Stinger placement on a cat

[ozzie-crawl]

Just after some thoughts. I just bolted up some stingers on a new cat hull.
I shaped the top of the bracket to get them higher up,but it still leaves the bottom of the stinger flush with sponson bottom.
If sitting the hull on the table the stingers sit about 2mm of the table due to angle of sponsons.
stinger is fairly thick so center of shaft would be 7mm from bottom of sponson.
Will this be ok or cause issues being flush ???

Not sure if this helps but a pic of setup.

[Remmie81]

Looking at the picture it the water leaving the sponsons will hit the stinger and causing drag.
Do you have them mountend in the middle of the sponson or as fas as possible to the innerside?
(maybe you can post a picture from the back?)

[ozzie-crawl]

I have them as close in as possible but there around 3mm past center. will get a better pic tomorrow when its day light.
I was thinking i mite make a piece to fill the gap between sponson and stinger.

[ozzie-crawl]

Tried getting a pic. not the best using the flash.

[Remmie81]

Looking at your last picture here is what I should do:
Grind away the right bottom bolt hole were the bolt goes into (3 bots should be more then enough to hold it in place)
Then you can move your drive further inwards and your drive should then be flat or just above the sponson.

[ozzie-crawl]

I actually thought of that before i drilled. just been going threw some older builds on ose. found a twin cat that has the same stingers mounted near flush to bottom of sponsons.
Fairly much identical to mine.
it ran in the 70 mph range. So not sure now if it will matter

Looking at my first pic the angle makes it look like the stinger is below the sponson were its not

[Remmie81]

Then you could fill the gap up like you suggested.
It could be that with the drives that low you are "extending" the sponson.
That could mean that the boat will try to run on it eg not flip over that fast or the boat will run very wet.
But I would not know what it will do

Do you by the way have a picture of the complete boat? Im curious

[ozzie-crawl]

After looking at the rear of boat for half an hour i realised the stingers were not square with the rear of sponsons
I squared the stingers before mounting but then re adjusted after running a ruler across all the steps.
After re adjustment the front of the stinger is now about 1mm above the sponson bottom and a bit closer.
looks identical to the sprint cat pic i found (close up is the sprint cat)
other pic is my cat

[srislash]

Is that your Fantasm Ozzie.How long are those stingers? My Shocker stingers are up 10mm @ center but they are 110mm long.I don't know if we're going to fast for the various lengths to matter I've been giving this some thought as of late for the next build.

[ozzie-crawl]

Hi mate. its a cheetah hull.
Same stingers as Keith used on his cheetah. think he got his stingers a mm or so further up than mine.
I could have got them a little bit higher but found if i put them square to bottom of sponson extension then the stingers were not dead vertical. thought vertical and flush was better than up another mm and not vertical.
I am only shooting for around 50-55 mph max. not trying to set any speed records.
my stingers are positioned same as Keith's as far as not being center of ride pad and his turns like its on rails.
Hope he does not mind but here is his first run in a small test pond http://youtu.be/GLQ2iAtrqCo

[Remmie81]

ok if the stinger is now 1mm above like you said it should be fine!

Hull looks nice man!

[srislash]

You may find the need to fill the gap between hull and stinger with silicone.That I know is a source of water coming inside on mono's.

[ozzie-crawl]

ok if the stinger is now 1mm above like you said it should be fine!

Hull looks nice man!

Thanks Remmie. will paint it once all hardware/motor mounts etc are finished. I Love the inside look carbon kevlar

[ozzie-crawl]

You may find the need to fill the gap between hull and stinger with silicone.That I know is a source of water coming inside on mono's.

The front of the stinger has a very big opening for about a inch before it narrows down to the bushings. i guess this is to allow adjustment.
what i will do is running the stuffing tube about 3/4 of the way in see how it goes.
Never built a twin but thinking back to every other cat i have had they tend to run with a slight nose up attitude. this makes me wonder if the stingers will even be parallel with the water.