Has anyone used sheet Kevlar instead of carbontex (or similar). It is claimed to be superior in terms of friction co-efficient. It is also claimed to wear less. Both of itself and to the mating surface. Temperature tolerance is similar to carbonfibre. If all of this is true it should be possible to get the same drag with less applied pressure! That would indeed be good news for lever drag owners ;D
The material can only be purchased ex factory in the UK - ie I would have to commit some serious money to this project. This is why I ask the question - has someone already tried it?
Give it a try and report back with your results.
http://www.cstsales.com/aramid_fabric.html
http://www.trickconcepts.com/Kevlar-Sheet-18-3mm-Thick-P1819.aspx?gclid=CNPOn-OwtLkCFUXhQgodxgUANw
http://www.hobbyking.com/hobbyking/store/__10756__3k_carbon_fiber_and_kevlar_29_cloth_180g_m2_1mtr_.html
(http://firebytrickconcepts.com/images/stories/product-photos/HHS-product-photos/hose-pipe-coverings/tape/1_16-kevlar/all-1_16-kevlar-tape+300.jpg)
http://en.wikipedia.org/wiki/Kevlar#Brakes
"Brakes
The chopped fiber has been used as a replacement for asbestos in brake pads. Dust produced from asbestos brakes is toxic, while aramids are a benign substitute"
It would seem to me that Kevlar is too flexible to be used as a drag, or if it is sandwiched between metal it will not flex. Just thinking out loud. Dominick
I guess you could use Aramid Paper for drags. It's commonly used for electrical insulation. I used to have a bunch laying around, and now...who knows. I many need to find it and try it out.
http://alantani.com/index.php?topic=7909.0
Quote from: Tiddlerbasher on September 05, 2013, 10:35:36 AM
It is claimed to be superior in terms of friction co-efficient. It is also claimed to wear less. Both of itself and to the mating surface. Temperature tolerance is similar to carbonfibre. If all of this is true...
Well, partly. Not the bit about temperature though, although aramid is adequately resistant to high enough temperatures for reel drags.
Quote from: Bryan Young on September 05, 2013, 05:05:31 PM
I guess you could use Aramid paper for drags. It's commonly used for electrical insulation. I used to have a bunch laying around, and now...who knows. I many need to find it and try it out.
Good thinking. It is a very interesting material. But, i tried using it as a friction material, and no... It was just not useable. I don't recall the specifics, but no... That's all.
.
Quote from: Pescachaser on September 05, 2013, 04:36:21 PM
It would seem to me that Kevlar is too flexible to be used as a drag, or if it is sandwiched between metal it will not flex. Just thinking out loud. Dominick
I would glue it to the metal washers.
daiwa used red kevlar in some of their reels. it was horrible......... :-\
The Kevlar I intend to try (a free sample is on its way to me ;D) is not a soft sheet. It is a semi flexible material. It has been designed specifically for braking applications.
Technical info can be found here:
http://www.frictiontechnology.co.uk/contents/en-uk/d44.html
The product is FTL180. PDF now attached to this.
I have spoken with the people and single 300x300mm sheets (that's a lot of washers), .5 to several mm thick, can be supplied. Cost £29.60 excluding shipping & tax. So not as expensive as I orginally thought and substantially cheaper than a similar sheet of CF.!
The material can be operated continuously at 250C (482F), intermittently @ 350C (662F). If a reel drag gets that hot I think I would have other concerns :o Coefficient of friction remains constant @.58 to well over 250C (carbon fibre friction material is typically .45-.48, and can fade noticeably at these temperatures). This would appear to suggest an improvement of about 25% in terms of friction. My reasoning is - comparing Kevlar to CF - that is either more drag (at a given lever setting) or the same drag with less pressure on the drag system (less force on pinion and spool bearings).
From the spec alone it would seem to be ideal. But the real test will be what is it like to work with. Is it easy to cut or punch. From the test data I've seen it seems to run very smoothly (no mention of start up inertia) and can run with oil/grease or dry.
Back to the reel world ;) I'm in the process of making an adjustable spooling jig (mainly for braid). The jig will use a 75mm diameter friction disc similar to a lever drag reel. With drag settings of 10-35lbs, running for minutes at a time, will test any friction material. This will also also be my test bed for the Kevlar friction sheet (I hope the sample is big enough).
PDF data sheet attached for the technically minded.
Sounds interesting! Keep us posted!
/Karl
You will still need grease. Salt crystallization will occur on anything. There is no avoiding that. Also, it would be interesting to see how the dust buildup affects the kevlar. We all have seen the glazing from CF. I wonder what the kevlar would be like. I wonder with the increased friction coefficient, if there will be more heat generated.
Friction turns kinetic energy to heat (thermal energy). With the same amount of friction (drag) the same amount of heat is produced. If you can get higher drag with the higher coefficient, that will produce more heat. But the higher coefficient in itself won't mean more heat. It just means that you need less force to reach the same level of drag as with a lower coefficient.
