Tuesday, October 7, 2008

Some Assembly Is Required

The raised panels are shaped & finished. The frame parts are all made. It's time to do some box assembly! The crowd goes wild!

Well, almost. There's a few odds & ends in the way. You see, I found out during one of my dry assemblies that some of the shelf pin holes I drilled weren't deep enough. My fault for not testing my set up on my plunge router. I even missed a couple of holes on one post. Considering there were 12 posts that needed shelf pin holes, that's not bad. And I hadn't drilled all of the pocket holes I need, either. And there were a few parts that needed more sanding. And I found a couple of gashes had magically appeared on a couple of parts. And I still had to cut the notches on the 10 shelves I had remade a couple of weeks earlier.

In fact, I made a list of 31 steps I needed to perform in order to complete the assembly. These included things like cut the notches in all shelves, sand the shelves, disassemble a box, re-drill the shelf pin holes, etc. Hey, I'm detail oriented & anal, what can I say?

So I took a Friday in September off from work & got to item #1 on my list: Cut the notches in the shelves. And that took all day to do. So much for the best laid plans of mice & men, eh? I am happy to say that they came out much better than the last bunch of shelves I had cut.

To do these, I set my combo square to the depth of the front posts on one of the boxes and I used that to set the height of the blade on my table saw. I also used it to lay out the depth of the notches on the front corners. Then I set my combo square to the length of the notch, and I used it to lay out the length of both front notches on both top shelf blanks.

Next, I took my stock miter gauge, which still had the auxiliary fence I had installed the last time I cut notches attached to it, and I made one cut. Just one. And I took the shelf over to the wing I had used to measure everything. And the cut was too far from the corner -- it looked like I'd screwed it up again.

Blood pressure rises. A primal scream escapes the lips. Luckily, the kids were at school & the wife was out running errands. Time to break for lunch.

While eating lunch & cooling down, I realized that maybe I hadn't screwed it up after all. You see, the wings have one side made with 3/4" ply glued into rabbets in the 2" x 2" posts, and the other side was designed with 3/4" rails, but which I had changed to 7/8" rails. So the two front notches shouldn't be the same length. So after lunch, I held that shelf up to the other wing & sure enough, the cut was spot on perfect. Whew!

At this point, I abandoned laying out the notches. Instead, I just set my combo square for the length of the notch in question, put the body against the edge of the shelf & adjusted it so the end of the ruler touched the edge of the aux fence. Then I put a spring clamp on to hold everything in place & made a pass. Then I nibbled the rest of the stock away for that corner.

This worked very well. Due to the solid edging being wider than the ply's thickness, I couldn't do both front notches with the miter gauge in the same slot. I had to move it to the other slot & remount the fence to get the other notch done. I fumbled the order of cuts & had to do that about 2 or 3 times. But I got them done.

I had to do a little clean up with my chisels & some sand paper since I have an ATB combo blade mounted to the saw. And this did take all day. But I was feeling a lot better about the shelves.

The next day, a Saturday, I got started on the right wing. I disassembled it & did all of the items on my list for that wing. I drilled holes in the top shelves for brass cup holders. I drilled pocket hole screws in the top & bottom shelves to draw the posts in tight after assembly. I re-drilled the shelf pin holes, and drilled the two missing holes in the post that needed them. I sanded everything with my ROS & with 180 grit paper by hand.

All of this took a bit longer than just that Saturday, but it was time well spent. And when all of it was done, I did one last dry fit to see how & in what order I'd put everything together. All set for doing it for real!

I got home from work on Tuesday & I glued the end panel together. This took longer to do than I thought it would. Unseen checks in the stock that I used to make a couple of the stretcher / shelf supports in that wing caused the wood to split pretty badly when I drove the pocket hole screws home, so I had to remake those. This time, I used ply scraps & ironed on some red oak edge banding I had left over from my DVD cabinet project to hide the ply edge grain.

