Dumas Drag'n Fly 40 - Vintage Build
 

We'll after being out of the sport for over 30 years, I've decided to "re-enter" by building a vintage Dumas Drag'n Fly 40. This was one of the boats I ran back in the day so I thought it would be fun to build one of those again.

Project: Dumas Drag'n Fly 40
Power: O.S. 46VX-M ABC Marine, Mac .45, or CMB .45
Radio: Futaba
Running Hardware: Octura and Speedmaster ( I'll list the part numbers as the build progresses).
Boat length: 36"

I ordered the boat from Dumas' "discontinued" boat line but they had one in stock and I just received it last Thursday. Price $53.00. This is the blueprint for the boat. The instructions that come with the kit are minimal.

http://hydroplane.maxxipower.com/dra...0blueprint.jpg


I'll probably make a few modification to the design. Maybe a Wing?? Also instead of the full length cowl I'll probably cover the engine and radio compartment, tapper it down towards the rear and eliminate the fin. I think this will give it an updated look.

http://hydroplane.maxxipower.com/kit.jpg

Big box o' wood - Most of the pieces are cut from birch ply in various thicknesses.

RE: Dumas Drag'n Fly 40 - Vintage Build
 

FastKat, How does that plywood look ? Any Dumas ply? Another discontinued" boat . A new Iso motor mount will help with noise. hardwood mounts Old School . a good size hull 36" have fun ,will watch along with the build. Also new ply will help the transom ,No Dumas PLY on transom. I am sure you will hear about [light ply ] He will fill you in .

RE: Dumas Drag'n Fly 40 - Vintage Build
 

Week # 1 - 6/21/2009

Cut out the bulkhead pieces and sponson sides. Dumas uses a punching method instead of laser cutting. Of course they hadn't punched deep enough so Ihad to cut out each piece which took a couple of hours. Also Itraced each bulkhead to poster paper for future reference. Overall they came out ok. Istill need to trim some of the centers out of the larger bulkhead pieces to reduce some weight.

http://hydroplane.maxxipower.com/week_1_2.jpg


http://hydroplane.maxxipower.com/week_1_3.jpg

Problems
-
1.) Punching depth.
2.) Dumas plywood quality. Ibelieve the "dryness"of the ply is attributed to the ageof the wood?Dumas is in Arizona and who knows how old the wood actually is.

RE: Dumas Drag'n Fly 40 - Vintage Build
 

Good suggestion, I'll definately look into a decent motor mount and use "new" aircraft ply for the transom.

RE: Dumas Drag'n Fly 40 - Vintage Build
 

Hey Fastcat, I remember that boat when I was a kid ...never did get it though http://www.rcuniverse.com/forum/js/f...sappointed.gifgot the 1st of the Hotshot models instead, outbroads looked easier than setting up all that hardware. Have been flying planes and heli's for a long time and have been thinking about getting back into boats myself. Went on the Dumas site, was thinking about getting the Drag'n Fly or the Miss Unlimited but have no idea of what hardware to use. The Dumas hardware looks cheap and not up to the task. So I was hoping for some help with selecting the right hardware . I'm glad I ran across your build. Will be looking forward to see your Drag'n Fly take shape. Any help from you or anyone in RCU would be great !!!

Have a GREATbuild !!!!!!!http://www.rcuniverse.com/forum/js/f...sn/biggrin.gif

Jose'

RE: Dumas Drag'n Fly 40 - Vintage Build
 

I have 2 dragon flys now a 60 and a 40 bought both off e bay.
the 60 is in primer and will get paint very soon I just bought the 40 off e bay today and as soon as I get it Ill post some pics of the rebuild.It will get a new engine,radio,and running gear.

Check out top secret boats for running gear they make some really nice stuff and its very resonable..

Yall HAVE FUNNN and take care

RE: Dumas Drag'n Fly 40 - Vintage Build
 

Jose8986 - Iwouldn't use Dumas running hardware. There's alot better stuff available. Top Secret or Speedmaster are two manufactures.

Speedmaster- http://www.rossisales.com/ruddernew2.html

Top Secret - http://www.topsecretboats.com/sport_hydro_hardware?b=1

I'm building this Drag'n Fly with the "old style" solid shaft drive and universal joints. I'm using Octura hardware. I'll list all of those part numbers, with pics,when I have the parts in hand. Most boats these days use cable drive hardware and the two manufactures above will have what you need.

srw1960 - Good Luck with your restorations. Definately post some pics when your Drag'n flys are painted.

