The Unofficial 7.5cc Tunnel Thread
#151
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RE: The Unofficial 7.5cc Tunnel Thread
We are running 50% nitro k&b we test the speed http://www.youtube.com/watch?v=6wgHB...re=relatedwith radar gun 80 km/h
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RE: The Unofficial 7.5cc Tunnel Thread
Awesome nitro boater!!! you will have to upload some close up pics of of your boat, looks like a mean machine!!! Nice one!!!
#153
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RE: The Unofficial 7.5cc Tunnel Thread
Thanx bud,its a seebold hull wth a 8 year old k&b.Will upload some pics and my son is going to race this boat in the South Africa Nationals
#154
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RE: The Unofficial 7.5cc Tunnel Thread
sup guys have a lap cat 2 with the original k&b 7.5. hopfully ill be able to get it running this week.(if i can tune it) and it need new paint, what grit would u suggest? and what type of paint>?
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RE: The Unofficial 7.5cc Tunnel Thread
Hi there guys!
How did you go with your boat Bigstang? I am working on getting another tunnel back on the water. Just finished building a new radio box and given it a bit of a tidy up and will run a mild mod K&B on it and a Hitec 5745 for the steering. Weather is pretty poor so got some time to get a new prop sorted- I use the X447.
If anyone has any piston and sleeves they would part with, could they PM me please. I will use a used one as well as long as it has some life left in it!! Cheers!
I will upload some pics soon as I get this glue of my hands!! Busy building a woodgas tunnel as well!!
Hope the NATS were good to you Nitro boater!!
All the best,
Dion.
How did you go with your boat Bigstang? I am working on getting another tunnel back on the water. Just finished building a new radio box and given it a bit of a tidy up and will run a mild mod K&B on it and a Hitec 5745 for the steering. Weather is pretty poor so got some time to get a new prop sorted- I use the X447.
If anyone has any piston and sleeves they would part with, could they PM me please. I will use a used one as well as long as it has some life left in it!! Cheers!
I will upload some pics soon as I get this glue of my hands!! Busy building a woodgas tunnel as well!!
Hope the NATS were good to you Nitro boater!!
All the best,
Dion.
#156
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RE: The Unofficial 7.5cc Tunnel Thread
WELL. need to get a charger for my 12v 7ah batter lol, walmart has a charger that will charge at 1.5amps for a 12v small battery so im gonna get that but i put the tune back to stock but didnt start due to low juice in battery, and made a new pull-pull cable adapter for the trottle, the last one broke/rataining clip came off, but with some spart parts from a nitro truck i made one work. its pritty much the same thing just a tad bigger and using and eclip,
maybe today ill hit walmart and get the charger.
and now i gotta real reseal the 3inch piece of wood in the front of the battery box. but hopfull i can find a big pond to go hit
F1TUNNEL, were did u get your new radio box at.
maybe today ill hit walmart and get the charger.
and now i gotta real reseal the 3inch piece of wood in the front of the battery box. but hopfull i can find a big pond to go hit
F1TUNNEL, were did u get your new radio box at.
#157
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RE: The Unofficial 7.5cc Tunnel Thread
I make mine from 2&3mm birch ply from the hobby shop with perspex/acrylic sheet for the lid. I seal the wood both sides with west system epoxy. Prather also make radio boxes(fibreglass tub style) for tunnels, I have seen them on ebay plenty, they may be listed under Lapcat parts. There would be others but I just make mine. You can use ca glue on the joins with an accelerator to speed up the job and go over the joins with epoxy where you want. You can use balsa wood to make your box to reduce the weight if you are racing but these boxes wont be as durable as ply or f/glass. I will take some pics for you. I recently found a nice waterproof switch in England, have used dubro and other set ups but will get a pic of this new(for me) one I got-aluminium with nice double o-ring seal.
All the best,
Dion.
All the best,
Dion.
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RE: The Unofficial 7.5cc Tunnel Thread
more!! the orange hull has an 11cc on it for now, good for 7.5 as well. The switch I found on ebay.
All thye best,
Dion.
All thye best,
Dion.
