Rigger sponson sizes

[Simon.O.]

I am looking to do a new set of sponsons for my Krabs copy.
The existing ones are fast but I can do faster and they need to be stronger than the existing ones too. I know this

If you have a rigger, can you do a couple of measurements for me.
Overall boat length ( a photo is good)
Ride pad width
Sponson overall length.

I have the ones for a matrix and predator

Once I accumulate a few more I can sort out what I need.
At the moment I have a 55mm wide pad and I believe this is too wide.
I feel it needs to go to 30-40mm 1.25 to 1.5"

[Reesor@work]

Hi Simon,

I am at work right now so I can't measure the exact sponson length(s), but this is my T Rigger. Its 45" long, 4" tub width, runs 10S2P weights in at 15lbs RTR. The sponson bottoms at their trailing edge is 2" width. Overall sponson length is around 14".

On my P rigger, sponson bottom width at trailing edge is 1.5" with a ride pad of 1/2" width. Length on this boat is 34", sponson overall length is 11".

Steve

[mobychev]

rigger pads

Hi Simon
This is a scaled up Keps freebie, tub is 900mm the pads are 30mm wide 300mm long o/a 260mm from trailing edge of sponson to front. 105kmh yesterday,
still along way to go to get the most out of this.
probably down at Wattyl this Sun if fine.
Graham

[Simon.O.]

Hi Simon,
On my P rigger, sponson bottom width at trailing edge is 1.5" with a ride pad of 1/2" width. Length on this boat is 34", sponson overall length is 11".

Steve
This 1/2"wide pad ?? How thick is it and how far forward does it go.

Graham
Nice Kepps !! 105k ? Good stuff man, I hope to get that too, soon. That is what this new bit of research is all about.

Thanks so far guys, keep it coming.

[Meniscus]

Simon, I'll measure as soon as I get the chance and provide data NLT (No Later Than) Monday.

[Reesor@work]

Simon,

The ride pad is 1/8" thick and about 5" long...tapered to blend in with the sponson, but at leat 4" of full thickness before I taper it.

My AOA is typically 3-4 degrees depending upon the size of the hull and the water...

[Simon.O.]

Thanks for the data so far.

Steve I like the idea of a 1/8"x 1/2" ride pad, I can fit these to the existing sponsons as they have a nice flat ply bottom. I will do a set of 1/8" pads in varnished balsa (no surprise there) and see what happens.

I have the new sponsons nearly made and they will take a week of sealing, sanding and varnishing until they are ready to go on the rigger.
That is good as I will not hit the ponds again for a week as it is.

I will update the build of these new sponsons in my 4S rigger thread.

Thanks again.

[detox]

You can experiment with different ride pads. Simply attach different ride pads using light mist coat of 3M high tack spray adhesive then remove and reapply pads until you find the shape and angle you like.

A wet 2 degree AOA will be more stable if you have the power to push it.
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