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Dec 31, 2013, 08:48 AM
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Mini-Review

Dumas 1938 Chris-Craft 16' Painted Racer


I receive a fair amount of mail inquiring as to which Dumas Chris-Craft kit is best for a rank beginner, including a few from experienced modelers who are new to boat building.

Having built just about all of the CC kits from Dumas over the years, the later offerings are a good bit easier to build then some of the earlier stuff. However, in every case, mahogany planking is required, which is without a doubt the toughest part of the process -- and then comes finishing. Untill now, I would have looked upon the 19' Racing Runabout as the best place to start -- for a mahogany boat -- do to its simple straight clean lines.

But for those who want to get there feet wet and learn to build boats without the complexity of the mohogany planking and finishing, the guys at Dumas have come up with a terrific place to start -- the 1938 Chris-Craft 16' Painted Racer.

The basic design is typical "late model Dumas" and features all wood construction. The frames are both dye and laser cut from lite ply -- NOT the old mahogany luan that we all learned to hate over the years. Planking is primarily balsa - more on that as we get into the build - which make this one the absolutely easiest Chris Craft I've built yet. And that being the case, for a first time CC builder, the Painted Racer will be a great place to start.

Let's get building. . . . .
Last edited by P. Tritle; Jan 28, 2014 at 07:04 AM.
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Dec 31, 2013, 08:55 AM
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Dec 31, 2013, 09:01 AM
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Getting Started on the Build


As with any build, I always recomend studying and reviewing the plans, detail drawings and building instructions thoroughly before gluing anything together. Becoming familiar with the entire assembly process before getting underway can eliminate a bit of confusion as things progress through otherwise uncharted territory.

To begin, I used the Parts ID drawings in the instruction book to mark the part numbers on each of the parts before any of the parts were removed from their sheets. And with that, the only thing left to do is get started.

Construction begins with the display stand. The stand is made from a sheet of PVC plastic with the stanchions cut and shaped from wood dowel. I left about 1/16" of dowel protruding through the bottom of the stand, and will glue a cork non-skid pad to the bottom of the legs so's not to scratch the display shelving.
Dec 31, 2013, 09:03 AM
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Assembling the Frames


The frames are built up per the instructions. Detail drawings are also provided to clarify the location of the floor supports and steering column support.
Dec 31, 2013, 09:11 AM
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Building the Keel and Deck Sheer


The forward keel is laminated from 2 lite ply parts. I used carpenters glue and clamped the assembly for 20 minutes or so while assembling the deck sheer. The deck sheer was glued together using medium Cya. After the parts were glued, the seams were sanded, the with the sanding dust still in the joint, thin Cya was dribbled into the dust and sanded again. The process was repeated until the slots were level and flush with the surface. Using the sanding dust and thin Cya makes for a very strong joint with no drying time required.
Dec 31, 2013, 09:20 AM
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Setting Up the Basic Hull Frame


Assembly begins with pinning the Deck Sheer to the building board, then marking the location of each frame per the instruction manual and the isometric detail drawings also provided. The frames are then glued in place using a Jig provided to insure they go in at the proper angle. From there, the forward keel section is glued in place, followed by the hardwood chines and strigers aft.

Once all the parts are assembled and the glue is dry, the frame is sanded to contour on the bottom in preperation for the bottom planking.
Dec 31, 2013, 09:28 AM
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Planking the Hull Bottom


To keep things simple, the hull is planks longitudinaly from Frame 3 aft, and perpendicular to the keel forward of Frame 3. While the frame is still pinned to the board, the aft planking is done first beginning at the center and working outward. I like to add the planks one each left and right rather then doing one side first and then the other -- it keeps the loads more symmetrical as the process progresses eliminating any possibility of warping when the hull is removed from the board.

