CAT sponson shape and angle questions

[FastVee]

Just received my hotr 32" cat and the sponsons are in a weird angle. -the tunnel is also U shaped -is this normal?

So I wanted to know will this srew up the handling and is there anything that can be done to remedy this?

the pics make it look better then it really is...

One would think that the angled sponsons would act like turn fins? (graps too much and flips the boat when cornering?)




Pate

[NativePaul]

Hmm, anhedral on the sponsons isn't how I would have done it, but then I've never tried it, all my cats have had dihedral of varying amounts but it looks to be the same amount on both sides and at all steps down each side so it could be a design decision,I've seen a few H&M cats although not the Agitator and they all had a small amount of dihedral, hearing that the HoR cat is a H&M Agitator splash I would guess that it us due to either the polyester hull being taken out of the mold too soon and flexing, or the splash mold being taken off the H&M boat too soon and warping giving all the subsequent boats the warp, are they all like this?

The normal method for blueprinting bottoms is wet sanding with a large firm sanding block, but it looks like taking that amount off would be likely to go right through the hull or at least severely weaken it, I would cover the bottoms with balsa sheet, block sand the balsa flat or with slight dihedral then stick a sheet of 1/32nd ply on top, sand it flush with the sides and seal the wood with epoxy.

[FastVee]

The agitator


sponsons straight.


My copy has a bit more warp/anhedral on the right sponson then the left one.

What I have seen the other hulls have only slight or none warping.

The deck has some warping too, but that is not problem to me, just want this to drive nice!




Pate

[G Doggett]

Sorry mate, NativePaul is right, your hull is distorted either from being squashed in the mail or from polyester shrinkage , or a bit of both.
It will handle like dog like that.
The sponsons should be flat or have a few degrees of dihedral ( inner edges touching the table and outer edges off the table).
I have just bought a Korean cat hull that has the same problem.
I am going to spread the sponsons apart again by wedging a piece of wood between them to push them back to the correct position, and them figure out some way of bracing or reinforcing the hull inside to make it stay that way.
I'll post my fix once I have figured it out.
Graham.

[FastVee]

Yeah, if you figure it out, please do inform me how you did it.

I guess I´ll try heat next. Using something to push the sponsons and aplying heat until the f/g softens and it should bend then.

I did this to a crappy Kyosho twinstorm a while back (the lid would not sit right, heated and bend it and it fits now)

I should have got the h&m hull instead...

[line6]

you could just add a few layers of glass and the sand it down to the way you want it. ya kinda of a pain especially on a new hull but it is a knock off. Also you could try and contact the seller and tell them your unhappy and ask what they can do for you. or mail it 2 me

good luck

[FastVee]

I emailed the seller 24 hours ago, no response yet.

If I would fix the sponson shape with f/g or filler/gelcoat, would that be enough?

-will that anhedraling and the u-shaped tunnel screw things up in any way?



Pate

[G Doggett]

The side walls of the tunnel should be vertical, not leaning inwards, and parallel.
Some are even angled outwards but I suspect this is to make them easier to pop out of the mold.
Rather than bogging and sanding, try to force the sponsons apart to get back to the correct designed shape and then wedge it with a peice of wood cut to the correct width, and then figure out a way to make it stay there.
As I said, I will let you know how I correct this distortion on my hull.
It's a PITA but any variation from the H &M designers set up is bound to affect performance, and I guess is the difference between an original and a splash.
Graham.

[FastVee]

Well, the seller replied... "It is designed like this"

And yeah, you sometimes get what you paid ... Oh, well, I guess that means I have to fix it ...


Maybe the forcing with a block of wood and then laminating some c/f inside will fix it a bit, and then make final adjustments with filler.

The pic from hotr does look like they should have some bend...-but that can be just the camera´s barrel distortion .


Pate

[FastVee]

I forced a wooden block between the sponsons and layed 1 layer of c/f, and another layer on sponsons. -if I´ll block sand them straight there is something to sand...wont sand trough the hull

Will see tomorrow did this straighten it any(think NOT).


Pate

[ksm2001]

Good Thread Pate, this has me really thinking now too since I have the same problem I didn't C/F mine yet.

Ken

[FastVee]

Ken, the seller told me that this is designed this way...(no, I did not belive him eighter), oh well it´s 100 buxx, what can one get for that price...

The carbon is dried, no change in hull shape. -atleast it looks good on the inside now...

Will test drive it next weekend

[line6]

Ya, at this point i would just run it and go from there.

good luck

[Punisher 67]

Interesting thread guys , very interested to see how the fixes pan out......

[Jeff Wohlt]

Mine has a little on one side and not the other. They can easily be filled if you want.