Dumas PT-212 User manual

PT-212 1Kit No. 1257
PT-212
Kit No. 1257
INTRODUCTION
THIS IS A TOY! Modeling should be fun, so don’t sweat the small stuff. Enjoy the
experience. This kit is fun to build as is, and at the same time, gives you, the builder, and those of
you who like to tinker, the foundation to let your imagination to go hog wild. Just remember one
very important thing, there are NO model police, this is just a toy.
Before you start any construction, please read the entire instruction booklet to acquaint
yourself with the building sequence of this kit.
We who have designed the kit and have written the instructions have tried to make all of
the contents as accurate and correct as possible. Drawings and text have been thoroughly
checked and crosschecked. However, due to the variability of material, personal skills, and so on,
neither the designer, nor Dumas Products Inc., assumes any responsibility for any damages or
other losses incurred that have resulted from misuse of the material presented here. All
instructions and drawings should be carefully studied and clearly understood before beginning this
project.
Experienced modelers can jump into building this model and use whatever construction
sequence and materials that appeal to them. The less experienced modelers would do better to
follow the steps in the numbered sequence. The model was designed to make its building as
foolproof as possible. However, I recognize that nothing is proof against a really determined fool.
When a more detailed explanation is needed to clarify a particular building operation, a
detailed drawing is included indicated by a figure number. This drawing can then be found on the
larger sheet (11 x 17), which will be easier to see and read.
Also enclosed is the Parts List. Please do a complete inventory of the kit and contact us
at 1-800-458-2828 if anything is missing. To process your order more efficiently, please have the
PART NAME AND NUMBER ready when you call.

PT-212 2Kit No. 1257
DIE-CUT PARTS LOCATOR SHEET

PT-212 3Kit No. 1257
LASER PARTS LOCATOR SHEET

PT-212 4Kit No. 1257
TOOLS & MATERIALS NEEDED
Here is a list of additional tools you will need to construct your DUMAS PT-212 kit.

X-acto knife (No. 11 and No. 16 blades)

Ruler

Medium CA glue and Accelerator

Sandpaper - Course (60-80 grit), Medium (100-120 grit), Fine (220-320 grit)

Paint Brush - 1/4”, 1"

Clamps

File -1/4” dia.

24" long Straight-edge

Polyester Body Filler (Bondo)

Soldering Iron

Epoxy

Solder

3/4” wide Masking Tape

Drill bit set: (1/32” dia. (No 67) through 1/4” dia.)

White Lithium Grease

Buckshot (No. 4 (.240 dia.)) (no more than 2 pounds)
DECAL
The decals supplied in the kit are pressure sensitive mylar. DO NOT soak them
in water to remove the paper-backing sheet. Simply cut around each decal with
a sharp x-acto knife, then peel away the paper backing. See the full size drawing for the proper
placement. Trim your decals close to the design edges as you can to minimize the clear halos.
PLASTIC
All of the plastic vacuum form parts were pulled from .040 ABS sheet. Since the heated
plastic is pulled over a form, some stretching may occur which will thin out the plastic. This is why
the lifeboat hull thickness, for example, may end up being only .020 thick. When cutting out the
vacuum form parts, do not attempt to cut through on the first pass. We have found that a utility
knife or a single edge blade works best. In some cases, you will cut through on the first pass, but
scribe lightly for better control. The vacuum form parts will take at least two passes to scribe a
deep enough cut. If the knife doesn’t cut through, then you can wiggle the excess plastic back and
forth until it snaps off. Located towards the back of the Instruction Booklet is the vacuum Form
parts Locator sheet. Use these sheets to identify the required part.

