New Twin Cheetah build

[royalcasa]

Transom reinforced with two layers of 1.5mm coremat, hard angles filled with thickend epoxy, all seams under the deck have been reinforced with 4” CF, inlay done. Sponson nose filled with epoxy. Motor mounts,servo
Mount and stuffing tube supports done. 8AB8B8EF-271C-45A5-8F58-2BA59B91909C.jpg8B432B9E-9BCB-424C-95AA-4F7002B7DD05.jpg2F51350A-D4CF-4928-94B2-7E5068505554.jpg38350C97-C879-4579-9C1A-C66FF2E9CED1.jpg

[Prodrvr]

Great start

[785boats]

Great start indeed.
The hull seems to have anti gravity properties. An unfair advantage, methinks.
But seriously, looking forward to the progress on this build.
We have a few Cheetahs racing at our club. Not many twins though.
Any ideas on motors & props at this stage?

[royalcasa]

Hardware

ESC. Seaking 180 V2
Motors 4050 2310
Stingers MTC
Rudder Speedmaster
Servo low profile Sevox
Props 447 2 blade by Andy Brown
No spark connectors from OSE

I opened up the water lines in the rudder as much as possible, I also bought the cooling jacket that would be for the 4060 TP it fits perfect on my 4050. Trying to do what ever I can to make it run cooler.

66748D23-D226-4923-8AAC-229005781428.jpgF593C58D-86D9-48E5-A8D0-F7F5317F437E.jpg4204EB94-D7CC-4946-B7FD-403D05A1C551.jpgF1C5227B-9CC1-47CF-8C79-CCB329C72522.jpg

[Prodrvr]

Does that Coremat actually add that much rigidity to the hull?

[royalcasa]

It does once it’s soaked with epoxy and dry. The area were the stingers will be mounted are about 1/4 thick and it’s hard, Some use a piece of CF and that’s fine to

[NativePaul]

Does that Coremat actually add that much rigidity to the hull?

If it is used as a core, to space 2 materials with high tensile strength appart, then yes hugely.

As it has a very high compressive strength it actually does better in areas with bolts passing through it, than more modern cores that offer much better stiffness to weight ratios.

With only one side of it covered, not so much, it has added 3mm of resin on top which will certainly give extra stiffness, but it will be a fraction of the stiffness that would be gained for the same weight, by using 2mm coremat and putting a few layers of glass over it.

[Prodrvr]

Oh ok. What I do is where the rudder and drives are mounted, I fit a piece of 3mm cf sheet and epoxy it in.

[785boats]

I guess I'm old school;
I epoxy in a piece of 3mm or 4mm aluminium plate. Then drill & tap the hardware on. No need to fiddle about in confined spaces with nuts & washers.

[Prodrvr]

I guess I'm old school;
I epoxy in a piece of 3mm or 4mm aluminium plate. Then drill & tap the hardware on. No need to fiddle about in confined spaces with nuts & washers.

How big of a piece? That sounds heavy.

[785boats]

Heavy? No mate.
The same size pieces that you would fit in carbon sheet for the mounting of stingers , struts or rudders in a cat.
Those motors have the capability of delivering 6hp constant or 13hp max in total. Do you really think they will notice a couple of grams of aluminium?
Absolutely not in my experience.

I do the same for the hardware & turnfins on riggers & hydroplanes. Never an issue.

[Prodrvr]

Very good

[royalcasa]

2F538F7C-4C74-45E4-BE32-8D8A8257F099.jpgTP vs HRC cooling Jackets, HRC jacket should be more efficient in cooling the motors

[royalcasa]

412502DA-0951-4FE3-AF66-C97DC970D573.jpgAnother piece of the puzzle arrived

[royalcasa]

4C23B379-175E-47B4-8EB6-C42A8A49FFEB.jpgNew 447 props Sharpened and Balanced by Andy Brown