1949 Chris-Craft 19' Racing Runabout by trashboat - Dumas - 1/8 - RADIO

[trashboat]

Just got my new kit in the mail. This will be my first Dumas Boat Kit . I'm a little intimidated by this kit, I've watched lots of videos and viewed lots of build logs so it's time to get cracking!

[donrobinson]

Should be a cool build, looking forward to seeing more

[GuntherMT]

Really like the looks of these boats, someday I'm going to have to build one, if for no other reason because of how the finish is done, which I've always found beautiful.

 

Good luck and have fun!

[gjdale]

Hi Trasboat (do you have a real name?),

 

I'm building this same kit, so we might be able to help each other out along the way. Lots of "firsts" for me on this one too! I'm a very slow builder (lots of other demands on my time), so it won't take long for you to catch up and overtake me. There's a link to my build log in my signature block below if you're interested. I've learned a few lessons already!

[trashboat]

Ok i just ordered a bunch of clips and The book Mahogany in Scale as everyone seams to recommend it.

I have a question are there any recommendations for a servo and radio system? I'm going to be using the dumas 6v motor.

 

Thankyou

[gjdale]

I'm new to this myself, but the advice I received was to go for a 2.4Ghz radio system (they seem to be the "standard" these days). Unless you're planning on adding "extras" a simple two channel, or three channel system will suffice. (Three channels will allow you to add lighting if you want). A simple "pistol grip" controller, like those used for RC cars, is great for this basic setup.

 

With your Electronic Speed Control (ESC), if you ensure it has BEC (Battery Eliminating Circuit) it will save you having to run a separate battery for the Receiver (it will then be powered by the main battery). There is good basic "how to" guide on electrical stuff over at the rcgroups forum:

 

http://www.rcgroups.com/forums/showthread.php?t=783582

 

Hope this helps.

[trashboat]

ok ill just use an old hobby wing I have here. Its made for brushed motors so it should work. I am big into the RC 1/10 scale short course trucks but I run all brushless and I didn't want this boat to be fast, so I opted for the recommended motor by dumas.

 

Also I've been following your build on the same boat gjdale Awesome work by the way! Now on the bottom I know its a plastic piece how did you reinforce yours if you did at all? I was read that they can split.

Edited June 17, 2016 by trashboat

[Gerhardvienna]

Hi trashboat

 

Make yourself sure, that the ESC is ready for the Ampere, the motor will need. 2.4 Ghz radio system is stae of the art, as Grant mentioned above,

The plastic part should not break, if you want to reinforce it, you could make a thin epoxi/ Glass fibre inlay. But watch out for parts you will possible need the way they are! As I don`t know the kit, I don`t know how it looks at the inside!

 

Regards

Gerhard

[gjdale]

Having read the same comments about the Sintra (plastic) opening up at the seams, I'm planning to fibreglass the exterior of the bottom as well. The instructions claim you don't need to, but I think I'll err on the side of caution with this. And I have also painted the interior with a diluted coat of finishing resin - finishing resin diluted with what I believe you call denatured alcohol in the US, or Methylated Spirits (Metho) over here. The advice from the guy in my local hobby shop was to add just enough Metho to make the resin the consistency of paint. I had no problem following his advice, but haven't given it a water-tight test yet.

[trashboat]

Ok now the instructions stated you couldn't fiberglass /resin the bottom because it may melt. If anything ill do like you said and just epoxy with a thin layer on the inside.

[trashboat]

As of right now im just getting all my ducks in a row getting all the parts and materials I need to get her rolling. AS soon as the book comes in ill be reading that but I think I got a bad seller on ebay should have read the reviews first may have to reorder it from amazon this time.

[trashboat]

Oh also to a previous comment my name is Paul.

[gjdale]

I think that's a wise decision to wait for the book Paul - it's got some great advice, especially for those of us new to this form of modelling. It also suggests a few different build sequences to those described in the instructions. I've certainly found it invaluable so far.

 

Interesting comment about fibreglass/resin reacting with the Sintra. I don't recall reading that in the instructions but will have another check. There was certainly no reaction between the resin and the Sintra on the inside of the hull. I guess it always pays to do a test on some scrap material before diving in with the finished product!

Edited June 20, 2016 by gjdale

[trashboat]

Most of the suplies came in today, im not in a hurry to get the remote just yet if anything I can test it with one of my truck radios.

[trashboat]

I dont have a scroll saw so i was recomended to use a hobby saw so we will give it a try.

