Not sure what to use for the Stringers?

[gofast63]

Hi everyone,

Im currently working on a 1971 Silver line 14'. I plan on using the poly resin with the 1708 bi-axle for the transum and for the stringers. A Tech rep from US Compositis suggested that i use the Faso 110 for gluing in the stringers, but its epoxy based. Correct me if im wrong but poly donest adhere to epoxy? Any suggestions on what i can use? Or would the be okay?

Thanks,

Gary

 

[Chris1956]

Re: Not sure what to use for the Stringers?

Poly and Epoxy will adhere to each other. Of course both must be clean and sanded to help them bond. You can use poly putty or thickened poly resin to bed the stringers to the hull. No need for epoxy.

 

[gofast63]

Re: Not sure what to use for the Stringers?

Where would I get the poly puddy? Is this a cheaper method than buying the Faco 110? Also, is it good for peiceing together the transums? I'm a complete newbie when it comes to boats. Building cars are more my specialty.lol Is it recommended to have the stringers caped off? Or, can i use 12'' fiberglass tape for the sides and get away with it?

Thanks,

Gary

 

[Woodonglass]

Re: Not sure what to use for the Stringers?

Welcome to iBoats!

The first link in my signature below has a lot of good info for you. To bed your stringer and for filleting and gluing the transom to the outer skin of the boat most of the guys here on the forum use what we affectionately call "Peanut Butter" It's Poly resin mixed with Cabosil and milled fibers to the consistency of Creamy Peanut butter. I've attached a PDF file with some more helpful info as well as a link to how to make PB.

(Click the pic to download and view the PDF file)

How to Make Peanut Butter

View attachment MaterialsList.pdf

 

[gofast63]

Re: Not sure what to use for the Stringers?

Welcome to iBoats!

The first link in my signature below has a lot of good info for you. To bed your stringer and for filleting and gluing the transom to the outer skin of the boat most of the guys here on the forum use what we affectionately call "Peanut Butter" It's Poly resin mixed with Cabosil and milled fibers to the consistency of Creamy Peanut butter. I've attached a PDF file with some more helpful info as well as a link to how to make PB.

(Click the pic to download and view the PDF file)

How to Make Peanut Butter

View attachment 207874

It seems cost effective. His videos helped alot. Now Im stuck with another problem. I was able to cut the center stringer to meet with the contour of the hull. But, Im a little confused on how I can determine my deck height. In the front of the boat it measures 1 1/4''. the rear measures 1'' above the bilge area. So, Im not sure how to determine my height..... Currently i do not have any spacers underneath the stringers. Please veiw pics below..

Thanks,

Gary

 

[Woodonglass]

Re: Not sure what to use for the Stringers?

I'd use string lines taped to the sides of the hull across the beam to determine the deck height. It does not necessasarily stay constant. In most cases the deck will slope slightly from bow to stern and some times to the center form port and starboard.

 

[gofast63]

Re: Not sure what to use for the Stringers?

I'd use string lines taped to the sides of the hull across the beam to determine the deck height. It does not necessasarily stay constant. In most cases the deck will slope slightly from bow to stern and some times to the center form port and starboard.

So, i can probably cut the difference from the stern to the center so i can lay 3/4'' ply. The bow will be 1/4'' off with me using 1/4'' spacers for the springers, but i should be able to make up the difference with pb on the edges of the deck at the bow of the boat...right? Then lay csm over it. Cause i want the deck to be the same height as the bilge going towards the stern. You think thats a solid plan?


Thanks,

Gary

 

[tank1949]

Re: Not sure what to use for the Stringers?

Poly and Epoxy will adhere to each other. Of course both must be clean and sanded to help them bond. You can use poly putty or thickened poly resin to bed the stringers to the hull. No need for epoxy.

Chris,

Just a question! I am going to repair stringers this winter and I see two options: Some kind of injection system to fill void of rotten wood, or cut down in verticle and dig out rotten wood and replace with DRIED pressure treated timber, not plywood. I rebuilt 1/2 of my transom with marine ply coated and laminated with epoxie, and I have worked with poly for decades. It is my understanding that there is expoxies on the market that you can pour into voids. But, since the pressure treated timbers would be sandwitched between existing woven roving and new cloth and poly resin, I believe that this is the least expensive. Your or other's thoughts?????

 

[NickMcCabe]

Re: Not sure what to use for the Stringers?

Install stringers 1-2" higher than needed. Then shoot a lazer level from the side of the hull (where the bottom of your old deck met it). Mark on your new stringer where the lazer level is hitting every foot or so. Then use a chalk line to make a continuous line across the stringer. Rip it with your circ saw. Now that that stringer is at deck height, repeat for the next stringer, now that the one you just cut won't obstruct your lazer. If you wanted some slope from the sides to the center of the boat, you could drop each stringer a slight amount (maybe 1/8"), progressing each time to the center stringer. I would not be aggressive on that slope and possibly not even do it.

 

[chconger]

Re: Not sure what to use for the Stringers?

Chris,

Just a question! I am going to repair stringers this winter and I see two options: Some kind of injection system to fill void of rotten wood, or cut down in verticle and dig out rotten wood and replace with DRIED pressure treated timber, not plywood. I rebuilt 1/2 of my transom with marine ply coated and laminated with epoxie, and I have worked with poly for decades. It is my understanding that there is expoxies on the market that you can pour into voids. But, since the pressure treated timbers would be sandwitched between existing woven roving and new cloth and poly resin, I believe that this is the least expensive. Your or other's thoughts?????

