Glassing in stringers

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CypressHunter
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Glassing in stringers

Postby CypressHunter » Wed May 31, 2017 8:13 am

I am getting ready to do stringers I found this video on YouTube and got the basic idea

https://m.youtube.com/watch?v=9jHUI0CiYbs

My question is how may layers of glass should I use? My thoughts are use CSM then go over it with 1708 biaxle. Will this be enough or should I go CSM - 1708 - CSM - 1708?
Last edited by CypressHunter on Wed May 31, 2017 11:13 am, edited 1 time in total.
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Deano
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Re: Glossing in stringers

Postby Deano » Wed May 31, 2017 10:26 am

I don't remember what exactly you are working on, or how you intend to use it, but I would go two rounds anyway. Generally, the strength and longevity increase exponentially faster than the weight which is miniscule in the big picture. Obviously there are extremes, from a small race boat to a big blocked barge with a box and big blades. In the later case, doubling that for the engine stand wouldn't be overkill if you're going to beat on it for the long term.

I will stress again his point about 'pickling' the wood with resin before you start. This is especially important to arrive at the end you are after. Also radiusing the top of the stringer will help your cause and is a good idea.

The bigger point that I would make, that was not part of that video, is that you need to laminate the bottom of the stringer to the hull before you ever get to where that guy started with his pseudo stringer screwed to the bottom (which is something you do not want to do). I generally put a layer of thick mat on each of the hull and the stringer bottom, then place and possibly weight the stringers such that they end up parallel and squarely vertical. There are a number of ways to do this; you just want to end up with any and all voids filled between the stringer and the hull while they remain upright. If you are attempting to address a hook in the hull, realize that you will need enough weight to press the hull flat and have it flush against the stringer bottom. Actually, if you are attempting to do this perhaps you should say so and it can be elaborated on a little more. Needless to say if that isn't the case, it isn't an issue.
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CypressHunter
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Re: Glassing in stringers

Postby CypressHunter » Wed May 31, 2017 11:21 am

I need a new front deck and I don't think my stringers are completely gone but I am concerned there is some rot. I want to do a told hull rehab. All four stringers, front deck and hatch, and fix some gouges and scratches on the outside then paint outside and gelcoat inside. I may even just take it to someone and have the do it. No hooks in the hull now and no hop.

I was planning on using a resin peanut butter mister to "glue" it in

So would you got CSM-1708-CSM-1708 or could I just do CSM then 1708 and another round of just 1708?
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Deano
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Re: Glassing in stringers

Postby Deano » Wed May 31, 2017 12:14 pm

The 'peanut butter' as you've termed it, should be viewed more as a filler for voids than as contributing any strength to any such assembly. Ultimately, the resin is not where your strength is derived, but rather from the other materials. Because of this comparative weakness, it is more prone to crack. IMO, if you have two perfectly flush surfaces one thick layer of mat may suffice, but would still be preferable to using filler material.

I would put the layer of mat between the cloth layers. It doesn't have to be real heavy/thick; even if you use something lighter/thinner it will help immensely in preventing the two layers of cloth from delaminating.
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Gary S
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Re: Glassing in stringers

Postby Gary S » Thu Jun 01, 2017 6:51 am

I always bedded my stringers in resin and micro balloons, also known as Qcells. It fills any voids between stringer and hull. layer of glass does this too,just my preference.
Definantly give your stringers a radius on the top it will make rolling it down easier. You can also use the micro balloons to make a filler and five the bottom a radius as well. Makes the bottom easier.
Another thing I personally like to do is one at a time. Although you want to level the boat front back side to side before you glass it in with only one stringer out the hull keeps it shape better and if you have to get inside it's not going to twist as bad.
I'm reluctant to say this because it is not as easy to do as it is to say. When I am using a woven material I have it precut to fit then I will wet it out on both sides on a piece of cardboard on a table. I then fold it up and place it on what I am working on and unfold it as I go. wetting it out flat is a whole lot easier than up and over a stringer.
If you have never done fiberglass work stringers aren't where I would start. Its not that hard but not a good place to learn.

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Re: Glassing in stringers

Postby joshua357 » Thu Jun 01, 2017 7:14 am

I recently picked up a 12' gilleo hull in need of glass work including stringers. I was fortunate that a client of my wife's has been glassing boats for over 40 years and came out of retirement for my project. I was going to do the work myself but for the money I am much more confident having a pro do the job.

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Re: Glassing in stringers

Postby CypressHunter » Thu Jun 01, 2017 9:41 pm

I have done some glass work just never stringers
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Re: Glassing in stringers

Postby joshua357 » Fri Jun 23, 2017 5:12 pm

CypressHunter wrote:I have done some glass work just never stringers

Stringers are done. Image


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