PT-212 5Kit No. 1257
GLUE AND ADHESIVES
CA (Cyanoacrylate): This is for general-purpose construction when gluing wood to wood,
metal to plastic, or wood to plastic. It is the ONLY glue to use when attaching the Expanded PVC to either wood
or to itself. We recommend using gap-filling (medium) CA cement. When using the gap-filling (Medium) CA,
hold the parts together at least 15 seconds. Use with caution since it will bond skin instantly to your work in
progress.
CA Accelerator: This is sometimes used along with the CA adhesives to “kick off” the CA
cement. Generally, if your CA is fresh, you won’t need it too much unless you are in a hurry, but if the cement
has gotten old, then the accelerator is almost mandatory.
Epoxy: This is sometimes used as a substitute for the CA adhesives. Generally, use epoxy to
build the basic wooden frame, and when attaching the deck fittings. DO NOT USE EPOXY ON YOUR PT-212.
Liquid Plastic Cement: This is used to cement styrene plastic-to-styrene plastic. It will
not work with the Expanded PVC.
PAINTING
There is an old adage in the Navy that warns recruits to salute everything they see, if it
doesn’t return your salute, paint it gray! Well, just about everything on the PT boat is painted gray.
Even the horizontal surfaces are painted gray. To eliminate fish eyes, oils, and dirt, wipe parts with
rubbing alcohol on a clean rag before spray painting.
Painting Tip: I painted all of the major assemblies separate before they were glued to the
deck to get into the hard to reach places. After the major assemblies were cemented to the deck,
then I painted the deck/hull. This way, I was guaranteed a good gluing surface between the deck
and the part. The smaller parts like the Hatches, Vents, and Fuel Caps were all cemented to the
Deck first, then painted. Suggested colors are listed below:
Testors Model Master (Spray or Bottle)
AGGRESSOR GRAY
FS 36251
Hull above water line, Cabin, Life Raft, Masts, Bitts,
Railings, and all small details
Testors Enamel (Spray)
FLAT GRAY PRIMER
1237
Enamel undercoat
FLAT RED
1250
Hull below water line, Rudder
Testors Enamel (Bottle)
SILVER
1146
Lights
FLAT BROWN
1166
Wheel

PT-212 6Kit No. 1257
WATERLINE (See the FULL SIZE drawing)
Laying out the waterline is simple and easy to do. Just follow these steps when you need to, to
ensure a straight waterline. “Boot topping” is sometimes used to refer to the waterline. Actually, the “Boot
Topping” is just a band of color to represent the waterline. The Term “Waterline” is used to mathematically
represent the displacement of a given vessel.
A Look at the side view on the FULL SIZE DRAWING. Note the dimensions given in regards to the waterline: 3-
1/2” at the bow, and at the transom, 1”. The 3-1/2” dimension is taken from the BOTTOM of the overhang.
A 1/32” difference here and there is no big deal…it’s just a toy.
B Now that you have the previously ascertained marks on the hull, place your boat model on the stand or blocks
of foam on a flat surface like a table. Then slide the stand or blocks back and forth until the mark at the bow
and the mark at the stern are an equal distance from the top of the table. Some fudging may be necessary to
get it just right. You may need to place a level on top of the boat, crosswise, to make sure that the boat is level
side to side. Place a weight inside the boat model to anchor it down so that is doesn’t move.
C Tape a sharp pencil to a block of wood so that the pencil is the same height as the mark at the bow.
D Run a pencil around both sides of the hull. You might need to go over it a couple of times until you can see your
line. If you don’t want to use pencil, you can also use a scribe to scribe a line, but if you use a scribe, scribe
lightly because if you make a mistake, oh well…
FULL SIZE DRAWING
The drawing provided (24” x 36”) was drawn full size. You can measure directly off of the
drawing. Some stretching or reducing of the drawing may have happened during the copying
process, so beware. When determining a particular dimension, you can always round over to the
nearest 1/32” because you don’t have to be exact. Remember, it’s just a toy.
PARTS IDENTIFICATION
Located in the front and back of this instruction booklet is a PARTS LOCATOR sheet.
Use this sheet to identify the parts as you are building the model. Label the parts with a pencil
before you remove them from the sheet. Failure to do so will create confusion since some of the
parts look the same. The PARTS LOCATOR SHEET is different than the MATERIAL LIST. The
Parts Locator is a picture of the different parts, while the Material List is everything supplied in the
kit.

