Dumas Hawk 3.5 new build FE Conversion

[high-tech]

Hi Guys, :help:
I'm gonna build this Dumas Hawk Brushless Conversion and I know its been done before... And I cant find any Info on past builds so I'm not really sure about motor placement... Anybody know who I could get ahold of to get me started of right? I would appreciate some help Thanks...

I'm thinking Nue 1415 or 1515 1y 2200kv 4s P Spec and play with 6s for fun... I would appreciate the feedback thanks


134833

[high-tech]

Well I got a little bit done, I may be a little slow but what's done is right! I borrowed a tub jig from a club member and got it straight!!! I feel good about it everything lined up and it's ready for the boom tube inserts that go in the tub... I'll Update when I get more, I'm waiting for hardware from zippkits.

[high-tech]

Most of the hardware showed up today and I got the Sponsons almost done... I didn't like the dumas design for the right sponson so I made a mirror copy of the left sponson and used a foam core instead of balsa wood. I still need to come up with a turn fin and a few other things like speed controller and rudder servo and some carbon fiber for the battery / motor compartment.

[high-tech]

Some more Pictures

[grsboats]

In the 90's I used to run 3,5 and 7,5 nitro Hawks.....great boats for that time......it would be nice see a brushless version...hope you have enough height to place everything.Thanks for sharing Gill

[high-tech]

Hey Gill I raised up the boom tubes so I would have room for the batteries and the motor is gonna stick up up so I'm gonna make a bump in the hatch. Nothing to radical its a 4s heat racer... Here in Tucson We have a class called open Electric, its crazy but there aint very many people here in Tucson who know how to build Fast Electrics... Our Club President has a 7.5 Hawk kit unopened and I'm gonna do that one for gas motor Zenoah G260PUM and It will be fun and competitive...
In the 90's I used to run 3,5 and 7,5 nitro Hawks.....great boats for that time......it would be nice see a brushless version...hope you have enough height to place everything.Thanks for sharing Gill

[high-tech]

I got the Carbon Fiber done and it came out good I'm happy

[grsboats]

Looking good...I'm looking forward to this project ...your motor choice is right.Gill

[high-tech]

I fabbed a servo mount and located and drilled the rudder control rod hole. The Motor mount showed up today and I think its good to go for initial testing I'm using the 2030kv ammo motor... Now I can start on the stuffing tube.

[high-tech]

Starting to look like a rigger

[high-tech]

Well I started making the hatch that covers the motor compartment... I took the original plywood hatch and glued a block of Styrofoam to it and shaped it with sandpaper and then fiber glassed over it for a parting surface and then prepped it with PVA and a couple coats of partall wax, then I wet out another piece of cloth for the hatch now in 3 hours I'll part it off the mold and trim up and its done!:biggrin:

[high-tech]

Well I got it parted trimmed up and it tapes up good I may do one in carbon too

[high-tech]

I got the stuffing tube and the motor mount glued in for good... I went to my local fiberglass supply store here in Tucson and got some fillers and some black die and that stuff turned my epoxy resin into JB Weld really cool stuff...

Fillers are Milled fiberglass Cab-o-sill and Basically talc powder, really strong stuff... I may never buy epoxy glue again

[high-tech]

I made a carbon fiber cowling and painted some accent color on the tub sides and sponson sides, I bought some automotive urethane clear and I'll give it three coats

[capnswanny]

Man, that's looking great!
I like how far forward you mounted your motor, I think that will get the cog where it should be.
I picked one up at a hobby show and converted from nitro to FE. This was my first "real" FE boat and I struggled a bit too get it to run well. My cog is still father aft than I would like and there's a lot of extra weight from the original build. I managed to squeeze out 38 mph with a AQ2030, AQ60A ESC on 4S. Got 43mph with the AQ1800, Seaking 120 on 5S. Here are some pictures I snapped for you tonight with a 5S 4000 battery in the hole:

[capnswanny]

