Stringers

edgard0

Cadet
Joined
Feb 19, 2004
Messages
10
I have a 1995 Bayliner 1800 LS Capri and I need to replace the floor and the stringer on it, can someone please let me know how to attach new stringers in??? will I have to screw them in or just attach them to the hull with fiberglass??<br /><br />Thanks!
 

ob15

Chief Petty Officer
Joined
Jan 4, 2004
Messages
514
Re: Stringers

The best way is to glue them in with epoxy. Use a thickened mixture of epxoy & either wood flour or Cabosil.
 

edgard0

Cadet
Joined
Feb 19, 2004
Messages
10
Re: Stringers

Thanks Dave...one more question, where can I get the stringers, would a regular boat repair shop have these or do I have to get them from the Bayliner directly?
 

Rhadley

Petty Officer 1st Class
Joined
Jul 20, 2003
Messages
227
Re: Stringers

You'll have to make them, I think. If you ask Bayliner, they might send you drawings for the stringers--4Winns sent them to me.<br /><br />What is the purpose of adding the wood flour to the epoxy-strength? Does it bond the stringer to the floor significantly better than plain epoxy?
 

outonbizniz2

Seaman
Joined
Feb 5, 2004
Messages
59
Re: Stringers

Hadley, the flour will form more of a peanut butter and will fill spaces where the wood stringer does not meet the hull exactly (hopefully thare are not many of these spaces).
 

JasonJ

Rear Admiral
Joined
Aug 20, 2001
Messages
4,163
Re: Stringers

Just epoxy-ing the stringer to the hull is not enough. The thickened epoxy will work great to fill irregularities, but you also have to glass the stringers in on both sides from the stringer top to the bottom and out at least 6 inches on each side. Anything less can cause torsional weakness, and the wood is not being protected. You will have to make the stringers yourself. the easiest is using ply cut to shape and married together to achieve length. Its a pain, but you'll have to create the shape. Cardboard templates work well for this. Good luck...
 

BillP

Captain
Joined
Aug 10, 2002
Messages
3,290
Re: Stringers

Make the stringers from regular stock purchased at your local lumber yard. Most folks use 2"x12"s etc cut down or plywood. <br /><br />Production boat builders (such as Pursuit in Ft. Pierce, FL) don't glue the stringers down. They sit the stringers on a thin strip of foam, then glass over it. 95% of all production boats just set the stringers in and glass over them. In other words, the stringers don't need anything but the glass to hold them to the hull. I glue them down only to keep alignment and to stop them from moving around while glassing. <br /><br />Remember that polyester resin won't stick to epoxy so if you start with epoxy the whole job has to be done with it. If you use polyester, be sure to use laminating type, not finishing type. Both work but laminating doesn't have to be sanded if glassed at different times.
 

Craig W

Petty Officer 3rd Class
Joined
Oct 29, 2003
Messages
84
Re: Stringers

Since BillP mentioned it, I'm going to elaborate a bit further on what I've come across on the to "bed" stringers to the hull or not. From ALL the freaking research I've done in the last number of months, there seemms to exist these two major trains of thought regarding how to affix stringers to the hull.<br /><br />1. Bedding the stringer down (with thickened epoxy) first will provide additional support and stiffness, and tend to keep the stringer in place while laying up the cloth/mat. Providing a VERY positive/stiff connection.<br /><br />2. The other is not to bed the stringer or use a "cushion" of foam under it (as BillP indicated), as direct contact with the hull is not required and the major support is created thru the cloth/mat lay-up. It is felt that with direct contact the higher stresses at the stringer connection will possibly lead to hull damage.<br /><br />NOW, the only problem I have relating to these two senarios is the formal application of these two techniques is somewhat gray. They both seem valid techniques, but the "do not bed" seemed (from the information I was reading) to be more related to sail boats. I tend to lean toward the "bedding the stringers down" in power boats where slight additional strength may be gained and additional rigidity would not necessarily be a bad thing.<br /><br />anyone else found anything similar thru their research?
 

crab bait

Captain
Joined
Feb 5, 2002
Messages
3,831
Re: Stringers

glue down is tried an proved.. why buck the system.. why even dare.. <br /><br />that new wave mode.. is for budding engineers, an manufactors.. <br /><br />not glue down an floatin' don't even sound right.. <br /><br />hull strenght from tite glued stringer tite from hull to floor sounds good to me.. no give unless it ALL gives together as a unit.. <br /><br />flex or give between said.. sounds not right & ugly..
 

BillP

Captain
Joined
Aug 10, 2002
Messages
3,290
Re: Stringers

Both methods have been around a long time and are proven to work. The foam method is typically used on fast ocean going wave jumpers to help spread stress loads along the stringer to hull joint.
 

edgard0

Cadet
Joined
Feb 19, 2004
Messages
10
Re: Stringers

Ok...Floor is completely out finally.....the stringers going long ways (parallel) are in good shape,Thank God....completely glassed....but now Im finding out that the floor support ones,arch like ones are rotten. The problem I have is that since they were only glassed at the ends to be attached to the hull, I now have to remove the piece stuck inside the hull that did not rot. What will be the best approach to cut the glass around those pieces to remove them without hurting the rest of the glass covering the rest of the hull.......?
 

JasonJ

Rear Admiral
Joined
Aug 20, 2001
Messages
4,163
Re: Stringers

Just cut carefully, and grind the area flat, and go from there. If you are using something with a wheel to cut with, it will be easy.
 

edgard0

Cadet
Joined
Feb 19, 2004
Messages
10
Re: Stringers

Thanks JasonJ, I will use a rotary tool I got, its like a big dremel.
 

gt1000

Cadet
Joined
Feb 27, 2004
Messages
11
Re: Stringers

Bayliner,<br /><br />A rotary tool with a cut off blade will work well. I just removed my flooring today using a handheld grinder with cut off wheel and a dremel tool with cut off wheel for the smaller areas.<br /><br />I agree with glueing down the stringers. I'm refinishing a 1977 Thundercraft trihull (16ft). The center hull has no stress crack as far a I can tell. The damage is on the outside hulls which do NOT have stringers.
 
Top