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RE: The Unofficial 7.5cc Tunnel Thread
nice-nice!!!! for my radio box im gonna use servo tape this time last time i just used shoo goo lol and thats how i riped out my front piece of birtch,
but heres my lapcat 2
but heres my lapcat 2
#164
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RE: The Unofficial 7.5cc Tunnel Thread
Hey,bigstang.. I'm looking for a lapcat...check it out.. http://www.rcuniverse.com/market/ite...temID=751700If anyone has oneor knows someonewho does....hook a brother up! Thanks Kelly 954-818-8576
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RE: The Unofficial 7.5cc Tunnel Thread
Any luck with the Lapcat Bigstang? They do come up on ebay a fair bit- new and used!! I would like to get one of those HTB tunnels one day. I have also seen an extremely nice local built wood tunnel recently, I forgot the name of the builder so I am trying to get that again. I should have taken a photo- the owner is a member here so maybe I can get him to upload one. He had a cmb 13cc to go on it with a hyperformance lower and carbon pipe-made you drool!!!
All the best,
Dion.
All the best,
Dion.
#166
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RE: The Unofficial 7.5cc Tunnel Thread
Just put a tunnel boat togeather for the summer It is a 11cc K&B on a Aerotech hull. I have been runing it on 33% nitro and I am getting around 65 to 70ish mph.
Bill
Bill
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RE: The Unofficial 7.5cc Tunnel Thread
Hi Bill,
Nice boat you have there!! I look forward to getting mine on the water. What prop are you running on your 11cc?
All the best,
Dion.
Nice boat you have there!! I look forward to getting mine on the water. What prop are you running on your 11cc?
All the best,
Dion.
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RE: The Unofficial 7.5cc Tunnel Thread
Dion I have never look'd for the size. Where would I look for it? I got this motor used off this site and that is the prop that came with it. As many times that I had the prop off you would think I would have look'd
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RE: The Unofficial 7.5cc Tunnel Thread
it should be on the center were the shaft goes into. and the very middle of the ring
like this, its an ebay link but.... it shows what im talking about
http://cgi.ebay.com/Octura-X450-Bery...#ht_1852wt_901
like this, its an ebay link but.... it shows what im talking about
http://cgi.ebay.com/Octura-X450-Bery...#ht_1852wt_901
#170
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RE: The Unofficial 7.5cc Tunnel Thread
65-70mph? That's record breaking speeds for an 11cc Tunnel. Did you happen to mean km/h? Looks really good man! Get us a video if you can.
Ryan
Ryan
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RE: The Unofficial 7.5cc Tunnel Thread
Mph. I could be wrong I am just guessing. The po po hang out where I run the boat. I am just waiting for one to pull up and get some radar on it. Then I will know what it can do. What is a good prop to run? when I get home tonight I will look and see what is on the boat now.
Thanks Bill
Thanks Bill
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RE: The Unofficial 7.5cc Tunnel Thread
That prop may be one of the best for the hull but no one will be able to tell you for sure. Testing, Testing, Testing is usually required.
Here's a chart available that may help:
[link=http://radiocontrolinfo.com/NitroBoat/propeller.html]Nitro Prop Selection[/link]
There's still a LOT of fine tuning to this section needed. Just a matter of time.
You will probably be best with the larger range of props if your engine is stock. A modified engine with a tuned pipe will require smaller props due to increase in RPM.
Ryan
Here's a chart available that may help:
[link=http://radiocontrolinfo.com/NitroBoat/propeller.html]Nitro Prop Selection[/link]
There's still a LOT of fine tuning to this section needed. Just a matter of time.
You will probably be best with the larger range of props if your engine is stock. A modified engine with a tuned pipe will require smaller props due to increase in RPM.
Ryan
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RE: The Unofficial 7.5cc Tunnel Thread
hey guys new to the site and back into nitro tunnels. have an original hotshot sprint kit# 1323 7.5k&b stock. bought and built it 20 yrs. ago when i was ten with no clue. the hull has a slight twist in it. took the engine apart @ that age and put the wristpin in wrong and teflon pad got lost thru exhaust port. seized the piston in the sleeve. and was put on shelf as was. i recently got back involved with nitro airplanes and gained bunch of nitro engine info. needless to say i lost the piston in my travels, but found one from g&m models. had to clean the gummed up engine with little alcohol and reassembled it. the thing fired right up. the engine runs excellent but with the imperfections of the hull the kit runs good, hard to tune. anyone know about the newer hotshot sprint 7.5 kit#1328? will put picts up in abit. the cowl and nose are a little on the blockish side because of lack of buildind skills. but how much this thing is providing now.