Can I skip the stringer epoxy soaking? Can I use resin instead?

[alheim]

I feel like I've read every post on the forum - at least 5 times. Of course, that's an overstatement. But regardless, I'm antsy to begin glassing.<br /><br />Cliffnotes: Replacing stringers and floor. I've decided to use polyester resin to save money, and besdies, I feel like polyester is what the boat was made with anyway - and that if it's done right, it'll last.<br /><br />So, my questions:<br />1) Everyone seems to say to soak or coat the stringers/all wood in Epoxy before I bed them in (with peanut butter) and then glass them. But I'd rather not pay for Epoxy. Could I instead use my resin to coat the wood? Could I skip the soaking step altogether (I think this was my original plan) and just glass everything well?<br /><br />2) I've read to use mat (chopped strand) as the first layer on all stringers, then cloth next. However, I found a great eBay deal on 10cloth, and don't feel like buying mat if it's unnecessary. What do you guys think about that? Should I definitely use mat for the first layer? I mean, I guess I am being cheap, and could afford some mat if needed.<br /><br />Is 10oz cloth overkill - will I be able to work with it?<br /><br />I guess this is a shadow of OCD kicking in - but these may be crucial questions. This is my first glassing project, and I'm very stoked, but also anxious. These forums rock, and I've learned tons. I have more questions, but they'll wait.<br /><br />-Alheim

 

[lingcod]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

do not skip the part about encapsulating the stringers. you need to coat the wood a couple of times before you start glassing or the resin from your glass will just soak into the wood and you'll end up with a dry glass job. yes you can use poly to do the encapsulating and you should if poly is what you are using for the rest of the project.<br /><br />as far as the mat goes, it is alot stronger than the cloth. the plan should be.... mat,cloth,mat cloth. this will give you the strength and the buildup necesary for a strong,coplete structure.you could do the resto as you planned, no soaking and no mat, just plan on doing the whole thing again very soon. someone here has a sig line that says "why is it there is never time do do it right but always time to do it twice?" nuff said

 

[ondarvr]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

Welcome Alheim<br /><br /><br />1. Don't mix and match epoxy and polyester (poly won't bond to epoxy), just use one or the other, so precoat the wood with poly.<br /><br />2. You need to use mat as a first layer any time you use poly, so ya gotta buy it.<br /><br />10 oz cloth is underkill, 18 or 24 oz roving over mat is what's normally used, many times multiple layers of each.<br />What was it you took out, was it mat and roving, and how many layers of each?<br />It's OK to use the cloth, but you may need to use more layers to match what came out.<br /><br />I don't think you'll have any problems working with cloth, it's pretty easy. When you first start mixing resin, don't mix a large amount, start small until you get the feel of it. <br /><br />Good luck

 

[ondarvr]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

LCJ<br /><br />Ya beat me to it.

 

[KRS]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

Most mats (that I've seen) require have a bonding agent that can only be dissolved by poly resin. So whatever you decide, be sure your mat is compatible.

 

[alheim]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

Originally posted by ondarvr:<br />10 oz cloth is underkill, 18 or 24 oz roving over mat is what's normally used, many times multiple layers of each.<br />What was it you took out, was it mat and roving, and how many layers of each?<br />It's OK to use the cloth, but you may need to use more layers to match what came out.

Wow, thanks for the really, really quick replies, guys.<br /><br />10oz is underkill for glassing the stringers, hrmm? Well, okay, sounds good to me. And, I was under the impression that the cloth was far superior to chopped strand for some reason. Not sure why I thought that. I also thought that becuase you were using TEN oz. cloth as opposed to ONE and a half oz. mat, that you'd have to use less. I think that is indeed wrong.<br /><br />I think what I took out was only chopped strand mat.<br /><br />Instead of alternating mat/cloth/mat/cloth, could one use only mat? So, mat/mat/mat. Again, I wouldn't know how many laters.<br /><br />My understanding is solidifying..

 

[ondarvr]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

Mat isn't actually stronger than cloth, but you need the combination of the two for the best results. Just using mat can work, but if you use cloth (or roving) also, it will be much stronger. The weights are measured differently for chop strand mat and woven products, mat is by the square foot, woven products are by the yard.

 

[OldBoatGuy12]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

Mat IS actually stronger than cloth. Mat is not directional, meaning that the fibers go everywhere in any direction. You get your strength from that because your strength is in all directions. Cloth has fibers running in 2 directions. You can be strong in one direction, but others will suffer. At least that's the way I understand it.

