Monday, December 3, 2007

Miter, Miter, Toil and Trouble!

I want to start by apologizing for not getting anything posted in the past 2 weeks. It is the Holiday Season and we've been very busy with preparations for Christmas. I volunteered to join the choir at our church for the Christmas Party, which was held on December 8. Everyone had a good time & none of the glassware broke, so I guess we did OK.

In addition to all of the preparations, things have been hectic at work. My manager is taking off the last two weeks of the year; Friday was his last day. We had a lot of work to get done before he left. When I got home in the evening, I just had too much to do. This coming week will be no exception -- I still have to go shopping for Mary's gifts, and the evenings this week will be spent with our traditional cookie baking. But now, I can bring everyone up to date.

When last we met, I had finished making the base board with the fair curve arch. Next, I mitered it & cut it to finish length, along with the miters for the pieces that wrap the sides. It's not just that simple, though. I want the center of the arch to be at the center of the cabinet, so you just cut the board anywhere.

The process starts by measuring the front of the cabinet. The photo above shows me making that measurement. It came out to be 25 1/4". That makes the midpoint 12 5/8". So I measured 12 5/8" from one end & made a mark, as shown in the photo below. The picture shows the base board on the bottom of the base cabinet -- that horizontal dark line is the base board's shadow. You can see the center mark on the base board aligning with a center mark on the bottom of the base cabinet.

Next, I found the center of the arch and marked it. I now placed the base board on top of the base cabinet, aligning the two marks. Now I could mark the ends of the base board on the inside edge, where the miters needed to be cut.

The next task was to determine the correct angle for the miters. I have a Starrett Pro Site Series miter protractor that I got for Christmas a couple of years ago. I figured it was time to put it to use.

The photo above shows the miter protractor on the carcase on the first corner I wanted to wrap. The photo below is a close up on the protractor's scale. If you look closely, you'll see that the angle shown on the scale is 45°.

The red arrow on the protractor's scale is pointing to the correct miter angle for that corner, which happens to be exactly 22.5°. Somehow, I got that corner to come out absolutely perfect. The other corner turned out to be 44°, with the correct miter being 22°. So you see, you can't just assume the corners will be identical & perfect, you really need to measure them and cut the miters to fit each one.

To cut the miters, I used my Osborne EB-3 miter gauge. I left the saw blade set to 90° and used the Osborne's built-in detent to set it to exactly 22.5°. I raised the blade to full height & placed the outside face of the base board against the miter gauge's fence. I used my combo square to draw a square line across the back face of the base board at the place where the miter had to be cut. I carefully aligned the mark with the edge of the kerf in my ZCI & made the cut.

The offcut wasn't long enough to use for testing, so I cut another piece of scrap at the same angle. I placed both pieces on the base cabinet to check if the miters would line up properly. They met perfectly without any gaps. Now I made a matching piece from good stock, about 1/2" longer than I needed it to be after mitering. This also matched up perfectly.

I repeated these steps on the other corner. The miter angle had to be 22°, as I said before, and I had to make a couple of cuts to get the piece with the arch in it the right length.

The photo at the left shows the finished pieces, all mitered & clamped to the bottom of the cabinet.

My next task is to make the other moldings for the cabinet. There's a molding with a profile that I call an "ogee" that I have to make. It consists of a 1/4" radius round over, a 1/16" "step", a 1/4" radius cove, another 1/16" "step", and another 1/4" radius round over. This is going to be challenging to make, as everything has to line up in exactly the right spots or the wood will be scrap. I'm going to have to use a lot of scrap to get this right. Wish me luck!

3 comments:

Jeremy Z said...

The ogee molding you're going to make, I assume it is much larger than could be cut with an ogee bit on a router table?

Nice blog. (found it in your siggy at woodnet)

Mine doesn't have woodworking on it, mine's riding, which is out of season in Chicago now.

neil said...

Hi Tony...........Looking GREAT!!!

Tony.....the one photo shows that Bird-mouth joint in play perfectly. That Starret tool is kinda cool. I wouldn't worry about that .5 degrees you're off...that's probably better then John Townsend...heck, he probably wasn't as curious as you and didn't have the instrument to measure so exacting, he just cut to fit.
It's obvious you make your own luck, so that molding is going to be a wonderful challenge, so here's my wish that you just have fun with it.

Tony V said...

Jeremy:

The ogee isn't a normal ogee. I call it an ogee because it's a combination of two round overs & a cove, similar to an ogee. It's going to take three cuts with two different bits to make this molding. I'm going to post about it soon.

Neil:

I'm not sweating that half degree, I just wanted to point out to folks that you can't just assume everything's going to come out perfect. You have to cut to fit. My techniques are probably not the same as John Townsend's, but they work for me.

Anywho, I want to write an update tonight. See you in the funny papers!

Tony