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, March 21, 2009

Building the Jointmaker Pro (Part 1)

Christmas continued at my house this week with the assembly of the Jointmaker Pro. I received the unassembled version of the Jointmaker, which provided a great opportunity to understand exactly how the machine goes together.

Before starting, I cleared and vacuumed the benchtop. I only wish I had also vacuumed the floor: there are a lot of small parts (with no extras), and I managed to drop three of them. The game of hide and seek would have been easier on a carefully cleaned floor.

The tool parts arrived securely boxed. Inside they were packaged in protective plastic bags, carefully wrapped in paper, or nestled in perfectly-sized high impact Styrofoam compartments.

As I mentioned in my previous post, there are a lot of small parts and the assembly requires a lot of patience and care. If I had not had such short lengths of time to work in, and not taken so many pictures along the way, I think it would have taken about three hours to assemble. As it was, it took about 4.5 hours plus time to solve the two troubles I encountered (more on this later).

The hardware was divided into manageable groups of parts, and I kept them in their bags until I neared the end of the process. The logic of the sorting was not always obvious, but there was a logic: all of the same sized screws were in the same bag, and all of the orange aluminum parts were in the same bag, all of the square topped bolts, etc. When I looked for a part, it was usually in the bag I look in first.

In addition to the Allen wrenches Bridge City shipped with the kit, they mentioned the need for a #2 Philips head screw driver, a small hammer, a 9/16" open ended wrench (or adjustable wrench), and needle nosed pliers. I quickly found that a small, accurate square was also required for referencing some of the parts, and I wished many times for Allen wrenches that had screwdriver handles for the two largest sizes that Bridge City supplied.

The front and back panels were wrapped in individual heavy plastic bags to preserve the quality finish of the tool.

The stretchers each had a perfectly fitted seating on the back of the front and rear plates. These were then easily screwed into place.


Doesn't it look good already? But a tool looks good because it works well, so there wasn't too much time spent admiring it. I didn't get nuts with the pictures until later in the assembly process (I really did go nuts), but assembling the shafts to the keel was when the square became useful: it was the perfect tool for ensuring that bearing blocks are square and flush with the keel edges. There are pictures in the manual showing exactly how the gears should interlock. At first it seemed to me that I couldn't do this incorrectly, but the slots in the keel allowed some play in the positioning of the shaft. I found it easiest to check the correct placement by feel: the gears should interlock so that the teeth meet on exactly the same plane.

A blurry picture of the gears after both shafts are attached:

With the shafts assembled, the working part of the tool starts to take shape.

I found the hardest (most nerve wracking) part of the assembly to be inserting the spring pin that attaches the front height shaft to the spine. Needle nose pliers truly were necessary for this, and though the instructions recommend using a small hammer they don't make clear how hard that hammer has to strike to drive the pin home. Too lite and the pin just waggled around. It took a solid blow to get it started enough to abandon the pliers and pound directly.

With the pin fully seated, this is what the connection looks like.

Next, the front and rear height shafts are screwed into the keel. This is where the work of raising and lowering the blade takes place. The instructions have specific lengths mentioned that should protrude from the gear bushings. This was another place that I found the sliding combination square handy: I set the rule to the required height and used it as a depth gauge.

After this step, the keel was held upright in the bench vise, as recommended in step 7. The pitch adjuster screw was inserted and the rear spine guide attached (again with the combination square to seat it properly square and flush to the keel). The next part involved tightening down a screw that threads into the rear pitch adjuster until it is tight, then backing it off slightly. This captures the spine between two washers and allows free movement of the screw while the spine pitch is adjusted. A simple and elegant solution.

Notice the Allen wrench in the top of the spine. There is a very small hole there for inserting this into the trap screw, and the instructions have two names for this screw. I note that one writer on the Bridge City forums had quite a time finding this, and if I hadn't done this in the same sesiion that I threaded the pitch adjuster and trapped the spine, I might also have had troubles.

That ends the first part of the assembly. I'll post the other half of the pictures soon.

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