Sunday, April 12, 2009

Building the Jointmaker Pro (Part 2)

In the last post on assembling the Jointmaker, I forgot the picture of required tools. The Allen wrenches came with the Jointmaker, but everything else you'll need on hand. The (accurate) 6" square was extremely useful. The small hammer and needle-nosed pliers were only used once, but without the pliers, it would be very hard to drive the spring pin.

These tiny Phillips head screws hold the saw blade into the spine. I used the longer screw driver to put them in initially, but later (when tightening the blade in) I found the stubby driver to be the right choice.

Here's a picture of the spine with screws in place (though not tightened).

Next was the attachment of saw blade guides. This required the screws and washers pictured above. Notice the very thin washers: these are just .010 inch thick and sit between the saw blade guide and the front spine guide. Getting them in without dropping them was a challenge.

The first guide went on without a problem, and I was pleased with the speed and ease of the assembly. But the second guide occasioned much swearing: Everything seemed to be going well, until the front screw bound up. I backed it out, reseated it, and tried again with the same result. The screw would not go, and I was not going to force it.

I examined both the screw and the tapped hole. The screw had a white residue on the front of it, and the threads inside looked like they might be stripped. I panicked and immediately wrote to Bridge City tools (both to John Economaki and Michael Berg - the production manager. At least for now, their email addresses are included in the User's Guide. And even though it was the weekend, I received a reply from John before the end of the next day. Had I tried scraping the threading gently with an awl, or something else pointed? There might be some gunk in the threads.

The awl couldn't get the right angle, so I made a tool with a small brad:

Sure enough, what looked like cross threading was gunk. After scraping the threads thoroughly, I tried assembly again. This time I could drive the screw past the problem, and a few runs back and forth wore away what was left of the gunk.

Now the entire transmission was assembled. For some reason, the auto focus really didn't want to focus on the anodized aluminum. The picture above was the best I could do (it focused on the thread adjustment).

The instructions called for a transmission check, holding the unit in a bench vise and temporarily attaching the handle to take it, literally for a spin. Everything worked as described: I was ready to install the transmission in the table.

The travelers hold the transmission square to the front and back, and ride in the protractor slots at the front and back of the unit. Notice the white spots on each of them: these are nylon set screws that allow width adjustment to take out slop (there wasn't much) in the fit between the travelers and the front and back plates. The fitting was done before attaching the keel assembly to the frame.

Here's the front traveler being fit to the frame.

The keel is slid through the back plate.

The shaft is inserted into the front traveler.

And the back of the keel rests on the back traveler. Now the keel can be attached and adjusted.

And we're ready to attach the travelers to the front and back plates.

Locking knobs and nylon washers, which prevent damage to the aluminum front and back plates.

The knobs, once installed, will hold the keel in place. These are only finger tightened lightly until adjustments are made to the keel.

The jam nut will hold the handle in place with friction once it has been seated.

The handle screws on, and...

The jam nut is tightened against the bottom of the handle.

These four screws secure the keel on the travelers.

Notice on the shaft, the three nuts. These are part of a clever system for setting depth of cut for exact repetition. The stop that fits there allows perfect depth of cut every time (assuming you set the depth right in the first place).

The saw is beginning to take shape. Now it needs the sliding tables.

There are four dovetailed ways that for the supports for the tables and six aluminum spacers that make two rigid tracks for the tables to ride on.

The tracks slide into the front and back plates to form the rest of the frame.

Now there is a lot more screwing to be done, in the literal sense of the word.

I'm not sure how many screws are seated and tightened during assembly, but there are a lot of them.

Once the tracks are tightened lightly, the tracks are checked and adjusted to make sure they are coplanar.

These four sliders fit the dovetailed ways and make the suspension on which the tables ride. The bumpers prevent damage to the sliders by preventing them ramming into the front and back plates.

Here's one of the sliders after attachment.

And one of the bumpers installed next to it.

One of the sliders for each table has screw holes, the other has slots to allow adjustment back and forth. The one with slots is not fully tightened and once the tables are placed on the ways, with the sliders riding in the dovetails, you pull the slotted slider toward the edge of the table before tightening it down.

The fences attach with square headed bolts, that ride in slots on the bottom of the table.

This is a dovetail nut, which fits into a sacrifice fence and holds it in place. I'll probably want to get a router bit that cuts a matching dovetail at some point, so I can replace the fence when it gets too worn.

The dovetail nut attaches to the front of the fence.

Saw teeth on a seriously thin and well sharpened blade.

The blade inserts between the saw guides and is tightened into the saw spine. Easy to do.

Flip stops allow repeatable angles. There is a track on both the front and back plates. Set the blade at the correct angle, but a flip stop up against it, tighten it down, and you have an instantly repeatable setting that can be moved out of the way when not in use.

Installation of the flip stops requires some coordination, but with a thumb through from the back, and an index finger holding the square nut in back, it goes on quickly.

After all these pictures, I can't believe I didn't take one of the full assembly, but I didn't. I managed to secure the saw to the table and take some test cuts: smooth as glass.

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Saturday, April 11, 2009

Compost Bin Design Session

Today I assembled two thoughts for compost bins:

The first is built on a foundation of cinder blocks and has hardware cloth on three sides for ventilation. The fronts are prevented from spreading by a 2x4 attached across the front.

The second is modeled on a traditional New Zealand Box design that I found in the book "Let it Rot". The posts are driven directly into the ground and the slats on three sides are attached to the posts with half inch gaps between them for ventilation. Across the top is a "spreader bar" that prevents the tops from bulging out under the weight of compost. Both have slats that can be slid in at the front to build a taller pile that doesn't fall out.

We'll probably build the second one, because it hides the contents from the neighbors—somehow eggshells and vegetable scraps don't inspire confidence in the modern world, and we've removed many of the bushes that once obscured the compost heap from public viewing.

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Wednesday, April 1, 2009

More Handsaw Practice

I haven't had much time in the shop. I have been ducking in for 5 minutes at a time to practice cutting to a line, though, using the method described in and earlier post.

I'm getting pretty good.

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