Posts Tagged With: Making Tools

So, I have to cut 16 mortises, 3/16″ wide by 3/4″ long by 1/2″ deep in the 3/4″ square stiles for the Blacker House style sconce I’m making.  I did a few experiments with chopping these by hand and it’s too slow and fussy for my current skills.  I need to practice more, but I also want to get this light made.  So I decided to set up a simple router table to crank these mortises out.

Step one, I started scrounging on craigslist for a ready-to-go router table.  I don’t want (or need) another project.  I found a few for sale including a nice Jessem setup, but they were all way more money than I wanted to spend on something like this.  Several folks were selling the typical particle board and Formica tops with the plastic insert on 2×4 legs – for hundreds of dollars.  Not my cup of tea.  I was on the verge of making one from scratch when I found a guy selling a Bosch 1617 router and a steel Bench Dog table top.  This is a steel top that it meant to attach to the left side of a standard table saw.  It won’t work with my saw, but a router right there would be in the way after all (which is why this one was for sale).

I started with a simple sketch.

Long, Drawn Out Design Phase

I thought about making a cabinet base out of plywood, with drawers for bit storage and so forth.  But I also wanted to just get this done and operational so I could get on with my sconce project   So I decided on a fabricated steel stand.  I had some 2″ square tube on hand, so I cut app the pieces and de-burred it.

Steel All Cut To Length

Then went at it with the welder.  I tack welded all the parts and triple checked to make sure they were square.  The heat from welding will easily pull parts out of alignment, and in a few cases I chose where the next weld went to pull parts back into alignment.

Tack Welding

I took about an hour and a half to cut the tubing and weld up the stand.  I don’t think I could have made this in wood any faster.

Stand Completed

I added two tabs to the back to bolt the steel top in place using two of the existing holes for mounting it to a table saw.  The top is completely support by the steel tubing, the tabs just provide the attachmant to keep it in place.

Mounting Tabs

In place in the wood shop.  I made some practice cuts and the mortises are prefect.  Time to do the real parts now.  It’s simple and even with the steel base and top I can easily pick this up and move it around the shop.  I made it the same height as the table saw, so I can press it into service as an out feed support if necessary, although I plan to make a dedicated support soonish.  I need some way to store the extra router bits and wrenches, but I’ll deal with that another day.  I’ll need to add dust collection for this eventually.

Finished

A while back Christopher Schwarz asked if I could make a batch of the Studley Calipers for Lost Art Press, it took me a while to get going on it with all the commotion at work but I finished them up this week.

Machined Caliper Blank

I blogged about this before, I started with a picture and scaled it in SolidWorks, then essentially used that image as a guide to model the shape of the reproduction.  Visually it appears to be identical to the original, but of course I’ve never held the original in my hand.  Now if someone could just ship the whole Studley chest to me…  The original appeared to be stamped steel that was chrome or nickel plated, I made these in brass.

Machining the body of the caliper is pretty straightforward.  The real work was in the details.  Once the parts were machined they had to be cut free from the blank, the little retaining tabs sanded flush, the holes de-burred and re-tapped, and the faces hand sanded with 600, 1000 and 1500 grit sandpaper to make sure they look nice.  Then the real fussy work started.

Because of the small size of these, off-the shelf hardware is too big.  The pivots are small binding posts with #8-32 threads.  Both sides of the pivot and the base of the thumbscrew needed to be machined for clearance.  And of course clamping tiny brass screws in a collet tends to distort the threads, so I had to run a die over all the threads to clean them up.  Luckily Kolya was a willing participant.

Once all of the fasteners were machined, re-threaded and everything cleaned we turned up the music in the shop and assembled them.    If you want one the only way to get one is to attend the Handworks conference in Amana, Iowa on May 24-25 and buy one from Lost Art Press.  I’m planning to attend, hope to see you there!

Studley Caliper

I just looked at my new saw bench in the light of day. I like it. Milk paint rules.

I’ve been working too much lately, which is totally screwing up my shop time.  Between meetings this weekend I’m running the CNC to make parts for a customer.  I wanted to start on my saw benches, but didn’t feel like I was clear headed enough to do something that complex (and that’s just sad!)

I while I was feeding the CNC I poked around my shop looking for inspiration.  I found an old hunk of heavy industrial electrical conduit, steel plate, and some copper scraps — and decided I’d make a glue pot.  I sawed off a length of the conduit and sanded it to remove the zinc coating.  Zinc screws up the welding, and it’s toxic to breathe the zinc fumes.  I also cut out a disk of steel plate about the same thickness as the tube.

5″ Electrical Conduit

I welded the disc to the tube, mostly that went OK.  I’ve been welding so much cast aluminum for the past few years that I’m out of practice on steel (and everything else).  I had a little contamination from the zinc, and I had the weld too hot.  But mostly I was doing this on auto-pilot, trying not to think about work, so it’s not my best work.  But I kept the mill fed (every 18 minutes and 30 seconds I have to take out a finished part and put in a fresh piece of material) and I didn’t think about work at all.

