The Donald David, a Maine Lobster Boat, launched 1956

Good morning, all. I am starting to get back into the workshop now. I spent some time cleaning up the shop and I am almost ready to cut slots in the plywood jig that will hold the molds in place for planking. The plywood jig also holds molds #1 thru #10 in place so I can refine the shape of the stern.
Happy Modeling.
Steven
 
Much to my surprise, I have finally carved the rabbet on starboard side of the keel. Port side is patiently waiting for me to finish the rabbeting! Hopefully I will get through it this week. It took me a long time to muster up the courage to do such carving. Moving forward should be easier now.
Happy modeling.
Steven
 
SAHaskell said:
Much to my surprise, I have finally carved the rabbet on starboard side of the keel. Port side is patiently waiting for me to finish the rabbeting! Hopefully I will get through it this week. It took me a long time to muster up the courage to do such carving. Moving forward should be easier now.
Happy modeling.
Steven
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Hallo Steven,
we all hope to see some photos of your progress.....
 
Sooo, as I am looking at the keel & temporary bulkheads for the lobster boat, I am wondering about adding extra planks in the forward portion of the boat because if the high-rising bow. I shouldn't need many because of the horizontal planks at the stern twist about 90 degrees to attach vertically to the stem. But I need to figure out how many extra planks will I need to fill the forward height and from what point in the length of the hull do I start these extra, tapered planks?
Any thoughts & ideas are greatly appreciated.
Happy modeling.
Steven
 
Thanks. It has only taken me about 30 years to get this far. My original plan was to build this with my son when he graduated from high school, but he died in his senior year, so the plan got tabled for far too long. It feels good to actually be making some headway now.
Happy Modeling.
Steven
 
SAHaskell said:
Thanks. It has only taken me about 30 years to get this far. My original plan was to build this with my son when he graduated from high school, but he died in his senior year, so the plan got tabled for far too long. It feels good to actually be making some headway now.
Happy Modeling.
Steven
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After such a loss it's great to see you've found the courage to continue with this build. You have my deepest sympathy.
 
SAHaskell said:
Well, I am mostly recovered now. Should find out from the doctor tomorrow just what was the cause of the stomach ailment. That may, or may not, result in some medication to ensure no relapse. Good news is that I'll be able to spend some time making sawdust. Can't expect too much, though, because my wife & I are going to Portland Oregon area for about a week of sightseeing. Our daughter, in Bonney Lake, WA will be driving to Portland with her 4-month o;d baby to spend a few days with us.
But none of that has anything to do with model boat building. To cover that base, I have a question about sourcing & sizing an electric motor to drive the propeller for my lobster boat build. I have the impression that it would be practical to use a motor with a 2:1 speed reducing gear for better efficiency since this is not a race boat. I am more interested in realistic speeds with good control and minimum over heating. Any recommendations for motors and/sources of info about motor options? Any help is greatly appreciated.
Thank you.
Steven
PS: Ideas for batteries and chargers would be very helpful as well. :)
Forgot to include Propeller info: 1 1/8" dia. with about 1.3"pitch. Drive shaft is 5/32" dia with #8-32 machine-screw thread on propeller end.
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Nice project Steven,
If you haven't made much progress with what motor, battery and maybe which radio to use, then maybe I can help a little bit.
You are quite right about the 2:1 reduction. This may also help with mounting the motor closer to the end of the prop shaft. I say that because it looked like there is very little clearance between the keel and prop shaft where it enters the inside of the hull, you can get around this with a long coupling or gear/belt reduction.

Leading questions would be; What is the budget, Brushed or Brushless motor (either will be fine), Battery being a displacement hull any thing from a Gel cell, Ni-MH to LiPo or the much safer LiFePo4.

A lot will depend on what you are comfortable with.

One question is what is the overall weight of the model, I think the length is about 25 inches.

Cheers,
Stephen.
 
Thank you for your comments, Stephen. They are indeed helpful and appreciated.
The model is 24 1/2" stem to stern. The real boat was 34' long. I have no clue about weight of my model yet. The only info I have about construction is the half-hull model that Bill West used to build 3 lobster boats in his lifetime. Bill's father used it to build an unknown number of lobster boats. I purchased a set of lobster boat plans from the Maine Maritime museum and I bought a book about building full size lobster boats. Both of these provide helpful insight for my model construction. The building budget is not fixed at any set value, I'll just keep building as well as I can.
Bill West told me that the real Donald David was built 4 feet wider than what the scaled up half-hull would have come to, so I have done the same for the model I am building (at 1/16" = 1ft).
It will be a while before I get to the point of buying the running gear, but I do sometimes look for sales that might prove lucrative.

