1983 Invader Floor Repair Support Needed - Take 2

[Rickmerrill]

Oops, Wood and I were typing at the same time so I think I know who you should listen to...

 

[Woodonglass]

Yeah, I think you should LISTEN to your "GUT" and NOT some Old Dumb OKIE that goes around tellin everyone how to do stuff!!! Bottom line...it's you're boat and you should do it the way that makes sense to you. It Ain't brain surgery and it'll pretty much work out just fine no matter what you do!!! Look how BAD the factory did some things and look how long it lasted!!!!:faint2:

 

[PitaBoat22]

Excellent point, Wood, and perfect timing for your comment as I am sitting her sweating over getting the stringer placement perfect. The shirt doesn't read "Backyard Piano Builder" so 1/16" here or there really shouldn't matter much.

Here's what I am thinking of doing to get the stringer height right. I'm going to mark the hull to show the outline of where the stringers will be. I will then place a piece of wood, say a 1 x 4, across the hull to represent the height of the deck. I will place a piece of quarter-inch foam board on each end of the 1x4 to represent the space that will be between the deck and the hull that will be filled in with PB.

Starting at one end and following the lines showing the stringer placement, I will measure the distance from each of the lines drawn on the hull to the bottom of the 1x4. I will then move the 1x4 a distance of 1 inch and take the next set of measurements. I will do this every inch until I get to the other end. Since the hull is at an angle, I will take measurements from the highest line and the lowest line for each stringer to the 1x4. This process will be repeated for the stringer on the other side of the boat as well. Assuming a stringer length of 11 feet, that will be 132 measurements for the highest line and another 132 for the lowest line, so 264 per stringer.

Given each stringer will be raised up a quarter inch from the deck and the glass covering the top of each stringer will take up another 1/16 inch, I will subtract 5/16 from each measurement.

I will then use these measurements to draw up each stringer.

I would just rather do what I can to avoid cutting the stringers to height after they are PB'd in place. I think this is how Frisco did it and I am just not as excited about going this route.

Thoughts?? Cautions???

 

[PitaBoat22]

A little delayed in getting this last video update posted…..

https://www.youtube.com/channel/UCNf...GB0AlkTszgdXGg

 

[Woodonglass]

Ok, Here's how an Old Dumb Okie would do it. Duct tape a ledger board on the sides of the hull so that you can lay a 3/4" 1x4 across the hull side to side and slide it along from the transom to the bow. You can use a tape measure at 4-6 inch intervals to measure from the bottom of the 1x4 to the hull. That's how this Old Dumb Okie would do it!!!

 

[kcassells]

http://www.youtube.com/watch?v=-iYY2FQHFwE

 

[Woodonglass]

YeeHaw!!!!

 

[PitaBoat22]

There goes Merle laying it DOWN!

 

[PitaBoat22]

Hey guys....quick update. Completed height measurements for my stringers and cut them out this past weekend. Also fabricated three stands for each of them. Next step wlll be to get the gaps in the plywood filled with PB and dry fit everything in. Hope to get to some of this this weekend. Will post pics soon.

 

[Woodonglass]

I Highly recommend to fabricate a Stringer spacer/Placement jig. Mine looks something like this...

Once you determine the proper spacing use a 1x4 and rig it up to hold them vertical and spaced properly. C-Clamps or Pony Clamps work well to clamp them. It worked well for me any whoooo!!!

 

[PitaBoat22]

That's very similar to what I fabricated. Pics coming soon. Was going to work on it today but 18-yr-old water heater needed emergent replacement so spent the day doing that. It's always something! Keeps me on my toes.

 

[PitaBoat22]

Ok - made my first small batch of PB using polyester resin and cabosil. Looks like I didn't pick up any quarter-inch chopped strand glass, so didn't use any for this batch. I was only using it to fill in any gaps in the plywood being used for my stringers and bulkheads, so I imagine the PB I made will work just fine. I will be picking some chopped strand glass before I make PB for laying in the stringers, etc. The instructions on the poly resin container indicated a resin-catalyst ratio of 1% to 2% by weight or 10 mL of catalyst to a quart of resin for a 1% ratio. I went with half a quart, 16 oz, and 5 mL of catalyst. Anyone see anything wrong with that? This made a lot more PB than I needed. Definitely need to wear the respirator.

 

[Rickmerrill]

Nothing wrong with that.

You'll find working by volume and the metric system is very close for the amounts we use.

Do they give any info for small batches like drops per ounce? There will be times when you only need an ounce or two.

 

[PitaBoat22]

No, they don't, but I can just do the math I suppose.

 

[Woodonglass]

It's much easier to use metric. A quart is approx. 1000 ml. So you'd use 100 to 150 ml of MEKP per 1000 ml of resin. Makes things real easy. I start with 1500 ml of cabosil and then add more if needed. This usually works great for me. Just cut it in 1/2 for small batches.

 

[studioq]

Do they give any info for small batches like drops per ounce? There will be times when you only need an ounce or two.

This is what has worked for me when it comes to small measures - I usually only do 2oz at the smallest.
Plain resin (no cabosil) - 10 drops per ounce for nominal set time at 70 degrees. 5 -7 drops per ounce for long gel times.
Thickened Resin (PB) - 10 drops per ounce for longer than normal set time. 15 drops per ounce for shorter (30 to 50 minutes)

With PB - once you step up to cc's (same as mL) - 7.5 to 10 cc per half quart of liquid resin for longer set time (1 to 1.5 hours) and 15 cc's per half quart of liquid resin for faster (30 to 45 minute) set times.

These are for cooler temps... 70 to 75... For summer you would have to tune those back a few cc's to keep things from getting messy.
Essentially - when you're working with thickened resin it's very hard to make many mistakes other than adding too little MEKP and having it take forever to kick or not kick at all... When you add the cabosil you can add a level of MEKP that would make plain resin go off really fast. The addition of cabosil really slows the reaction time a lot. So if you're on a tight schedule and need to keep moving don't hesitate to use the high end of those numbers in PB.

At least that's my 2 cents...

 

[PitaBoat22]

Getting darker earlier and getting a little cooler so harder to get at it. That said, I did try to gain a little ground today by dry fitting the stringers. Had some difficulty, so I think I'm going to try a different strategy to get them spaced correctly along the entire length. I might not get to it until the week of Thanksgiving as I'll have the entire week off. Didn't want you all to think I've abandoned my project.

 

[Rickmerrill]

The thought never crossed my mind.

 

[PitaBoat22]

Well, here we are....my week off. Starting to get ready to make a significant push on the boat re-do. Should have stringers & bulkheads ready for positioning by Monday. Question - I will be bedding the decking material in PB around the edges but I am wondering how to attach the decking to the stringers. I know they used large staples originally, but I don't want to do that.

 

[Rickmerrill]

Glue and screw. Glue being PB, screw being SS wood screws. Countersink for screw heads. Most use resin or 5200 on the screws. You can attach cleats to stringers to screw to if you want.