Here's a cruddy video of my second "first" run a couple years back, with commentary provided by my son and the rest of the crew on the lake. I never fixed the hopping problem, and I took on some water knocking out the RX, but you get the idea ;)

http://www.youtube.com/watch?v=DHlEhjrHy3w

[high-tech]

I thought I was gonna have to cut that bulkhead and mount the motor like you did. I waited till I had all the hardware mounted and batteries in it and found CoG just slightly behind sponsons and that's it...
Man, that's looking great!
I like how far forward you mounted your motor, I think that will get the cog where it should be.
I picked one up at a hobby show and converted from nitro to FE. This was my first "real" FE boat and I struggled a bit too get it to run well. My cog is still father aft than I would like and there's a lot of extra weight from the original build. I managed to squeeze out 38 mph with a AQ2030, AQ60A ESC on 4S. Got 43mph with the AQ1800, Seaking 120 on 5S. Here are some pictures I snapped for you tonight with a 5S 4000 battery in the hole:

[high-tech]

what size prop did you run
Here's a cruddy video of my second "first" run a couple years back, with commentary provided by my son and the rest of the crew on the lake. I never fixed the hopping problem, and I took on some water knocking out the RX, but you get the idea ;)

http://www.youtube.com/watch?v=DHlEhjrHy3w

[high-tech]

I splurged and bought a quart of automotive urethane clear and I'll never point a rattle can at a boat ever again... This Urethane is amazing stuff I used three ounces of clear and reduced by 40% and it was perfect consistency for my airbrush came out cherry still looks wet and its been dry for a day now

[capnswanny]

what size prop did you run

This run was a m447.

[longballlumber]

That boat should run well with starting off with an H4, H5, and if temps OK H7. All in that order. With a high RPM .21 sized motor it will push that hull into the high 60's They are sweet driving hull once set up correctly. Mine is 8 years old and can still hold its own, but I run it with nitro power.

Later,
Ball

[high-tech]

Right now for starters I'm gonna run an AQ 2030KV motor and I'm starting with a Graupner K Series 42mm and I also have what is equivalent to an Andy Brown 1450 and a m445 and I can tune a prop to the boat... So I'll get up there eventually. I have plenty of room for Lipos and the next size up in motors but I think this will make a good PLtd hull.
That boat should run well with starting off with an H4, H5, and if temps OK H7. All in that order. With a high RPM .21 sized motor it will push that hull into the high 60's They are sweet driving hull once set up correctly. Mine is 8 years old and can still hold its own, but I run it with nitro power.

Later,
Ball

I got the Turnfin Bracket done today... This boat is real close to getting wet!!!

[high-tech]

Putting the finishing touches on this project... I need to fasten the receiver battery in position and build the flex and stub shaft assembly

[ray schrauwen]

Very nice build!

[high-tech]

Thanks Ray, I can't wait to get it wet...
Very nice build!

[capnswanny]

I hope you can post up a video....I would like to see how she does!

[high-tech]

I've got a decent phone I'll get some video up for sure
I hope you can post up a video....I would like to see how she does!

[high-tech]

Well I finally got to the lake this morning and I recorded the Maiden Voyage and she ran pretty good and the temps were cold so I have room for more prop!!! I was running a Graupner K Series 42mm prop 2 2S 5000mah dinogys. I'm gonna order some more Lipos I only have one pair. I'm thinking about the 6000mah 2s dinogys.

https://youtu.be/ZHi7vnCu9_s

[tlandauer]

:tiphat:
Maiden looks great! It is a wonderful build, thanks for sharing, I love everything you did, don't know how i missed this thread.:doh:

[capnswanny]

Looking good!! Thanks!!
Makes me want to break mine out :)

[high-tech]

:tiphat:
Maiden looks great! It is a wonderful build, thanks for sharing, I love everything you did, don't know how i missed this thread.:doh:
We have a retired police officer in our club and he says my dumas was doing about 52mph:banana:
Thanks tlandauer I'm getting ready to put my twist on a JAE 21 FE Kit I just bought from a fellow OSE member, he just couldn't get around to building it and he bought everything so I really got hooked up big time and of course I'll share.