Thread Tools
Feb 20, 2015, 08:36 PM
Registered User
cayenne's Avatar
Thread OP
Build Log

Handmade 25cc WeedEater Mono Boat. Video Build Blog


Hello RC friends!
That's my first post here and hope I choose right thread to post a building blog.

Past year I've build Gas engine powered boat from plywood, using my own plans. Engine - is weedeater 25cc. Length ~1.3 meters. Weight ~10kg.

As the project started in May and I had not much time to build it perfect before summer season - it was a quick project, just to see - what I can do with this motor and will it sail good?

As a result - I was impressed and did not expect such a nice boat with good speed and sailing stability. Burned 4 liters of gas (that's about 6-7 hours on a water) and did not sink it or got some water inside.

However I was not happy with a boat painting and wanted to remake few parts in power unit.

This winter I've removed all paint from hull, uninstalled engine and all other stuff and started big rebuild process.. It's still in progress, but i've already got few things done.

So i'm going to post here some pictures and videos shoot past year, and then a rebuild process.

If you want to help me with this and next projects you can go there http://sparklylights.com/rchandmade/donate.html and send few bucks for new RC goods and/or models repair and bulding. Thank you !

Hope you'll enjoy and get some fun
Last edited by cayenne; Jun 23, 2015 at 05:20 PM.
Sign up now
to remove ads between posts
Feb 20, 2015, 08:50 PM
Registered User
cayenne's Avatar
Thread OP
Past years videos

#1. Installed prop and testing it with a drill

RC Handmade - Boat rudder, strut, prop and trim tabs installed (1 min 0 sec)


#2. Mounted gas engine. First motor run inside hull.

RC Handmade - first start of WeedEater 25cc engine mounted into hull (3 min 39 sec)


#3. Motor connected with shaft and prop

RC Handmade - WeedEater engine installed and connected with prop (1 min 21 sec)


#4. Installed Radio

RC Handmade - Throttle for 25cc WeedEater gas boat (1 min 9 sec)
Feb 20, 2015, 08:56 PM
Registered User
cayenne's Avatar
Thread OP
And few videos from on-the-water testing and sailing

#1. First water testing. Was very scary to sink it, very careful runs. Boat is not even painted yet

RC Handmade - First run of 26cc WeedEater gas boat (2 min 55 sec)


#2. Second water testing. Checking max speed and learning to do some maneuvers.

RC Handmade - 25cc weedeater boat (4 min 14 sec)


#3. Nice close up runs and a lot of splashes ))

Rc Handmade - Summer water fun (2 min 9 sec)


#4. Check that crazy U turns I've learned to do. It's possible only when doing right turn, I think because of rudder - it's mounted right to the prop, so right turns is much easier to do

RC Handmade - Crazy turns on my 25cc Gas Boat (0 min 58 sec)
Feb 20, 2015, 09:01 PM
Registered User
cayenne's Avatar
Thread OP
And now current progress on the project:

First - i've ordered new motor for it. It's another Homelite 25cc engine, similar to what was already installed there. Difference this new motor has a clutch so boat will have now iddle. Also this motor has better positioned mounting holes, so I could do very nice and solid motor mount.

#1. New Homelite motor testing and clutch work demonstration

RC Handmade - Homelite Motorhead Clutch test run (2 min 17 sec)
Feb 20, 2015, 09:06 PM
Registered User
cayenne's Avatar
Thread OP
Another small update to hull - spray rails.
If you saw first hull version on the photos above you can notice there are two splash rails each side. And as I noticed those did not work properly on the water.
Top splash rail was too far from water line, bottom rail - was always underwater...

This time I decided to make only one rail each side and put it between position of old rails. Hope that will do the trick )

To make spray rails i'm using plastic wall protect corners 10mm width.
Sanding one side on grinder and glue with a Kleiberit Pur. Looks and works very good!

See how it was done:

RC Handmade - Easy Spray Rails for Boat (5 min 3 sec)
Feb 20, 2015, 09:09 PM
Registered User
cayenne's Avatar
Thread OP
I'm open for your questions and advices. Work still in progress.
Current step - final hull polish before painting and motor mount.

Watchout for new videos soon.
Subscribe my channel.
Post your comments here.
Share your ideas.

