Twin Cat Strut assembly on a budget -> help please ;)

[norbique]

It's not hard to understand. I got it. But a pic is always welcome.
I will have to cut open the transom bottom to make the box, but I'll do it if I have to.

[norbique]

How long should the struts be? From sponson to prop edge?
Boat length from tip to back of sponson is 102cm ~ 40"

[Simon.O.]

Norbert, if you are looking for the set back from the rear planing surface then I can help.
10% of wet length is a minimum and up to 15% is a good area to play in. I have one cat that is now at 15% and the new bigger cat will begin there and go aft from that.
I have it on good authority that these are solid numbers and I have water time too to show my results.
Go for 10-15% aft and allow for adjustment if possible.
Those who make thier own hardware can send a strut anywhere.

I am watching your fine work.

[norbique]

OK, Thanks Simon!

So in my case that would translate into 102mm at least? That's a 90mm strut plus teflon trust bearings and the drive dog right?!

I don't know where, can't find it, Shockerman said I should not let the props too far out the sponsons... Can you (Shockerman) confirm this? After all it's your hull design.

Since I can't get SS tubes, I'll have to stick to what I have. Brass tube, D: 8.5mm d: 7mm. Wonder if it will be strong enough with this wall thickness? It won't be as nice and shiny as a SS would be, thus I'm gonna paint it black or somethin'

I just need to find some good bronze to make the bushings from....

[shockerman80]

out meaning left to right not forward to backward. It makes it really unstable when the are farther out. think left to right teeeter toooter one prop is in the water the other isnt what happens?

[norbique]

OK got it. So struts as close to tunnel as possible?!

[G Doggett]

Yes, like this as close to the tunnel as possible.
Graham.

[norbique]

Thanks for the pictures Graham! I don't think I can get as close to the tunnel edge like you did, since the construction doesn't allow it. I'll put them as close as possible.