RE: Dumas Drag'n Fly 40 - Vintage Build
 

I will go along with Fastkat, speedmaster on the hardware. or another site. http://www.aeromarinerc.com/index.ph...tpage&Itemid=1

RE: Dumas Drag'n Fly 40 - Vintage Build
 

I have given a thought about using one of the old steerable outdrives on one.

I know they tear up universals but curious how that type of drive would work. I bet it would turn more solid.

Probably would be more suited to a big SKDaddle.

Not sure, I just think this is a pretty cool piece of hardware. If a cowl was built to put on top of it, and a hollow driver figure put over the engine and the pipe kept down the middle, you could pull off an outboard look with inboard performance.

I might be building my cockpit sides and front cowl like the green boat. It will trap less air or be less prone to blowover with the blunt leading edge farther back, and the cowl deck curve can be played with to help with downforce and I'm building a rail system for the tank and radio box to help set the balance.

RE: Dumas Drag'n Fly 40 - Vintage Build
 

nice looking green hull jetpack , is that a mercury engine?

RE: Dumas Drag'n Fly 40 - Vintage Build
 

Thanks Fastcat and ADVANCED BUILDER for your help will take a look at those sites. Please post the part numbers when you get them that would be great!! When I decide which boat to build I will be happy to post pics. Again thanks for your help and build. :D


Jose'

RE: Dumas Drag'n Fly 40 - Vintage Build
 

jetpack - That's an interesting outdrive. Can't say I've ever seen one of those. I guess it would be important to limit the amount of steering to ensure the universal wouldn't bind. It's pretty nice, the best of both worlds. Nice green hydro, pretty cool ride.

I'm using a solid strut with universals like on the blueprint( bottom right corner ). It worked pretty well when I used that setup before.


jose8986 - I'll definately post the pics and pn#s of those parts when they arrive.

RE: Dumas Drag'n Fly 40 - Vintage Build
 

Yep its a 35hp Merc with a Quicksilver lower unit, meaning it is a short shaft version for racing and it is mounted on a Hedlund hydro.

RE: Dumas Drag'n Fly 40 - Vintage Build
 

It is an old Octura offering which they have dropped from their lineup. I would probably think trim changes would be hard to pull off also because doing that changes the length needed for the driveshaft assembly, or at least the angle of the stuffing tube.

Probably just a mount and drive and live with what it gives you because any height changes or angle would involve sliding the motor front to back, and also moving the stuffing tube as I already mentioned. I would think after you get that all shook out it would be a decent setup, and yes...turning limits would really have to be watched.

RE: Dumas Drag'n Fly 40 - Vintage Build
 

This is a pic of the engine that came in my 40 dragon that I received today.it seems to be sound and has good compression its a ringed engine that looks to be very similar to a webra..it is marked with a HP on one side and 40, made in austria on the other..any ideas who may have manufactored it???THANKS...Also has a tube coming off the crankcase I cant figure out what its for unless maybee a vacumsource for a fuel pump ..

RE: Dumas Drag'n Fly 40 - Vintage Build
 

Week # 2 - 7/3/2009

This week I fabricated the Jig that the hydroplane is built on. Basically it's just 3/4" pine cut, glued, and nailed together according to the blueprint. There are six risers that have to be cut out of 1/8" ply and glued to the floor of the jig. These hold the boat at the proper position while the bulkhead pieces are being glued.

http://www.maxxipower.com/hydroplane/jig_001.jpg


The strut hardware also came in this week. I'm using Octura running gear. Not shown in the picture is the stuffing box, main drive shaft, and universal for the engine. I haven't decided on which engine I'm going to run yet which will determine the engine universal threads. The Octura part numbers, for the parts shown, are listed below the pictures:

Assembled:
http://www.maxxipower.com/hydroplane/strut_assembly.jpg


Components:
http://www.maxxipower.com/hydroplane/strut_parts.jpg


Part Numbers:
-
1.) Strut Blade - DVBO - You must use the non-profiled strut and profile yourself. The profiling on the DVMBO strut is too high to allow sealing to the bottom of the boat.
2.) 3/16 Hardened Prop Shaft w/drive dog - OC6PSH
3.) Needle Bearings for Strut ( Two Needed ) - OC6NE
4.) Universal Joint ( Strut End ) - OC610F/M
5.) Ball Thrust Bearing-OC6TB
6.) Prop Tail Nut-OC6PNMU
7.) Propeller-X452/3 ( This is just a starting point suggested by Octura )


