The Amazing Hide-A-Deck Travel Cribbage Puzzle Box

I got back into playing cribbage about 18 months ago. Once I was hooked again (about 2 games later), I wanted a fun cribbage board. Off to Google for ideas! 100’s of cribbage boards later (standard, antique, folding, mountain trails, 3d printed, fish, antlers… antlers!?!, the number 29, leather, wood, metal, … you get the idea) and nope, none that I liked. (Yeah, yeah. Picky, picky.) So, taking a break from the cribbage board quest, I read a bunch about secret places to hide things, like false bottom drawers and carved out books! Yup, you guessed it.  For version 1, I made a 4 track cribbage board in the shape of a hardback book (which is an awesome board great for cribbage night at the local brew pub). Alas, hauling that around gets kinda bulky. 

For version 2, I thought, “How about a small cribbage board I could stick in a laptop backpack or bike bag?” This too was great (and I still use it), but it doesn’t want to stay closed in my bike bag! I was stuck. I went off and made a few other things (refrigerator magnets, wooden boxes, saw dust, a figural puzzle, LEGO MOCs, home made hard wood dowels, another figural puzzle, loads more sawdust…). Inspiration struck! I could make SAWDUST! And as a byproduct, I could also make a puzzle box that’s a cribbage board! VERSION 3! And here it is! The Amazing Hide-A-Deck Travel Cribbage Puzzle Box!

Materials

1 - ¼x7x4 inch hardwood board for inner panels

2 - ¼x3x12 inch board for outer panels

1 - 3/8x7x9 inch board for top/bottom

¼ inch dowels or furniture pegs

Black Latex paint for track and numbers

Urethane spar varnish

Tung oil

Titebond 2 wood glue

Planning Tools

Pencil

Paper

Vector design program: Inkscape or CNC program of your choice (Vectric V Carve, Inventables.com Easel!)

Cutting Tools

CNC (or router table) with clamps and scratchboard

Pull saw

Hammer

Utility knife

Belt sander or sanding block

6mm end mill

3mm end mill

60 Degree V bit

150 degree V bit

Combination square

1/8” brad point drill bit

Glue Up tools

Workout band

Spring clamps

F clamps 6 and 12 inch

Paper Towels

Cotton Swabs

Oops fixing tools

Little mitre box Little Miter Box

½ inch chisel

Wood or rubber mallet

Every great cribbage board needs a great design! This travel cribbage board needs to:

1) be self contained for cards and pegs

2) be small to fit in a pack or bike bag

3) have a low radar profile (hey, why not?)

4) use a standard peg layout. 

Let’s go for the radar profile first. Ok, yeah, this is really just me seeing if I could build this all in wood with no magnets, snaps, metal hinges or any other metal to keep it closed. Who doesn’t want a little challenge?

Next, form factor. It needs to hold a deck of cards and the pegs. Easy peasy. Measure the deck (0.70”x2.6”x3.6”) and add some space for the pegs (0.7”x2.6”x0.5”). The inner chamber should to be about 0.75”x2.6”x4.1”. And the rest of the box needs to be made around the cards and pegs with little excess. Oh, and work in the Golden Ratio in this if possible.

And on to the easiest part, the peg holes. EVERYONE knows that a cribbage board has 120 holes per player, right? Or… is it 60? Oh poop. Before the early 1900’s cribbage boards had 60 holes per player. Sometime around WW1, they played more 4 hand cribbage and went to 120. My box is small. In Version 2, stuffing those 240+ holes on top was tight. Tradition! YES! That’s the answer! Each player gets 60 holes and gets to use them twice! HA! Recycle! Yeah, that’s my story and I’m sticking to it!

And geek that I am, I decided to use my CNC, so here are the svg and crv files. For most of my less complex CNC projects, I design in Vectric V Carve, Inventable Easel and Inkscape. 

Designing the Box

There are some wonderful puzzle boxes out there. The one I’m borrowing from is the Modified Japanese Matchbox puzzle(https://diypuzzles.wordpress.com/2015/04/02/japanese-puzzle-box/). This is one of the best write ups for a this puzzle I’ve seen. 

Based on the pocket and a ¼ inch wall thickness and 3/8 inch top and bottom board, the box should be:

Card & Peg Pocket: 2.625"x 4.10"x0.75"

Walls and Top/Bottom: 0.75"x1.275"x0.75"

Total outside dimensions: 3.375"x5.375"x1.5"

A tricky part is the peg hole pattern. It’s got to fit 120 holes in a scoring track that’s easy to work with. I tried denser hole patterns to get the 240 per player, but that was visually tough to work with for the players. I added the chip carve edge and middle panels for visual effect. Blank edges just aren’t fun.

I've added the svg's so you can import to your favorite CAM package or just use them as reference for hand tools. Yes, it can be done an I've done it, but just not for this project. Aaaaaand that's the reason I go the CNC gantry router... oh yeah, and it's way cool doesn't hurt either.

