It's been 10 years since I finished my Tatman boat and it's still going strong. However, the UHMW has seen it's last days as it has become brittle and beaten over time and over a few rocks. I am considering to recoat plywood with epoxy and then have line-x XS-350 applied to the bottom in lieu of replace with UHMW. Does anybody have any experience with line-x in this application and/or any advise?
Jason of Montana Boatworks(much experince building and repairing all manner of small boats) strongly advises against any Linex application to a conventionally framed boat. Personally , if you put the stuff on and than have to repair a frame or so yoiu will never gert the stuff off to do the work.
Just my opionon- but then again I may be full of S--T, cabernay or beer.
Thanks Lawrence. I saw a few blogs indicating as such but don't understand since I also heard he/Jason builds his unframed boats with application of a similar product to line-x over the top of kevlar reinforced bottom. If true I therefore wonder what difference there is in applying line-x over epoxy on a framed boat?????
You should not put the spray on liner over the chine cap. Usually the spray on goes on the bottom and wraps up the side of the boat about four inches. The chine cap is a removable piece that protects the chine of the boat from rocks on the river. Most stitch and glue boats round their chine to deflect energy and minimize damage. This also allows the liner to easily make the transition from bottom to side.
I can't think of a reason that you wouldn't spray on the line-x to the bottom as long as it is on the bottom only. There might be some wear or damage to the edges near the chine as you use the boat but I believe that would be normal. I have not tried Line-x on a boat bottom yet. Some bed liners are sticky on rocks. I've heard that Line-x is not.
I am working on doing some tests on a 1/4 sheet of UHMW that looks the same as has been used for years but is made during it's manufacturing process with a cloth backing. This allows it to be vacuum bagged to the boat bottom rather than screwed. I'm pretty excited about it.
I have this very application on my boat. So far the stuff has been great, and wears unbelievably well. On my boat it comes up the side about 4" as Randy mentioned in his post. If I ever do it again, I will not have it come up over the chine cap. My boat is 30 + years old and only floats on the very benign waters of the South Fork of the Snake, if I hit a rock and bust up the chine cap on that river, I shouldn't be allowed back on the oars. ;)
I am not sure about this Line-X idea. I know that Jason of MBB uses it and he is as good as any builder out there but, when the time comes for what ever reason, hit a rock, trailer damages what ever. That stuff is going to have to come off.
Epoxy is very easy to deal with. A rough sand and we are ready for repair and it's takes no time at all. When factoring in the cost of having someone spray on the Line-X I can't seem to justify the numbers. A layer of kevlar and epoxy seems to make more sense. The comments by others about keeping it off the chine also sound wise.
In working on other boats, kayaks etc which are made of plastic or other materials I always come back to wood/epoxy/fabric. Over time the bottoms get scratched up and epoxy repairs are simple. The Green River in Utah where I spend most of my time doesn't really have all the boat snagging rock others have to deal with so the issue of the slick bottom is not that much of an issue for me. I also feel long term the plastic shoe is more trouble then it's worth. If we could bond it that would be one thing but I don't like the options of surface screws. They are a foot hold for rot.
As for white water boats wood/honeycomb covered with epoxy/(glass/kevlar) are the only way to go. If we put a hole in one the size of a basket ball it won't stop us from getting home.
I have a friend who owns a Montana Boatbuilders boat. It looks to both of us as though the Line-X has a coat of epoxy over it. I presumed that made it even a little tougher, but that the real reason for the epoxy was to provide a smoother surface. My friend has drug his boat over some awfully bony water without damaging the bottom whatsoever. Even at that, I think the Kevlar and epoxy combination would be better for a framed boat with chine caps.
I'm back. I have been doing some additional research and it appears I am reaching a decision point roughly in line with your methodology.
I am leaning towards kevlar for bottom. The questions remaining....
What weight, what weave and how many layers? I would like to do it in one layer say 9oz or 13oz but not sure if that is sufficient. I havn't been able to find anything greater than 13 oz. on the web. any info here would be appreciated.
layup...wrap the chine cap or not? If so wrap with either kevlar tape or wrap the bottom pieces over the chine cap? Epoxy the kevlar to the chine cap or........
