Monday, March 24, 2008

Making Doors

In the last installment, I went over the calculations needed to size the door parts for their intended openings. Once I had a set of dimensions I felt were good, I went to work making the parts.

The first step was to prepare the boards that were to become the two center panels. The panels are 1/2" thick & are to be glued up of three 6" wide boards. I cut everything to the right lengths & ripped to the correct width. And then I put the boards next to each other & tried different arrangements until I found a combination that looked good, with the grain at the edges chosen to try & make the joint disappear. After getting the boards just the way I wanted them, I drew a big arrow head across the three boards. This would allow me to put the boards back together again in the correct orientation & combination later.

Looking at the joints, I wasn't happy with their fit. So I decided that I would put off gluing up the boards until I made a trip to Woodcraft & used their DJ-20 to straighten the edges. At that point, I went ahead & ripped all the rails & stiles to width and then cut them to length.

Next, I set my dado set to 1/4" & mounted it on the saw. I set the fence so there was 1/4" between it & the dado cutter. I placed my GripTite feather board in place & cut the grooves in the rails & stiles for the panels & stub tenons. I cut the grooves by making a pass, then swapped the board end for end & made a second pass in order to make sure the groove was centered.

After that, I widened the dado stack to 5/8" & mounted my auxiliary fence to the rip fence. I set the auxiliary fence so there was only 1/2" of the cutters exposed and then raised it high enough to remove about 1/4" of material. Using my Osbourne EB3 miter gauge and the fence as a length stop, I ran one end of the rails through the exposed part of the dado. Then I turned the board over and made a second pass. I then flipped the board end for end & repeated cutting the tenon on the other end. I repeated this process for each rail & so formed all of the tenons.

I then put the frames together without the panels, to see how the fit was and to see how the resulting frames fit in their openings. It was at this point that I discovered I had some how cut the rails for the upper door about 1/4" - 3/8" too short. I'm not sure how that happened; I guess I had a brain fart. I had enough extra stock, though, so I just made two new rails & this time I got the length right.

At this point, I put everything aside, as I couldn't really go any farther until I glued up the center panels.

The following Monday, after work, I drove directly to Woodcraft in Norwalk. When I got there, I found that Frank, the gentleman who had been taking care of the machines at this shop, was not working there as often anymore. There was a younger fellow there working on a drum sander. I went ahead & started to edge joint my first board. After I made a number of passes, I found that the jointer was out of alignment. I was not getting a complete cut all the way across the edge and the board was quickly becoming wedge shaped.

To make a long story short, someone had moved the outfeed table on the jointer, which the rules of the shop say you're not supposed to do. Further, the new guy, using only a 6" long try square, never got it set back up properly. So I just took my boards back home & ripped them to width again carefully. I got better joints, good enough to glue them up.

The glue-up was problem plagued. Before I decided to rip them, I just tried to glue them up based upon what the jointer did to them. The boards kept popping apart when I tightened up the clamps. After two attempts the first night, I just gave up & tried again two nights later. It was at this point that I ripped the boards carefully and finally got two good glue-ups.

I used cauls across the surface of the boards & got very closely aligned faces. You couldn't really see any misalignment, but you could feel a0 very slight difference in height. A little work with a card scraper & my ROS & the boards were perfectly flat. In fact, placing a straight edge across the glue-up, you can't detect any light between the board & the edge.

After cutting the finished glue-up to final width & length, the next step was to cut a 1/2" wide by 1/4" deep rabbet around all 4 sides of the back of each panel. This was to get the edge of the panels to fit into the grooves in the rails & stiles. I couldn't make the panels 1/4" thick because after gluing up, they're too wide to fit into my 12.5" planer.

Actually, the upper rail has a 5/8" tall arch in it, so the groove in the upper rail (& the corresponding rabbet on the upper panel) have to be 5/8" + 1/2" or 1 1/8" deep. I decided to make the groove before I cut the arch. The reason being that I I didn't want to cut the curve all the way through the thickness of the rail. I thought the extra deep rabbet would have looked weird if part of it was exposed on the back of the door.