Edited June 20, 2016 by trashboat

[Thistle17]

Paul I built this boat with my grandson over last fall and this winter. We are presently at a stage where we need to coat the upper body with a clear coat. It will be a pretty model for him and should be fun to use. Anyway I don't want to dismay you, rather I think alert you that the kit I bought for him had die cut bulk heads which were not very well made nor accurate. Use a batten to true them up. Secondly they were a bit on the thin side so we added 'beef" to some to get a good landing surface for the PVC substrate. The next problem I have never understood was that the PVC substrate elements did not conform well to the bulk head to yield a completely closed hull. The hull planking went fairly well without much fuss save the fact that some planks did not easily match up with the former applied plank. Some sanding and some fill was needed. I highly recommend that you outfit the engine compartment early on while you can get at things. Also the rudder compartment. You can remove the parts while building , but plan your mounts like battery, switches, ESC etc. One last thing we used the foil that came with the kit to cover the rub rails and cut-waters. It did not go well. I have seen one other method that applied the material after the rub rail was on the boat. For the life of me I cannot understand how he got it to lay well and trimmed. I gave up and have made an MDF contoured board to which I am pinning 1/2 round styrene to and coating it with the foil. BTW since I screwed up the original foil I purchased anew at the hobby shop. It was of thinner gauge and ripped easily. So I ended up using aluminum heating duct tape. It is more sturdy. Again a fun kit to build especially with my grandson. Good luck. Hope this helps..

Edited June 21, 2016 by Thistle17

[trashboat]

awesome thank you for the tips I will defiantly be looking out and planning ahead!

[trashboat]

Did i make a mistake in buying a standard sized servo? Dumas stated that a HS311 would work i have the carbine version of it the HS322, but ive seen on other peoples builds they are useing micro servos. Will a standard size be an issue?

Edited June 21, 2016 by trashboat

[Thistle17]

Paul it is pretty tight under the rear seat compartment. I had to drastically hollow out a channel on the underside of the seat cushion so that the bell crank attachment to the servo would move freely. The bell crank arm is almost vertical and this was to get the rudder to move fully left and right. This was with the micro servo so I am guessing that the larger size is going to give you trouble.

[trashboat]

OK I will be returning it then, now what servo did you use if you dont mind me asking?

[Thistle17]

Paul unfortunately I tossed the label wrapper for the servo but I do know it is a Traxxas water proof micro servo. https://www.amazon.com/Traxxas-2080-Micro-Waterproof-Servo/dp/B002BE8672 isa link for a similar unit on Amazon. i do not recall it coming with a bell crank so check your accessories before you order anything.

[trashboat]

Started it up yesterday my biggest problem was the butterfly that was a pain! But got it done. More to come today.

[trashboat]

Ok thank you Thistle.

[trashboat]

Im a little stuck on the chine Rail. In Pattricks book it says to sand flush with the beams, But instructions say not to destroy the outside edge and you caint make it flush without destroying the outside edge I'm not sure on how to go about sanding this thing.

[Thistle17]

Think of it this way. You are going to lay down a layer of PVC clad and the definition of the "lines" of the hull will be defined by the fit. So with careful sanding you need to get a good solid intersect of the sides and the bottom. I wish they would modernize this kit and laser etch the parts. This would help and avoid the problems I am sure many of us have run into.

[trashboat]

Ok I got got it to fit ok, now I'm worried that when I lay and glue the two sheets of abs there will be a large gap down the middle at least up front I'm really trying to avoid splitting this thing when it hits water I really don't like this plastic.

Edited June 23, 2016 by trashboat

[Thistle17]

Paul, you will find some places where the fit isn't exact. Whether down the seam, amid ship, or at the chine or bow. What we had to do was ensure as good a fit as possible. Gluing in "fillers inside if we had an unreasonable gap and filling all seams that were not quite right with EverCoat  2 part compound (use the blue hardener) . It adheres great and sands well. It's par for the course with this kit. There is no way that all of the parts fit like we all wish they would.Its the nature of the kit. I have built all types of models and I found this one to be a challenge due to parts, multi media material, using the wrong CA glue (low viscosity version was overused), used auto body resin for the uppers top coat (had to be sanded off #!?$!!!!). Well you get the idea. And, oh yeah, i didn't look like a "cool" grandpa with my grandson at times.

[trashboat]

haha alright, Well I finally got it to were I want it I ended up cracking in trying to lift after it was glued luckily it wasn't major and just CAed it back together. I have some aves putty here i may use or just go with good ol bondo im working on sanding down all the edges now before putting on the side panels.

[trashboat]

Also you are supposed to sand the edges flush to the chine with a curve of the sides Correct just making sure I read that right , if not I'm in trouble haha.

[Thistle17]

I am not exactly sure what you mean, but if I perceive what you are asking I will answer this way. You must sand the sides flush with the bottom. The planking will reach all the way to the chine and the bottom, as stated, in the Dumas directions does not get (or need planking). The same sanding advice goes for the deck and sides intersection. Pay attention to the bow as well for a nice smooth intersect and that it is as true in sweep as possible. One last thing the PVC clad as it nears the bow at the chine was not a smooth transition because of the twist it has to make. it required some fill (not much). Don't forget to rough up the clad material before CA ing the planking.