transom and Stringers

Woodonglass

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Dec 29, 2009
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It'll be a Piece of Cake!!! If you've done a dry run then you already know how it's gunna be. The Nice thing about epoxy is it gives you some extra time. No Worries!!!
 

rickryder

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If you need to fill gaps with PB use a gallon zip loc bag fill with some pb snip the corner off and use it like an icing piping bag...also use a metal spoon dipped in acetone to make your fillets....makes a nice transition point... You have planned your work now you can work your plan! You'll do a fine job I'm sure ;)
 

jigngrub

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With that many relief holes you may be at risk of squeezing out too much glue and weakening your bond. That's one of the reasons I don't use relief holes nor do I have to worry about squeezing my work too tight. Other reasons are having to clean up the mess that's going to make and having to go back and patch all of those holes. You'll see what I'm talking about tomorrow.
 

rickryder

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With that many relief holes you may be at risk of squeezing out too much glue and weakening your bond. That's one of the reasons I don't use relief holes nor do I have to worry about squeezing my work too tight. Other reasons are having to clean up the mess that's going to make and having to go back and patch all of those holes. You'll see what I'm talking about tomorrow.



If you look back at post #169 you will see only 12 of those are thru holes.....the others are the indents from the screws
 

Woodonglass

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Yeah, it's REAL messy as you can see from Nursemans install:D As long as your PB is the right consistency it will be fine. Just scrape it off and use it for the fillets. You'll have the same amount of resin on the back of the transom as you would have if you didn't drill any holes at all!!! The "Rivets" give you a Stronger bond to the hull NOT a weaker one because you actually have more surface area glued to the hull if you THINK about it.

20140830_110000_zpsfc69e46e.jpg
 

CT River Runner

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Yup, only 12 1/2" holes. The screw holes filed with resin. I will be using using excess glue for my filets. I want able to glue it today because of snow storm. I wad able to have everything ready for tomorrow morning. All laid out and washed. Ready to go!
 

jigngrub

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Yup, only 12 1/2" holes. The screw holes filed with resin. I will be using using excess glue for my filets. I want able to glue it today because of snow storm. I wad able to have everything ready for tomorrow morning. All laid out and washed. Ready to go!

Sounds like a plan!

You don't have to wash unless you get an amine blush, and I thought you were using non-blushing epoxy? You'll know if the epoxy blushes, it'll leave a sticky residue like someone spilled pancake syrup all over your finish. There's no mistaking it. The blush will come from low working temps, higher humidity, and lack of air movement... or at least that's when it always happens to me.

I do like to sand my epoxy with 100-120 grit to dull the finish and remove all the "shine", gives the adhesive a good grip.

You should be good with only 12 relief holes, but they generally aren't needed with an aggressive clamping system like the strong-back method. Relief holes are needed for the weaker "chop stick" type clamps though, you just can't get enough pressure with them to force the adhesive from the middle of the transom out to the edges... so you have to drill holes to give the adhesive a shortcut out of the transom. And you don't need relief hole "rivets" to hold the transom core to the fiberglass skin. Ask anyone that has removed a half rotted transom that still has good wood bonded to the transom, it's a fight to get the good wood out.
 

jc55

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Nov 3, 2006
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I know that "chopstick clamps" are popular here, but you're going to get a heck of a lot more even clamping power if you put the C-clamp on the 2x4 just below the top of the transom. As with anything popular, many people are going to buck it, but run the experiment yourself with two pencils. It's a matter of leverage.

Also another issue with this style of clamping is that you can leave vertical "waves" in the outer transom skin that will need to be faired and sanded if you're going for perfection. I use custom "pusher" clamps by modifying bar clamps to help push on the inside of the transom. That might be ideal for an I/O transom...

73d36dec-b230-4edc-90ed-6fef5d786393_400.jpg


I customize them so that the end flips around and you push instead of clamp.
 

jigngrub

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Also another issue with this style of clamping is that you can leave vertical "waves" in the outer transom skin that will need to be faired and sanded if you're going for perfection.

The best way to alleviate this problem is to use a "backer board" on the outside of the transom. A piece of 3/4" plywood the full width and height of the transom held up against the outside of the transom before clamping members are installed. This will help to more evenly distribute the compression forces of the clamping process. This will give you a smooth and uniform outer transom skin and a uniform layer of adhesive between the transom core and inner skin. I'll be using this method on my build.
 

JASinIL2006

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Feb 10, 2012
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The best way to alleviate this problem is to use a "backer board" on the outside of the transom. A piece of 3/4" plywood the full width and height of the transom held up against the outside of the transom before clamping members are installed. This will help to more evenly distribute the compression forces of the clamping process. This will give you a smooth and uniform outer transom skin and a uniform layer of adhesive between the transom core and inner skin. I'll be using this method on my build.

I did this (although my backer board was primarily to keep the keyhole area flat and uniform) and it really worked well.
 

CT River Runner

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Jan 5, 2015
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All clamped! I didn't use a backer board. Hopefully it will turn out alright. Didn't go real bad. Most of my relief holes had putty come out, some were half way. I'll fill em. Pretty messy around key hole. That's a about it. Other than that I feel really comfortable with this brand new transom! I'm going to leave the clamps on for about a week. I have a little bit of room to do my filets. I'll have to wait for clamps on some area's.
 

rickryder

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Jun 24, 2010
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Hope you coated those bolts with some type of grease .....would hate to see them epoxied into the transom :eek:
 

jc55

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The best way to alleviate this problem is to use a "backer board" on the outside of the transom. A piece of 3/4" plywood the full width and height of the transom held up against the outside of the transom before clamping members are installed. This will help to more evenly distribute the compression forces of the clamping process. This will give you a smooth and uniform outer transom skin and a uniform layer of adhesive between the transom core and inner skin. I'll be using this method on my build.

Yup, I did that on my second transom, lesson learned.

Great job CT! You did it!
 

jigngrub

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Mar 19, 2011
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Hope you coated those bolts with some type of grease .....would hate to see them epoxied into the transom :eek:

Nah, double nut one end and they'll unscrew. Will leave nice threads to hold the patch.

Transom looks good CT and is better than the factory job that came with the boat new.
 
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