Shop Made Tools

[ezduzit]

...it seems a little much to think that the back side of the chisel needs to be mirror smooth to chisel wood properly...

The smoothness is not required for the act of chiseling the wood, but rather so as to produce a very sharp tip without flaws which will tend to fracture the tip.

[Dan Krager]

At the risk of wandering from the topic, I would like to add that 65 years of chiseling in wood has taught me that smooth sharpness is definitely a requirement for cutting wood fibers cleanly. A woodworker uses his cutting tools and observes the finish left behind in the same manner a machinist observes the finish of his cuts. Similarly the durability of the cutting tool. How to obtain that sharpness and durability is one of the many arbitrary routes to a goal.

Back to shop made tools.

DanK

[qwerty12345]

Check out the "ruler method". I use something thinner than a ruler, a piece of spring steel, and it works great.

The basic idea is you only work the very edge of the back of the chisel (or plane iron, or whatever). When you are flattening the back, place the thin metal ruler, shim stock, etc. beneath the chisel near the back of the blade, closer to the handle (in between the chisel back and the stone or abrasive surface). This tilts it up slightly so you're really only working the edge (though you will bow it a little by pushing on it).

You get a mirror finish close to the edge, and the fraction of a degree the edge area is off from the rest of the chisel back is irrelevant in practical use. Much faster than making a back substantially flat (I spent a lot of time doing that before moving on to the ruler method).

[BMW Rider]

As a woodworker having done more hand tool work in the past couple years to grow my skills, I can assure that a well sharpened chisel with a polished back makes a big difference in the quality of the cut. Not a big deal if you just doing rough work, but for finely trimmed shoulders of a tenon or a tight fitting hand cut dovetail, it really matters to be precise. Polishing the back is usually only needed once when the chisel is new (some higher end tools are polished when made). After that only rarely will it need much further attention with just the micro bevel on the cutting edge needing honing to re-sharpen.

[ftownroe]

Just a very simple project to overcome a problem I encountered when trying to support the end of short stock sticking out of the side of the vise that needed to be drilled when the base of the vise prevented getting the support in close enough to use.

[Bruno Mueller]

I bought a touch probe from the Swiss company Tesa very cheaply. The clamping bolt was too short for me.
I made a slightly longer clamping bolt for the probe.
I ground the cutter for the dovetail from a Ø 4 mm HSS turning steel on the graver grinding machine.
The holder is fixed to the touch probe with an M5 grub screw and a pressure piece.

The pictures explain more.

This is the touch probe in its box.



Components from left to right.
Thrust piece - clamping bolt lying on the thrust rod - grub screw.



Part assembly



Mounting on the touch probe.


When grinding the dovetail cutter.

[BCRider]

Is that holder for use in the mill for small holes only? Or is it part of something else?

Bruno, you're lucky you have the grinder. No grinder here but I made a dovetail cutter for these indicators as well.

I turned mine on the lathe from some 3/8" drill rod. Gullets were cut with a finer size radiused corner end mill. Coarse relief filed by hand then the last edge relief stoned by hand with a stone file, inked edges and high power magnifier. Those lines in the picture are mm's as you can imagine. Hardened and tempered of course.

Done a couple of holders using it now. One in steel and two in aluminum. It's working well. And yes, making our own tools is great fun.

[chip's]

Nice job BC!

[BCRider]

THANKS! It's likely not as true as Bruno's but it's not a sliding dovetail. So if the angle is a whisker out it's no big deal as long as the indicator doesn't wobble, right?

Sadly the things I put the dovetails into were not as well thought out. I "winged it" and found that the face ran into the post and the thumbscrews once big enough to use also fouled the body of the gauge. So that one got tossed. Saved the thumb screws though. Winging it is NEVER a good idea in machining apparently...

The first that was done in a hurry to indicate a hole and why I made the cutter to start with is shown below. It was the first holder I did other than some test cuts in aluminium scrap to learn how deep to make the dovetail so it provides a proper fit. It was done to fit directly into a 1/2" collet and dial in a couple of holes. It was also before I bought a cheap Indicol holder. So again not much thought was given to making it somewhat more universal. But perhaps it'll fit in with some other bits I make at some point to expand it's ability. Notice that it's a two way holder. There's a longitudinal dovetail as well as the end face dovetail.

And the third one I can't find anywhere at the moment. It's intended as a replacement for one on a Noga arm clone which is total rubbish. It's in a container that I can't find just now. The silly thing is I recall exactly what the container is but not WHERE!

[Bruno Mueller]

I took another picture of another view.

[Bruno Mueller]

THANKS! It's likely not as true as Bruno's but it's not a sliding dovetail. So if the angle is a whisker out it's no big deal as long as the indicator doesn't wobble, right?

Sadly the things I put the dovetails into were not as well thought out. I "winged it" and found that the face ran into the post and the thumbscrews once big enough to use also fouled the body of the gauge. So that one got tossed. Saved the thumb screws though. Winging it is NEVER a good idea in machining apparently...

The first that was done in a hurry to indicate a hole and why I made the cutter to start with is shown below. It was the first holder I did other than some test cuts in aluminium scrap to learn how deep to make the dovetail so it provides a proper fit. It was done to fit directly into a 1/2" collet and dial in a couple of holes. It was also before I bought a cheap Indicol holder. So again not much thought was given to making it somewhat more universal. But perhaps it'll fit in with some other bits I make at some point to expand it's ability. Notice that it's a two way holder. There's a longitudinal dovetail as well as the end face dovetail.

And the third one I can't find anywhere at the moment. It's intended as a replacement for one on a Noga arm clone which is total rubbish. It's in a container that I can't find just now. The silly thing is I recall exactly what the container is but not WHERE!

The slit is a good idea, a too big dovetail can then be pulled together a bit. However, there is then also the danger that the counterpart on the probe will be damaged.