three questions

[jesters420]

first question, do i need to completely grind off everything that is existing from the rotten stringers down to the bare hull or clean up enough of the glass and body filler so i can replace it? it is body filler isn't it? second, do i have to replace the stringers with one piece or can i butt two together because the new glass will be the support. thanks for the help. just got a web page so the pictures will be coming soon.

 

[studlymandingo]

Re: three questions

What will you be using to construct your new stringers?

 

[brownies]

Re: three questions

If stringers are rotten, remove them and grind down to smooth hull....and start again fresh.<br /> You "can" butt them together, but, I've never thought of that as an acceptable job.<br /> You are "alread there", might as well do the whole stringer and not have to worry about it. Then again..."while your at it" can be cause for much more money and work.

 

[jesters420]

Re: three questions

most of the posts i have seen say to use 5 ply outdoor, so that is what i am planning to use. we had some sheets of 3/4 in. at work that were going to be thrown out but they are 8 ft. i need 9 ft. looks like i should just go ahead and get two 10x5 ft. need the other for the floor. i would like to do it right the first time. thanks brownies. i am cheap, but i want to feel comfortable when i am done. do i use bondo between the stringer and the hull?

 

[Realgun]

Re: three questions

If you need to "butt" the wood to make it longer there is a way.<br /><br />DO not butt two piece togeter you need to scarf them. 1:7 In other words if you two pieces are 2 inces in 1 direction ie: a 2x4. Then you need to cut fromthe top edge to 14 inces on the bottom.<br />on both pieces <br />

<br /><br />Remove the pink area and join the wood with epoxy. The scarf spreads the forces out. The wood will break before the epoxy joint but if there is not enough "give" the boat will break rather than flex in rough seas.

 

[studlymandingo]

Re: three questions

Good illustration Realgun. That will be a great reference for people attempting stringer replacement for the first time. I did my first stringer job before Al Gore invented the internet. A lot of feeling my way through. I got the job done, but it would have been so much easier and smoother if I had such an invaluable resource.

 

[jesters420]

Re: three questions

thanks realgun but i think that i will just go ahead and buy two 10x5 sheets. one for the stringers and the other for the floor. i still need to know if it is bondo that i use between the hull and the stringers and the hull and the floor. thanks for any help. if it was the choice of anybody that replies which would you do? use four 4x8 3/4 in. outdoor sheets for free and scarf them together or just spend the money and have them all one solid piece? thanks again!

 

[Realgun]

Re: three questions

I have seen here to mix an epoxy putty and use that to hold the stringer to the floor. That way you do not get any gaps that can cause stress points on the hull.<br /><br />Scarf is going to be the same as 1 piece its not the glue thats weak its the wood. The stringer if it was going to break/crack will probably not break or crack on the scarf joint.

 

[studlymandingo]

Re: three questions

No bondo, it is porous. Take realgun's advice...Epoxy. The scarf joint is perfectly fine, you can even stagger the joints when laminating several sheets together; that will never come apart.

 

[brownies]

Re: three questions

Bondo will work fine to hold the stringers in place. But, that's all it will do.<br />It is porus, but, so is most of a boat (your stringers and floor) when you get right down to it.<br /> You will be encasing the stringers and the bondo that you "set" them in, in fiberglass. This may not seal them off completely, but, it's suppossed to and it's "how it's done".<br /> (if it sealed em off completely, then you wouldn't be replacing them.......)<br /> You can probably do a better job than the manufacturer though. Spend more time, attention and glass there than they did.<br /><br /> If joining/splicing, use the advice Realgun shows above. That method will work fine for joints.

 

[Tail_Gunner]

Re: three questions

After a lot of research i found a very cost effective and super strong solution. 3m has a Windo Weld urethane (08609) that cost only $8.00 a tube, it took four tubes but now the stringers are sitting on a 3/8 urethane cushion. And as far as stength and deformation it will take any schock a boat can withstand.....probably more than the boat. However using West systems resign in a penut butter form makes me think all that work was for not, i mean now the stringers do have a bed on which they seat but the epoxy is bonded to both the floor and the stringer (sides) that sure seems like a hard spot to me?

 

[jesters420]

Re: three questions

thanks for all the help guys, but it seems one person says bondo and another says epoxy and another says window weld. which of these should work the best to set the stringers and floor in place before i fiberglass? can i also scarf the floor in or should that be one piece? i don't have a problem paying for the material if i should, but if it is just as strong to scarf then there seems no need to buy full 10x5 sheets if i can get the ones from work for free.

 

[tashasdaddy]

Re: three questions

jesters, it get down the labor and the work, as far a the scarfing goes. it take time to make the joints. if you have plenty of time i'd got the scarf way, if not and you have plenty of money and little time, i'd got the 10x5 way. the floor can go in in several sheets, just glass the joints. ther has always been a debate about bondo, i say buy one item and keep to it, why have a bunch of left over product.

 

[BillP]

Re: three questions

It doesn't really matter what is used under the stringers. Different boat factories use different methods and they all work. Most set the stringers directly on the hull and just tack them down with resin to hold for glassing. High end boats like Pursuit use foam under their plywood stringers to spread the load out. The glass that holds stringers down is what matters.

 

[jesters420]

Re: three questions

thanks for all the help. i am just glad i found this, there is a lot of information here and a great bunch of people willing to help out.going to finish grinding off the debris in the hull today. can anyone help me with a shopping list? how much mat, roven woven, resin, hardener and anything else i might need for the stringers and floor for a 19'6 sea ray. floor is aprox. 9'5 and have two stingers. thanks again!

 

[BillP]

Re: three questions

Measure the square footage (or sq yd)being glassed. Decide what type glass and how many layers. Then calculate how many oz per sq ft (or sq yd) of glass it is. Calculate one oz of resin for every oz of glass per sq ft (or sq yd). Note that rovin woving is sold in oz per yd and mat is sold as oz per sq ft. Add for waste, coating, etc. That's how you estimate glasswork.