homemade jet bathtub that was powered by a BBQ propane tank

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55dcyinely
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Re: homemade jet bathtub that was powered by a BBQ propane tank

Post by 55dcyinely » Thu Apr 07, 2011 4:14 pm

Second Generation, Master Blaster 2. The second annual Ely Nevada Cave Lake Bathtub Race on Saturday June 25th 2011. Only 84 days left.
This is a preview of my entry for this year’s race. A twin Lockwood pulse jet engine. The prototype worked so I built the full scale
Lockwood pulse jet, two 4" intake and two 5-1/2" exhaust ports. Haven't tested it. But it should be loud enough. The propane tanks on last year’s model scared the
local Sheriff’s department and the fish and game officers to death! The Capitan of the Sheriff's department was quoted as saying "it is an accident waiting to happen there are going to engine parts spread over the entire lake!" So I'm running high octane gasoline. Which means extra weight of a battery and a fuel pump.
I hope to have some competition this year!
MasterBlaster2.JPG
Mike, have you started on that PUTT-PUTT?
Viv, Jutte, what's your entries going to be?
See ya'll there.
Oh and Metiz, is this one big enough?
Last edited by 55dcyinely on Thu Apr 07, 2011 5:14 pm, edited 1 time in total.

Viv
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Re: homemade jet bathtub that was powered by a BBQ propane tank

Post by Viv » Thu Apr 07, 2011 4:27 pm

Hi Doug

That's a monster your building there ;-) what did the prototype run like? any pics, are your clamps holding the exhaust pipes able to slide due to heat expansion?

Oh and ordinary pump gas will be fine no need or high octane any thing on a pulse jet

Viv
"Sometimes the lies you tell are less frightening than the loneliness you might feel if you stopped telling them" Brock Clarke

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55dcyinely
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Re: homemade jet bathtub that was powered by a BBQ propane tank

Post by 55dcyinely » Thu Apr 07, 2011 5:07 pm

Hi Viv,
I didn't take any pitchers of the prototype. It ran good but when I gave it full throttle it acted like a flooded auto engine. The fellow that helped build the prototype bought it from me.
And even used it to thaw out one of the Copper minings earth movers this last winter. He said it used about 14 gallons of propane.
Yes, the engine mounts will allow for movement. I really don't expect it to move any faster than last years model.
Basically pulsejets are not much good with displacement hulls but if you could get a decent hull up on the plane they'd be great. by Bruce Simpson
And I think I'll hand out free hearing protection too.

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Re: homemade jet bathtub that was powered by a BBQ propane tank

Post by Jutte » Thu Apr 07, 2011 8:29 pm

Whoa ...yeah...they'll be hard out trying to find all those
engine parts from a valveless engine.... :lol:

55dcyinely
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Re: homemade jet bathtub that was powered by a BBQ propane tank

Post by 55dcyinely » Fri Apr 08, 2011 4:19 am

Hey Jutte,
I tried to explain what a Pulse Jet Engine is. But, the Sheriff is the LAW and if he says it dangerous! well thats the end of discussion.
Most of the people really thought it was cool. Even if it only went 4 knots an hour. After all that the event planning committee
invited me back this year. Should be some real fun, Bathtubs and Beer! Of course the Fish and Game won't let anyone participate
if you've been drinking before the race.

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Re: homemade jet bathtub that was powered by a BBQ propane tank

Post by 55dcyinely » Fri Apr 08, 2011 4:33 am

Viv,
I was really just pulling your leg when I said:
even used it to thaw out one of the Copper minings earth movers this last winter. He said it used about 14 gallons of propane
We were talking about your YouTube video (PHS burner fitted with acoustic decoupler) but never pursued that avenue.
Thanks again

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Re: homemade jet bathtub that was powered by a BBQ propane tank

Post by 55dcyinely » Sat Apr 09, 2011 4:03 pm

Viv wrote:Hi Doug

That's a monster your building there ;-) what did the prototype run like? any pics, are your clamps holding the exhaust pipes able to slide due to heat expansion?

Oh and ordinary pump gas will be fine no need or high octane any thing on a pulse jet

Viv
I read somewhere high octane gasoline made a real difference.
I forgot to mention where my inspiration for this project came from.
file_61_2849.jpg
file_61_2849.jpg (20.75 KiB) Viewed 4639 times
Mike Build Log
viewtopic.php?f=3&t=4595&st=0&sk=t&sd=a&start=195
As the project gets closer to completion I'll post more up dates. Maybe.

