Scratch cat V3... XCat

[Jesse J]

Had my buddy cut me a motor mount plate and got the drives mocked up

[Jesse J]

Motors are glued in, stuffing tubes in and escs wired!

[jingalls007]

Oh man it’s getting close!!

[Jesse J]

Ya, getting close. Need to figure elegant water pick up, clean motor access hatches and then seal her up.

After all the struggle and still barely convinced I’ll have cog adjustability, I’m having version 4.3 cut.. the sixth revision in 4 months.
Next version mods are to allow getting weight farther back easier.

Gonna call this design the “Wolverine X”. Possibly scale up to 48” and down to 17”. Once tested in battle, then into production.

[properchopper]

This will be the coolest boat anywhere Perfect proportions fer sure

[Jesse J]

Thanks Tony. Would you be up for testing a mlb prototype kit for me?
I’m working with mike and wanna have some key Fe racemasters test the build and performance of this guy.

[properchopper]

check yourPM box

[jevmax]

Very innovative Jesse. Good job!

[Jesse J]

Why thank you mr. Legend! You saw v2.. the big one that needed twins to wins. This one ought to bo better.

[Shooter]

Hot Damn!!! Love those outboards!!

[Shooter]

I personally would send the cooling output back into the outboard motor housings and then out the sides for a scale look, but then again, I'm nutz! :) The tubing going into the outboards would serve as the 'fuel' lines. :)

[Jesse J]

This update will include success (as well as failure) learnings, which are as important as failure learnings but wayyy mo satisfying!

Failure:
1) ensure you will have cog adjustability between 25-35%. This version does not have the physical room to put electronics far enough back (thus the twin outboards and all the stupid hatches).
2) ensure you have logical steering rods exit points. Still working on this one...
Modification to next version: move the steps and point of inflection where deck really swoops down backwards and increase transom height from 1/2? to 1?.

Success:
1) no balsa! 1/16? ply is way faster to finish than balsa and fiberglass. Shape sanding with 80 grit then 150 then 220.
2) black dyed west systems sealant. This allow you to know when you have removed enough epoxy and it?s time to fill any depressions with bondo. Sanding started with 220 then 320 and 400 dry sanding.
3) wet sanding rules! I used all duplicor paints. For primer, I started with 400 dry, then 600 wet to get super smooth. After second coat of primer, I finished with 1000 grit wet sanding. Even after the black and clear, I hit it with 1000 wet sand. Final coat of clear I left alone.
Pics to come..

[Jesse J]

571DB458-8F5F-4456-8735-7F4F055650DB.jpg37065E0F-2F41-4711-83E0-BA8F48F79793.jpgD4CD8DBB-6143-405F-B476-78E7BE9A30EC.jpg759D834F-7358-4459-95FC-0B2C7E22B136.jpg4E9602EE-2972-49FB-9D32-B2CAF53B8DED.jpg

[Jesse J]

Primer and bla-poxy on the hatch.

[Jesse J]

This was all done outside in temps above 60deg F.
Graphics are modified from internet findings and cut on my vinyl cutter.
I still plan to paint canopy silver... it is black-poxy in these photos.

[Jesse J]

On the bottom, there is tons of cf plate. For water intake, I?ll try these streamlined intake doodads from Ose.

Last “design-as-you-build” item is the steering system... stay tuned.

[Shooter]

Beautiful! ...and I love the "guide coat" idea with the black dye.

[Jesse J]

Here she be.. maybe she gets wet soon?!?

[Jesse J]

And two more.
All duplicator paints.
Primer,
Black pearl,
Silver on canopy,
Metal flake clear and
Clear top coat.

My own graphics - I did modify the Wolverine image and used the X-men Wolverine W..

[1coopgt]

That came out really nice Jesse. Can't wait to see a run video.

[jevmax]

Looks great Jesse!

[properchopper]

If there was a contest for the most creative, coolest looking rc boat ever, this one would win, hands down

Can't wait to see the vid

[Jesse J]

Dang, thanks for all the kind words!
And here is the maiden voyage..
got some tuning to do, but who wouldn't expect that?
these out-drives are a little squirrelly (as expected) and I may try some kind of keel or turn fin.
No tunes, but the music from twin power should be sufficient, if not better!

[1coopgt]

Interesting how it spins out in the turns if you cut it hard. Learning questions. What causes that? Is the bouncing on acceleration from weight distribution.

Usually my boat just does a backflip as it starts to get some real steam going. LOL

[Shooter]

Looks great! I love the paint scheme. Imagine 6 of these things in a race! I had a design that hooked real bad and it ended up being too much dihedral. I'm not an expert though! Just my two cents. I bet the skeg will work. Works well on ski boats!

[Fluid]

Jesse, I?ve seen a lot of this behavior, but it was years ago when we raced RTRs in the Anchorage pool. The problem is a combination of steerable outdrives and tight turns. The vectored thrust pushes the transom out when the bows dig in on slow tight turns, causing the spins. The solution is to limit the steering angles and don?t make such tight turns. Scale the boat up and the speed and sharpness of the tight turns would throw the people out of the boat! Outboard tunnels which had this problem used stumble blocks in the tunnel to help keep the bows up. They are visible inside the tunnel near the bows in the photo below.

It certainly is an awesome-looking cat, I?m glad you went twins. Any ackerman dialed into those OBs?




.

[properchopper]

I found, like Jay said, that steerable outdrive(s) , especially when I got into outboard tunnels, causes that spinout behavior. I experimented with (to some avail) with a servo slow-down module. Then basically carefully set the servo endpoint(s) to just where a lane 2 turn was at. Of course some better radios offer this servo speed calibration option - mine didn't .

I also actually elongated the fin on my Hyperformance lower unit but I lost the pictures when I transferred my pics to my new cormputer

[Jesse J]

Yesss.. steerable “spin out” drives! I recall from my intro to ~FE: the graupner electrovee!
Can’t say I was surprised.
So I have dialed back steering to 60% and am stumbling a little on the dimensions of Jay’s stumbling blocks. Still brooding on skid fins..
Ideas? Depth, width, angle, etc?

As for running wet: Turns out I have outdrives kicked up to max without shimming the mount... sooo as Jay commonly recommends: prop up.
I have prepped my cnc 4614/3 blade props (up from 4416/3) detongued and sharpened.

Cold days ahead so hoping for updates this weekend.

[Fluid]

Jesse, the stumble blocks/tunnel ramps are meant to help keep the bow up in turns. I used them on strut-driven cats in the 90s when power was much lower than today. The bottom of the ramp was usually between 1/8? and 1/4? above the sponson keel and 1-1.5? wide. They didn?t touch the water at speed, only in slower turns to carry the bows and reduce the chance of hooking. I got the idea from my friend Jerry Dunlap, a boat designer in the late 20th century. Here is one of his plans.

[Jesse J]

Sweet, thanks Jay!
Scale? Do you know the length of that boat, so I can approximate those dimensions?
Thanks buddy, I can’t wait to test!