And thank you!
Feb 21, 2015, 09:10 AM
Registered User
632bigduke's Avatar
Gizmoengines
To buy a real Rc boat engine. Get the fully mod 30.5 and a good prop from them as well
Your wood boat building g skills are pretty good and I like to see scratch builds .
Was it a Zipp kits boat ?
Feb 21, 2015, 10:36 AM
Suspended Account
Homelite motors are a good choice for a boat but the newer ones (what you have) is junk. You need a 30cc . You can tell by your video that the engine is restricted. Remove the restrictor caps and on the carb lean it out. You can change the carb out to get more speed and power. The older Homelites are a better motor. Too get rid of the right spin outs get a speed turn fin and mount in on the back right side of the boat to stop the spin outs.
Last edited by txt killer; Feb 21, 2015 at 10:47 AM.
Feb 21, 2015, 10:37 AM
Registered User
Nice project :-)

The "fast" right hand turns are known as hooking, this is something we try to avoid... The still picture on the video before pressing play shows you what is going on. Right rudder is lifting the back of the boat, forcing the bow down and there you go a "hook"....

Ways to get rid of it? Reduce the right rudder throw (the boat wants to turn right anyway because of the propeller rotation), check the balance of the boat and balance it closer to the back (around 28% of boat length is a good start) and/or changing the propeller to one with less lift (all propellers will lift the back of the boat, the shape and size of the blades deciding how much).
Feb 21, 2015, 10:58 AM
Registered User
cayenne's Avatar
Thread OP
Quote:
Originally Posted by 632bigduke
Gizmoengines
To buy a real Rc boat engine. Get the fully mod 30.5 and a good prop from them as well
Your wood boat building g skills are pretty good and I like to see scratch builds .
Was it a Zipp kits boat ?

That could be my next step in boats modelling. But I dont like to buy things which I can try to do myself. I'm thinking on adding water cooling and muffer.
But as I limited in time and money - doing step by step.

No, it's not a zip kit, I bought all parts on ebay different sellers. Hull design and build- is completely my work.
Feb 21, 2015, 11:00 AM
Registered User
cayenne's Avatar
Thread OP
Quote:
Originally Posted by txt killer
Homelite motors are a good choice for a boat but the newer ones (what you have) is junk. You need a 30cc . You can tell by your video that the engine is restricted. Remove the restrictor caps and on the carb lean it out. You can change the carb out to get more speed and power. The older Homelites are a better motor. Too get rid of the right spin outs get a speed turn fin and mount in on the back right side of the boat to stop the spin outs.
Yep I see that older homelite engines, they looks much more solid built... But I won this engine on ebay for $20 only, so not a bad deal actually...

what is that restrictor ? maybe you have a link to manual how to remove it ?
Feb 21, 2015, 11:02 AM
Registered User
cayenne's Avatar
Thread OP
Quote:
Originally Posted by w3bby
Nice project :-)

The "fast" right hand turns are known as hooking, this is something we try to avoid... The still picture on the video before pressing play shows you what is going on. Right rudder is lifting the back of the boat, forcing the bow down and there you go a "hook"....

Ways to get rid of it? Reduce the right rudder throw (the boat wants to turn right anyway because of the propeller rotation), check the balance of the boat and balance it closer to the back (around 28% of boat length is a good start) and/or changing the propeller to one with less lift (all propellers will lift the back of the boat, the shape and size of the blades deciding how much).
thanks did not know it...
first build was almost 50% balanced, this time i moved motor to the back and expect to get that ~30%.
Feb 21, 2015, 11:34 AM
Suspended Account
Quote:
Originally Posted by cayenne
Yep I see that older homelite engines, they looks much more solid built... But I won this engine on ebay for $20 only, so not a bad deal actually...

what is that restrictor ? maybe you have a link to manual how to remove it ?
On the carburetor you will see a h and l setting needle On top of the needles you will see plastic caps limiting the movement of the needles REMOVE them and you can adjust the high speed more to lean out the engine and make it go faster. Did you replace the spark plug with a Resistor type? If not then you better do so.
Last edited by txt killer; Feb 21, 2015 at 11:40 AM.
Feb 21, 2015, 06:08 PM
Registered User
cayenne's Avatar
Thread OP
googled images of that caps and looks like there are no in my carburetor.
there are only H and L needles

so to get higher RPM I just need to turn H needle ?
motor must be running on full open throttle when adjusting H needle and need to try get best RPM while turning it ?


Quick Reply
Message:

Thread Tools