JEM Watercraft

Mort,
I know the idea of using a larger outboard has been discussed before. Is it possible to carry the full beam out to the transom to help support a heavier outboard? I realize this changes to plans and probably the quantity of ply required. I like the overall design and would like to use a motor I currently own.
Marty

Sounds like an interesting idea. How large an engine would you use?

Basically I don't see any problems in making the boat parallel from midship and aft. It will of course be a different hull and you would change the properties of it, but that said you will also get the extra carrying capacity, you will need for the larger engine.

Jonathan and his son have built a 15' dingy and use a small seagull. Have you seen the new pictures of that nice boat? There is one picture where the boat is laying in the water with the seagull and when counting the seagull is not a lightweight outboard I think it is carrying the outboard well. However I expect you are looking for something heavier than the seagull

Morten,
Motor is probably around 85-90 lbs. Would the change be limited to the botom panel, transom and frames D & E ? I did see the pics of Jonathan's boat. Nice work. How would the handling properties be affected?
Marty

The changes will also affect the side panels since when you make the parallel aft ship you will have the shape of frame C continuing all the way to the aft. Only thing is you will need to make frame c higher the more aft you go to keep the sheer.

By changing the hull shape you will change the handling properties. One thing I will suggest is to apply a skeg. This will make sure you keep the directional stability.

Thanks Morten,
I think I will model the changes to see how it may look before cutting real plywood.
Marty

That sounds like a good idea to make a model first. You will then get a good feeling of the changes.