I plan on putting new uhmw strips over the chine cap again. I had good experience with them in this application...just not on the bottom. I could possibly wrap the bottom kevlar over the chines but just not epoxy it to the chine cap but rather sandwhich it in between the uhmw chine cap and the oak chine cap. A 'flap' on each side of the bottom kevlar piece in a sense to wrap/sandwhich to the chine cap. By sandwhiching vs. epoxy this would thereby allow the chine cap and chine to be removed at a later date if needed and would not expose cut edges of the kevlar bottom pieces but rather the edges would be exposed on the top of the chine cap sandwhiched accordingly. But not sure about this idea or not but sounds reasonable. I think the challenge with this dry 'flap' concept would be wetting up the bottom but keeping the epoxy cleaned up that pushes out the sides and keeping it off the 'flaps' to allow them to be bent over the chines. The only other question with this is how easily the heavier kevlar fabric would wrap the chine cap in this application? The last option would simply be to not put anything on the chine cap and only kevlar the bottom and may be a be over zelous with the kevlar but having a layer of it over the chine cap sure sounds like good additional protection.
regarding bottom layup, I plan on laying up the kevlar perpindicular to the length of the boat and overlapping each piece on the bottom approximatley 6". This is primarily due to the fact that widest part of bottom is 54" and most all heavier weight fabric is less than 50" and thereby would still have a 2" gap on either side of the bottom to deal with.
I decided on 13oz triaxial Kevlar with a layer of 5 oz fiberglass over that with final two coats of epoxy including some graphite powder. I did end up wrapping the chine cap as I did not want frayed edges exposed on the bottom plus it adds structural integrity to the chine albiet functionally not allowing the chine to be 'repairable'. Over the top of the chine cap wrapped with Kevlar/fiberglass I will put UHMW strips which held up very well in this application before. Below is the buildup....It all sounds good in theory but until I take my first rock I will be a bit nervous since I have 0 experience with this layup in this application....stay tuned. I got everything from raka inc. out of Florida. Great service from Larry/owner and great pricing albiet limited selection.
(1) filled cracks from pull out of screws from previous UHMW on bottom...used expanding gorilla glue
(2) rough sand
(3) two coats epoxy
(4) dry laid 13oz. triaxial Kevlar (you could go heavier but couldn't readily find plus taking it around the chine cap with anything heavier would be a big challenge)
(5) two coats epoxy
(6) 5 oz fiberglass...just finished yesterday
(7) 2 coats epoxy with graphite powder.
I am interested in possible boating/fishing in Utah. I may be staying within Sundance and interested in as much detail as possible regarding the Green. I would be traveling to Utah with boat in tow! Thanks so much.
Well, Darrell your are in for a surprise if you are staying at Sundance. I live about 20 miles from Sundance which is right on the Provo River which has some of the finest brown trout in the country. The only problem is that is sees a lot of fishing pressure.
As you go up the river road and continue past Deer Creek reservoir the Upper Provo river above Heber City is also great fishing. 25 inch browns are landed on the upper Provo. Make a right turn at Heber City and in 15 miles you come to Strawberry reservoir a large body of water which has large Bear Lake cut throat, 20 inches plus, I have seen 30 inch trout taken out of Strawberry. Continue on to Duchesne Utah and to the left is the North slope of the Uinta mountains and the Yellowstone, Uinta and Whiterocks rivers. Good brook and rainbow fishing. Head on to Vernal and then to the Green below Flaming George. As for the Green a 29 pound brown was landed by the boat ramp below the dam Christmas eve about 20 years ago. Above the dam lake trout over 50 pounds have been caught.
To add one other little stream that is great fun along Larry's route, Currant Creek. As you come over the hill from Strawberry and down towards the Duchesne about 4 -6 miles after the reservoir is our of sight, you cross over a little creek that flows from the north side of the highway (which will be your left hand side). Right after that there is a little gas station, turn left at the gas station and follow the creek up stream for about 3 miles to get tot the better stretches. It is a small stream but has brown's and cutties up to 20 inches all over the place. Wonderful dry fly action especially if you hit the Caddis hatch(s) late in the day.