Tom (Kirkman), I've got (what I think) is all of the back issues of RodMaker Magazine related to building carbon sleeved expanding urethane foam grips. But I've got a question I can't seem to find the answer to. What grade of Carbon Sleeve is best suited to grip making? I'm inclined to go for the 12k (heavy) Carbon Sleeves from Soller Composites. A little experienced recommendation would be appreciated.

Anyone else? Please offer your opinions.

I think you will find the 12k very hard to conform to any sharp curves, such as over the ends of grips. I personally use the light weight on fly rod grips.

Thanks Phil, I didn't think of that. I did find the part of Tom's initial article that stated it's unnecessary to use anything more than the thinnest sleeving. I also have the article on using shrink tubing to assist in conforming the sleeving. I also have all the vacuum equipment and I think I can rig up a way to use vacuum to force the material to conform. I don't use intricate shapes on my grips though. I prefer them simple and minimal.

What kind of rod are you making? Heavy and even Medium is definitely overkill for almost anything but offshore butts.

All you are doing is adding resin and weight with the heavier sleeving.

Actually, the only sleeves that come in usable sizes are the 3k and the 12k (standard and heavy). North Fork Composites uses a base layer of unidirectional and then a sleeve over the top of that. So, they make sure the strength is there, regardless of the size of the grip. I've purchased approximately 10 of them and they are nicely built. So, I'm looking at other options. Plus I need them built differently so I'm making my own. Given the degradation of the finest cork I'm opting to make all rear grips, on the spinning rods I build, of Carbon Fiber. I'm so disappointed with the available cork today. I bought 4, 5 star grade, packs of 100 cork rings and am so disappointed with what's available today. 25 years ago I'd have been rejecting the top grades of today. Plus, my cost was still ungodly!

The strength isn't coming from the skin - it comes from the core. The skin simply protects the core.

If you want to the skin to be the area of strength, such as you'd have with a carbon tube, you'll have to increase the weight which tends to defeat the purpose we were going for.

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Tom H.
You will find 12K carbon sleeves over-kill for producing rod grips and difficult to work with as well. 3K is all that is required, will conform much better but plan on using two plies as a single ply may allow the core to show through in spots. While 6K may be an option, two plies of 3K will eliminate any “show-through”. Soller composites has a great selection and is a very good company to deal with.
You may want to reconsider attempting to vacuum bag a cylindrical object such as a rod handle. I have found it almost impossible to avoid creases in the part where the release ply, breather and bag gathers under vacuum. Soller does offer a composite compatible shrink tubing but I have had unsatisfactory results. Consider simply spiral-wrapping the handle with 0.5in wide 1-2mil plastic. You can squeeze out 80% of the excess epoxy achieved by vacuum bagging under 27in/Hg. The clear coat applied later will cover/hide the step created by the overlapping plastic strips.
I must have misinterpreted Tom Ks reply. The strength and stiffness of any composite sandwich structure, be it rod handles, race car parts or aerospace applications, is solely due to the rigid fabric skins which are separated by the pliable foam core. Basically, the thicker the core, the stiffer the laminate will be. With only an outside skin, composite rod handles are more cosmetic than structural, although that single outside skin, with its enlarged OD due to the foam core, will still add a tremendous amount of stiffness to that section of the rod.

Mark Talmo
FISHING IS NOT AN ESCAPE FROM LIFE BUT RATHER A DEEPER IMMERSION INTO IT!!! BUILDING YOUR OWN SIMPLY ENHANCES THE EXPERIENCE.

The foam core isn't exactly "pliable." It's very rigid which is where any gain in sensitivity over other grips made from cork, EVA, etc., results from. I think some people hear the word foam and conjure the image of an EVA type foam. These isn't that type of "foam."

To hide the core from showing through, make sure you use a large enough carbon skin. You don't want to have to stretch the skin over the core, rather it should slide easily and when compressed a bit will easily hide the core. It is also possible to purchase the foam in darker colors, or tint it that way, so any possible show-through isn't easily seen against the similarly colored carbon skin.

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Well, the strength has to be coming from the skin, otherwise, if the cured carbon fiber wasn't providing much strength it could be compressed onto the foam core. Enough "compressions would compress the foam and eventually create a space between the two causing delamination. So, obviously they are both contributing to the strength of the end product. Below is the video that North Fork put together on their Carbon Sleeve Grip. This is where I've learned what I know about them.

[www.facebook.com]

Once you go watch it maybe there would be more to discuss. I'm using the 8lb foam from US Composites. I've been doing business with them for over 10 years now so I know how great their products, prices and services are. Anyway, I had General Plastics send me their core pack so I have blocks of each of the foam densities. There's no doubt that 7lb is the softest we could get by with. According to the North Fork video, considerable strength is provided by the Carbon Skin on the core. So, I'm going to disagree with the idea that considerable strength is not provided by the Carbon skin. If it didn't, you'd need at least a 10lb foam to provide it.

Also, there is this video from Soller on how to use vacuum to constrict the skin to the substrate (I'll be using this method); [www.youtube.com]

Then there is this one from Soller on how to use shrink tubing; [www.youtube.com]

By the way, I've found a 4oz unidirectional carbon on the Soller site which I'm going to buy and try it the way North Fork does it. I'll be using the Soller 3k sleeve and doing it with my vacuum system. The unidirectional is so light I don't think it will adversely affect the final weight of the grip (the North Fork Grips are extremely light). It just wraps around the flat, not around the "corners" of the grip. Though at 4 oz it's conformability would be very good.

Cannot understand core showing through the carbon fiber weave! I have made 100's of carbon fiber grips with the light weight skin, never even a hint of show through. Using two layers of skin appears to be solving a problem that should not be there in the first place.. Using the correct diameter sleeve (DO NOT OVERSIZE), allows a tight fit when constricted without any visible gaps.

