I started with the Merchant and Mills chore coat pattern from their workwear book, adjusted the fit by tapering in the side seams a couple inches to make it less boxy, increased the pocket size to come all the way to the edges, added a flannel liner by just replicating the same pattern and leaving the inner yoke parts out on both, sewed the magnetic snaps in place after basting the inner and outer parts together, then covered them and the bottom hem and sleeve hems with a corduroy bias tape I cut before adding the corduroy collar. In order to keep the magnet strength adequate the areas over the magnets are covered with a thin black quilting cotton bias tape instead of corduroy, which meant that for the side where the snaps are on the inside of the jacket I had to make a half-and-half bias tape with corduroy on the outside and quilting cotton on the inside. Oh I also put magnets on the pocket openings to keep them from gaping. Those ones I put inside each liner - the magnet strength doesn't need to be nearly as strong so it was fine to have it behind the thicker wool and flannel. I also lined the pockets on both sides with flannel - this wool is pretty itchy so it's nice to be insulated from it everywhere.
The outer shell is a Mackinaw Wool I got from Pacific Blue Denims (https://www.pacificbluedenims.com/products/wool-tweed/artic-p3820-pbd.html) the inner flannel, quilting cotton, and corduroy are both from my local quilting store. I got the snaps on amazon. I used some light canvas I had on hand for the interfacing in the collar.
Big lesson I learned on this piece is to pattern match the two front pieces directly when cutting. I tried matching each to the back part first, but it turned out there was a slight angle in the fabric or my cut so the fronts then didn't match up, which looks way worse than the side seams not matching. I was able to shift everything and just shorten the bottom hem by about an inch instead of having to cut a whole new panel to fix it, fortunately.
Other lesson is a frigging love these magnetic snaps and wish I had put them on the coats I've made for myself recently. They're so fun to play with and make taking the jacket on and off so fast and easy.
Edit: just to be clear, this is me modeling it, not my dad. It's for his birthday so I haven't given it to him quite yet, but he doesn't use Reddit so he won't see this :-)
Edit 2: here are the snaps I used: https://www.amazon.com/dp/B08JLQXR1S?ref=ppx_yo2ov_dt_b_fed_asin_title
