Another floor/stringer question to add to the mix

[Mark42]

Re: Another floor/stringer question to add to the mix

OOPS, DOUBLE POST.

 

[mikemerrill50]

Re: Another floor/stringer question to add to the mix

i would rather have all that fiberglass + the foam. here's a quick question for yall: how much fiberglass do you usually mix? i'm trying to figure out what size stirring sticks and mixing cups/buckets to get. also, how many tyvek suits do you think i should order? how many cartridges? i assume i need to get a full respirator mask. also, how easy is it to cut woven roving and fiberglass mat? do i need to buy special shears/scissors online? the cheapest pair are $30 on uscomposites.com. would any good pair from walmart work? thanks!

 

[mikemerrill50]

Re: Another floor/stringer question to add to the mix

n/mind... answered in another thread i started

 

[mikemerrill50]

Re: Another floor/stringer question to add to the mix

alright, i'm narrowing down to the final stage.<br /><br />here are my final questions:<br /><br />i am trying to save money, but i really want to go woodless. i want to try the hat stringer idea.<br /><br />i am thinking of getting enough 12"-wide mat tape to do two layers (and have plenty extra), and enough 18oz roving to do only one layer.<br /><br />here are my basic steps:<br />1. remove the top part of each stringer, remove the wood, leaving the fiberglass sides of the stringers intact. <br /><br />2. the sides will remain part of the structure, taking away the need to add two layers of roving. does that sound ok?<br /><br />3. using the existing roving as the base layer, i will add a layer of fiberglass mat tape along the entire stringer<br /><br />4. add a layer of roving to the entire stringer<br /><br />5. add another layer of mat tape<br /><br />6. add a final strip of mat tape along the top part.<br /><br />all in all, i will have 4 layers all around..<br /> -on the sides, i will have the original roving, plus a layer of mat, plus a new layer of roving, plus a layer of mat<br /> -on the top, a layer of mat, a new layer of roving, and two layers of mat<br /><br />of course, extra mat will be added to raise the height of the stringers to the correct level if one is lower than another, and for the final bonding with the new floor.<br /><br />does this sound ok, guys? if i don't have to do that 4th layer of roving, then i will save an extra 2 gallons of poly resin and an extra 20 yd's of 50" wide roving (a savings of about $100).<br /><br />thinking about it, if i have plenty of extra, the smartest thing would be to add fiberglass to the sides of the stringers, not to the top. does that sound right?<br /><br />thanks for all the odd questions, as i know hat stringers aren't typically done on this board. i wanna be one of the first few to do a good job at a hat stringer setup, so i can be used as an example (hopefully a good one, haha) for future jobs. i also wanna do a good job for me (no crap!). it's comin down to the time!

 

[BillP]

Re: Another floor/stringer question to add to the mix

Start with mat and THEN alternate with woven. Mat conforms to the old glass surface better and provides the best foothold.<br /><br />Yes, thicker glass on the sides is better than on top...especially if the floor sits down on the stringer.

 

[mikemerrill50]

Re: Another floor/stringer question to add to the mix

it already has some roving, so that's my plan. i will soak the roving, add mat, then roving. i'm hoping to have plenty of extra mat, so if i do, i will add it to the sides.<br /><br />thanks for the reply, bill!<br /><br />anyone else?

 

[mikemerrill50]

Re: Another floor/stringer question to add to the mix

billp, you mentioned 4 layers minimum. i may be asking a repeat question, but if it already has a layer of woven roving, and i add two layers of mat and one layer of roving, then i should be fine. right? or should i count the old layer as crap? also, since i will also be adding foam, i would be between your 4 layers of fiberglass and mark42's idea of strictly foam.<br /><br />i read more about old boats only using mat, and I am considering it. mat is soooo much cheaper than woven roving. for the cost of one layer of woven roving, i could do more than two layers of mat. so for the same price, or less, i could do 4 layers of fiberglass mat on top of the one layer of woven roving already in the boat. plus the foam will be added later (using the hole-in-the-floor method).<br /><br />i am planning on this costing lots of money, and i want to do it right, but shaving money isn't a bad thing.

 

[ondarvr]

Re: Another floor/stringer question to add to the mix

Roving is where you will get the strength you want, mat adds some, but not nearly as much a roving. The continuous strands of glass running the length of the stringer is what carries the load.

 

[mikemerrill50]

Re: Another floor/stringer question to add to the mix

alright, thanks. i'm ordering today i will use the original 1-layer of mat, 1-layer of roving, i will add 1 layer of mat, one layer of roving, one layer of mat. (total of 5 layers). wish me luck!

 

[mikemerrill50]

Re: Another floor/stringer question to add to the mix

well, i'm now officially $400 poorer. and it feels great (not really)

 

[ondarvr]

Re: Another floor/stringer question to add to the mix

The last layer of mat won't do much, so if you leave something out to save time, money or weight that's the item.

 

[mikemerrill50]

Re: Another floor/stringer question to add to the mix

i thought that too, but a book i bought said that the last layer is very important for a final seal, because water can seep through woven roving and get trapped in it. also, woven roving can start to fray over time, and the layer of mat seals it from fraying. the book actually stated you need to have two layers of mat over your woven roving to ensure those two reasons. anyone else?

 

[BillP]

Re: Another floor/stringer question to add to the mix

Regarding 4 layers and counting the old ones...IF the old glass is solid then use it. If the old is brittle and easy to break, use it only for a form.<br />Mat adds strength and stiffness to the layup. <br /><br />Fraying on stringers that are sealed under the floor is a long shot in my opinion. Abrasion or UV light doesn't happen on stringers. Just do a good glass job and give it a fill coat of resin when finished. In this application a fill coat is just plain resin applied in a heavy coat to fill the weave and seal the surface. In other applications a fill coat is used to build up a sanding surface.