NEW BOATER!! Repairing stringers

[rickryder]

You want cabosil and 1/4" Chopped Strand to add as filler....you can get it here.....uscomposites.com
When you want to do your fillets here is a few tips. Mix up your quart of PB and load it into a gallon zip loc bag...cut the corner of the bag and pipe it like mortar or icing .. once you set your stringer use a large metal spoon dipped in acetone to do your fillet cove at the bottom of the stringer....It should look like the pics on post # 76 in my thread below.

 

[Bigreddon]

To Heck with what the Factory did, 1/4" is all you need. You can do it BETTER than they did!!! Also, add more filler to the mix so the PB is thick and gooey like Peanut Butter and it will stay in place and not run out from under the stringer. Add some Chopped up fibers to the mix as well. You should have to use a putty knife to spread it into place.

I had a good consistency of peanut butter ...until I thought it would "dam up" the thin epoxy. The thin stuff diluted my peanut butter after I had it applied...

 

[Woodonglass]

You lost me..."Dam Up" the thin epoxy????

Since you're using epoxy you can use just about anything for filler material. You can use fine sawdust, Flour, Baby Powder etc. Polyester resin will work just fine on your Polyester resin built boat. You don't have to use the expensive epoxy and mixing the hardener is easy if you use the metric system. 1000 ml of resin uses 15 ml of hardener. Disposable graduated measuring cups makes it easy to measure and pour.

 

[rickryder]

Hmmm guess you can't put a link to us composites . com for fiberglass supplies. ..

 

[alldodge]

You guys are the experts but the original stringers used for the most part air as the gap. My Formula has nothing but air between the hull and stringers.

 

[Woodonglass]

AD, Your hull is over 20 ft. Different Building techniques are utilized once a hull exceeds 20 ft in length. I suspect the walls of your stringers are a bit more substantial as well.

 

[Bigreddon]

You guys are the experts but the original stringers used for the most part air as the gap. My Formula has nothing but air between the hull and stringers.

So this is the first I've heard about leaving an air gap. Here's the thing: at the transom end of the stringer, the stringer was on the hull(or epoxied to it..) moving toward the bow, there eventually was a gap that was not completely void, but had what looked like chopped fiberglass with no resin. (See previous pics) the stringer at these areas was a good 3/4 inch above the hull. Am I wasting time and money filling all this in? The stringers had a fairly substantial amount of glass around them...

 

[Woodonglass]

Technically speaking a stringer can be hollow but...in your case you shouldn't be thinking this way. Unless you want to use a LOT more Resin and Glass to beef up the laminations to carry the load. Stay with the accepted methods of installing stringers in a boat of your size. Bed them in PB and use two layers of 1708 to tab them to the hull and move on. DON'T get Paralysis by Analysis and overthink this. I've seen this happen a lot here on the forum and it always ends up the same...Stringers bedded in either PL or PB. NEVER seen anyone yet do them lifted off the hull or hollow!!!!

 

[Bigreddon]

Thanks for the tips on filler and filleting. After sanding out a lot of resin, I recovered that dust and used it as filler. I now have one stringer done!!! The second one will be easy enough now that I have a procedure. I w sanded either side of the stringer to accept the resin for the glass. I'll cut out my last bit of glass for the second stringer this evening. Thanks everyone!!!!!

 

[rickryder]

Post some pics of your work

 

[Bigreddon]

I'm going to do some work this weekend and will post some photos of the stringers In Their new beds. As I said, one stringer is done, and I have removed the glass for the other now, as well as the old glasswhere the sole met the hull.

Have a merry Xmas y'all!!!!

 

[Bigreddon]

You lost me..."Dam Up" the thin epoxy????


Since you're using epoxy you can use just about anything for filler material. You can use fine sawdust, Flour, Baby Powder etc. Polyester resin will work just fine on your Polyester resin built boat. You don't have to use the expensive epoxy and mixing the hardener is easy if you use the metric system. 1000 ml of resin uses 15 ml of hardener. Disposable graduated measuring cups makes it easy to measure and pour.

Can I use those fillers in polyester resin to make PB? You said "since I'm using epoxy resin I can use those filers"

I got $150 west marine gift card for Xmas, and now need roving and resin to finish the sole. If I can get by with poly resin and flour...that will save me some $$!!

 

[jbcurt00]

No i wouldnt use flour w poly resin, or sawdust

Epoxy and poly are different. Cabosil and micro balloons arent particularly expensive use those. Save your glass scraps and cut them up for use as fillers too.

 

[Woodonglass]

JBC is absolutely correct epoxy allows you to use just about anything as filler but poly requires you to use products that are compatible. He has given you great advice

 

[rickryder]

Instead of roving use 1708 biax cloth... much better IMO. Epoxy is great stuff but expensive...remember once you use epoxy you can not go over it with poly...it won't adhere to the epoxy. 5 gallons of poly is $125 + shipping .....epoxy will run around $300...more than double the price..

 

[alldodge]

Wonder if VE resin would be a better choice :noidea:

 

[Bigreddon]

I've found 1708 fiberglass, and it "comes with one layer of mat". What do I use the mat for? I'm planning on doing two layers of 1708 over each stringer, tabbed onto the hull. My question is...may i use the one lawyer of mat before the 1708? (Resulting in two layers over the stringer)

 

[Arawak]

1708 is 17oz biaxial with 0.8 oz CSM (mat) either stitched or bound to it. If you're using polyester resin, you need the CSM to make the bond between layers. If you're using epoxy, you don't need the CSM, you'd want just 17oz (or 12oz) biaxial. I'm not clear on which resin you are using.

 

[Bigreddon]

I am using epoxy resin. Can I then save the csm for later use ...like on my plywood for the sole? Thanks for the info !!

Oh wait ...you say the csm is bound together. So...can I just use one layer of 1708 with its csm for the stringers? Or do I need to double up the layers?

 

[Bigreddon]

Technically speaking a stringer can be hollow but...in your case you shouldn't be thinking this way. Unless you want to use a LOT more Resin and Glass to beef up the laminations to carry the load. Stay with the accepted methods of installing stringers in a boat of your size. Bed them in PB and use two layers of 1708 to tab them to the hull and move on. DON'T get Paralysis by Analysis and overthink this. I've seen this happen a lot here on the forum and it always ends up the same...Stringers bedded in either PL or PB. NEVER seen anyone yet do them lifted off the hull or hollow!!!!

This the advice of two layers of which I speak....I guess in reading this now, I understand it is two layers of 1708 (17 being the glass...08 being the csm). Right?