I think you need to start a new thread there.....

 

[Woodonglass]

Re: Not sure what to use for the Stringers?

When Installing stringers, I'd recommend making them about 1-2 inches taller than needed. After they're installed and tabbed in, establish the deck line based on where the bottom of the deck will meet with the sides of the hull. Use a string with a string level or a laser level to find the line on the first stringer at various points from bow to stern and pop a string line then use jig or circular saw to cut the tops to level. Trying to make them perfect prior to install is problematic IMHO.:scared:

 

[jigngrub]

Re: Not sure what to use for the Stringers?

Use a string with a string level or a laser level to find the line on the first stringer at various points from bow to stern and pop a string line then use jig or circular saw to cut the tops to level. Trying to make them perfect prior to install is problematic IMHO.:scared:

Using any kind of level on a boat resto will require the boat to be leveled perfectly fore to aft and port to starboard before starting the demo and you should check to make sure the deck is indeed level after leveling the hull... most are not.

Hanging the level up on the shop wall and breaking out the tape measure will get the best results. Lay a straight edge on top of the gunwales and measure down to where the deck is to be placed.

The only good use for a level on a boat is for an anchor... if it's big and heavy enough!

 

[GWPSR]

Re: Not sure what to use for the Stringers?

I established string lines fore-to-aft and port-to-starboard at various places prior to demo, and recorded the vertical distances from string to hull at each point. This made plotting out the size and shape of the new material easy. I prefer to make the initial cut 1/2" to 3/4" too high, dry fit the piece and use a set of dividers set to the distance between the top of the material and string to scribe the bottom to the shape of the hull (plus an extra 1/8" for the bedding).

 

[Woodonglass]

Re: Not sure what to use for the Stringers?

JNG makes a good point. Since I usually use a cradle and do level the hull the method described works for me. However since this is not always the case, GWPSR's method of vertical measurements is a good one to. Marking the deck level on the sides of the hull and Laying a board across the sides of the hull at various locations and then measuring to the bottom of the hull will give you the stringer dimensions as well. There are many ways to acheive the same results. Whatever works best for you. It's not Brain Surgery and you'll come up with a method that works best for you I'm sure.

 

[Yacht Dr.]

Re: Not sure what to use for the Stringers?

I established string lines fore-to-aft and port-to-starboard at various places prior to demo, and recorded the vertical distances from string to hull at each point. This made plotting out the size and shape of the new material easy. I prefer to make the initial cut 1/2" to 3/4" too high, dry fit the piece and use a set of dividers set to the distance between the top of the material and string to scribe the bottom to the shape of the hull (plus an extra 1/8" for the bedding).

This is how its done if you dont have a one piece stringer/bulkhead available for a template to mark/cut from.

Good choice mate

Using any kind of level on a boat resto will require the boat to be leveled perfectly fore to aft and port to starboard before starting the demo and you should check to make sure the deck is indeed level after leveling the hull... most are not.

Hanging the level up on the shop wall and breaking out the tape measure will get the best results. Lay a straight edge on top of the gunwales and measure down to where the deck is to be placed.

The only good use for a level on a boat is for an anchor... if it's big and heavy enough!

I Totally agree with you Jignbrub. A level should be hanging on the wall unless you are putting in a power plant. It might help at that point

YD.

 

[NickMcCabe]

Re: Not sure what to use for the Stringers?

I established string lines fore-to-aft and port-to-starboard at various places prior to demo, and recorded the vertical distances from string to hull at each point. This made plotting out the size and shape of the new material easy. I prefer to make the initial cut 1/2" to 3/4" too high, dry fit the piece and use a set of dividers set to the distance between the top of the material and string to scribe the bottom to the shape of the hull (plus an extra 1/8" for the bedding).

Sounds like a great method, but I have so much tabbing on the sides of my stringers, I wouldn't be able get to the hull to measure the vertical distance from the string until after the tabbing is ground out. How did you deal with that issue or did you not have it?

 

[NSBCraig]

Re: Not sure what to use for the Stringers?

So since when did they make poly that will stick to epoxy?

 

[mwe-maxxowner]

Re: Not sure what to use for the Stringers?

So since when did they make poly that will stick to epoxy?

I'm surprised that took this long to get posted

 

[GWPSR]

Re: Not sure what to use for the Stringers?

Sounds like a great method, but I have so much tabbing on the sides of my stringers, I wouldn't be able get to the hull to measure the vertical distance from the string until after the tabbing is ground out. How did you deal with that issue or did you not have it?

My measurements were made before the stringers were removed, so they are relative to the top of the enclosed stringer and to the hull along the edge. The tabbing might be 1/8" to 1/4" thick in places, but that's why you scribe the true profile at installation. The goal is to end up at a height that matches where the sole was originally.

It's also important to measure the relative position of all members from reference points, such as the centerline, so that the new ones are in the exact same positions. Luckily, there is often a very visible 'shadow' left behind, even after grinding, that shows where they run.

 

[NickMcCabe]

Re: Not sure what to use for the Stringers?

Thanks, that is good info.