Large scale gas airboat pictures
#1
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Large scale gas airboat pictures
These are a few pictures of my brother's scratch built gas airboat. The hull is all fiberglass construction and the motor mount is welded steel tubing. It has a echo trimmer engine for power. This setup still uses the clutch in the drive. I know this is a little unusual but it allows the boat to come to a standstill with the engine idling. We had to make a lot of test runs and changes to the setup of the boat to get it right but it works great now. We have spent quite a bit of time reading other people's posts here and have learned a lot. I just thought someone might like to see our project. I will try to post a short video later.
#2
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RE: Large scale gas airboat pictures
Thanks for sharing!! And a nice job on the build!!
I'm looking forward to seeing the boat in action. Is it a pure flat bottom?
Where are you in Fl? Let's get together sometime!
I'm looking forward to seeing the boat in action. Is it a pure flat bottom?
Where are you in Fl? Let's get together sometime!
#4
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RE: Large scale gas airboat pictures
Very Nice!!!! How did you secure the prop? Are you using a prop adapter? BTW it might be a good idea to get away from the wooden prop.
#5
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RE: Large scale gas airboat pictures
The boat is 48 inches long 21 inches wide. It is a pure flat bottom with two short strakes to keep it from sliding so much. We have a lathe and milling machine so we were able to machine the clutch bell to accept a custom billet aluminum prop adapter that tightens down securly against the clutch bearing. It is very strong and true.
We would like to use something other than the wood prop but have not been able to find a pusher this size made out of something better. We tried many other prop sizes and the boat works best with the 18x6 that we have on it. The boat is kind of heavy so it seems if you go smaller with the propellor the prop will not grab enough air to get the boat up on a plane and if you go much larger with the prop it is too much for the engine to get it's RPM's up into it's power band.
We did have problems at first with water spray hitting the prop at times but if you notice in the picture the boat has spray rails on the sides. Now when you run the boat the propellor never comes in contact with any water. As I said the boat took a bit of testing to get right.
I have been running regular gas and nitro racing boats for a while and was quite surprised a what a challenge it was to for us to get this airboat working correctly. The info we found reading the posts here were al ot of help.
I will try to get the video posted soon.
We would like to use something other than the wood prop but have not been able to find a pusher this size made out of something better. We tried many other prop sizes and the boat works best with the 18x6 that we have on it. The boat is kind of heavy so it seems if you go smaller with the propellor the prop will not grab enough air to get the boat up on a plane and if you go much larger with the prop it is too much for the engine to get it's RPM's up into it's power band.
We did have problems at first with water spray hitting the prop at times but if you notice in the picture the boat has spray rails on the sides. Now when you run the boat the propellor never comes in contact with any water. As I said the boat took a bit of testing to get right.
I have been running regular gas and nitro racing boats for a while and was quite surprised a what a challenge it was to for us to get this airboat working correctly. The info we found reading the posts here were al ot of help.
I will try to get the video posted soon.
#6
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RE: Large scale gas airboat pictures
If you are looking for more bite with a smaller prop, try a 3 or 4 blade. It may take something off the top end, but you should get better thrust for the heavier boat. How much does it weigh?
#7
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RE: Large scale gas airboat pictures
Dogmoat is right you could go to a three blade... drop the dia. and increase the pitch and you would get about the same amount of thrust. Master Airscrew has a three blade 16x10 pusher for $19.95 at http://www.masterairscrew.com/GoCart...66&RootID=1054 . I don't know if the thrust will be excactly the same but it should be close.
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Last edited by jimcathy6474; 09-21-2015 at 07:01 AM. Reason: no video
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Last edited by rcollector; 09-22-2015 at 06:37 PM.
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#14
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I disable the comments because I have seen a lot of rude , tasteless, irrelevant comments posted on other people's videos. I would rather discuss or have people comment here at rc universe . Thanks for your compliment on my videos!