A technique i learned that might be useful in working on your boat

[Vincentc]

I recently started construction of a kit model boat. The Dumas American Express offshore supply boat. It is an interesting kit with lots of pre-cut wood parts, many, but not all of which fit just fine. For instance the hull panels are oversized and require quite a bit of cutting.



I struggled with cutting the 1/8" plywood to fit, and then it hit me to make patterns using masking tape. I laid the tape down to conform to the needed shape.



I then applied the tape to the wood panel



I used the table saw with the blade low to cut the panel to the shape of the tape.



I believe this use of masking tape patterns should be useful working on a real boat when you need to cut a piece of wood to fit an odd sized space.

Regards,

 

[Vincentc]

Here is the hull with the last hull panel in place.



One other thing I learned was one way to mix very small batches of 2 part epoxy. Small paper cups and a digital scale measuring in grams. The epoxy I use is a 2 to one ratio. I pour may be 12 grams of resin then add 6 grams of hardener, then mix with a tongue depressor. Really cuts down on waste.

 

[Avenger]

Great suggestions, and nice project. Thanks for sharing that.

So what are you gong to use for power? Back in the day they usually had triple 12V-71s. Just a thought.

 

[holtcl]

I LOVE the digital scale tip-- I use the small paper cups when mixing mini-batches of awl grip for small jobs with multiple coats or touch-ups. Had not thought about weighing the material!

Thanks for sharing!

Cheryl
Cinderella
1971 53 MY

 

[Vincentc]

Regarding Mixing by weight vs volume.

For those of you who are extremely scrupulous; the ratio by weight is slightly different than by volume. For example for Raka brand, which I use, the ratio is 43/100 by weight vs 1/2 by volume. I cannot say whether using 16% more hardener than called for makes a difference. It only takes a little effort to make up a table with a spreadsheet to mix at the correct weight ratio.

Other epoxy brands may have different mixing ratios. An internet search should tell you the correct ratio by weight for your brand.

Obsessively Yours,

 

[oldawg]

So what are you gong to use for power? Back in the day they usually had triple 12V-71s. Just a thought.

The boat was actually the American Enterprise. Built as a test bed in time for the 1976 bicentennial of the US by Halter Marine in Chalmette, LA (suburb of New Orleans). Really advanced for the time it was powered by a centerline gas turbine water jet and two outboard conventional Detroit engines. 101' and fast but way before it's time.

 

[Vincentc]

Greg,
Thanks for correcting the name. I guess I thinking about how I paid for the kit.
Interesting you should note that AE was a test bed for Halter. I bought the model with the intent of using it as a test bed myself thinking I would experiment with ways to trick the waterline length and increase Lilly Marie's effective hull speed. I made that plan before appreciating the magnitude of hull alterations to a 43 foot boat. To answer Scrod directly I do not have any plans to power the model. The learning curve to install electric motors and remote controls strikes me as too steep.
Regards

 

[Avenger]

The boat was actually the American Enterprise. Built as a test bed in time for the 1976 bicentennial of the US by Halter Marine in Chalmette, LA (suburb of New Orleans). Really advanced for the time it was powered by a centerline gas turbine water jet and two outboard conventional Detroit engines. 101' and fast but way before it's time.

Interesting. Thanks.

I don't know if there ever was or will be a time for gas turbine powered boats in any field except racing or just showing off how much money one has to burn.

 

[oldawg]

Interesting. Thanks.

I don't know if there ever was or will be a time for gas turbine powered boats in any field except racing or just showing off how much money one has to burn.

While there doesn't seem to be much market for turbine powered boats (save perhaps the military), the water jet idea was in it's infancy as well and has gone on to become quite common. The reason for using gas turbine in those days was horsepower to weight ratio. Imagine getting a 100' boat on plane with deckload and fuel. Much easier with modern diesel power. There are crewboats in the 200' range now that can run at 25kts plus.


http://www.seacormarine.com/pdf/190_Crew-FSV_Aaron_S_McCall.pdf

 

[Avenger]

The reason for using gas turbine in those days was horsepower to weight ratio.

That's the only justification that exists anywhere for gas turbines.

Don't get me wrong, turbines are amazing. But even with the price of fuel back then they were pigs.

That Seacor boat,... kind of fits the profile of a lot of the OSVs from days gone by. Lots of small engines running on the pins instead of a couple of larger (and more expensive) plants making the ponies. It's probably about packaging and purchase price vs. durability and operating cost.

 

[Seabrooke]

Nice work Vincent.

Well done on using the tape to work out the correct shape.

That is one method still used on occasion in building full size wooden boats too. I have used rolls of brown packaging paper for the purpose.

Here's another tip for cutting the ply.

For small jobs - even large pieces on occasions - I generally cut anything less than 6mm (1/4" for you guys ) with a good quality Box Cutter (what we refer to as a Stanley Knife) for perfect cuts with perfect edges. You start with light score marks then cut through following those lines. I have even used those to make small cuts in Mahogany strips when less than 6mm thick.

Practice this a little first on some scrap and soon you'll find the joints on your model reaching perfection.

 

[Vincentc]

Rick,
I had tried a utility knife but not with repeated scoring.
Thanks