Here's a really stupid question!

[smittythewelder]

Wonder if any other old guy recalls seeing anything like this.

Back in my era (Pleistocene), well maybe 1962 or thereabouts, and growing up watching the Unlimiteds throwing their monster roostertails at the races on Lake Washington, I saw something outrageously hokey on a family trip east. Crossing a lake in the Midwest was a big heavy slow pleasure boat, something like a 20' Thompson, droning along at maybe 28-30mph . . . and throwing a high arcing roostertail!! I should say, "roostertail of sorts"; it looked more like the tight solid stream of water you'd get out of a garden hose with no nozzle and a lot of pressure behind it. I recall my uncle, who had a little marina on that lake, saying that some little boating hardware company had invented an attachment you could screw on the bottom of your transom with the sole purpose of scooping up water and throwing it up in the air behind your boat to simulate a roostertail and make your tub look FAST!!



(FWIW, as props got more efficient, the newer Unlimiteds threw roostertails that, disappointingly, were lower and less impressive than they were in the old days.)

[filthy phill]

there is a company who actually make these today, I will try and find it for you, it looks like a little anchor type thing and gives impression of a roostertail.

[Fastjeff57]

I remember those. Some were nothing more that a hunk of tube aiming upwards on an angle that bolted to the cav plate. Impressive!

Jeff

[filthy phill]

well nowdays people are too lazy to make stuff, they go and BUY a rig to do this.
here is the site that sells the product and even shows videos of it attached and working.
and yes people are paying good money for these things ha ha

http://roosterboost.com/

[Ketzer]

Humans are funny.

[Fastjeff57]

Year end report: Made some serious progress this year (though the boat is still a slug--hull dynamics problems). Was able to build two homemade props that allowed running the prop shaft about 1 1/2 inches below the padl without slippage. Whoopee! Motor overheated instantly at that height, but the prop held. Made some runs at lower heights (where the water inlet still functioned) and gained over 5 mph from where the cav plate was just above the pad.

So, to answer my original question--Does a prop slip more just as it is raised, then bite when its raised somewhere? No. If that sucker won't grab when it's raise a little, it'll slip even worse as it's raised some more.

Next year I'll be running my water inlet via a hose and fitting mounted on the boat, so she'll stay nice and cool. Got that idea here (see photo) from a really smart fellow (whom I don't know, but thanks!)

Jeff

[hupiveneilija]

It defenetly slips more and more when you go up. Idea go higher is to get gearcase drag lower,
but that you know, by using more pitch on prop to take care of that higher slip and gain speed.

If need to correct, please do so.

-J-