The picture below is of the lower door, dry fit together after all of this work was done. It came out pretty good, if I do say so myself.

The picture below is of the upper door, again after all of the above work was completed.

That's enough for now. More on the doors & shelves next time.

Wednesday, March 12, 2008

The Doors

When we last met, I had just finished making & applying all of the molding to the carcases. Since then, I've either been sick or on the road, and I just haven't had a lot of time to post anything. I apologize for taking over two weeks to make this post, but sometimes life gets in the way.

The time has come to start work on the doors. I'll take you through some of the planning I had to do for the doors in this post, and we'll get into the actual woodworking next time.

The dimensions of the doors are determined entirely by two factors:

  1. The size of the opening
  2. The style of the door: inset or overlay.

Overlay doors are larger than the opening & so lay over it when closed. The edges of overlay doors are rabbeted, forming a lip that so that part of the door fits within the opening. Overlay doors are easier to hang, since you can't see the opening & can't tell if any of the corners are out of square or not, and you can't tell if the door is perfectly centered within the opening.

Inset doors fit entirely within the opening. Inset doors usually have a uniform space between them & the opening for the best look. The size of this space is usually determined by the hinges that you use to hold the door on to the cabinet. Since the opening in the carcase is actually visible, its corners must be perfectly square to each other. If the spacing between the door & the opening isn't uniform, you can easily tell that the door isn't centered properly in the hole.

The doors for this cabinet are inset doors, since all of the doors on the rest of the pieces in our dining room set are inset doors. The door hinges I am going to use are the same as used on those pieces, and are a morticeless type that are 1/16" thick. Due to the hinges, there will be a 1/16" space between the door & the face frame on the hinge side. For these doors to look right, this 1/16" space has to be consistent all the way around the door. This means that the height of the door has to be 1/8" less than the height of the opening, and likewise, the width of the door has to be 1/8" less than the width of the opening.

In addition, the doors are actually wrapped by a 1/4" thick bead molding. So the lengths of the rails & stiles for the door frame need to be an additional 1/4" smaller than the opening size.

Now, one of the things I've learned is that when it comes to fitting things like doors, the best thing to do is to actually measure the opening the door will fit into & use those dimensions to size the door parts. No matter how well you follow a plan, there are always little errors made in measuring & fitting things together. According to my plan, the width of the two door openings should be identical. Well, it didn't turn out that way. The bottom opening ended up being about 1/16" wider than the top opening. It's no big deal, but actually cutting to fit will keep the gap around the doors consistent.

Below is a screen capture of a spreadsheet I put together that computed the dimensions of the parts I need to make for the doors. When I make the parts, I won't just rely on these dimensions. The idea is to start here and make sure that everything fits properly before glue-up.

Now, as luck would have it, I made some mistakes when originally measuring some parts for the doors when I was putting together my SketchUp drawing. When I measured everything then, some how I came up with a width of 2" for the rails & stiles, and the bead molding being 1/8" thick. I had originally plugged these dimensions into this spreadsheet and had cut everything to length based upon the assumption the bead would be 1/8" thick.

I was having a very difficult time finding 1/8" diameter beading bit. I thought I found one, but it turned out to be a 1/4" diameter bit (I guess I misread the package). So I went back to one of the pieces in the set & measured again. It was then that I found somehow I had mismeasured. The rails & stiles are supposed to be 1 3/4" wide, and the bead 1/4" thick, making for a finished dimension of 2" on those parts.

At this point, I decided I could go ahead & use the 1/4" diameter beading bit, but I had to change the dimensions of the rails & stiles so the finished doors would fit in the openings properly. I couldn't change the length of the rails or the width of the panels, because you can remove material, but you can't add material back. So I had to rip 1/8" off the width of each rail & stile, and then cut the stiles 1/4" shorter to get everything to fit.

As a result the actual dimensions of everything differ from those in the spreadsheet by 1/8" to 1/4". So long as the final door dimensions match those shown in the spreadsheet, the door will fit and no one will know. It's a pain to realize this late in the assembly that you made a mistake so early in the planning, but that's life.

Next time, I'll detail the adventures I've gone through getting these doors built.