1971 Flatback

[John Jones]

I gave up on yahoo and msn search and only use google now.

[RickK]

I ordered a sample pack of the 2oz cheapo ($15) suits - should keep the fiberglass dust out (I hope).
Thanks for the lead.

[LilRichard]

The pseudo-wife was out of town this weekend, so I had plenty of time to get 'er done.

Continuations of bulkheads out to hull sides complete:









I also started work on the transom knees:





My goal of having the floor in by April still stands... hoping I can make it.  I bought some 3" PVC today to start building rigging tubes... still have one more set of bulkhead "wings" (extentions to sides of hull) to complete.  From there, I think I can start cutting floor panels.

[JimCt]

Really rolling along!  I'd pay cold hard cash for a weeks worth of Fl weather about now.

You've got to cut into some of that nice new grid work to put the tubes in?  If so, I hope you don't cut notches in the grid... better to drill holes with a rt. angle drill & hole saw.  Notches will weaken the structure; holes won't.

[LilRichard]

Right on Jim, holes, not notches.  

Oh, except for the fuel fill lines.  

 

My fuel tank leaves me no room to run through the stringer, thus I have to notch it... even to Wart's dismay.  I plan on double reinforcing that area (it'll be about 2" deep by 3" wide).  If anyone has a better idea, let me know.

[JimCt]

Cut a semi-circle if you can.   Square corner is a break waiting to happen.

[LilRichard]

I had been wondering about that... I think you may be right.  Like I said- either way I will reinforce the area with some extra glass... trying to avoid that problem.

[warthog5]

Also try to use PVC elect sweep's, instead of 90 degree turn's on your rigging tubes.

[LilRichard]

Wart- that's a good idea.  I looked at electrical conduit sweeps and a 3" sweep is HUGE.  I actually picked up a PVC plumbing (sewer) sweep- wider that a standard 90deg bend, not as wide as an electric conduit.

[warthog5]

That will work, but the elect sweeps are easier to maneuver wires thru.

[LilRichard]

I agree Wart- but it is important to note that my hull is flat at the rear, and my stringers are only about 10" in height.  The 3" elect sweeps require close to 16".

[LilRichard]

So between marriage and honeymoon... well Ok, afterward... I got some work done.  On a positive note, I got the rest of the stringer work complete.  Here is a shot from the transom- blocked partially by the fan and tools in the boat:



As you can see, I have cut the holes to run the rigging tubes through, as well as the in and outflows for the livewell.

Also, I got the transom knees done:



Last- the notch in the Stbd stringer for the fuel and vent lines (still need to glass over):



Now the bad news.  I am ready to mount the spray rails (prior to dropping the floor in), and decided to patch a "few" of the spider cracks in the gelcoat.  I started grinding away the cracks... and grinding, and grinding...



As it turns out, it looks like I had quite a bit of hullside flexing around the floor.  I have ground it all out, and will start building back with 1808 then mat.  from there I will fair it out, then bolt (and glue) on my spray rails.

Here's a shot form the Stbd- yuck:



I guess the bright side is I will not have to worry about any more gelcoat cracking and crazing.  

Now my question is: before I mount the spray rails, my plan is to seal up the bare glass with a barrier coat... will that be sufficient to protect the fiberglass should water get between the rail and the hull?

[LilRichard]

Sorry I have not checked in for a while... been busy as usual, and then I managed to get the stomach bug...  :cry:

Anyway, my project continually tosses me curve balls- and here is the latest.  As you may recall, I was planning on mounting spray rails.  I noticed some spider cracks in the hullsides (most likely from flexing around bad stringers).  I ground that glass out from the outside, only to find that the glass was very thin on the sides (and was mainly mat, with what seemed to be 1 layer of roven).  I then recalled JamesC telling me that he wished he had reinforced the hullsides of his hull (below the floorline) because he was getting gelcoat cracking from flexing around the chine.

So this lead me to my latest chore, which was to lay 3 layers of 1808 from the outside of the stringers up to the floor line.  Here are some pics:



You can see where I have ground the gelcoat away from the outside... it's the light areas.  The real pain is grinding the gelcoat out from the inside... they must have coated the hull with 2-3 times the amount that is on the outside.  





In the last picture you can see that I layed up a decent fillet with thickened resin (cabosil and fibers) before running the glass up the side.  
Now it's time to start fairing the outside, then mount the rails... THEN put the floor in.  

On a side note, I did go to TA Mahoney's over the weekend to shop for seacocks and plumbing... should start working on that soon too.

[JimCt]

Chine areas are prime spots for glass delam and failure because of the concentration of flexing stresses.  Add a failed stinger structure to the mix and and the hull starts coming apart.  Boats are symmetrical objects so you might want to do a thorough check of the starboard side chine area.  If you can't see any visual signs of problems, sound the area with light taps using a tack hammer.  Good glass will return a hard, clean sound.  Delaminated or cracked areas will sound a bit deader or more hollow to the tap.  If you do hear something a bit "off", now's the time to investigate further.

Stringer work looks great!  Your grandkids will thank you.

[damnitbadger]

Man, that's really coming together nicely. And I thought I had a major project going. LOL