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1949 Chris Craft 19' Racing Runabout by gjdale - FINISHED -Dumas - Radio - 1:8 Scale

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I bought this kit about two years ago, having been enamoured by the excellent build log of Rusty on MSW 1.  Sadly, that build log disappeared with the “great crash”, although Rusty did re-instate the photo sequence from his build.




This kit represents a couple of “firsts” for me.  First up, I’ve opted to go with making this a working radio controlled model – something I’ve never done before, but the Admiral thought it might be a bit of fun and so in a way this is “her” boat.  We have a pond/lake nearby and some grand kids that might also enjoy taking her for a spin (if they can wrest the controls from the Admiral, that is!) Secondly, the building of this boat calls for the use of fibreglass – something else I have never done before.


What's in the box?


The kit contents are interesting and appear to be generally high quality.   There is a mixture of die cut and laser cut parts, Mahogany strip wood, cast metal fittings (with what appears to be nickel plating), a type of plastic board (which forms the hull below the waterline), some aluminium strip (for the trim), and some styrene strips (that form the “caulking” for the deck planks).  The kit also contains all of the running gear required to make the boat operational, minus the motor, battery and RC units. These I bought separately at the time that I bought the kit.  The propeller supplied is a two-bladed plastic one, so straight up I opted to purchase a replacement three-bladed brass one (you can just see this in the centre of the photo below).




A set of decals, a full size plan sheet, a collection of building diagrams and what appears to be a fairly comprehensive instruction manual complete the contents.  I had also come across a book titled “Mahogany in Scale” by Patrick Matthews, which is meant as a generic guide for modelling this style of boat, but uses this exact kit as the example throughout.  Having read it from cover to cover (twice), it will be a great reference throughout the build.




Construction - First Steps


I also found a number of build logs of this kit on an RC forum (including one by Pat Matthews) and have already come across some interesting ideas for modification.  A common complaint among other builders has been the use of a decal strip for the instrument panel.  I have already decided that I will replace this by making my own instrument gauges.


So oddly enough, having cut out a build board to commence the project, I decided to start the build by doing a “proof of concept” for the instrument gauges.  It took a little trial and error with the lathe, but here is a sample of what they might look like. I forgot to add a scale reference, but this is one of two smaller gauges that will be about 12mm external diameter.  I have bored out an inner section to a 10mm diameter, into which a gauge face will be glued, and I have cut a shoulder and bezel to allow it to be mounted through the dash board.  The one larger gauge will have a 16mm external diameter with 13mm inner section.






I have found a few pictures of appropriate gauge faces on the web, and will probably draw my own in CAD based on these. Of course, my mate Mobbsie is now trying to convince me to add LED lighting to these……………..



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Thank you very much Brian, Mobbsie, Bob, Rusty, Jerry and Sy, and of course, all of the likes.


I am constantly in awe of the generosity of spirit of the modelling community and would like to pay tribute to two special gentlemen.  


Firstly, our very own Rusty, who PM'd me recently to offer to send me his copy of the Dumas DVD on finishing techniques.  An offer that I might add, I accepted with grateful alacrity - it might just get me through the fibreglassing stage!  Thanks ever so much Rusty! :) 


The second acknowledgement I'd like to make is to someone who, to my knowledge, is not even a member of this Forum.  That gentleman's name is Mr Ken Foran.  Ken is an expert modeller and is the designer of the Model Expo Allerton Steam Pumper kit.  A little while ago, I bought this kit when ME had one of their 40% off sales (I know, I'm weak, I couldn't help myself).  When I sent a query to ME Customer Service regarding something in the instructions, they kindly put me in touch with the kit designer, Ken.  I have since had an ongoing email dialogue with Ken, who it turns out has also written a book "Model Building with Brass".  This book is an absolute beauty! Not only does it provide lots of tips and techniques that are applicable to model ship building, but it is packed with beautiful colour photographs of Ken's work - a great coffee table book as well as a must-have reference book.  Anyway, it was reading his book that prompted me to have a go at the instrument gauges for this build and Ken has patiently answered my (several) email questions about how to go about this, including tips on cutting techniques and achieving a highly polished effect.  Thanks Ken! :)


Right - on with the show.....


