help needed in finishing boat

[R.J.West]

I have a Dumas Miss unlimited shovelnose hydro that has been sitting in my closet half finished. I tried to modify it for electric but changed my mind in the middle of the build and went on to other projects. The boat is 36inches X 15 inch beam. It was originally designed for tether racing with a .35 - .40 nitro motor. Far as I know Dumas stills sells them only on their website.

I am going to finish the boat for use in the sport 40 class. The only mod I done was to remove the two inside stringers for the motor mount. I have an idea how to mount the motor, Iam just trying to get more ideas on how to finish the boat. Has anyone out there built this boat?

Thanks, Ron

 

[R.J.West]

I guess maybe the Dumas Miss Unlimited is not the hot topic like it may have been 40 years ago.

 

[dannyual767]

Ron, I'm sure you've seen this thread from the General Boating Forum:

http://www.intlwaters.com/index.php?showtopic=15881

Its loaded with good info on how to finish wood hulls. I love to build wooden hulls and have 4 of them that are sealed with epoxy resin right now. I just spent over 100 bucks on PPG Omni automotive paints to finish these and my fifth hull, a rebuilt, fiberglass Aeromarine Avenger cat.

 

[R.J.West]

Basically what Iam looking for is advice on which hardware to use, how to use it ect... for an sport 40 shovel nose hydro.

The boat originally designed for a straight 3/16 driveshaft and fixed, non adjustable strut. I got the hardware kit from dumas, it is very basic. Almost cavemanlike in quailitity and design. I have an additional kit from dumas, a no. 2356 designed for the sport 40´s. and I have been considering ordering a strut and rudder from speedmaster. The wood in the kit was the exact opposite of the U-76 kit I almost finished. None of the parts fit right, not even close. It took alot of carefull planning and work to build this thing right. Its still not finished. What is done so far is I have the hull done except the deck. I made cut outs in all bulkheads to try and lighten her up. Next I am going to add inside stringers so that there will be sealed compartments inside. When the cowl is popped open there will be just the center open for the radio box engine ect.. So far the hull sits even on my glass table no warps. The kit comes with really nice mahogany decks. I am going to dedicate this boat to my wife. ( :lol: Iam trying to kiss her butt guys, its an expensive hobby! :lol: ) I plan on painting the sides and bottom hot pink, finish the top deck in mahogany and paint the cowl pink and slap on some white lettering that says ¨Miss Silvia¨ ( the boss´s name ). B)

 

[Wesleys Custom Graphics]

My sport 40 is named Jill Ellen but I still cought heck over spending the money.

Take my advice and pitch that old Dumas hardware away and find a GOOD boater in your area who can help you retrofit GOOD hardware like Aeromarine and speedmaster. Yes its alot of money but you will have alot fewer problems later at the pond. I used to have one of those boats and I still think it would make a neat sport 40. The boat is alot taller than a conventional boat but the one I had was verry light. At the very least it will be pritty with that cleared woodgrain finish.

 

[R.J.West]

You are Soooo right about the weight, or lack of. The basic hull as it is now without the decks on is about 1.5 - just under two pounds. Remember, I cut out all the bulkheads with my Dremel tool to lighten it up. I am going to add stringers on the inside to strengthen the hull and try to slow down its progress as it is being slowly devoured by the pond monster! Other Than that I estimate the boat when finished to be well under 7 pounds when finished.

Ron

 

[dannyual767]

Definitely ditch the Dumas hardware! Don't even think about running the straight shaft unless you're a total "old school" diehard!

I've got an unbuilt Dumas 1/8 scale Miller American hydro and it was designed with the straight shaft drive system . I called Dumas and they admitted that they shoulda designed it with a flex drive. They said that it wouldn't run right with today's high output 11cc engines. The straight shaft would force the nose down way too much.

I know that many of these Dumas kits were designed way, way back when. They were designed around what was available back then. Today, we are way past that old technology. I've got a Dumas SK Daddle that had to be designed back in the early 60's ! You ought to see the pictures of the radio they used! You ought to see the pictures of it running! I'm sure it was going all out and it's not even on plane :lol: ! I think a tightly wound rubber band would've offered more speed!

You are Soooo right about the weight, or lack of. The basic hull as it is now without the decks on is about 1.5 - just under two pounds. Remember, I cut out all the bulkheads with my Dremel tool to lighten it up.

These Dumas boats have a reputation of being on the heavy side. You've helped by cutting lightening holes. I did some of that on my SK. Not slopping on big globs of epoxy glue helps as well. My SK has started to gain a fair amount of weight now that I've epoxy sealed the inner hull and glass covered the outer hull. I've been using a kitchen scale and the hull is weighing in at about 2 lbs 12 oz right now. I estimate that the final weight of the primed, painted and clearcoated hull should come in right at 3 lbs.

 

[R.J.West]

I built the Dumas 1/8 Miller American back in 1989, it was a real chore! Iam working on two projects right now. One, I am finishing up on the cowl and starting to fill holes on my Dumas U-76 sport 40. And whenever I have the time I do something little to my ¨Miss Silvia¨.