I put it together on top of my table saw (I did put a drop cloth on top to protect the cast iron from glue drips). I squeezed a dollop of silicone caulk on to the edges of the raised panels & buried a Space Ball in each one. Then I spread glue on one tenon of the bottom rail & put it in place, carefully aligning it with the bottom rabbet on the post.

Next the bottom panel went in, then the middle rail, followed by the top panel & lastly the top rail. I spread glue on the tenons & in the mortices & put the other post on. I used three 24" K body clamps to pull the assembly tight. Next I spread some glue on the ends of the bottom stretcher and the edge that contacts the bottom rail. After using my spacer block & clamps, I drove the pocket hole screws home for the last time. Then I spread glue on the ends only of the top stretcher (this one doesn't contact any rails) and screwed that in place.

I had to put a long clamp vertically across the front of the assembly to get the top & bottom rails in their proper places, even with the ends. I finished up at about 9:00 pm, which is my usual knock off time when I work on a week night.

I'm happy to say that the assembly came out flat and square. Praise the Lord!

The next night, I worked on the final glue-up for that box. This consisted of gluing the bottom shelf to the bottom stretcher, keeping it square, and driving screws through the stretcher into the shelf. The front bottom stretcher was then glued & screwed to the bottom of the corresponding shelf edge, and then a pocket hole screw was driven into the post. Pocket hole screws were driven into 2 pocket holes in the front shelf edging (which is 3" wide). I then repeated this process with the top shelf, which used 1 fewer pocket hole screw.

At this point, it's time to attach space balls with caulk, spread glue on tenons & insert the rails & panels. This is the stressful part of the glue up, since you have to get the glue spread on all of the joints & everything put together & clamped within the glue's open time.

I got it done. I was busy working on it until 10:30 that night, but I got it done.

I then started to work on the center box. I took the box apart. I cleaned up a few gouges. I re-drilled the shelf pin holes. I even glued the bottom rail into one side. I did this because I had some trouble getting everything square & I thought having this glued into one side before doing the full glue-up would eliminate this issue.

Then I tried to do a dry fit. And I found that the panels I had made for it were 5/8" too wide! This meant that the top & bottom rail were 1 1/4" too short, and the center rails were 5/8" too short. Time for some more cursing. Pack it in for the day. And figure out how I'm going to fix this one.

Thinking about it, I saw I had two ways to fix it:

  1. Remake the rails longer
  2. Cut the panels narrower & refinish them.

Option 1 meant I'd have to cut out the bottom rail I had glued in previously and throw away the parts I'd already made. Not really desirable. Option 2 meant I'd have to strip the finish off, cut the panels narrower, re-route the raised profile, then refinish everything, matching any finish I'd left on. I found this idea to be daunting -- I'm OK at finishing, but it's not my strength.

At this point, I contacted Neil Lamens from Furnitology Productions via email to ask his opinion. He recommended I cut the panels down. His reasons were sound -- keep the project moving, and remaking the parts is expensive. I would have to buy more lumber. And machine set ups are difficult to repeat.

In the end, I decided just to remake the parts. Since this piece is being made as a donation for my church, the usual economics don't apply. I can just include the costs for the additional wood in the value of the donation at tax time. And frankly, it would take me a lot less time to remake the parts than it would be to just strip the panels down.

So I went out out & bought another piece of lumber. And I put the center box aside & put the other wing together. I needed to let that wood acclimate after all, and putting the other box together would help to keep some of the momentum going. Besides, I'd have to change the set up on my plunge router, which was set up to do shelf pin holes, and I didn't want to do that until I was done using that setup.

This one went together well and a little faster, having had the practice from the first box. While I was at it, I also drilled the holes for the bolts & the threaded inserts that would hold the finished boxes together. Here's a picture of the two boxes with the sides of the center box attached to each box.

The two boxes are about as far apart in the picture as the center box will be wide when finished, so you can get a feeling for how big the finished pulpit will be.

That's enough for now. Part 2 will follow soon.

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