Dumas Big Swamp Buggy

[greenman407]

Not really a buggy but a tunnel hull powered by up to a .60 size airplane engine. True to form, I , of course, have a Fox .74 on mine and wish that I went bigger. Oh well.(Heavy Sigh!) The hull comes unassembled and is made of die cut birch and mahogany plywood. So you will be doing a lot of CAing and epoxying. It really is a lot of fun. This is my second one. My first one I equiped it with a K&B .61 and the first time out it literally flew. After that I put some weight in it to keep it on the water. It would be a lot more tame if you installed a .40 size motor, but then you couldnt do any of the fun stuff! Fun stuff like driving it up on the bank and seeking out wet standing pools of water in grass fields after a heavy rain. I would drive like mad on the water and then head for shore and up on the bank I would go , blasting around thru the grass and then back down into the water it would go , water splashing up into the blades and splattering water all over everywhere and anybody around. A 12 oz. tank of fuel seems to last forever. I sought to improve performance by filling in the bottom tunnel and making it a flat bottom. Spinning out and around was really fun and driving thru wet grass a blast. Then I built my second one. The changes I made was upgunning the engine size and installing a removable water rudder to work together with the air rudders to give improved turning capability on the water. But with the water rudder on you cant drive up on the bank and weeds catch on the rudder. With it off you can really fly thru lily pads and weeds and anything else thats there. I used to chase alligaters with it. As I charged them they would hold their ground for a minute until it got too close to them and then with a splashing crash of the tail they would crash dive as I drove thru the spot that they used to occupy. Fortunately this game of chicken ended well for the Big Swamp Buggy and her foolish driver. What, who me??? Its all hollow inside so I filled up all the voids inside with foam and its certainly never going to sink. I highly recommend it, the boat that is.

[greenman407]

Ok here are a few more taken at Devils Den at a sub fun run. Now that three bladed prop is not something that you want to tangle with , especially when its turning!!! Its a great little craft. The reliability of the aircraft type engine allows you to be able to just putt putt around if you wish and intemidate the submarines, if they wont move then you can move them. Ha! just kidding. One of the strong points to this thing is a strong piece of pine that acts as a bumper on the front end should you run into anything. You will literally bounce off.

[greenman407]

In years gone by I have accumulated pictures of many boats in many different bodies of water . Here is the Big Swamp buggy in amongst the lily pads and weeds where most boats are afraid to tread! Even on land! Is there anyplace safe???

[greenman407]

With the modification of installing a semi flat bottom a great change in maneuverability was realized. Instead of tracking as if on rails , now you could slide into a turn and spin it around in violent maneuvers that were over in a blink of an eye!

[greenman407]

Construction was a breeze. Here you can see where I have stuffed the sponsons full of A.C. insulating foam. Its now ready for paint.

[greenman407]

Here she is comepletely out of the water, in the rain. With the K&B 61 sportster engine and two blade prop it moved out well. Here is yours truly , having just started her up , getting ready to put it in the water again to assault the lily pads,,, again.

[greenman407]

Im not satisfied with the Fox .74 engine and the performance that it brings to the Swamp Buggy. NEED MORE THRUST. So im presently considering a YS-110 4 stroke engine. And to capture and utillize the extra horses Im possibly going to a 4 bladed prop to boot. Im still mulling over the prospects. In the meen time look at another possibility.

[greenman407]

Why do I need more thrust do you say? Because this boat is a tunnel hull and the weight of the boat rests on the knife edges of the tunnel. Therefore when you are running it on land it doesnt want to move. If the grass is wet then its no problem. So if im at a lake or pond and want to bring it up out of the water you get stuck at the waters edge. MORE THRUST!

[Scott T]

How about attaching some strips of nylon on the edge.
It is slick and you can slide heavy furniture on that stuff.

Scott T

[greenman407]

Thats a thought...........................but not as much fun as a new motor!

[Subculture]

Won't it get a bit unstable with such big engine up top?

[greenman407]

Subculture, good point. If you scroll down thru the pictures on the first page of this article youll see that unstable has never been a worry. In one of the pictures you can see it swaping ends under power. The only way you could flip it is if you ran into something at speed. The new engine, I believe, is in the same general weight category. One thing is for sure, were about to find out.

[greenman407]

Heres a video of a guy with his, first running on the grass and then on the water.

http://www.youtube.com/watch?v=L9b7NMMFV9g

[greenman407]

Heres another one where he went just a little too fast and it blew over. Thats the reason for the spoiler on the front of my first one and some extra weight.

http://www.youtube.com/watch?v=cPMp1ELo078

[greenman407]

Yesterday I ordered my new motor. Its a Magnum XL91RFS. Thats a four stroke glow engine. With it will come a 4 blade 11" x 6 pitch prop for a P-51 Mustang model and a aluminum spinner. Stay Tuned folks.