Then once the aft planking is in place and trimmed up to the chine the forward planking is added, again working side to side progressing forward till all of the planks are in place. And finally, the edges are roughed in using a sanding block
Dec 31, 2013, 09:33 AM
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Getting the Hull Ready for the Side Planking


The hull frame is removed from the building board and the frames and deck sheer sanded into contour. The stern sub-structure is set up and sanded to contour as well. At this point the hul is ready to add the side planking.
Dec 31, 2013, 09:40 AM
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Planking the Hull Sides


The sides are planked fill length beginning with the bottom. The first plank is 1/8 X 1/4 bass wood, and is the only hardwood plank used in the process. The curve is gentle, so there's no problem getting the plank to conform to the curve, and having a hardwood plank on the sharp edge will go a long way in preventing dents and dings from deforming the chine.

From there, the balsa planks are added one at a time until the process is completed. Again I worked from side-to-side to prevent any chance of warping the hull. I might also mention that to glue the planks in place, Carpenters glue was used along the edge of the planks with medium Cya used to attach the plank to the hull frame. Small pins were used to hold the edges in alignment whill the glue dried.

Then once dry, the edges were trimmed and the hull rough sanded to shape.
Dec 31, 2013, 09:48 AM
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Finishing the Planking


After the glue had dried the hull was finish sanded to basically level up the surface. Then a thin coat of the boat Builders Secret Weapon, Drywall Mud (alias Wall Board Joint Compound) was squeegeed over the entire hull to fill the voids and low spots and provide a smooth even surface. A couple of applications are typically needed to build up the surface and fill all of the bad spots in preperation for fiberglass.

Then the inside is sealed up using a heavy coat of thinned resin. I thin the West Systems Epoxy with just enough Denatured Alcohol to make it soak into the wood, but not so much that there's no build-up with just one coat. Once you get it down, the wood will be sealed nicely and any small gaps will be filled to prevent water intrusion should the inside get wet.
Dec 31, 2013, 09:58 AM
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Laying Out the Deck Structure


The Deck Formers are located and glued in place followed by the bass wood fore deck centerline stringer.

Then once the deck formers are all in, the mahogany planking is added in the cockpit. Finally, the rear hatch assembly is layed out and assembled directly in the opening to insure a good fit. Once the basic structure in done it's removed, sectione, and sanded to shape.

And with all that done, the top side is pretty well complete and ready for planking.
Dec 31, 2013, 10:03 AM
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Planking the Deck


The fore deck is sheeted using the dye cut lite ply sections. The afte deck is planked with balsa. The forward and rear hatches are also strip planked with balsa, but I see no reason why the aft deck couldn't be sheeted with 1/8 balsa should you prefer that to strip planking. Either way will work.

Then with all the planking in place, the edges are trimmed and sanded into the hull sides and the top surface block sanded to shape. Then a thin coat of drywall mud was applied to fill the gaps and low spots.
Dec 31, 2013, 10:09 AM
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Fiberglassing the Hull


At this point the entire hull was given a good detail sanding in preperation for the fiberglass. The hull was covered with 2 oz. cloth in 5 sections - top, bottom, sides, & transome -- and sealed with a coat of thinned West Systems resin. Once cured, the edges were trimmed and the entire hull lightly wet sanded and a second coat of thinned resin applied.

At this point, the hull is done and ready for final surface prep and prime. More on that as things progress.

PAT
Last edited by P. Tritle; Jan 28, 2014 at 07:07 AM.
Dec 31, 2013, 02:32 PM
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Build


Mr P.Tritle,in block(entry13)are you thinning the West Systems with Denatured alcohol when fiberglassing like when you sealed interior of the hull with thinned West Systems and Denatured alcohol?
Dec 31, 2013, 02:38 PM
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Quote:
Originally Posted by californiakid
Mr P.Tritle,in block(entry13)are you thinning the West Systems with Denatured alcohol when fiberglassing like when you sealed interior of the hull with thinned West Systems and Denatured alcohol?
cal, Yes, I use West Systems thinned with Denatured Alcohol for all of the sealing and fiberglassing. I will also use West Systems thickened with either Micro Balloons or Chopped Glass filler in the high stress areas like the fillets around the prop shaft and rudder bearing tubes.

PAT


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