Who wants to build a semi-scale all-wood micro hydro?

[JimClark]

Is Jim Stevens doing the DLP printing? That is looking very good. How durable is it in a wet enviroment?

[Dr. Jet]

Jim Stevens does FDM printing and did those motors for me shown in post #139. The DLP motor in post #180 was actually done by laser guy #2. While his laser has some shortcomings, his 3D printer more than makes up for it. 100% waterproof and lighter than FDM because they can be made hollow. With really cool 1:20 engines available, the basic Atlas hull will do at least a dozen other boats (mostly exposed engine) from 1972 through 1983.

Now, I have to convince him to do an Allison.....

[old guy]

30 more days lol till we can order

[Dr. Jet]

30 more days lol till we can order

That's what happens when you have to depend on others....

Actually, you can order one today,......... It just won't ship until 30 days.

Atlas kits are ready to go!

[Dr. Jet]

Equipment Layout

Here's the layout. Note small bends in the rudder pushrod.

[Dr. Jet]

1:20 scale Merlin

This is what it looks like before trimming off the supports.

[Dr. Jet]

Found an Allison

https://www.turbosquid.com/3d-models...-engine/370280

It wouldn't be difficult to edit the file such that the exhaust was going the other way. While not as precise as the Merlin, at 1:20 scale it would look just fine in one of my little hulls. As you can see, the file is not cheap, so it would have to be worthwhile to buy it.

That said with the two hulls I've done, a person could build dozens of different boats. The secret one I have in the works was a large boat at 32' so it may only do the one hull. Instead, I may do a Karelson hull which would open up countless more options.

[Dr. Jet]

Driveline Completed

OK, here's the completed 1/32" wire drive. The majority of the driveshaft is actually 1/16" stainless steel tube, but the 1/32" wire runs full length from the stubshaft to the motor coupler. It is only where the driveshaft exits the hull to the nosecone on the strut that the 1/32" wire is exposed to allow a gentle curve in the driveshaft.

[Dr. Jet]

I found a driver figure to 3D print at 1:20 scale

A bit more modern, but it will work with most 1:20 scale boats with some tweaking.

[Dr. Jet]

Well, all the design work for Short Circuit kits is done. Boxes are being populated with parts and all that remains to add to them are the laser cut wood and copying the instructions to a CD. The laser guy is on vacation but I should have it all cut by April 15th at the latest. Burning the CDs is a matter of 20 minutes. I have an idea I thought I would throw out there. I now have the ability to 3D print a Rolls Royce Merlin, an Allison V-1710 and a couple of different driver figures in 1:20 scale. That opens these two kits into making dozens of different hulls. Making the kits 100% complete was a bit of a PITA, and I don’t think I will do it again. Furthermore, I don’t think it was necessary to cut and supply all the balsa parts; most builders should be more than capable of cutting out those parts from sheet stock. It is the intricate and precise-fitting plywood parts that really benefit from laser-cutting.

So here’s my plan from here on out: I’m going to produce “Short Kits” ONLY, and only on demand. They will be just the laser-cut plywood and paper templates for the balsa bits. No information will be provided for the cowls since there are so many variants. I will be able to include scale engines and driver figures by special order. Everything else will be up to the builder.

I could do a 1:20 scale Karelson hull that would do at least a dozen other boats as well, provided there were enough interest.

[Dr. Jet]

First DLP Printed Driver and Engine

Here they are.......

[Dr. Jet]

3D Printing

Well, I have the 3D printed Merlin and driver figure in hand and they look great. The only problem is they're too big. I'm going to reduce the driver to 85% of his current self and will work out a reduction figure for the Merlin when necessary. Mike printed the driver as one piece, but the files were separate arms, head, body. and steering wheel. I'm going to have him printed in parts so he can be posed better. I always like the head tilting a little left or right and looking off to the side. I think it just looks better like that.

[Dr. Jet]

Posing the Driver Figure

This is what I mean about posing the driver figure.

[JimClark]

Looks great very good detail. What about weight?

[Dr. Jet]

Looks great very good detail. What about weight?

They're hollow on the inside so weight is minimized, but they're still a bit hefty. I'll give you an exact weight later.

UPDATE: My electronic digital .01 gram scale died. I guess I can use the triple-beam and get .1 gram accuracy. Please Stand By.........