1971 Flatback

[LilRichard]

I've seen the stringer's cut in AS's and Mako's like this from the factory. I have a BIG time problem with it. It's piss poor engineering.

The hole should be cut in the dead center of the stringer. If there is not enough room for a round hole then make it oval.

Look at the chopped out section for the fuel/vent line in the right stringer.

Yeah, ya like that?  Funny- that is where a lot of the delamination (that led to their total removal) occurred.

Since I have been talking offline to Wart and Wilson about a seperate topic, I will share my thoughts here for some feedback.  Due to weight issues in this hull (motor on a porta-bracket, enclosed transom), I am thinking about removing the windows from the hull so that I can push the fuel tank all the way to the front of the V in the boat.  I hate to lose the "cool factor", but I think I would rather have my 60 gallons of fuel in front of the COG so that the boat will sit level and maybe even self bail...

[LilRichard]

Ok, nobody spoke up, and after dinner I decided to stop worrying about the windows.  They are no more:



The glass was about 1/2 an inch thick, give or take.  Here's a shot:



Here's the glass compared to a piece of 3/4" ply.  The Mako guys should like this shot...



 :)

Here it is beveled to a 12:1 ratio:



Glassing to start tomorrow.

[JimCt]

That was fast!

The viewing ports were an interesting gee-whiz feature but not really too useful.  Your progress looks great!

[LilRichard]

Thanks Jim, I hope to have it glassed up by this weekend, and *maybe* get the port stringer in too...

[RickK]

Richard - when you use the foam stringer "boards, like you have, what are your plans of securing the floor to the stringers?  Float it - no attachment?  Put a "Cap" of wood on top?  I think my liner kinda floated on the stringers, before I replaced the floor that is (if I only knew then ....)
I guess I have the same question for Shine AND I could just wait and see how both of you do this  

[LilRichard]

My plan is to secure the floor to the tops of the stringers either using a thickened resin, or possibly something like 5200.  

I'll tell you once Wart let's me know the best route  :)

[warthog5]

5200 and some temp drywall screws. After a day or two remove the screw's, fill the hole's with some runny resign/Cabisol and then lay the glass over the top of the floor.

[LilRichard]

There's your answer Rick!

Wart has given me some great advice, and hopefully will be kind enough to continue.

[Tim/GA]

Not Warthog but...

I use resin thickened with cabosil AND 1/4 chopped fiberglass.  Cabosil is strong but can be a bit brittle, the chopped glass makes it better.  Think concrete with figerglass added for a comparison.  I used this mix any time I am "glueing".

[warthog5]

That will work too.

But it takes more time to make and you need to hussle to get it all down and the deck laid in place.

It's much easier to shoot something out of a calking gun.

It's not uncommon when removing a motor bracket that the 5200 will pull the gellcoat right off the fiberglass. That's pretty strong.

[LilRichard]

Didn't want to scare anyone off from responding to my posts, nor offering advice- I was just laughin that soneone was asking my advice when I get most of it from Wart anyway...

But that being said, while some of you folks were out enjoying the AS meeting, I was grinding fibergalss...  

You saw the pics of the missing windows, well here are soime pics of how I covered up the holes.





I laid up six layers of glass to cover those holes - I did not want a failure.  There are 3 layers of 1808 and 3 layers of 2415, at increasing width.

Next I moved onto my stingers.  I set them up with resin thickened with Cabosil, and then I tabbed them in.





After that, I laid in progressively larger layers of 1808, 3 in all.





I was using 38" wide fabric, so you might notice the seams.  I made sure to overlap and stagger the seams.

Next weekend I plan to get the starboard stringer in - time to order my tank!

[warthog5]

That's looking good Rich.   What did you end up using as a backing plate/mold on the bottom of the boat for the spy hole's?


I was afraid you would have void's on those top square corner's on the stringer, but it look's like you handled that just fine.

On the stringer's I would just butt the same layer, but have the butt's staggered between layer's.

The extension to the stringer going aft you can stagger those joint's in the glass too. leave what you have there and sand it. When the next section of stringer goes in the glass will go from one section to the next and butt to that layer that is stopped short of the end.

make your stagger's at least 6in, but 12in would be better.

[LilRichard]

Thanks Wart.  I think the reason the tops of the stringers were easier is because I shaved a 45* angle on the corners... hoping to ease the bend a little.  Seems to have worked - I will do the same for the next stringer!

Oh, and I used luan with visqueen as my backer... just like someone recommended.  

[LilRichard]

Well I got the starboard stringer in today...  Same process as the port side- 3lb foam tabbed in, then glassed over with 3 layers of 1808.  







I have my tank on order from RDS, should get it around Dec 1.  Then I will begin building the bulkheads.

[John Jones]

Looking good Rich.


Wart,
You ever thought about writing a book?  I'm serious.  All the books available are out of date and seem to concentrate on snailboats.