On my U-76 sport 40 I got alittle carried away while attempting to drill out the holes I made to mount the strut. The F´N drill took off on me and made the holes much bigger :angry: . Theyre suppose to be about 5/32 countersunk but I made two of them 3/16 to 1/4 inch. OUCH. The only thing I thought of was to tape the inside and pour 30 min epoxy on the outside and just redrill the two holes. I hope that was the right way to correct that.

Ron

 

[dannyual767]

I built the Dumas 1/8 Miller American back in 1989, it was a real chore!

Can you tell me more? I know that this is going to be a tedious build. The box looks like it contains 2 or 3 full sized trees :lol: . I built the jig for it about 2 yrs ago. I've had to true the jig up once already since this humid Florida weather caused it to warp just a little. I need to true it up one more time and seal it with my epoxy sealing resin and be done with it.

Do you remember how much your bare hull ended up weighing? If I remember right, Dumas told me that some boats come out real heavy, like 17 lbs ready to run so one has to be extremely careful to try to keep the weight down! I love the challenge of trying to keep a build nice and light !

 

[R.J.West]

That was quite a while ago, but bear with me.

Do make sure your jig is straight and true. What I have always done was to sand down all parts while still in the carriers sheets before snapping them out. Some parts may not be cleanly die cut and the sanding helps alot! I use 220 grit. The basic hull went smoothly as I remember it, The cowl I had to take my time with cementing all those little vents in place. The only pain I remember was the front canard wings and the nose.

You want to talk about weight? Well I used regular car Bondo to build up the nose, DONT DO THAT. :lol:

You have to remember I was just outa high school then and still learning. For the nose I would consider using a piece of pine and carve that into the nose. The cancard wings were tedious. They are non adjustable as designed so make sure they are as Dumas reconmends. Here are my reconmendations, make cut outs on all bulkheads to lighten it up, except dont accidentally make cutouts on the sponson transom!

I use 30 minute epoxy thinned with rubbing alcohol and brush it inside to seal the wood, I do a couple of coats at least. I would spread epoxy on the underside of the decks before attaching to prevent any ¨dry spots¨. The real chore was all the friggin sanding, sanding, sanding I had to do. Then all the preping, sealing the wood ect, and more sanding. I quess Its o.k. to use the Dumas rudder and water pickup, but dont use the straight hard drive shaft set up, I would use a strut and flexshaft from some other company.

Hope this helps!

 

[dannyual767]

You want to talk about weight? Well I used regular car Bondo to build up the nose, DONT DO THAT. You have to remember I was just outa high school then and still learning.

Ha Ha! Its funny that you had the same experience that I had! The first powerboat that I ever built was the Dumas Pay N Pak .21 kit. I was in the 10th grade back in the late 70's and I used Bondo to cover all of my building sins . It was so easy to work with and, of course, easy to sand. Today, I stay away from it like the plague but I probably should use it in some cases. I think that if it is very thin, like maybe filling pinholes and such, it isn't a problem. I even bought some Bondoglass about 6 months ago that I still haven't even opened up.

....make cut outs on all bulkheads to lighten it up, except dont accidentally make cutouts on the sponson transom!

I plan to do this to save weight but I'll be extra careful not to cut out the sponson transoms!

I use 30 minute epoxy thinned with rubbing alcohol and brush it inside to seal the wood, I do a couple of coats at least. I would spread epoxy on the underside of the decks before attaching to prevent any ¨dry spots¨.

I have a great, thin penetrating epoxy called Low V that I mail ordered from a company called Progressive Polymers (www.epoxyproducts.com) who sell epoxy products for full size boat building. It is fantastic for sealing wood as that is what it is designed for. The only downside is that it takes a solid 24 hours to cure. When I decked my last 2 monos, I spread 45 min adhesive epoxy on the undersides to make sure that they were sealed and so that there would be plenty of adhesion.

I like to continuously weigh my hulls so that I can keep track of how heavy they get. I'm looking forward to building the Miller American this coming winter. I'm not sure how light I can get it but I know that every ounce that I can keep off of it will result in a better running, faster boat!

 

[R.J.West]

Yeah I had the same idea about the bondo. Its a universal fix er upper all right!

I plan on purchasing a 1/8 Miller American soon. May I suggest that we share our build together?

I also have another thread thats had no bites in alwhile, its about the Dumas U-76 sport 40. I work as an OTR truck driver and one of the great things about the work is that one has, literally all day to think. In my case I think about how to build and finish my boats. Still took me two months to come with an idea to install a motor mount in my Dumas " Miss Unlimited".

 

[dannyual767]

I don't plan to start work on my Miller American before this winter. I've got way too many house projects going on right now so the middle of the winter would be the earliest that I see myself starting on it.

I think that it would be a great idea if we work on these things "together" and share our "notes!" It can help us each get past the inevitable bumps !

 

[R.J.West]

I finally treated myself to a new digital camera.

here is a pic of the unfinished hull..

 

[R.J.West]

Sorry guys, for some reason it wont let me post. P.M. me and I can send a photo of it,