PT-212 7Kit No. 1257
NOTE: Before you begin construction of this model, check to make sure you have the
entire set of 11” x 17” Figure Drawings, (Figures 1 –87), AND the full size drawing on the
24” x 36” sheet of paper. If you do not have these items, the building of this kit will be
very frustrating. If you are missing these drawings, call 1-800-458-2828 to receive your
copy.
MARKING THE PARTS (See FIG. 1)
1 You will find the Parts Locator on the first page of the Figure Sheet - FIG. 1. You will also find them
at the beginning of the Instruction Book, if you haven’t noticed already, and at the end of this
Instruction Book. Some people just don’t like to read my instruction books anymore, so I have
placed them at the most popular viewing areas for your convenience, so there is no excuse.
2 Mark the parts, using the Parts Locator as a guide, with a soft No. 2 pencil.
NOTE: DO NOT punch out any of the parts until they are needed.
BUILDING THE STAND (See FIG. 2)
The stand provided is used primarily to stabilize the model during construction. If you were
careful with the construction, then this stand can be used to display your boat. That’s up to you.
You will using the four (4) strips of 1/8” x 3/8” x 36” basswood for the
stand, floating somewhere in the kit box.
You will also find the full size patterns on the last 11” x 17” sheet. (Go look
for FIG. 87)
3 Lay a sheet of wax paper over the two frame patterns. This will prevent the parts from sticking to
the drawing.
4 Cut the individual lengths of 1/8” x 3/8” basswood to match the full size pattern.
BUILDING TIP: As you have probably figured out already, each Frame is broken down into three different
segments: the two outer structures and the inner support. This is how I achieved the construction
of each Frame. I first cut and cemented together one outer structure, pinning it down on to my
building board. Then I added the inner supports while the first structure was still pinned down.
(oversized a little, then sanded down later on) These parts were pinned in place as well. Finally, I
cut and glued the remaining structure on top, pinning these parts down as well. I then let this whole
assembly dry for an hour or so. (I used Titebond glue) After one Frame was finished, I moved over
to the other Frame. The total time it took me to build both Frames was about 1-1/2 hours.
5 Cut two runners 12” long, and four runners 11-1/4” long.
6 Cement the two long runners to the outside ends of each Frame, then cement the four short
runners to the inside to add additional support to the two Frames.
7 Paint or stain the Stand to taste.

PT-212 8Kit No. 1257
CUTTING OUT THE HULL (See FIG. 3)
8 Lay the hull down, flat on your workbench, so that you are looking at the OUTSIDE of the hull. Cut
out the vacuum form hull along the bottom edge of the Sheer on the OUTSIDE of the hull. Go look
at the “SECTION THROUGH HULL” drawing if you are confused. You can use a sharp hobby knife
for this procedure if you want to.
NOTE: The hull was vacuum formed with a big fat wide (1”) flange all around the base of the mold.
This is there to help stretch the plastic sheet while heat forming. THIS IS NOT PART OF THE
HULL.
NOTE: It is highly recommended that you use a utility knife to cut out the hull since the styrene
plastic is a rather thick (.060), don’t try and cut all the way through the first time.
BUILDING THE DECK (See FIG. 4)
9 Lay a sheet of wax paper (about 32” long) over your Building Board.
10 Cement the two Deck halves (D1) together. Use gap-filling (medium) CA glue for this procedure.
NOTE: Lay the Deck on the wax paper as the glue dries to prevent the Deck from sticking to your
building board.
NOTE: You may want to lay weights on top of the Deck after you cement it together to keep it flat.
11 REMOVE THE WAX PAPER FROM THE BOTTOM OF THE DECK.
12 Draw a line, 1/4” away all around the edge of the opening in the Deck. (See FIG. 5)
13 Cut and cement 3mm x 1/2" PVC strips to frame the opening in the Deck. (See FIG. 6)
NOTE: The PVC strips will run on the INSIDE of the pencil line, so that, as seen from the top, you will
have a 1/4" face of the strip showing on the outside of the opening. This will act as a lip for
the Deck Hatch to sit on.
14 Place the Deck back on your building board so that the PVC frame is facing up. Staple the Deck to
your building board at the four places shown on the drawing. You don’t need the wax paper any
more. (See FIG. 7)
NOTE: Don’t go hog wild with the staple gun. You only need four staples.
NOTE: Make sure that the two front staples line up with the PVC frame.
15 Lift the front nose of the Deck up, then slide a 1/4” block of wood (about an 1” long) underneath the
nose of the Deck.
NOTE: The block of wood only needs to slide in about 1/4”. So, don’t over do it.
16 Laminate and cement together two K2’s. (See FIG. 8) Use gap-filling (medium) CA glue for this
procedure.
17 Cement the two K1’s to D1. The rear corner of each K1 must be 3/16” away from the rear edge of
D1. (See FIG. 8) Use gap-filling (medium) CA glue for this procedure.
NOTE: Each K1 will run along the side of the 3mm x 1/2" PVC strip.
18 Cement the K2’s to D1. Use gap-filling (medium) CA glue for this procedure.
NOTE: The rear corner of K2 will touch the front 3mm x 1/2" PVC strip.
19 REMOVE THE DECK ASSEMBLY FROM YOUR BUILDING BOARD.

