Archive for December, 2009

Bench Dogs, more Bench Dogs, and a Mallet

Monday, December 28th, 2009

Low temperatures make the shop a “no cure zone” for epoxy, thus postponing the next boat building steps.

So, something else is in order … more tools. When I first built the workbench, I made a few simple bench dogs from some sort of not-so-hard Indonesian hardwood found at the Borg. They have served well, but have not lasted well. The remainder of a piece of Ash called out for use. It was left over from getting out structural parts for the Mill Creek 13 boat. I ripped off one strip to 1 inch by 13/16, and another to 3/16 by 13/16. The thicker piece was cut into lengths, making the bodies for 24 bench dogs. The thinner strip was cut into 48 pieces, making the top faces, and the spring pieces. photo of bench dogs and a malletThe springs get their action from being screwed onto a bevel at the bottom of each dog. One is shown resting on the bench in the photo. (As always, click the photo to see  larger version.)

The mallet is one of the “Two Mallets that Followed Me Home” from a while back. Several pieces from that small log seem dry enough to use. I have no moisture meter. My only measure is that the temperature of a freshly cut end is the same as a broad surface. A too wet piece usually feels cooler at the fresh cut. You also get juicy shavings when planing wood that is too wet. This wood made dry shavings. The mallet’s design is the age old design of fitting a tapered handle into a mortise in a rounded head with angled faces. I used no plan, cutting the parts to what could be gotten from two pieces of the log. The head is laminated from two pieces, gently curved across the top, and with faces angled 10 degrees from the handle’s axis. The top surface of the head measures 4 and 3/4 inches by 2 and 1/4 inches. The mallet will get a couple of coats of BLO finish shortly.

There’s more wood from that log, easily enough for the second mallet. Yet, maybe it wants to be a small turning saw instead?

Oh no, Don’t Chuck It

Friday, December 18th, 2009

You just picked up that old eggbeater drill. Looks nice. You look into the chuck and think “Oh no, looks worse than someone who’s been using their teeth to loosen axle nuts. She’s a gonner.”

Maybe not…

My entry about refurbishing a Goodell-Pratt eggbeater drill has had more comments than any other article. Questions continue to this day, with several asking about the chuck … and can a chuck with skewed jaws be salvaged? My experience is that the most common problem with these drills is mangled springs in the chuck. I can’t know how they get so mangled, other than knowing that they are relatively exposed and are probably caught and mangled when people aren’t careful enough in setting bits into the chuck. The answer is a resounding yes, IF (big IF) all the jaws are present. Most of the chucks of the eggbeater era, Millers Falls, Goodell-Pratt, and other brands, had 3 jaws. Count em. If you have three, let’s break the chuck open and fix it up.

There is a bottom pieced screwed into the chuck. Mine was rust free and opened rather easily. Your experience may vary. If needed, use a good penetrating solvent and lots of patience. I clamped the chuck into a machinist’s vise using pieces of softwood to prevent marring the knurling. I used only enough clamping pressure to keep the barrel from turning, and to avoid distorting its shape. My chuck had two very convenient holes in the bottom, and there’s probably a spanner tool out there somewhere that fits those holes. A pair of needle nose pliers did the job for me. Other chucks might not have these holes, or might have flats for wrenching. There’s a lot of variation. You may need to use vice grips or plumber’s pliers to open the bottom. Whatever you use, try to employ some padding and be gentle enough to avoid marring the piece.

(Click on any picture to see a larger version.)

Once the bottom is removed, you will find a thrust washer or some sort of device that is used to push the jaws into the barrel as the chuck is tightened. Lift it out. Then, we can see the remaining parts, the jaws and the springs that hold them apart. Of course, here we see a nicely arranged, well functioning set of jaws and springs. This is what they should look like after you finish refurbishing.

OK, let’s spread out the parts.

The leftmost picture shows the parts laid out in a line as they normally fit together. The center picture shows each part rotated 90 degrees counter-clockwise to give you another perspective. The rightmost picture shows the jaws, with one flipped to show the surface that mates with the inside of the barrel. Again, these are all of a working chuck. Yours will most likely have some really ugly looking springs, mangled twisted things that are the root cause of your chuck’s problems.

Let’s make some new springs. The first thing you’ll need is some spring steel wire of the correct size. As one of the following pictures shows, the springs in this chuck (two are originals) are made of wire measuring 0.0195 inch thickness. I rummaged through some old guitar strings (never throw anything away) and found a steel string that measures 0.0250 (for the guitar’s 3rd string (G)). That was close enough. If your guitar string drawer isn’t well stocked, try a local hobby shop or craft store and ask for piano wire. Otherwise, go shopping on the computer.

The outer diameter of my springs is 9/64 inch, a size that lets them fit easily into the holes in the jaws. The springs seat into the holes about an 1/8 inch. The length of each spring is 11/16 inch. A good spring fits very nicely over a 3/32 inch drill bit. Note well: there are lots of variations and the measurements for your chuck might vary. In fact, there are at least two different spring mechanisms, and you might have to craft springs a bit different than these. The most important attribute is ending up with three springs that have the same relative springiness. Their balance is what holds the jaws evenly spaced in the chuck.

