Custom rigger build

[larryrose11]

Hello all,
I had a rigger I realy liked. It was fast as hell. Because of an electronics failure, it caught fire.
I never took pics, but there is the sales page (http://forums.offshoreelectrics.com/showthread.php?23907-Fs-Ft-Custom-Built-Mini-Rigger-Lots-of-New-Parts).

I would like to re-create it!!
So, I’m in the initial design phase for a custom rigger, based loosely on the JAE Mini-sprint and the above design.
The general specs are:
- 19 inch tub
- 22 inch overal
- 12+inch wide
- Vaccine bag carbon fiber construction

The goal is to make it as light as possible, so I can go fast on small motors and such.
Im going to design it in CAD, and then use a CNC mill to make the molds out of wood.

Mt first line of questions is about construction.
How many layers? Fiber Orientation?

Another idea is to use foam core sandwich construction for the lower, and single ply for the upper.
Has anyone on here tried any of this stuff?
Randy (BBY) may know the answer to some of this stuff, if he is willing to tell me :smile:

[larryrose11]

OK, IM going to use this thread for notes too.
Construction on this build: http://forums.offshoreelectrics.com/showthread.php?38466-project-2013-124-the-very-last-HPR-233
they used 3 layers:
single layer of 163g/m² was glass
Carbon - Kevlar -220g/m² = 6.4886 oz / sq yard
Carbon Fiber - 245g/m² = 7.2259 oz / sq yard
ManuelW supplied the details

From Manual: @ Larryrose11: Mhh it includes a 245g/m² Carbon weave and a 220g/m² carbon cevlar weave but the exact number of layers and their order won't be shared here.

As for the look of this thing, im in love with the BBY Liftmaster, and the tub width may give me room for batteries.

[larryrose11]

Q: Rudder placement: Right on left?
Most designs I have seen have the rudder on the right. Why? Is it because the rudder is better on the inboard side for right turns?
I would think that if you have a turn fin on the right, a balance of a rudder on the left would be beneficial.

Q: Prop offset to the right: Some designs I have seen have the prop offset to the right when view from the back. I understand this to counter the dynamic effects of the prop.
http://forums.offshoreelectrics.com/...chmentid=86495
http://forums.offshoreelectrics.com/...chmentid=86494
http://forums.offshoreelectrics.com/...chmentid=86493

[larryrose11]

Here is an example of putting the prop on the far right side of the hull, and the rudder on the left side. The Team Lindeau EXECUTIVE
http://213.239.214.134/lindenau/cms/cms/upload/boote/executive800_2.jpg
I like this because you can use lengths of CF bar stock sticking out of the hull and bonded down the length of the hull on the inside to provide superior strength for the strut and the rudder.

[RandyatBBY]

Larry Hi I will help you as I can. I have about 1.5 hours left at the shop right now. I hav lots of work to do. I answer questions on my breaks and at lunch. I like to help. Done with my snack. by for now

[jcald2000]

Do not use that layup in your boat it's way too heavy, something like 4 oz layed 90,45,90. Three layers of 4 oz. will be more that enough.

[larryrose11]

jcald2000,
The notes in the above post are just that, a place to take notes.
Too heavy? Agreed
I was planning on using 3layers for the tub bottom /sides:
- 4 oz carbon weave
- 4 oz ineggra which has 3 layers of +/-45, and 0 deg carbon, all unidirectional
- 4 oz carbon weave.

For the top, I was going to use just 2 layers of 4 oz carbon weave.
I was going to use the sides as an overlap of the top and bottom, so the sides would have 5 layers.
Im using West systems epoxy with the 207 hardener.
I plan on vacuum bagging everything.

Im currently learning Inventor which is where Im designing it. I will CNC out a plug from the CAD.

I plan on using extenders, to avoid the problems of the boom getting in the way of the battery.
I dont plan on racing, just fun.

[larryrose11]

Randy,
Thanks a lot. Your designs and workmanship are inspirational. With any luck, I can turn something out that is worthy.
Im going to rely on this forum to help steer my design.

[RandyatBBY]

Are you going to vacuum bag?

[larryrose11]

Randy,
Yes. That's the plan.