NOTE: So, if you're wondering about depths, the peg holes are 0.23", the track cuts for the side slides are 0.125", the V carve track engraving for the top is 0.05", the panel cuts are half the thickness of the wood (0.125"), the V Carves are limited by the bit and have to be < 0.10", and of course the through cuts are the thickness of the wood + 0.01".

Oh, at this point since we're cutting, I made 3 boards in case I screwed up... I mean, got instantaneously creative with my tools. SO, you'll see 3 different but very similar boards in this instructable. All maple, maple+cherry and maple+walnut.

Since we want to have visible numbering, we need to divide the job into a V Carve for the track and numbers and everything else.

1)     Drill the alignment holes and insert the ¼ inch pegs

2)     Using the 60Degree bit, VCarve the track and numbers

3)     Lightly sand the top of the block

4)     Remove the block from the CNC.

5)     In a well ventilated area, spray the top with Urethane sealant. Spray at least 3 coats.

6)     Allow to dry 24 hours.

7)     Very lightly sand with 600 grit paper

8)     On the track section, use black latex paint and cover the track and numbers.

9)     Using a paper towel, wipe off excess paint.

10) Check for open areas in the painted V Carved paths and repair with more black paint.

11) Allow to dry no less than 2 hours in a warm, dry place.

12) Put the piece back in the CNC using the alignment holes

13) Carve the holes with a 3mm mill bit.

a.     NOTE to go MUCH faster use a 1/8” bradpoint bit to drill the peg holes.

b.     WARNING: I call my 1/8” bradpoint drill bit “Marriage Breaker” as the sound it makes gave my wife and kid immediate headaches. Speed vs Domestic Harmony… Yeah, live and learn.

14) Carve the chip carve regions with a 150 Degree V bit.

15) Using the alignment holes, flip the piece over and finish the carving for the tracks and cutouts.

16) Remove part from the panel using a pull saw, chisel and utility knife.

17) Clean the part up with a utility knife, chisel and sand paper.

18) Sand off any excess paint.

For everything BUT the Top/Bottom panels, it’s a matter of running the G Code files, trimming the parts using chisels (and/or a utility knife), and sanding off the rough edges. So use the steps above, but omit the Urethane Sealant and paint and related steps. . It should go MUCH faster!!!

I LOVE having a perfect project. And I'm sure I MUST have had one in my life, but um. yeah. This isn't it.

Anyhow, I’ve uploaded the corrected design, but on mine, well, I goofed up several times, in particular:

1)     I forgot to chip carve the top/bottom parts until after I’d removed them from the wood panel. Carpet tape and alignment holes do wonders! Look for that ugly panel with the carpet tape that saved the project.

2)     In the fixed wall, I mismeasured the length and it was too long, using the little miter box.

3)     In the long fixed outside wall, the slot for the fixed interior wall was in the wrong place, which was corrected using the miter box and a chisel.

Ok, there are a few others, but I'll leave that for you to find. I sooooooo know where they are.

Do a dry fit to make sure everything does fit. You should then assemble the slides and guides.

For the long slide, the long guide should be well centered left/right and top/bottom.

1)     Apply the glue to the long slide.

2)     Lay the guide holes side up on the glue. Don’t get the glue in the holes.

3)     Clamp one end with a spring clamp. Call it End 1.

4)     Align the guide and the slide on the opposite end (End 2).

5)     Clamp End 2.

6)     Unclamp End 1 and shift the alignment to center.

7)     Reclamp End 1.

8)     Remove any visible glue from tracks and wood with cotton swabs, and damp paper towels. Any remaining glue will stop the slides from moving properly.

9)     Set aside or 24 hours

For the short slide, the short guide should be aligned top/bottom but butted to the end of the slide as shown in the edge on photo. Look for the long, thin tail side (Right in the photo). Use clamping tricks above to align the guide to the slide.

Both slides should dry for 24 hours.

Apply glue to the remaining fixed panels and inner fixed wall to glue the top and bottom together. Insert the slides in as indicated.   Clamp sides and top to keep alignment. I have used exercise bands as clamps successfully.

After the glue dries, remove the clamps and remove the slides.

The action should be smooth, but if it isn't, you can sand off the open edges of the box to thin the box side rails to loosen the fit. If the guide is jamming in the track, sand that off instead.

I am a big fan of food/pet safe materials. So, I use 100% Tung Oil as it is the safest drying oil I could find and you'll notice that I've used only people/pet safe woods. You will need to apply the tung oil once a day for several days in a row to get a thick coating. Allow to air dry.

I heard once that with tung oil, you need to.

Apply it daily for a month, then apply it monthly for a year, then apply it yearly for the rest of it's life.

Meh. You can get some wonderful results without going quite so extreme.