Welding on the Bottom

I laid out and drilled two holes for the handle pivots.  I bent the handle out of some 1/4″ x 1/2″ flat steel bar from the scrap pile.

Drilling for the Handle Pivots

I pressed in two steel pins for the pivots and welded the end on the inside of the pot to hold them in place.

Handle Installed

Then I started on the copper liner.  The round tube is a 3″ copper pipe coupler.  The layout on the flat sheet is for the top, a hole for the tube, the OD of the steel jacket, and a small allowance for a turned lip to hold it in place.

Layout for the Top

I welded a copper disc on the bottom of the copper tube.  The steel block is just a weight to hold it in place.  Copper is funny to weld.  It conducts heat like crazy, the hole part gets hot before the weld will start.  It doesn’t really change color when it’s ready to  puddle either.

Welding on the Bottom

I ground the weld smooth after it cooled off.

Bottom Welded On

I used a 3.25″ hole saw to cut a hole in the middle of the top sheet, then used a beverly shear to trim the part to the outside layout line.

Make a Hole for the Tube

After welding on the top flange and grinding the weld smooth I hammered the edge over so it would register on the steel jacket.  The work isn’t perfect, but, again, I didn’t think about work at all so I’m pretty happy with it.

Copper Liner Finished

I gave the steel jacket a couple of coats of high-heat semi-gloss black engine paint.  I’ll let that dry for a day or so, but otherwise it’s ready to put to work.  I need a wood project now so I can try it out.  I’ll probably make a lid some day, but I’m done for today.  It’s a heavy glue pot, it should hold heat really well, I can’t wait to try it!

Finished Glue Pot

Another View

A while back I started making a marking gauge.

I set it aside for a while – in part I’ve been working on my bench, but also because I wasn’t sure what I wanted to do for the cutter on this gauge.  I’ve seen folks use a pointed piece of drill rod, but that doesn’t work well across the grain.  I’ve seen instructions on how to sharpen this kind of cutter to make it more of a knife part, but it still looks too thick to slice through the wood fibers nicely.  David Charlesworth write about this in one of his books, this picture is from a Popular Woodworking article:

I really like my Glen-Drake gauge, I like the way that it slices through the wood and leaves a crisp line.  I’ve seen marking gauges that use small blades and even X-Acto knife blades.  The downside of that approach is that the attachment is a bit more fiddly.  I wanted this to be simple and fast, here is what I came up with.

I’m using some 5/32″ O1 drill rod — this is an oil-quench tool steel.  I chose the diamater because I wanted to fit it into a 1/8″ hole and have it be a snug fit.  I cut a few short pieces with a hacksaw and de-burred them ends.  Note that I filed one end flat and a small dome on the other end. (I swear, this was in focus when I took it)

I heated the rounded end using a propane torch, the hottest part should be right at the tip of the inner flame cone.  I’m holding it a little too far into the flame in the picture, but I’m juggling the part and the camera at the same time.

Heat the tip until the first 1/3 or so is a cherry red.  I’m going to forge the end into a flat, fan shape.  Forge might be too strong a word, this is pretty light work.  I used light taps and re-heated it after a few taps.  Between the small size of the part, and the mass of cold metal in the hammer and “anvil” it cools off really quickly.

To get the shape I wanted I need to hold the hammer at an angle, and hold the part at the edge of the anvil so that the hammer can hang off the edge.  This is a posed shot of course, I couldn’t hold the hammer, vise grips with the red-hot part and the camera all at the same time.

What I’m working toward is to thin the metal at the tip, tapering back to a round cross section, while widening the metal at the same time.  It’s harder to type than to actually do it, trust me.  It took me maybe 3 or four cycled of heating and hammering to get to the shape I wanted.

Next I needed to harden the metal so it would hold an edge.  There is a lot of science in heat treating, and a fair bit of black magic when it comes to making edged tools.  I’ve forged a handful of knives and chisels in the past, forging edged tools is a bottomless pit of austenitic temperatures, molten salt baths and cryogenic cycles.  For the purposes of making a pointy thing to leave a deep scratch in a piece of wood, simple is fine.

Heat the part to a medium cherry red.  If you have a magnet handy the part should loose it’s magnetic attraction at this temperature.  Then stick the part into a small container of oil and swish it around.  Done.  Technically it should be “tempered” to draw out the brittleness, but it’s not necessary for this.

Please use caution if you do this yourself, it’s all too easy to burn yourself or set something on fire if you’re not careful.

You can confirm that you’ve hardened this by using a file.  A slightly dull file (I have several of those left over from retoothing my saw) should skate across the hardened area without cutting.  Compare it to a piece of the same material prior to hardening it.

Then I worked the tip with a grinder, then an oilstone.  The tip is wide and thin, less than 1/16″ at the edge.

I still need to sharpen it, and finish the rest of the marking gauge, but I think this will work out well.