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Re: homemade jet bathtub that was powered by a BBQ propane tank

Post by Mike Everman » Sat Apr 09, 2011 4:42 pm

Wow, Doug, that's an amazing piece of work!
I'd love to build up the putt-putt-for-my-butt, but life is a bit hectic. I'm seriously considering coming out for that in any case. I've got it on the calendar, and another time a month before to say "it's in a month, dummy, shit or get off the pot!"
Mike
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Re: homemade jet bathtub that was powered by a BBQ propane tank

Post by Viv » Sat Apr 09, 2011 6:30 pm

Hi Doug

I think I would still go with plain old pump gas if I could, do you recall were you came across the high octane making a difference and the circumstances it was run under? we do know that ethanol mix's tend to mess with pump seals and probably alters the performance, downwards or upwards? no idea ;-)

Viv
"Sometimes the lies you tell are less frightening than the loneliness you might feel if you stopped telling them" Brock Clarke

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55dcyinely
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Re: homemade jet bathtub that was powered by a BBQ propane tank

Post by 55dcyinely » Sat Apr 09, 2011 11:08 pm

Viv wrote:Hi Doug

I think I would still go with plain old pump gas if I could, do you recall were you came across the high octane making a difference and the circumstances it was run under? we do know that ethanol mix's tend to mess with pump seals and probably alters the performance, downwards or upwards? no idea ;-)

Viv
Viv,
I've looked for the article saying high octane gasoline was better. Maybe better for a (pulse detonation engines) RE: VS talks about high octane fuel. Comment: by PyroJoe
And now that I look back even the beck tech said methanol is a better fuel than gasoline. I have a bunch of methanol 97% would that be better?
Maybe that is why the prototype acted like it was flooding out? I've always used propane, but the State of Nevada, Fish and Game want emergence cut off switches
on all motorized boats this year. I did buy a MSD electrical fuel pump, seemed to work fine.

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Re: homemade jet bathtub that was powered by a BBQ propane tank

Post by Viv » Sun Apr 10, 2011 12:57 am

Hi Doug

I have played with the other fuels but its another story I wont share here for obvious reasons ;-) I am surprised in way they want liquid fuels for safety reasons as at least gas wont form an oil slick ;-) oh well... just make sure all the lines are good and tight and cant spring a leak under pressure, that would not be fun with you in the tub with it, I assume you will have a fire extinguisher on the boat with you?

Just for clarity did the prototype flood on propane or petrol?

Viv
"Sometimes the lies you tell are less frightening than the loneliness you might feel if you stopped telling them" Brock Clarke

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Re: homemade jet bathtub that was powered by a BBQ propane tank

Post by 55dcyinely » Sun Apr 10, 2011 2:48 am

Hello Mike,
I was talking to an Ed Dempsey, out in your neck of the woods. I needed some help on an old military 3 phase 4 wire 400 HZ aircraft motor.
At first I had no idea who he was, and later embarrassed. He holds the worlds fastest electric car record. At the Bonneville salt flats! 110 miles
from my home. Here's one of his web sites; http://www.dwra.net/founder.htm
Seems he knows of work. He's really smart and all round nice guy.

Viv,
It was gasoline, that seemed to make act like weird.

Thanks Fellows

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Re: homemade jet bathtub that was powered by a BBQ propane tank

Post by tufty » Sun Apr 10, 2011 8:14 am

Given that you'll be running on water, it seems to me that water injection might well give you a handy boost.

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Re: homemade jet bathtub that was powered by a BBQ propane tank

Post by 55dcyinely » Sun Apr 10, 2011 2:07 pm

tufty wrote:Given that you'll be running on water, it seems to me that water injection might well give you a handy boost.
Hi tufty,
Funny you mention that but I’ve already set up another pump from a RV camper specifically for pumping water.
Personally, I don’t see any advantage in trying to run on water. But you, mentioning water injection most defiantly over the plastic fiber pontoons will keep them from melting.

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Re: homemade jet bathtub that was powered by a BBQ propane tank

Post by tufty » Sun Apr 10, 2011 6:43 pm

Put succinctly, water injection = extra massflow = extra thrust.

Eric Beck is the man for chapter and verse on it. Here's some good stuff Mark found - viewtopic.php?f=2&t=4628&st=0&sk=t&sd=a ... ion#p54152

Oh, and augmentors.

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