cloth thickness

Post Reply
User avatar
bowgarguide
TKF 5000 Club
TKF 5000 Club
Posts: 5370
Joined: Mon Jan 15, 2007 7:52 pm

cloth thickness

Post by bowgarguide »

Gerald what is a standard layup for your boats.
I am thinking 4 ounce on the outside on this next boat and 6 ounce on the inside,three coats of graphite on the bottom over the epoxy and cloth.
Ron
User avatar
gerald
TKF 4000 Club
TKF 4000 Club
Posts: 4174
Joined: Thu Jun 12, 2003 10:48 am
Location: Gatesville, tx www.theoldmansboats.com

Re: cloth thickness

Post by gerald »

A standard layup for small paddled craft is 6 oz. e-glass on inside and outside. I would think that would be the way to go if you're going to use e-glass. 4 oz. s-glass is about equal to 6 oz. e-glass in strength with slightly better abrasion resistance. S-glass generally costs twice as much as e-glass for a comparable weight. At our levels of construction there are no other cloths to consider. Well...maybe 3 oz. for a SHOWBOAT!!!

So--I would generally say that the way to go is 6 oz. e-glass inside and out.
User avatar
AyJay
TKF 1000 Club
TKF 1000 Club
Posts: 1827
Joined: Mon Jun 11, 2007 4:26 pm
Location: Spring, TX

Re: cloth thickness

Post by AyJay »

I'm using a mix of 6 oz cloth and 7.5 oz tape. It's not that hard to make 7.5 work where 6 is called for, and it's a bit thicker.
User avatar
Pogo
TKF 3000 Club
TKF 3000 Club
Posts: 3627
Joined: Mon Jul 28, 2003 4:49 pm
Location: League City
Contact:

Re: cloth thickness

Post by Pogo »

Warning: I'm gonna talk about weight again. Gotta aggravate Ron and Gerald though . . . . . . just doin' me dooty as I sees it.

Thing I can't stand about 6 oz plain weave cloth is that it takes too darn much fill coating to make the weave "go away", and epoxy fill coats add a passel of pounds without contributing any strength to speak of -- besides just plain being a lot of work. I suppose there's a "skin thickness" that develops that's good for abrasion purposes, but that isn't useful for where I live and operate. 4 oz cloth "fills out" much quicker, meaning less expensive epoxy expended and less weight gained. If 4 oz s-glass is equivilent to 6 oz e-glass, then I'm a convert . . . and I'm using 4 oz s-glass for the first time in this new OI I'm building, for the inside surfaces.

I've used 3.25 oz "satin weave", or fine weave, cloth on all outside surfaces. Satin weave is best for weight savings 'cuz one fill coat generally does ya, and it is said to be equivilent to 5+ oz plain weave due to the density of fibers. But there are certainly prices to be paid for the enticing points, and the one that you guys will probably object to most is you end up with a thin skin with not-so-hot abrasion resistance properties. But I've doubled my bottom layer along the football and keel for that reason, and added dynel wear strips on the external stems fore and aft. I expect great strength-to-weight things to happen. 8)

And, as always, I'm not suggesting that anyone do as I do. I'm just having my fun playing around with shade tree kayak engineering, and adding my thoughts to the mix for whatever they're worth. So start tearing into it, boys. :D
User avatar
bowgarguide
TKF 5000 Club
TKF 5000 Club
Posts: 5370
Joined: Mon Jan 15, 2007 7:52 pm

Re: cloth thickness

Post by bowgarguide »

Pogo
For the way you use a boat I bet that would work ok.
The only thing I disagree with you on I think you are doing it backwards the heavier cloth should be on the inside.
Every fracture I have seen in a wood boat the inside glass held it together even if the outside was punctured and the wood cracked.
Its the same princaple as the indians backin the front of a bow ,the backside of a bow doesnt have to be backed because it is under compression ,the front needs it because it is under tension ,the same as the hull of a boat when you hit are run up on a sharp rock.
Ron
User avatar
Pogo
TKF 3000 Club
TKF 3000 Club
Posts: 3627
Joined: Mon Jul 28, 2003 4:49 pm
Location: League City
Contact:

Re: cloth thickness

Post by Pogo »

The heavier cloth IS on the inside . . . if we believe 4 oz s-glass is equal to 6 oz e-glass, and 3.25 oz satin weave e-glass is equal to 5 oz plain weave e-glass. Basically, it's 5 oz outside and 6 oz inside. The doubler layer on the bottom was added as abrasion resistance since the satin cloth creates such a thin "skin", and there's little penalty suffered in fill coats.

And while I absolutely agree with your engineering theory, in practice my actual cloth breaches have occurred on the outside 99% of the time. Doesn't make sense, but that's my experience. And again, our respective ops are in two completely different theatres of combat. You're liable to bounce off rocks while carrying heavy loads a lot more'n me.