I have no magic for winding springs. I didn’t even look for spring winding tools, as I only needed one or two springs, and don’t foresee needing such tools in the future. (Ooops, failed a basic galoot principle there.) I used a 1/8 inch drill bit (sorry for confusion about this in comments to the original article). I started by making a 90 degree bend in the wire. I then clamped a 1/8 inch drill bit in the machinist’s vise. The tail of the spring wire snuggles up against the bit and we start winding by pushing the free end of the wire around the shank of the bit. ( Kari, I forgot the manicure, yet don’t have any open wounds, like Roy.) Then, I simply wrapped the wire around the bit, trying to keep a constant spiral with the spacing of the original springs. Yep, it took a few tries to make decent springs.

Two suggestions: First, using the 1/8 inch bit, even though smaller than the desired diameter, worked for me because once the winding tension is released the spring expands. Adrian, a commenter to the original article, found that a 5/64 inch bit got him the results he wanted for his springs. Second, wind a length longer than needed, and cut it down to the right length.

Lastly, reassemble in reverse order. A similar article by Andy Seaman suggests using a thin film of light grease as you put the parts back together, and he emphasizes “less is more” with the lubrication. Also, Kirk Eppler, in repsonse to a query on the Old Tools List, posted a few pictures of yet another variant here.

See, you can get the old chuck’s teeth back into alignment. Enjoy your refurbished drill!

Eva Too – Bottom – and a Shop Desk

Wednesday, December 9th, 2009

The boat’s bottombottom board and small shop desk is 1/4″ plywood. It’s lofted, cut and shaped, an easy bit of work. My turning saw, set up with a fine blade, did the job with ease and left an edge with no tearout or splintering. As always, I’m not confident to cut exactly on the line. I stay a bit proud and then get to the line with a block plane.

Sitting on the middle of the bottom is a shop desk that I made recently. By design, I have very few horizontal surfaces in the shop and they are either covered with work in progress or too small to use for much more than holding small tools, cans, etc. The instruction booklets, or small paper plans (the big ones are pinned to the wall) have always been at the mercy of temporary space, leaving me to constantly ask myself, “Where’s the book? … Where’s the book?”

shop desk hanging on a french cleatSo, I finally did something about it and made a very simple little desk. I used no plans. I just hacked up a bit of old shelf material to make something of suitable size. A few simple dado joints are as fancy as it gets. This isn’t boardroom furniture; I kept it simple and functional. The versatile part of this little desk is the french cleat on the back. I ripped a mating cleat that’s the full width of the shop’s end wall. The desk can now be hung anywhere along that cleat.

While at it, I added a cleat to a pair of wire bins. These were good for de-cluttering another part of the shop.

For the sharp-eyed among you, the large sheet of plans hanging above show plank and bottom shapes along with their tables of offsets. … and the stuff on the floor in the corner is the black locust being saved for mallets.

As always, click on any image to see a larger version.

Eva Too – Lofting Along

Tuesday, December 8th, 2009

picture shows a smooth scarphOh, before we get too far away form scarphing, here’s a picture of how a pair of the scarphs worked out. Even continuation of the plies is exactly what we wanted.

This boat’s plans specifies the shape of the planks with a table of offsets. The planks and the bottom are lofted, not spiled like in the previous boat. The process is simple. Establish a straight reference edge along one edge of the material (good use of the long jointing plane). Measure off and draw station lines, one per foot for this boat. Take the offsets from the table on the plans and mark on the station lines. Connect the dots using a smooth batten to fair the lines.

sawing planksThen, saw as close as you dare to the lines and finish up with a block plane. The boat only has 4 planks, 2 sheer and 2 bilge. Cutting and shaping them in pairs is easy and keeps them identical. Once again, a lumberyard bench is nice to have because the easiest way to keep a pair of planks in alignment is to nail them to the bench.

Recent boat building isn’t getting a lot of time. This boat could be moving along a lot faster were there not a lot of other things I find interesting.

  • Flatbread “Bings” are the latest cooking discovery for this house husband. They are easy to make and disappear quickly.
  • Marveling at hand engraving and learning to draw some of the scrolls and leaves patterns is a new diversion.
  • Exploring wooden clocks, and considering making them…
  • Reading woodworking books such as “The Joiner and the Cabinet Maker” in which young Thomas learns a woodworking trade, and Tom Fidgen’s “Made by Hand” in which stunningly beautiful furniture is made using only hand tools.
  • Following “ClimateGate” and contrasting it with my many years spent in serious, principled scientific discipline.
  • Studying the Federalist Papers, in which the country’s founders discuss the merits of the U.S. Constitution. Today’s reading was #41 in which James Madison clearly delineates how the “general Welfare” phrase of Article 1, Section 8, is followed immediately by, and constrained by, a list of 21 enumerated powers which limit what the government can force upon us.

Tomorrow: cut and shape the bottom of the boat.

As always, click on any image to see a larger version.