Construction: Gauges


Having successfully competed the “proof of concept” for the gauges, I went back and turned up the final versions, adding a few improvements as I went.  In particular, I made the “undercut” behind the gauge more substantial to help with mounting, and I put a bevel on both the inside and outside of the outer ring.  Before parting off from the lathe, I used a succession of finer grit sanding pads, and finally some metal polish to achieve an almost “chrome” finish. In the pics below, I've included the original "proof of concept" test to show the difference in finish achievable:






Browsing the RC Forum, I came across a set of gauge faces that someone had drawn up and posted, so I “borrowed” these rather than re-inventing the wheel.  After a little trial and error to get the sizing right, I printed them up and have just temporarily placed them in the gauge faces for a “test fit”.  At the moment they are just printed on plain paper.  In the final version I may print them on photographic paper.  Further testing to be done yet.




Given that the larger of the dials is just 10mm in diameter, I think these look acceptable. I have a plan for the gauge "glass" - coming to a forum near you soon........................

Edited by gjdale
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Thanks Mobbise, Mark and Ben.


A minor update tonight......


Construction: Gauges continued


Continuing development of the gauges, I came across another idea from the RC Forum – instant domed gauge glasses!




Yes, they’re “googly eyes”.  A few minutes on the sanding block to remove the backing and reduce the diameter to just fit the gauges and you have:






The plastic is not quite as clear as I would like, so not sure yet whether I’ll go with this in the end.  I have another alternate method to try yet……..

Edited by gjdale
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The gauges have now been set aside for the time being.  The final version will be dependent on some lighting I plan to add, so will wait for some of that to arrive before going any further with these.  In the meantime, it was time to start construction proper.


Construction: Frames and Keel


The frames are all die cut balsa ply.  The die cutting requires a little more effort to release from the layout boards than does laser cutting, and the edges are nowhere near as neat.  However, after a couple of hours of cutting out and cleaning up, we were ready to begin.




Four of the frames have reinforcing strips around the edges, so the first job was to glue these up:






Frame Four is also drilled to accept the steering column, and has a support installed on front (bow) side of the frame:




The Forward keel extends from the bow to Frame Four, and is comprised of two identical parts epoxied together:






The sub-Deck provides a flat surface on which to assemble the frames.  It comes in two parts which are joined together over a sheet of grease proof paper on top of the building board. (The grease-proof paper is to ensure that the sub-deck doesn’t accidentally get glued to the building board!)




Continued next post......... 

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Construction: Frame, Keel and Chine Installation

The frames are then installed, with the aid of a special template jig as they are not perpendicular to the sub-deck. When installed correctly, they have a slight lean aft. Epoxy is the recommended glue for this job. I used the 5-min type and it was quite good to work with, having a reasonable working time to get things aligned correctly, and then setting reasonably quickly after that.


Once all the frames are installed, the Fwd keel is inserted. I used Epoxy to glue the forward part to the sub-deck, and then wicked super thin aliphatic resin into the frame joints.


The next job is to insert the Butterfly Keel, which is a two piece keel (one either side of the centreline) extending from Frame Four aft to Frame Eight. Once that is installed, the next job is to install the Chine. This is an interesting construction method. The Chine is made of two 1/8” thick strips of balsa on each side To start, the ends of the two strips are glued together for the first inch, with about 1/4" overlap. Once dry, this section is then glued into the notch in frame one, using a liberal amount of Epoxy and left to cure for at least one hour.


Once the epoxy has cured, a bead of wood glue (I used the aliphatic resin again) is run between the two strips, and these are progressively bent to shape, clamped and glued to each frame notch in turn with thick CA and the assistance of some CA kicker. Sounds complicated but is remarkably easy and all done in about 5 minutes.


Once all the glues had dried, the overhang was trimmed flush with the transom.


This completes the lower hull framing. The next job will be to install the “underplanking”.

Edit: I may have been mistaken about some of the materials used. See post #19 below for further thoughts. Edited by gjdale
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Looks like a great start Grant, quite nice to see a very different sort of boat being built.


How do you like working with balsa pieces for the framing?  I don't care for balsa as it's so soft, but I've not built a kit with any included, only used it for filler blocks (which I've switched to basswood for).


Looking forward to watching the planking go on!

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Augie - welcome aboard my friend. Great to see that you found your way over here. Grab a drink form Mark at the bar and pull up a chair.


Bob (Hexnut) - thanks for the tip re plastic polishes. That particular product doesn't ship to Austalia, but I'm sure I'll be able to find something similar in an auto parts shop here.