I've never glassed the entire inside of a S&G hull yet, and have never had a crack in the interior of one yet either. Again, doesn't make sense, but there ya have it.
bowgarguide wrote: For the way you use a boat I bet that would work ok.
Hey, it WILL work okay. 8) :lol:
User avatar
bowgarguide
TKF 5000 Club
TKF 5000 Club
Posts: 5370
Joined: Mon Jan 15, 2007 7:52 pm

Re: cloth thickness

Post by bowgarguide »

Pogo
You have my curiosity up now,what kind of breaches did you have give us some details man :D
Are you saying you just tape the inside of a stitch and glue and never had any damage?
Ron
User avatar
Pogo
TKF 3000 Club
TKF 3000 Club
Posts: 3627
Joined: Mon Jul 28, 2003 4:49 pm
Location: League City
Contact:

Re: cloth thickness

Post by Pogo »

Well now that you got me thinking about it, the breaches have developed on outside curves, alright, and in two places mainly. Near the bow of the boat, about a fifth of the way back, and about at the waterline or a little above it. Probably from my idiot habit of beaching the boat at top speed, whereas I haul butt right at the shore, then do a good layback to raise the bow and see how far I can skid up out of the water. I've never quite got the cockpit to dry land, but I never stop trying. :lol: The other place is aft of the cockpit, where the sides of the hull transition to the rear deck. Probably due to my habit of climbing aboard there to self-rescue "ride-'em-cowboy" style. I often jump out of the boat to swim or whatever in deep water (never let go of the boat or paddle!), then clamber back aboard when ready to get on with my life.

In either case the cracks are usually some 3 or 4 inches long, and usually I tape over 'em or douse 'em with a little 5-minute epoxy, clear fingernail polish, varnish, super glue, or whatever else is handy until I get around to doing a real repair with 'glass patches and 'poxy. I guess my Outer Island gets about a dozen of these kinds of breaches per year. It was done in 6 oz plain weave e-glass inside and out, by the way, and tends to live 24-7 on the racks which doesn't help anything at all. I'm not sure what causes them, but it almost looks like UV and/or weather damage as much as anything. I've never really given them a lot of thought other'n I wish they'd quit happening. The Cormorant gets 'em too, tho' not as often (the boat doesn't get used as often, either), and only on the stripped deck, never on the S&G hull (except where I punched a hole in it fair and square by dropping it on a jack stand). It also sports 6 oz inside and out on the deck.

Other places that go to bare wood are pretty typical high-wear spots, like where I stow a spare paddle, an anchor, where my heels end up in the cockpit, on the stem or stern, places like that. When they develop I just add a glass patch or two or three and jump back in the race.

I inspect the interiors fairly routinely with a bright light and a vanity mirror-on-a-stick affair, but like I said, I've never found anything needing repair yet. Thank goodness for that, too, 'cuz it'd be a tedious PITA to do. I always approach those inspections with dread, and I reckon my luck'll run out sooner or later.

On S&G hulls I fillet and tape the seams inside, give the otherwise bare plywood two good coats of 'poxy, and glass the outside. I got started by reading Chris Kulczyski's stuff, and CLC follows his method also, on a HUGE scale I might add, with utter success. Or at least, I can't recall anyone complaining about failures and I'm sure John Harris would tell 'em to 'glass the inside in the instruction sheets if they did have problems.

The way you guys talk, the Middle Brazos makes the Colorado River in the Grand Canyon look like a sluggish old backwater bayou. :?
User avatar
bowgarguide
TKF 5000 Club
TKF 5000 Club
Posts: 5370
Joined: Mon Jan 15, 2007 7:52 pm

Re: cloth thickness

Post by bowgarguide »

Pogo
Think about what you just typed,no breaks inside and damage outside,your inside glass stopped
it from coming on thrue.
The reason the Brazos is so bad on hulls .lot of fast shallow water with rocks sticking up within 1 inch of surface,and most of the time small rocks the size of you head,gravel bars sand concrete steel in places.
Ron
User avatar
Pogo
TKF 3000 Club
TKF 3000 Club
Posts: 3627
Joined: Mon Jul 28, 2003 4:49 pm
Location: League City
Contact:

Re: cloth thickness

Post by Pogo »

You want me to THINK about what I type?! Aw c' mon, man . . . . . :(
User avatar
gerald
TKF 4000 Club
TKF 4000 Club
Posts: 4174
Joined: Thu Jun 12, 2003 10:48 am
Location: Gatesville, tx www.theoldmansboats.com

Re: cloth thickness

Post by gerald »

Well...I've got to say that the Great Castell River Race on the Llano is the worst I've put any of my boats through....

Most of that was stupidity on my part. I could have made it a lot easier.....

Compared to that the Neches river race will be a walk in the park...
User avatar
bowgarguide
TKF 5000 Club
TKF 5000 Club
Posts: 5370
Joined: Mon Jan 15, 2007 7:52 pm

Re: cloth thickness

Post by bowgarguide »

what i am saying is we agree on the outside giving
ron
User avatar
Pogo
TKF 3000 Club
TKF 3000 Club
Posts: 3627
Joined: Mon Jul 28, 2003 4:49 pm
Location: League City
Contact:

Re: cloth thickness

Post by Pogo »

Forget it, I ain't thinking. You can't make me. :P
Post Reply