Using heat shrink film tubing as discussed in prior articles works quite well without ridges or lumps. One can also do without the film by smoothing the outer epoxy coats with a gloved finger. This process was developed by J. P. Timberlake

As the co-inventor of these grips (along with Andy Dear), I can tell you the main structural component of the grip is the core. We even attempted to negate using the carbon skin at all but needed something to protect the core. We even made a few sans the skin altogether in order to keep the weight down as low as possible. But eventually fell back on the thin carbon skin to protect the core.

Two layers of skin also tends to create a grip that is heavier than the same grip would be in cork. And thus, no reason to make the grip to begin with unless you're just going for looks. We were going for the lightest, most rigid grip we could get. We found the best all around foam density to be 8lbs. Others have used 6 and even 4 and gotten satisfactory results for their particular purposes.

One other thing that needs to be clarified - the North Fork video gives credit for these grips to someone other than Andy Dear and myself. Andy and I invented these way back in late 2005. By 2006 they were in use and the first articles on how to make them appeared in RodMaker in 2007. Gary Loomis was shown these grips by myself at an ICRBE way back when we were still in High Point. l Jackson, who was working for North Fork some time later and trying to develop similar handles for North Fork, kept me on the phone for hours a time, picking my brain about various ways to make them. Not a big deal, but if we're going back to the actual inventors of the foam-core/carbon-skinned grip type, it was Andy and myself.

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Edited 1 time(s). Last edit at 10/15/2018 12:43PM by Tom Kirkman.

Tom, what size 3k sleeving do you buy? Maybe 3/4" or 1"?

It depends on the size of the core you're skinning. I like the ID of the skin to be about the same or perhaps barely undersize to the maximum OD of the core. If you have to stretch or open the weave of the skin to get it over the core and end up with the core showing through, your skin is too small.

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Tom, I know you and Andy created them and I appreciate the work you've put into your creation. Just look at your publications, it's very clear. I don't recall Alex crediting anyone in the video but there's a lot of garbage in that video that I skip through. So, I'm sorry you're offended by whatever he said.

Could you please advise me on what size sleeving to order? edited to add; oops, I see you answered the question. But, given that most grips are between 3/4" to 1.25" it looks like the 1" should be about the best. I'm not ordering a bunch of sizes until I feel comfortable making them. I'm not using these for anything except rear grips (spinning) for now.

An example would be the fly grip you show in Volume 11 - Issue #4 on Shrink Fitting Carbon Skins. The thinnest part of that grip is what 3/4"...7/8ths and then the thickest part...1.1"? What size sleeving did you use?



Edited 2 time(s). Last edit at 10/15/2018 01:30PM by Tom Harder.

I build only fly rod grips and use 1" sleeving exclusively. I works well on all fly rod grip shapes. And, as I mentioned earlier, no core show through.

Thanks Phil, I appreciate that. I'm in Minnesota and we have a few Walleye fishermen :-). So, I build a lot of Spinning Rods. Given most fish are below 10bs I build rear grips considerably shorter than production rods. They're about 6-7" and I want to build them with a composite rear grip instead of cork. I'm just so fed up with the cost/quality of cork that I'm building them of graphite over foam from now on. I'm willing to say that I think almost all rear grips are too long. They also don't have to be thick either. So much more comfortable to use in your hand all day long.

The other half of my rod building is split between fly rods and Musky rods. Those guys are really committed. Then there are the two handers. Switch rods (and Spey Rods) are becoming a bigger and bigger part of my business. As a result, I build few rods with large grips.



Edited 1 time(s). Last edit at 10/15/2018 01:59PM by Tom Harder.

I stock mostly 1 inch skins, but my grips are typically a little larger in OD than what most people are using. I would say that whatever your grip's greatest OD is, use a skin that is no larger than that, but only the closest size smaller. If that makes any sense.

The NF video did credit the grips to another builder. Not offended, just making clarification. No problem.

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That makes perfect sense Tom...thank you. I ordered 1". I also ordered the 4oz unidirectional. It's .006" thick. It was inexpensive and I want to try it. They say it's super high quality.

Still, North Fork should do their research properly and credit you and Andy. I did know that anyway.

I'm also strongly considering a Vinyl Ester resin and also a sprayed Vinyl Ester Clear Gelcoat (Duratec) finish coat. I'm really looking for the hardness and durability that goes with gelcoats. I have not found epoxies or urethanes as durable.



Edited 1 time(s). Last edit at 10/15/2018 05:44PM by Tom Harder.

I have also built 100's of these grips for my rod business and other builders and find the light sleeving works great and does not wear through. This is from large trolling rods to ultra lights. Diameter of sleeving is more important. I get the 1" and 1.25 for my builds and that has covered all the sizes I have needed so far. I use 6 lb. foam that I mix myself. All you have to do is get the 4 and 8 lb varieties and mix equal parts of Part A together. Part B is universal and works on all densities. I make enough of these handles that it works for me cost wise. If I were just starting I would get just the 8 lb. The 6 gives me a grip that is just slightly lighter or equal to cork in weight. the 8 lb makes a grip just slightly heavier. I used to tint my foam but have gone away from it. I instead now spray paint my cream cores black or whatever color I happen to be trying to match. I find that it seems to seal the foam ( I know the foam is not supposed to be able to absorb moisture ) and makes the wet out nicer and seems to take less epoxy to get good results. I have tried other types and thicknesses and have found them to be difficult to work with. The only sleeving I now use is the light straight carbon fiber and the carbon/natural fiberglass sleeving. the CF/ fiberglass lets you paint the core and have the color show through where the fiberglass strands are.