This is the radio I'll be using. It's a Futaba Skysport FM I already had from a plane I built awhile ago.

http://www.maxxipower.com/hydroplane/radio.jpg

RE: Dumas Drag'n Fly 40 - Vintage Build
 

Needle bearings need a lot of attention,dry & oil ,at the end of the day.Them old school hardwood motor mount gotta go ,http://www.cmdracing.com/updated/hardware.htm

RE: Dumas Drag'n Fly 40 - Vintage Build
 

Fastkat,

that skysport FM radio, is that a 72mhz?

if it is a 72Mhz FM it is intended for plane only and cannot be used for land or water, if its a 75Mhz, than forget what I said :)

I think the SkySport 4 was available in both 72 and 75Mhz

Dan.

RE: Dumas Drag'n Fly 40 - Vintage Build
 

It's 75MHZ so I should be ok.

RE: Dumas Drag'n Fly 40 - Vintage Build
 

Cool.

Dan.

RE: Dumas Drag'n Fly 40 - Vintage Build
 

This is an HP 40 made originally as you state in Austria. They are still manufactured in several versions by MECOA http://www.mecoa.com/hp/index.htm which may be helpful.
I have recently rebuilt a 60 which is in a 42" Fairey Huntsman.
As received it had a strap on exhaust manifold with an accompanying 1/4 pound of silicone!
http://lh6.ggpht.com/_XuA0NMLYOxg/ST...2/DSCN1133.JPG

After stripping and rebuilding it has a permanent manifold fixed with JB Weld and two screws.
http://lh5.ggpht.com/_XuA0NMLYOxg/SV...2/DSCN1171.JPG
http://lh4.ggpht.com/_XuA0NMLYOxg/SV...2/DSCN1169.JPG

I think you will find the tube coming off the crankcase was for using crankcase pressure to pressurise the fuel tank a method now well superceded by using exhaust pressure.

My 60 is the first HP owned in a long line of engines - mainly aircraft - but I'm told that they were very powerful for their day and pioneered schneurle porting.
It hasn't been run yet but that's not far off as the Huntsman is in the 'paint shop'

Regards - Ramon


FastKat - Looking forward to following your thread, I'm a thirty year ago 'returnee' too. Kep the pics and info coming, it's all interesting and informative

RE: Dumas Drag'n Fly 40 - Vintage Build
 

Ramon - Nice job restoring the HP 61, It looks brand new. Post a picture of your boat. I would like to see what a huntsman looks like.

RE: Dumas Drag'n Fly 40 - Vintage Build
 

Nice old little engine for sure.

I would like to point out that there are still some people using crankcase pressure to keep the fuel system pressurized.

Fastkat, will be watching your build, pretty interesting.

Dan.

RE: Dumas Drag'n Fly 40 - Vintage Build
 

No offence Dan, I'm sure there are , just that most seem to go the exhaust route. At one time some engines came with a nipple to screw into the backplate mounting hole that had been drilled right through, not sure if that still occurs - it's been quite a time since I bought a 'new' engine.

Fastkat, I 'involuntarily' packed up boating in the seventies when I went overseas to work. At the time I was very keen on going to the 'next stage' and building a hydro of some kind but personal circumstances dictated otherwise. A year or so ago I was asked to help sell some boat engines for a friend who had died. All were NIB except two the HP and an OPS both in a neglected state. I bought a couple of the NIB's and the OPS and was given the HP for my troubles. Went to the local water to try to see if anyone was interested in the other engines and got instantly hooked. I was running an OPS in the seventies and thoughts of a hydro resurfaced but watching the speed of some of these boats I felt I had better take things a bit steady. Hence the Huntsman, with a hydro following on close behind for when I have my 'hand in'. All my future thoughts on boating revolve around hydros though.

Currently being painted here is the last pic of it (the bottom was primed before I worked on the topsides)

http://lh6.ggpht.com/_XuA0NMLYOxg/Sj...2/DSCN1511.JPG

Progress on the Hydro is on the 'First Hydro' post.

Keep on with yours - as we get older a good dose of nostalgia is a real tonic.

Regards - Ramon

RE: Dumas Drag'n Fly 40 - Vintage Build
 

Ramon,
no no, no offense taken.
I agree with you, the majority of us pressurize the tank by the exhaust. Just saying that there are a few people that still prefers pressurizing their tank using crankcase pressure, and some of them go as far as making the hole on the back plate (on new engine).

Dan