Drive Train Construction
Remember I built the 13P with 2 engines. When doing this you do not need to slant the rear motor.
I mounted the motor back 3" from what the plans show. I also mounted the motor level. I did not have to mount at an angle because I did not send a belt to the front for lift.
This is showing the pillow blocks and 8" pulley for the thrust prop. The pillow blocks where positioned before I foamed the thrust duct to the hull. This made it fit perfectly with the center of the shaft. The plans are designed so that you most often have to add a spacer under the pillow blocks. This makes the system more adjustable. My spacers ended up at about 5/16".
Gas tank purchased at "Northern Handyman". It is a replacement for a long run generator. It came with two gas outlets, one for each engine. It holds 6 gallons of gas which will run both engines for 100 miles. It is set high enough to provide gravity feed to the front engine. The front engine will run out of gas if you run it to long while loading it on a slanted trailer.
The Gas tank fit because I made the rear of the cabin area 6" wider than the plans. This makes the supports that run back to the thrust shaft run slightly different than the plans. This gas tank/cabin width change was an excellent choice. It may not fit if you use a horizontal shaft engine!
Modification options...I have seen the thrust pulley to the cabin side of the shaft, or place it in between the two pillow blocks by cutting a hole in the support for the 8" pulley.. Both these changes require many other modifications.
I did not use the round wooden disk spacers for the prop. I attached the prop directly to the aluminum hub.
The wood disks you see next to the prop were not used. The prop shown is the first one I made and only has 3 - 3/4" boards.
The 42-36 prop requires 4 - 3/4 " boards.
Many people have been confused by the prop plans from UH. If you build the prop with 3-3/4" boards you can expect top speeds of about 30 mph with little performance getting over the hump! See the Prop page.
A view from front where the cockpit will be.
When positioning the thrust duct for foaming, make sure you leave the shaft in place in the hole in the center of the disk you used to make your duct. This will ensure that it does not move while your expanding foam sets.