 

[SS MAYFLOAT]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

If the mat is structuraly stronger, then why is the majority of boats have the hull first laid in with the cloth? My understanding is that the woven cloth, the fibers are locked in unlike the mat.<br /><br />Once it is all resin'd in, it is to be a solid piece. If the fibers give and move, then the resin has failed. If that happens, it is an idication not enough layers were put in. <br /><br />One of the most important things is to make sure that the resin is forced up through the mat/cloth when it is being laid. I've seen too many DIY jobs where resin is put in, then the cloth/mat and then resin poured or brushed on top of it. This makes for a weak job. In order to have a strong repair, you must compress the layers and force the resin through the cloth/mat to the surface. Voids of resin are weak spots. Resin alone is not strong, it is the cloth/mat held with the resin is what creates the strength.<br /><br />There are special rollers that have grooves in them to help press down the cloth/mat and makes the resin soak through. I made mine out of different size flat washers.<br /><br />This is just what I understand and not looking for any arguements. Maybe I'm wrong, but to others I maybe right. I know what I do works for me.<br /><br />As for alheim, if it was mine, a couple of layers of cloth, then 3 or 4 layers of mat. That is how I do mine. Works for the manufactures, so I copy what they do. Good Luck

 

[ondarvr]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

A layup using only mat is one of the weakest methods of construction. While still strong and stiff, it is far less able to handle the loads when compared to woven or nitted fabrics. The shorter random strands in mat (or chop) add bulk and stiffness (not to be confused with strength), but it's the long continuous strands that do the work. Mat is needed in a normal hand layup though, it will improve the bond when using poly and will hold resin so it doesn't drain out of the roving. Newer methods of construction use less and less mat and roving and more nitted products (continuous strands that are not woven, they lay flat and are stitched together, some in combination with a 3/4 oz mat), these laminates can be made much thinner and still be stronger, but that makes them more flexible, so at times mat or some type of core is added to increase stiffness.<br /><br />At times Cloth is used as a generic term for all fiberglass fabrics (but not in the industry), it's a more finely (smaller fiber bundles) woven product very much like roving. Cloth is about the least used type of glass in making production boats, the cost is high and the strength per layer is low when compared to other woven or nitted goods.

 

[alheim]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

Heh, this thread isn't bad for my first post. Thanks again for all of the replies.<br /><br />I know what I'm going to do now.<br /><br />Last questions (maybe) (not really):<br /><br />After coating the floor with resin, I'll secure it with peanut butter, along with just a coat of cloth on top. Good?<br /><br />Predrilled holes for SS screws to hold flooring: Is filling them with resin sufficient? Or do you recommend a drop of 3m 5200 or something else .. which I can get a tube of pretty cheaply on eBay.<br /><br />-Alheim

 

[ondarvr]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

The cloth will be OK, but it will bond better with a 3/4 oz mat under it. Use 5200 in the holes, resin by itself is brittle, so any stress on the screws can crack the resin and let water in. If these screws will be covered when you glass in the floor, it won't make any difference.

 

[ondarvr]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

Where the floor meets the hull, you WILL need to use mat under the cloth and you will need to build this area up thicker. 3 mat and 3 cloth should work.

 

[OldBoatGuy12]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

Alright, so I'm confused a bit now. I understand that separate layers is the way to optimum strength, but I've always heard(and practiced)that cloth is used as buildup in between layers of mat. I know that woven fabrics(such as carbon fiber or kevlar) are much stronger,as in tensile strengh, but I just don't see cloth being strong enough to do much good. Now, If you are making a distinction between woven roving and cloths, which are definately NOT as strong, it makes sense.

 

[studlymandingo]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

Just a side note: I was reading up on the 3M products and found that the 5200 AND the 4200 are not rated to bond with many metals and plastics; they are rated for wood and fiberglass. The 4000 however is rated to bond with plastics and metals, seems like this may be a better product for imbedding the screws.

 

[Realgun]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

Alheim, if you use peanut butter use the 1/4th inch or longer fibers. make it real stiff and push it into the cracks with a putty knife. I dont know if you need more roveing or not. I used epoxy and there is only 2 layers of cloth over that. I did not have the carpet layed and got into some nice waves. If there was going to be a structural problem it would have happened then. As far as I can see the floor and hull joint are doing well.<br /><br />Having said that, I used epoxy which is a bit more flexable than polyester. Do what the poly guys say and you should be fine.

 

[Realgun]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

And if you don't think peanut butter is strong then you should see my seats.<br /><br />I mounted the seats to a piece of plywood 10 inces wide but 11-13 inches the other direction. The seat is on a 9 inch round plate. I put T-nuts on the bottom of the plywood and the seats bolt to these. Then the plywood base is glued to the tops of the floot with peanut butter. I weigh quite a bit and the seats are still holding up fine.

 

[OldBoatGuy12]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

What's this peanut butter yall speak of?

 

[bigbad 4cyl x2]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

wow did you see that guy selling the full roll of west systems eglass cloth on ebay ; http://cgi.ebay.com/ebaymotors/ws/e...=4647020147&rd=1&sspagename=STRK:MESE:IT&rd=1 ;that would work good for your project.

 

[ondarvr]

Re: Can I skip the stringer epoxy soaking? Can I use resin instead?

co<br /><br />I am only talking about glass fibers, not comparing them to other types. <br /><br />Peanut butter is putty, you can add many different things to resin that will thicken it to make putty. Milled fiber (glass fibers) is used for strength, but makes a more difficult putty to use, so combinations of things are used to get strength, light weight and good working characteristics.