Small Projects #9: Purpleheart Burial Flag Box

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Blog entry by Madmark2 posted 01-28-2020 12:28 AM 546 reads 1 time favorited 5 comments Add to Favorites Watch
« Part 8: Jatoba and Marble Plant Stand Part 9 of Small Projects series Part 10: Lathe practice - Dog bone »

A veteran friend of mine, Bert, recently passed and I’m making a flag box for his burial flag out of purpleheart. While appearing simple to make, computing the dimensions from just the 17-1/2” side of the folded flag is a challenge. You have to take into account the diagonal lengths (the length of a 45° miter on 3/4” stock is 1-1/16”)

The neat thing is that the three pieces:

Pieces mitered, rabbeted and grooved.

When stood together the pieces hold their form on their own.

No fasteners or glue.

Waiting on the lexan for the front. Will update when completed.

-- The hump with the stump and the pump!

5 comments so far

View LittleBlackDuck's profile


6979 posts in 1882 days

#1 posted 01-28-2020 03:36 AM

Have you had any exposure to SketchUp (though there are probably many others out there that I haven’t tried or familiar with)?

Using SketchUp, you can draw internal dimensions and when the outsides are sketched in you can measure appropriate sides to get an exact length… Then you get a chance to stuff up those exact measurements when you start cutting!

-- If your first cut is too short... Take the second cut from the longer end... LBD

View Madmark2's profile


2539 posts in 1650 days

#2 posted 01-28-2020 05:08 AM

I have AutoCAD but the machine is down. I’m one of those guys that wants to know why the dimension is what it is and not just take the drawing software’s word for it. Figuring it old school with just a four banger calculator with pencil and paper. The design I use is all 45° angles, not the 22.5°/45° version.

The length of the sides are the inside dimension, plus two miters (stock thickness), and a bevel (stock thickness times the square root of two: ~1.41). To figure the cut lengths you need to know the folded flag short side (17-1/2”) and the stock thickness (3/4”). The two sides are therefore 17-1/2 + 3/4 + 3/4 + 1-1/16 or 20-1/16”.

The bottom inside dimension is the square root of twice the square of flag short side. The overall length is that plus two miters. This is sqr( 2×17.5^2) + 3/4 + 3/4 or 26-1/4”.

The final width is the bottom plus two bevels: 26-1/4 + 1-1/16 + 1-1/16 or 28-3/8”. I’ll leave figuring out the final height as an exercise for the reader. (Hint: perpendicular bisector)

Both ends on all three pieces are mitered at 45°.

The front is slotted 1/8” w x 1/4” deep, 1/4” back from the front edge for the lexan ‘glass’.

The back is rabbeted 1/4” square on the TS for the plywood back. To make the rabbet I set the fence so the distance to the outside of the blade and the blade height are both 1/4”. This way I can run the face, flip the board, run the edge, and have a perfect square rabbet.

CAUTION: on the 2nd rabbet cut the ~1/8” sq cutoff WILL be ejected towards the operator.


This is not an unsafe practice as the stock ejection is a planned part of the operation and not an accidental kickback.

Cut precisely all the joints close and it free stands on it’s own. Just think how stable it will be when it’s actually glued together.

Ans: the height is exactly half the base overall width or 14-3/16”

-- The hump with the stump and the pump!

View jeffswildwood's profile


4878 posts in 3039 days

#3 posted 01-28-2020 01:32 PM

Nice job. I have made several flag displays over the years. One thing I noticed is flags have different dimensions when folded depending on who folded it (tight or loose). The way it is folded can affect size. I have had to refold several to get it tight then adjust the measurements to fit nicely. I too used the 45 degree angle for assembly. It works nicely. Another style I use is to extend the base and have the risers sit on top of the base using screws on the bottom to hold it together.

-- We all make mistakes, the trick is to fix it in a way that says "I meant to do that".

View Madmark2's profile


2539 posts in 1650 days

#4 posted 02-18-2020 07:24 PM

Finally finished the box. Had to special order both the lexan and birch 1/4” ply for the back. I had glass clips in stock along with the felt feet.

Front View

Measuring, marking and cutting the lexan was unexpectedly complicated. I needed an 18-1/8” triangle out of an 18”x24” panel – a neat trick I must say. I tried setting up my miter gauge but the gauge was out of the miter slot before the workpiece hit the blade. Being a 45° cut the rip fence was useless. I had to mark the line and free hand the piece – NOT a practice I recommend.

Rear View

Tell me, anyone got any better ideas than freehand? And don’t say a sled for two cuts. Anyway the sled for an 18”x24” or 24”x24” piece on a 45° diagonal would be the size of a half sheet of ply and cost more in time and materials than the project itself! LOL

I had forgotten just what a PITA these are to clamp. I just went merrily along assuming my band clamp would do the trick, alas no. The band clamp seemed to work on the dry fit but when it came to the glue up everything squirmed and the lexan kept slipping out of the slot. Very frustrating and so I had to reset and try again.

I used a pair of corner clamps and glued the sides at the spec. Once that had dried I tried gluing the base in and again failed with the band clamp. I had to resort to a run joint held by hand for a few minutes and then left to set. This morning it seems to have set.

I predrilled the screws for the clips that hold the back on and drive them by hand after waxing the holes, after all purpleheart is a hard hardwood.

Two coats of Johnson’s paste wax lightly buffed for finish and six felt feet so the whole thing is non-marring.

The bottom and back were both stamped with my initials and dated. I expect Bert’s widow to get a small brass plaque engraved for the front and center of the base.

Bottom stamps are hard to read

Back stamps are easy

I figure I’ve got about $75 just in materials in it. If I weren’t donating it I’d put a $150 price tag on it

$35-40 2-1/4 bf purpleheart
$22 18×24 lexan
$7 24×24 poplar ply

-- The hump with the stump and the pump!

View John Stegall's profile

John Stegall

549 posts in 4578 days

#5 posted 04-25-2020 01:40 AM

I realize it has been a couple of months, but this is the perfect discussion as I have to make two of these. One for a relative and one for a very good friend. Thanks for the added info.

-- jstegall

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