What material for stringer install?

[Racer67]

I'm installing new stringers on an extremely tight budget. I'm using 1708. But what thickness (how many oz) should it be? Also any particular epoxy to use?

Thanks!

 

[sheboyganjohn]

Don't need the mat on the 1708 with epoxy. If you already have the 1708 go with poly. I order my poly off of E-bay $145 delivered. For epoxy I use aeromarine and they are $340 plus shipping for 6 gallons. If you do not have the 1708 then you can go with epoxy and biax without the mat.

 

[jigngrub]

1708 is the weight of the cloth, it's a 17 oz. per square yd. cloth with an 8 oz. per yard CSM backing for a combined weight of 25 oz. per sq. yd.

I agree with SJ, polyester resin is about half the price of epoxy and is what you want to use if you're on a budget.

 

[sheboyganjohn]

Minor correction, the 8 is 0.8 oz of CSM. From UScomposites website
~~Contains double bias(17oz) stitched at 45degrees
along with one layer of 3/4oz mat.
Thickness: 0.044"

 

[jigngrub]

A more precise correction would be .88 oz.

There's 8 oz. per square yd., there's 9 square feet per square yard, 8 divided by 9 = .88 oz. per square foot... that's where the .8 oz.(most round it to 3/4) 1.5 oz., and 2 oz. come from... weight per square foot.

1.5 oz. CSM is 13.5 oz. per sq. yd and 2 oz. is 18 oz. per sq. yd.

 

[Racer67]

Thanks for the reply guys. Went down to the boat shop today and got the stuff. I saw this thing called Six10, it's a thickened epoxy premixed. Info is here:
http://www.westmarine.com/adhesives/west-system--six10-thickened-epoxy-adhesive--10287571

Would this be the stuff that goes under the stringer to 'cushion' it and keep the hull from being to solid and possible cracking. Seen the term Peanut Butter and this appears to be the stuff. How thick should it be under the stringer? 1/4"?

 

[jbcurt00]

Have you committed to using epoxy for ALL the repairs? Or as J&G suggested, are you using polyester resin & the newly acquired 1708?

 

[Racer67]

I am using the polyester resin. 3 layers. I spoke with the guy at the boat shop and he set me up with everything. Doing the first layer of 1.5oz fiberglass, a 1708 layer, then another 1.5oz layer.

 

[jbcurt00]

If you are using poly, then you DON'T want epoxy under the stringers. Make your own poly based filler (PB).
The 1/4" bedding under the stringers is to keep the relatively thin stringer from acting like a point load when stress flexes the fiberglass hull. The bedding makes a much larger foot for the stringers. Like a snowshoe when walking, spreads the load of your body's weight across a much larger area then just a typical boot.