So, I was working an a new cold frame, made out of the old cold frame, which was made out of an old shed.
In the previous post I made a plan, then measured and cut lengths of wood for some new window frames. Now to get out the router. I need to give the window frames an L-shaped cross-section, with a recess for the glass.
The recess was cut deep to accommodate both the glass and a strip of angled edge moulding. The moulding would be nailed into the remaining frame, forming a U-shaped channel that held the glass.
The side pieces can be cut quite easily, as the recess needs to run the entire length of the wood.
The top and bottom strips are a little more tricky, as I need to stop short of the ends and finish the recess off with a chisel.
Here’s where I made a small mistake. On one corner, I was too hasty moving the router after reaching the end, and it nicked the part of the wood that I wanted to retain. I had accidentally cut a channel in the wood where it was supposed to join with the side piece.
My solution was to glue a new piece of wood in place, then shape it to fit. I started with an offcut that was the right shape to fill the hole, though big enough to hold and secure in place. This was glued and clamped and set aside.
Once the glue was dry, I could trim off the excess from this repair using small saws and chisels. Good as new.
A quick check to make sure everything still fits… Very good!
While I had the chisels out, I worked on a way to handle rainwater. I needed channels in the bottom pieces of each frame that would let the water drain without being trapped and forming pools. I marked and chiselled out two funnel shapes in each end of the bottom pieces. With the window frame closed, it would sit at slope, and rainwater would gravitate to this edge and flow out the funnels rather than being trapped.
Next, I began the assembly of the frames. I applied the first coats of wood preserve, and then screwed the edge pieces together. I pre-drilled holes in the end pieces to accommodate screws, then clamped each pair of frame pieces against a set-square to ensure they maintained a right-angle while I secured them together with decking screws.
A quick visual check showed I was building up a good, strong frame with a nice rectangular shape.
The angled edge moulding came next.
I needed to cut most of these pieces at 45 degrees so that they would fit together correctly in the corners of each window frame. Out came my old mitre block (for the last time, it turns out)
This took some careful measuring. The pieces would need to fit nicely together, not too tight but with no gaps. They would expand and contract with changing temperature and humidity, but then, so would the frames themselves, so the fit should be maintained through the seasons.
The cut sections of moulding could be given a thorough soaking with wood preserve, and stained to match the rest of the construction.
Now to build the cold frame’s base and table. I began this by looking at the collection of boards I had assembled in my wood stash. Some time previously I had removed a couple of fitted wardrobes from between two of the bedrooms in the house – this was to make my son’s bedroom much bigger. The wardrobes had shelves in, made from old floorboards, and those boards would be ideal for the base of the cold frame.
I had several long sections, and a few shorter sections. I could sandwich the shorter ones between the longer ones to make a continuous board of a good length. I secured them to strips of wood that I’d run across the boards underneath, to give some lateral strength.
I also needed to think a little about how the box of the cold frame would attach to this base. The depth of the box would be set by the size of the window frames (I’ll come to that calculation later.) Five widths of floorboard would be slightly narrower than the box depth which was a little unfortunate. So I decided to saw off a thin strip from the fifth board, so that the cold frame box would fully straddle the floorboards. I could then secure the bottom of the frame box to the cross-pieces I was using to hold the base together.
Time now to give the base a good coating of wood preserve. I used wood stain on the portion that would stick outside the box and form a table. I decided not to stain the inside of the box though as I felt it would make the box dark and dingy to work in.
Once I had the base and table, I could create some legs. I had already decided to make use of a couple of old fence posts for these. The posts were each 7.5cm square, and about 180cm long. Together with a few strips of wood I could construct some sturdy, 80cm long legs to stand the unit on. After cutting the pieces to size, everything got a good coat of wood preserve.
I secured each pair of legs with strips of wood across the top, and strips a foot or so above the ground level. The top strips would be screwed into the base and table, while the lower strips would be used to hold a shelf.
I had an interesting idea for this shelf. As I mentioned, the legs were made from a pair of old fence posts that had rotted through at their bases. These posts used to hold up a trellis, against which we were growing a fig tree. The trellis was old, but still looked as if much of the wood would be serviceable.
I spent a little while dismantling this trellis, returning it to a collection of wooden strips, then picking through the strips that had the most life left in them. Then I would nail together a new structure from these strips, that would fit under the table between these new table legs. It came out something like this.
Yet more wood preserve, and wood stain would be required of course.
And I had a shelf to sit below the table that could give us somewhere to store plant pots and other garden detritus.
With a few more strips of wood to make up some braces and supports, my legs were complete. I could secure them to the underside of the table and base, and I was ready for the box.
I’ll talk about the box in the next blog post.