. Differences between epoxy types, amount of CP used, amount of epoxy "web" between the leg and blank, thread packing and thread tension can all be factors, as well as the guide type, whether it was prepped or not, and even all the little things like temp and humidity, thread age, etc. Somebody else duplicating this exact work could easily have different numbers, but overall I think that the ratios between the types will be very similar across the board.

As far as breakage, the only thread failures were the 3 forhan threads on each guide (which would obviously have to break) All other wraps are as pretty as you please, they just don't have guides in them. I didn't want to try factoring in thread strength, just basic holding strength. As Tom mentioned, anybody who has stripped wraps of each will know that epoxy can be peeled away with little effort but permagloss is a royal PITA to strip off a blank. The main reason that some of the permaglossed guides are still attached to the blanks is because as I neared the end, I was plain wore out.

I was curious about the doubles that I do have though and just wrapped and pulled a few HLC size 10s with no finish. They deformed and pulled out of the A nylon at an average high reading of 22 pounds, and deformed and pulled out of HT metallic at an average high reading of 18 pounds. None of the threads broke, but it's gonna take some work to get the guides in usable form again. I think this helps in showing that thread itself makes for some very strong wraps.

I agree with Mike...it seems the finish does more than simply protecting the thread from the elements. Based on the minimum amounts of all three tests the average pressure to pull free went up by almost six (6) times with epoxy vs. bare thread.

Jay

Jay,

What I meant is that I don't think that the finish adds any strength to the thread. As Mick said, the thread didn't break, even on the guides that had bare thread. CP prevents the finish from penetrating to the guide or blank also. I think that finish and/or CP protects the thread and while sealing it, also prevents the pulling/torque, etc from stretching the thread and allowing the guide to slide out (without damaging the thread, BTW)

Mike (Southgate, MI)
If I don't want to, I don't have to and nobody can make me (except my wife) cuz I'm RETIRED!!



Edited 1 time(s). Last edit at 12/22/2006 06:24PM by Mike Barkley.

gotcha

understood

Jay:

I am the one who 1st said thread epoxy adds strength. (Mike was asking about a point of clairification regarding thread failure) I noterd that thread epoxy is more beneficial than merely to protect wraps from the elements, but it does not add strength, thread epoxy stabilizses the tensile chartisatics of the thread making it preform more as a unit and not stretch which in this instance amounts to more achievable strength in the unified structure as the threads themselves never fail. BUT this is not to say that thread epoxy does not add significantly to the holding power of the thread and in actuality it is much more than a mere sealant, (which is often said to be all it does on this site) thread epoxy in effect allows threads to exhibit a greater percentage of there maximum potential. 6X's greater all things being equal which they are not.