Building a light-weight wooden packing frame

2020-09-23

A lightweight wooden packing frame is both useful and beautiful. I saw the wooden packing frame a friend had made a few decades ago and fell in love with it so much I decided I'd build myself one as well.

To make this frame as light-weight as possible it need to be as strong as possible. Ash wood is normally the strongest wood around where I live (in Sweden). Oak is more resistant to preasure without being dented, but ash has some flex that makes it perfect. It's also a bit lighter than oak. I would suspect elm would work too, but birch, pine, or gruose would be to soft or have short fibres.

Original packing frame
Original wooden packing frame
I derived my packing frame from

Material

I started off with a wide plank of ash wood. It was about 120 cm long and 30 cm wide. I shaved it down to about 3cm (a little more than an inch) in thickness.

Creating and using a glue jig

To make the packing frame as light-weight as possible we create a number of really thin pieces of wood that we glue together in a frame. This produces a really strong material, but include the extra effort of creating a frame to glue the material in.

In the carpentry we happened to have a left-over piece of glulam beam. This made a perfect base for the glue frame.

First we need to draw the intended shape on the piece of glulam beam. Remember to draw the outline of both sides of the material to get correct distance after sawing it.
I drew the outline of the backpack of my friend, but shortened it since I'm a bit shorter than he is. I also made the ribs a bit shorter as well since he said it sometimes got caught up in small trees while skiing in the mountain forests.

Since the glulam beam was wide enough to fit two pieces together I made each piece to glue double the intended width so I could glue two of them at the same time and saw them apart later.
Don't forget to include margin for the sawing blade and some sanding.

So I used the band saw to separate the pieces. I also used the band saw to create thin pieces of my plank. For the vertical parts of the packing frame I went with double width (and saw margin) to glue both at the same time to get them equal, separating them afterwards.

For each piece in the packing frame we glued three thin slices of wood together. To get the thin slices the band saw was used, and the sanding machine to even out the cut surface to some extent.

Glue frame for the vertical pieces
Glue frame for shaping the vertical pieces
Excess glue
Glued

For the ribs of the packing frame a similar purpose-specific jig was created. The horizontal ribs were also made in pair that was sawed to separate halves after the glue had dried.

Glue frame for the horizontal pieces
Glue frame for shaping the horizontal pieces

Since excess glue is bound to be pressed out I might as well mention that after it had dried I carved it away with a regular knife and then pushed the wood through the shaving machine to even out the surface.

Using paper between the frame and the pieces you glue together help releasing them afterwards if excess glue would come in the wrong place. It also saves the frame for ease of re-use.

Excess glue
Excess glue being pushed out

There are different types of wood glue. I intended to use the winter variant since I'm skiing a lot in the winter time, but I had none available at the time so I had to resort to normal wooden glue - hoping the surface treatment will keep any moist away.

Glued pieces parted
Glued pieces parted length-wise, and the material for the last two ribs under them

The same glueing jig is used twice for the rib parts to get four pieces.


Shaping the rib pieces

The material with glued together ash wood is really strong, so let's cut away the excess material. I did this with the band saw and a carving knife.

Layout
Pieces layed out but not yet roughly carved

Mark the position of each rib to the pilars of the frame. The shortest rib goes to the top since the shape of the ribs and the pilars make these bend inwards - making this the shortest distance.

We also have to create taps on the ribs - and corresponding holes in the vertical pilars of the frame. Since the rib pieces are curved this require some tampering before it is a tight enough fit.

For the taps of the ribs I used a thin saw (one of those japanese ones that cuts as you pull rather than push) and a knife.

For the holes in the pilars of the frame I used a hand drill and a few chisels of various widths.

Layout
Pieces layed out
Layout
Pieces layed out
Layout
Pieces layed out
Layout
Pieces layed out

Assembly of the frame

Finally, when happy with the fit - it's time to glue it all together.

The shape

Let's include a few pictures of the shape of the packing frame-

Shape
The shape of the packing frame
Shape
The shape of the packing frame
Shape
The shape of the packing frame
Shape
The shape of the packing frame
Assemble attempt
Assembled before glueing it together

Diagonal support

To make the frame more sturdy parts of the outer vertical parts was cut away and joined into the frame.

Before glueing the frame together, make sure to cut away two thin pieces from the vertical pieces. These will be used as support to strengthen the frame.

Glued
Glued together and drying
(For instructions on how I weaved the basket in the picture, look here, in Swedish though...)

In the picture above the support pieces that was cut away from the vertical parts of the frame are layed out on the drying frame without yet being fastened.

To get preassure for the glueing I used the carpentry workbech and the band of a frame clamp, as can be seen in the picture above.

Top support
Detail of top joints of the support
Bottom support
The bottom support joints

When all pieces were assembled it was time for sanding. First with knife and file, then with sand paper 120, and last with sand paper 240.

Frame shape
The shape of the assambled and sanded frame

Oiling the points

Since linseed oil takes time to harden, and I was planning to be away for a while I heated the oil to about 130 degrees Celsius and placed the bottom points of the packing frame in there for a few dags. This allows for the oil to penetrate deeper into the points of the wood. One can assume the bottom points of the packing frame will be put into damp moss or dirt from time to time, so these are especially important to get proper protection for.

Oiling the points
Soaking the tips of the wood in heated linseed oil

Tying the joints

Ok, the frame probably would have been sturdy enough anyway, but for decoration - to make it look more worked upon - some tying of the joints were introduced.

For this linen thread was used since I wanted it to withstand the linseed oil I was planning to use for moist protection for the wood later on.

There are a few different tying techniques.

Rib join pattern
Cross pattern of middle ribs
Diagonal support joint
Diagonal support joint
Bottom join pattern
Heavier pattern for the bottom joints

Oiling the rest of the frame

For the whole frame, including the thread, heated linseed oil was used.


Finishing off the wood-work

Leather-works

Note the non-leather light-weight piece included for back support.

leatherworks
leatherwork details
leatherworks
leatherwork details
leatherworks
leatherwork details
leatherworks
leatherwork details