PT-212 9Kit No. 1257
CEMENTING THE DECK TO THE HULL (See FIG. 9)
20 Lightly sand the inside ledge of the plastic hull using 100-grit sandpaper. Basically, if you just
remove the gloss from the plastic, you will be just fine.
NOTE: This will provide a “tooth” for the cement.
21 Test fit the Deck assembly into the Hull. Some sanding may be required. Sand as needed.
NOTE: You will need to round over the two rear corners of the deck so that it fits inside the hull.
22 Run a bead of gap-filling CA glue along the entire ledge of the hull, then cement the Deck assembly
to the Hull.
BUILDING TIP: You can hold it down for a few seconds with your hands, but I also used masking tape to
hold it together, especially towards the center. I pushed down mainly at the bow (the pointy end)
and at the stern (the square end).
23 Run another bead of gap-filling (medium) CA glue along the entire edge of the deck for added
insurance. Let dry.
24 Sand or plane the excess plastic down even with the Deck. (See FIG. 10)
BUILDING TIP: I used a block plane for most of this procedure. It cuts down the excess plastic quickly, then
I switched over to my sanding block with 100-grit sandpaper to finish it off.
25 Fill in the seams with Bondo, or putty to clean up the Deck, and make it look nice.
FINISHING UP THE HULL
26 CHINE STRIP: Cement a strip of .06 x 1/8” styrene along the Chine, on both sides of the hull. You
will be using two strips for each side. (See FIG. 11)
NOTE: Begin each strip, 3/4" from the bow (the pointed end).
BUILDING TIP: Since the .06 x 1/8” styrene strips are 14” long. All you really need to do is to start gluing
the first strip at the transom, (the rear of the hull), then glue on the second strip. If you did
everything right to begin with, then the end of the second strip should end up exactly where it
needs to be. What I’m getting at here is that you don’t need to measure that 3/4” measurement at
the bow. Remember, it’s just a toy.
27 MUFFLERS: Cut out the vacuum form Mufflers from the carrier sheet along the INSIDE of each
Muffler. Notice that there is a left and right set.
28 Sand the back of each Muffler to remove any edge, and to make sure that the back of the Muffler is
flat.
29 Cement the Mufflers to the sides of the hull, adjacent to the Chine Strip, following the dimensions
shown on the drawing. Use gap-filling (medium) CA glue for this procedure. (See FIG. 12)

PT-212 10 Kit No. 1257
INSTALLING THE SHAFT/STUFFING BOX (See FIG. 16 & 17)
For now, all you will be installing is the Stuffing Box and the Rudder Block/Tube. If you do
this now, then all of the hull construction will be done. If you skip over these next two steps, then
you can always go back, but it’s so much easier to do it now, and get it out of the way so that you
can paint the hull without any problems. You will be finishing the rest of the Running Hardware
installation later on AFTER you have completed all of the deck details.
NOTE: Don’t worry about the numbering sequences of the figure numbers. Just follow the
directions as written, and everything will work out at the end. I just found it easier to install
some of the running hardware now, than to wait until all of the pretty detail was on the deck
to get in the way.
30 Turn the hull over, you are now looking at the bottom of the boat.
31 Measure forward from the edge of the Transom, on the OUTSIDE 6”, then cut a slot 7/32” x 1-1/4”.
(See FIG. 16)
BUILDING TIP: (See FIG. 17) To cut the slot, first drill two 7/32” dia. holes at the dimensions given
above. Then with a utility knife, remove the center section of material. The plastic is soft enough to cut
through, you can cut it by hand without any power tools.
32 Measure forward from the edge of the Transom, on the OUTSIDE 2-1/16”, then cement the Skeg
(K3) to the bottom of the hull down the center. Make sure it is centered inside the hull. (See FIG.
19)
NOTE: The Skeg may not touch the slot opening because you will need to file the slot later.
33 Take a round file (at least 1/4” dia.) and file the slot opening at both ends so that the Stuffing Box
(3/16” dia. x 6-1/4” brass tube) will lay flat on the Skeg.
34 Locate the supplied 3/16” dia. x 6-1/4” long brass tube. We will refer to this brass tube as the
“Stuffing Box”.
35 Cement the Stuffing Box (3/16” dia. x 6-1/4” brass tube) to the hull and Skeg. The Stuffing Box
must extend 1/16” out from the rear edge of the Skeg, and centered on the Skeg.
36 Seal the area inside and outside of the hull around the Stuffing Box with a blob of Bondo.