Brian (GuntherMT) - I may have been mistaken over some of the materials used. According to the instructions, the frames are allegedly Mahogany Plywood. I don't think so, but could be birch or basswood (?) - they are very light. Also the Chines and Butterfly keel are listed as being Poplar - maybe, but again they are very light (which is why I may have incorrectly assumed them to be balsa). Comparing these materials to that which IS listed as balsa in the manual, there is a difference, but not much. The exterior planking is definitely Mahogany though :)

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Grant, I have seen this beauty at several runs and at Manitowoc several times. It makes up into a very nice and classy beauty. The hard part I was told was doing the R.C. hardware and fitting properly. I think a will join the chair setters in the audience. Remember have fun.

David B

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Thanks David, and welcome aboard. Doing the RC and the running gear will be a first for me, so I'm hoping I can rely on a few more knowledgable folks here to guide me along the way. So far, everything has seemed relatively easy and has gone pretty much according to plan (famous last words). I must say, that the instructions are very good so far, and are enhanced further by cross referencing with Pat Mathews' book.


And I'm definitely having fun! :)

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Construction: Planking

Didn’t have much time for this build this weekend as the other build (Bomb Vessel Cross Section) took up most of the available time, but did manage to fit the bottom planks.

Planking begins with the bottom planking. This is achieved with two large “plastic” sheets. The material is an expanded core PVC called “Sintra”. On the bottom of the hull, there will be no over planking as this gets painted. On the rest of the boat, the Sintra forms an “underplanking”, over which the Mahogany planks are laid. Use of the Sintra simplifies and speeds up the build, and makes the whole vessel lighter (a consideration for later on with the RC version of the build).

I have heard of a number of people having water ingress issues due to the Sintra and the fact that the bottom is also not fibreglassed like the remainder of the boat. I will either seal the hull with a waterproof car body filler, or fiberglass the bottom as well as the rest of the boat – I haven’t yet decided on this aspect.

post-242-0-67090800-1423377640_thumb.jpg Edited by gjdale
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If the Admiral is going take the controls mate I think sheet steel would be better used than plastic :D  :D:P  


Seriously that is a large area to cover and I'm not at all surprised there has been a few problems with it, your right to take the extra precautions mate.


Continue to have fun mate.


Be Good



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  • 2 weeks later...

Once the glue had dried, the bottom planking was faired back level with the chine strip and the transom.




The next step is to release the hull from the build board by removing the previously applied staples in the sheer plank.  It looks kinda boat-like now!






The Sheer plank now needs to be faired to the frames before applying the side planking.  Just debating whether to install some running gear and cabling before installing the side planks.  My order from MACK products arrived during the week, and I’m very pleased with the looks of the various goodies (which will be revealed in due course).


In the meantime, picking up on an idea from the RC Groups forum, I contacted a rubber stamp making company here in Australia and had them make up some Chris-Craft logo rubber pads for the step pads.  The company were excellent to deal with and produced proofs from a photo I sent them.  Once I gave them the go ahead, the finished product was waiting for me when I got home from work the next day.  Can’t beat that for service!  The stamps are only available in grey rubber, but I think they should paint up okay with black paint.  I’m very pleased with the way they have come out.  They look better than the photo suggests – I couldn’t get the camera to focus on the pads instead of the five-cent piece!







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Great start Grant!


My first and only RC model boat, built for my grandson is an Aeronaut 'Diva' (it was cheaper!  :) ). I covered the bottom of the hull with thin aircraft fibreglass and lined every seam inside with epoxy thickened with microballoons  - not the 5 minute epoxy - with a good fillet around where the prop shaft exits the hull. despite quite a few hours in our swimming pool it has stayed completely dry inside. 


Fibreglassing isn't difficult but when you get to it, allow the fibreglass to sit on the hull at room temperature for a day or so and don't use a brush to spread the epoxy, use a thin, preferably rubber spatula. A brush will possibly open up the weave. 


But carry on, I'll be watching.   :)

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Hi Mate,


Those foot pads look really cool, it's a first I think and good that it was a local Ausie company.


Looking at the LOA you have some real nice angles there, their gonna be fun. Good idea to lay some foundation work ready for the radio gear to go in. I you were to put a wiring loom in that would save a headache later and keep it tidy.


Looking forward to further updates mate.


Be Good



Edited by mobbsie
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  • 1 month later...

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