Correct me if I'm wrong! I can take it!
:)
/Karl
Karl that is my understanding - at the moment! I won't really know until I test it - still finishing the spooling jig and waiting for the Kevlar sample. Tribology (friction in this case) can turn into 'weird science'. Sometimes all the physics and math goes straight down the pan!
Don't I know it! You just have to read the "Experimenting with the 113H drags" thread to be confused and have your beliefs thrown out the window... You wish you had remembered more from physics in school.
Rem?? something what from where ;D
I'm lazy and it seems like a lot of work. I'll stick to the old adage, "If it ain't broke, don't..."
Quote from: Mandelstam on September 09, 2013, 08:09:39 AM
But the higher coefficient in itself won't mean more heat. It just means that you need less force to reach the same level of drag as with a lower coefficient.
That is technically true, but who here do you think won't horse down on the star in order to get a 30% ratio on bigger braid? Men will be men.
If this works and it is rigid enough to be used as hex washers? Watch out, Alan Tani and his boys are coming to pull down the Empire State Building!!
Ron
I hope it is something better, but in certain applications. In some reels, the higher drag numbers bend spool shafts and frames. Everyone wants bigger drag numbers from a smaller reel. I noticed when I was deckhanding that people would run a high drag and forget the hook's embedment strength. You can pull a lot of hooks from running a high drag, you can break levelwind assemblies, and cause issues with AR bearings (if the reel has them i.e. Calcutta 400s, 965s, bass reels, etc.). I am not saying that it won't work because that wouldn't be the proper mindset of any scientific approach. A hypothesis is one thing, a declaration that the world is not flat is another. The world is flat!
Another critical point that I would like to add is that Kevlar brakes in cars have shown that they are more susceptible to brake fade, they generate a lot of dust, and I would imagine that reel manufacturer's R&D guys have spent a fair bit of time playing with drag materials. Not to say that they always get it right, but they do spend a lot of money and that has to account for some of the things that are found in reel's today. We, here, on this board just pick up the things that they couldn't always foresee. It would be nice to find something that much better than CF. It really would. I'd have no shame in using it. Then again, I might just stick with the CF. The same argument goes for the ceramic bearing hype; there is a point of diminishing returns.
If the kevlar works well, let's say a great amount of heat and metal dust is created by the increase in friction. Would we want to add titanium washers to dissipate the heat faster than steel? I think what it boils down to is creating a new drag system.
Quote from: noyb72 on September 11, 2013, 03:51:35 AM
Quote from: Mandelstam on September 09, 2013, 08:09:39 AM
But the higher coefficient in itself won't mean more heat. It just means that you need less force to reach the same level of drag as with a lower coefficient.
That is technically true, but who here do you think won't horse down on the star in order to get a 30% ratio on bigger braid? Men will be men.
If this works and it is rigid enough to be used as hex washers? Watch out, Alan Tani and his boys are coming to pull down the Empire State Building!!
Ron
:) I hear you. I was just trying to clear things up regarding the coefficient. More drag - more heat, no matter what the coefficient is.
I'm a bit cautiously sceptical to Kevlar myself. Mostly for the reason that if it were o much better than CF we would have known by now... I'd be surprised if someone hasn't tried it out before.
But I'm looking forward to the results and please prove me wrong!
/Karl
Quote from: jonathan.han on September 10, 2013, 11:31:50 PM
I'm lazy and it seems like a lot of work. I'll stick to the old adage, "If it ain't broke, don't..."
With that kind of thinking we would still be using the old asbestos washers.
Quote from: noyb72 on September 11, 2013, 03:51:35 AM
That is technically true, but who here do you think won't horse down on the star in order to get a 30% ratio on bigger braid? Men will be men.
I'm not going to change out my Spectra (mostly 60/65 anyway) or buy new rods so I'll be fishing my reels just slightly higher than factory spec. What I want is a extremely smooth reliable drag.
Asbestos was an inferior drag media. Won't disagree with you there. Kevlar has been used in other types of braking/friction applications in other industries. It does not perform well in high-performance applications.
A new drag system?
Some of us have reels with only half the metal washers and laminated CF washers taking their place...
We here are all about new drag systems!!
WHY HAVEN"T I THOUGHT OF TITANIUM WASHERS???!!!
Ron
A new drag system means creating a completely different mechanism; one that can cool faster than current designs in order to address the issue of heat recovery. I'm not talking about slapping a new set of metal and drag washers. Though after thinking about it some more, titanium washers with fiber backed kevlar drag washers (since Kevlar is a poor choice for rigid applications) might work. But, you'd still need to find someone to produce titanium washers and good luck with that. Titanium happens to be one of the hardest materials to cut, mill, and cast. This makes it very expensive to produce low-volume/prototype units.
Titanium is tough to use as well, I forgot about treated titanium