Again, thanks for your helpful comments.
Happy Modeling.
Steven
 
SAHaskell said:
Thank you for your comments, Stephen. They are indeed helpful and appreciated.
The model is 24 1/2" stem to stern. The real boat was 34' long. I have no clue about weight of my model yet. The only info I have about construction is the half-hull model that Bill West used to build 3 lobster boats in his lifetime. Bill's father used it to build an unknown number of lobster boats. I purchased a set of lobster boat plans from the Maine Maritime museum and I bought a book about building full size lobster boats. Both of these provide helpful insight for my model construction. The building budget is not fixed at any set value, I'll just keep building as well as I can.
Bill West told me that the real Donald David was built 4 feet wider than what the scaled up half-hull would have come to, so I have done the same for the model I am building (at 1/16" = 1ft).
It will be a while before I get to the point of buying the running gear, but I do sometimes look for sales that might prove lucrative.

Again, thanks for your helpful comments.
Happy Modeling.
Steven
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1666195815780.jpeg
Hi SAHskell, sorry that I sneak into your yard, for the engine see this engine
 
SAHaskell said:
No need to apologize.. I look forward to all comments. My father taught me that "you can learn something from every person that you meet." That is a nice looking motor. Where can it be purchased?
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Thank you, in truth I have no idea, they are engines of the Decaperm bought many years ago, I look for a bit and I will let you know, good 1666197356647.gifThank you, in truth I have no idea, they are Decaperm engines bought many years ago, I'm looking for a bit and I'll let you know, good evening, 2 are mounted on this 15 Kg model,
 
Hi Steven,
As Frank has pointed out a Decaperm would be able to do the job, nothing wrong with those motors they were highly regarded many years ago, the main drawback is cost as these motors are quite expensive.

One option I would recommend is a 385 brushed motor like this one.

https://microdcmotors.com/product/2...que-used-for-electric-tool-electric-machinery

This is a higher torque lower revving version of a 380, these are low cost and have enough torque to push your boat. I have a 385 driving a 1/72 scale Flower class corvette direct drive, driving a 1 1/2" diameter 3 bladed prop. The speed controller can be a car type giving you forward and reverse, my boat has a 7.2 volt 3 amp hour NiMH battery pack and easily runs for 1 hour or so on a charge.

Another option is a brushless Outrunner, something with a diameter of around the same as your prop and having a low Kv rating will also do very nicely as well.

Cheers,
Stephen.
 
Stevedownunder said:
Hi Steven,
As Frank has pointed out a Decaperm would be able to do the job, nothing wrong with those motors they were highly regarded many years ago, the main drawback is cost as these motors are quite expensive.

One option I would recommend is a 385 brushed motor like this one.

https://microdcmotors.com/product/2...que-used-for-electric-tool-electric-machinery

This is a higher torque lower revving version of a 380, these are low cost and have enough torque to push your boat. I have a 385 driving a 1/72 scale Flower class corvette direct drive, driving a 1 1/2" diameter 3 bladed prop. The speed controller can be a car type giving you forward and reverse, my boat has a 7.2 volt 3 amp hour NiMH battery pack and easily runs for 1 hour or so on a charge.

Another option is a brushless Outrunner, something with a diameter of around the same as your prop and having a low Kv rating will also do very nicely as well.

Cheers,
Stephen.
Click to expand...
Thanks for all the good advice. I really appreciate it. I copied the motor info into my computer file for this build so I won't lose it later.
 
SAHaskell said:
Thank you for your comments, Stephen. They are indeed helpful and appreciated.
The model is 24 1/2" stem to stern. The real boat was 34' long. I have no clue about weight of my model yet. The only info I have about construction is the half-hull model that Bill West used to build 3 lobster boats in his lifetime. Bill's father used it to build an unknown number of lobster boats. I purchased a set of lobster boat plans from the Maine Maritime museum and I bought a book about building full size lobster boats. Both of these provide helpful insight for my model construction. The building budget is not fixed at any set value, I'll just keep building as well as I can.
Bill West told me that the real Donald David was built 4 feet wider than what the scaled up half-hull would have come to, so I have done the same for the model I am building (at 1/16" = 1ft).
It will be a while before I get to the point of buying the running gear, but I do sometimes look for sales that might prove lucrative.

Again, thanks for your helpful comments.
Happy Modeling.
Steven
Click to expand...
One more thing Steven with regard to scale, there seems to be an error in my opinion.
If your boat was 1/16" = 1' it would only be 2 1/8" long, your model is closer to but not quite 1/16th scale which is a metric scale.
I can go into more detail if you would like.

Cheers,
Stephen.
 
You are absolutely right, Stephen, it's not the first error I made this year. They sort of sneak up on me when I least expect it. The scale is 1/16th, resulting in 3/4 inch = 1 scale foot. The original boat was 34 feet long. Thank for catching that.
Happy Modeling.
Steven
 
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