Luckily, I have a logan pro frame makers saw which makes easy work of measuring and cutting the frame, but any good mitre saw will work just as well. You could even just cut and butt them together without a mitre.
I guess, I could have attached a frame makers strap (I do have one) to hold my frame until the glue dried. But for some reason I decided to pre-drill holes and after applying wood glue used a screw to tighten the joint and hold in place until set.
I don't think this is a bad method but I would either counter sink them further next time so I could apply more plastic wood or filler or better still use wooden dowels that could be re tapped later to restore tension in the canvas.
My basic frame was more or less complete. But because it was well over a meter in length it needed a middle cross bar to prevent bend when stretching the canvas.
So a cross bar was added and the final step was to sand the sharp edges off so the wooden frame so the canvas would not tear when stretching over the bars.
There are many YouTube videos of how to stretch a canvas so I wont get into masses of detail. The following graphics will hopefully explain things better than my ramblings
After cutting your canvas to size ( allowing enough to get a grip of) Fold and staple middle of one side (1). Jump to the opposite side (2) and stretch until tight and staple. Do the same on the ends (3, 4)
Start again from your first staple and stretching out and away from the middle staple both sides as in (5) follow the same procedure as previously and keep working your way around.
Continue until all sides are stretched, stapled and your corners trimmed and neatly folded and secured. Again YouTube can help with how to fold corners. You should now have a taut canvas ready for priming.
I actually had a pair of stretcher pliers handy but found my hands were sufficient for stretching, but it was a low grade un-primed cotton so may be a different story with stiffer ready primed rolls.
I also managed to tear the first canvas by trying to stretch too much so be aware of that
The weave of the cotton was so loose after stretching that the primer literally soaked through, so it took several coats of gesso primer to get a good finish, I even applied it with a pallet knife on some difficult areas. I had to purchase more gesso so any savings I thought I might make were lost.
Traditionally, you would size a new canvas for oil paints with rabbit skin glue prior to priming and that may have at least sealed the weave better and helped with the gesso above.But from what I could glean from online searches it could also cause your nice tight canvas to sag, and as I did not have wedges to tap in and restore tightness (those wooden dowels would have helped ?) I opted for the modern way using acrylic gesso which is suitable for oils and acrylics as well.
I have since learned that the opposite may be the case and rabbit skin glue tightens the canvas. However I cannot verify that for sure.
I also sanded the canvas down between coats to remove any rough areas or odd bits of stiff weave . In the end my canvas was finished and looking pretty good. My worries of the canvas sagging was not realised, so all that was required next was a final coat of oil primer to help the oil paint from sinking in and dulling.
This also improved how the oils flowed on the canvas, I had deliberately left an area of just acrylic gesso to test the difference and it was markedly noticeable. Good lesson learned here.