20 MA project continues

jorgeinmiami · #1 02-05-2011, 07:55 PM

After Ken furnished me with a trailer I have gotten a 2nd wind and need to finish my 20MA.

To day I was inside the boat and noticed a soft spot in front of the console which I had not remembered was there.

Since I'm going to be painting the whole boat I want to do it once.

Measured out the soft spot and took a saw made the cut and peeled back the skin which I want to reuse.
Well the wood was wet.
Question why do they use small pieces of plywood and not just a large piece?

Well anyways the deconstruct continues.

Thanks Ken for making work today...

skin off
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Wet Wood

under skin

wood out

Fr. Frank · #2 02-05-2011, 09:40 PM

I think a Thank you to Ken a very appropriate response...

jorgeinmiami · #3 02-05-2011, 09:52 PM

that's been done

Islandtrader · #4 02-06-2011, 10:56 AM

Quote:

Question why do they use small pieces of plywood and not just a large piece?

Normally you would use smaller pieces of wood so that you won't have any voids under it and that it will be easier to level to the surface and or be able to crown a surface.

Think of it as the same way as tiling a floor.

Plus I think the mfg. wants to use up all the scrap he has...

Bushwacker · #5 02-06-2011, 01:00 PM

Quote:

Question why do they use small pieces of plywood and not just a large piece?

The late Moesly/early Potter hulls used balsa core everywhere except under the seats to minimize weight. I'm guessing Potter switched to plywood on the later boats to save $ as he was beginning to run into financial problems.

jorgeinmiami · #6 02-06-2011, 02:21 PM

Finished taking out the wet plywood and took a small electric chain saw and was able to take out some wet some dry wood all around the cut then finished the bottom of the cut out skin.

I imagine the replacement plywood needs to be coated in resin 1st and on the bottom that faces down use additional resin to get a bond.

How far do I need to grind around the edges when I lay down the skin?

Pics to follow

Thanks

jorgeinmiami · #7 02-13-2011, 02:41 PM

Put boat on trailer to see how it sat on it and it looks pretty good. Took the fenders off and am going to get the cross members replaced. I also need a jack for the front

I know it's a pain to take the boat off again, but I could not wait to see how it looked

AGAIN THANK YOU KEN!!!!

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McGillicuddy · #8 02-13-2011, 04:17 PM

Quote:

Question why do they use small pieces of plywood and not just a large piece?

In addition to Terry's points, the use of smaller pieces also eliminates undesired warping or cupping. This would be most significant if one were to use inferior grade ply full of knots, voids, and non-waterproof glues. If you'll revisit Strick's "I need a shrink" thread, you'll note how Strick took it a step further by actually leaving gaps between the wood squares and filling the voids with his resin mix, effectively sealing the end grain of the wood pieces.

Boat looks good on a trailer, Jorge.
Just one note - you might consider setting/stacking the cinder blocks so the holes face the ground and sky. Much stronger/safer that way.

jorgeinmiami · #9 03-27-2011, 01:58 PM

Well after a too ong of just seeing the boat in the driveway and all the really nice days I picked upthe project again.

I cut some 5x5 pieces of ply and taking advise from Strick's project leaving spaces in between the squares I used a thickened mix in between them.

If you see anything I may have done wrong nows the time to let me know.....PLEASE

Have to go run some erands with wife so later in the after noon I plan on replacing the skin.

I'm close to closing on a town house in Islamorada and I want to have the boat for use down there.

I hope once I get down there if there are any of you guys down that way I hope you drop in. With a special invite to Ken
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gofastsandman · #10 03-27-2011, 06:39 PM

When a noob gets a job at a yard they make him cut sheets all day long, every day. Then he gets to clean out the dumpster.
If he still shows up, they may hire you.

End grain balsa can localize intrusion.

You`re using poly right?

Ideally, the bevel is 12 to 1. 1/4" = 3 ". Try to make an accurate ramp when beveling. Fill with small pieces of glass going bigger as you fill. Another ramp if you will.

For the raw core I would flash coat it first. Mix the poly and when it gets warm cut it w/ acetone `till the consistency of milk. It will really soak in and give you good tooth for the glasin`.

Cheers,
GFS