Thursday, October 25, 2018

Guest blog bu Ty Stange: First Danish Chair Building Extravaganza

Thank you to Brian to let me post on his blog. This post is long overdue - life and business made sure I have been busy. Better late than newer - here goes:

This year I was given the honour to attend Danish Chair Building Extravaganza. Having newer met any of the attendants I did not know what to expect and what would be possible to make etc. On arrival I was greeted by Brian and Jonas in the yard and they were already in full action doing drawings, preparing tools etc. I felt welcome immediately and were given a workbench and a tour of Jonas impressive workshop and sawmill.

I brought several ideas for a project to build but, after seeing what the others were building, settled on a redesigned version of December Chair by Jasper Morrison & Wataru Kumano, produced by Nikkari Oy in Finland:
What I like, other than the sleek design, is that is has two special features. One is that the fabric that makes the seat is inset in a keyhole-shaped slot with a metal rod:

And also the back legs support the back rest in an interesting
joint:

Now just copying a design I feel is a bit like cheating. And this chair had a few shortcomings (probably due to the fact that is is made to be collapsible and flat pack):
- There is no support stopping the posts that hold the back rest from bending inwards. The frame is stiff enough not to break but not an optimal solution
- Only the seat is mounted in these nice slots, the back rest just threads over the posts.
Lets make that better!

Now, despite being a professional photographer, I am horrible at taking pictures in my free time. So this is a mixture of my own shop-notes-pictures and Brian´s

First a few, sketches to get the rough dimensions etc
Then a full size drawing


And ready to cut a lot of parts. Had brought some boards of hornbeam that I was fortunately enough to get from a park, Søndermarken, where I live in Copenhagen, then milled and stored for two years. Had only made small projects with it before and was curious to see how it behaved and looked. I wanted i light appearance and the hornbeam was perfect in that regard.
Hornbeam is very hard and i bit brittle so planing is a bit difficult. A bit like hard maple in that it is also diffuse-porous and super fine grained. Plane shavings look like fine lace.

While planing is difficult, turning, on the other hand, is super nice and an almost ivory like feel can be achieved. The only difficult part to turn is the back leg that needs two cylindrical and accurate parts with a straight taper in between, those needed a little extra care and frequent use of calipers.

To make the slots for the set and back rest to thread into I needed to make custom router bits, a 4 mm straight one and a 7 mm round keyhole shaped one. In my time working as a toolmaker a common type of bit for the metal mills was called a "stikkel", In english they appear to be called Single Flute Milling Cutters or D-bits.

For wood HSS steel is perfectly fine for smaller runs and the steel gets super sharp (in contrast to the usual carbide tipped bits) and Jonas had a few broken drill bits that I could use. The idea is that you take a round bar, grind away exactly half the diameter, shape the bit as desired and grind away a relief in order to establish a cutting edge. This is normally done in a specially made grinding machine with a support for the steel that can rotate in different directions. But a handheld grinding machine in a lathe works as well and
Jonas had a small hobby lathe (among several others) that I borrowed. Also found a grinding machine and here the result after a few hours of grinding away, simple and effective:
The bits got a bit blue after routing the grooves but HHS steel does not temper easily so it all worked well. The round back rest posts were routed in a v-groove support.

Jonas cozy workshop in morning light
Now next step was to drill the holes in the frame. I was so fortunate that Olav had this lovely old Arboga drill/mill machine that I could borrow. Jonas wrote a lot about that in his blog

Discussing details with Olav
Here all parts done, including the back rest support at left
And gluing it all up. It newer stops to amaze me how chair building is a lot of work on seemingly random parts, often for days - and suddenly it all just go together in a matter of minutes.

Olav had another gem as well, an old hand driven sewing machine that I borrowed. Perfect for the thick fabric (that I got from Jonas that had gotten it from a ship he worked on once)
Once I got the hang of it this machine worked like a charm, smooth and chewed through several layers of fabric. Perfect.
The length of the seat and back rest is quite critical. It needs to just exactly be able to thread into the holes  - and at the same time not be so loose that the seat meets the rails when sat on. Had to do a few test forth and back before it all worked.

The design calls for the edges of the fabric to be bent over and double at the sides. That way the diameter of the metal rod needs to be different in the ends. Found stainless steel rods at a local machinist Jonas sent me to. Made a small jig and ground away on Jonas bench grinder, rotating the rods with a handheld drill, worked just fine.

Sanded all surfaces til 400 grits and, after advice from Olav, polished the surface with plane shavings. That gave a lovely, smooth surface and decided to keep it like that. Had planned to use soap treatment and might do that if the polish does not last.

And then suddenly it was done. Jonas testing for comfort in a pile of planer shavings
At home in its final place. It sits on front of a broad bank of windows and wanted a piece that did not disturb the light from coming in. Think that works well.

Being part of DCBE was an honour, a pleasure and super fun. Being able to focus on only one thing for a whole week is such a luxury, thank you guys!

So that's it. Thank you for coming along, hope you enjoyed the read!
/Ty

Thursday, October 11, 2018

Which Chisel Set Should I Buy?

I often see this question posted in internet forums (fora?) from beginners who want to get started in woodworking and were told that they should invest in a good set of chisels that will last a lifetime. More often than not they are trying to decide between a set of eleven Lie-Nielsen knock-offs and a set of 13 plastic handled beauties they found at the home center.

I've been there, in fact I started off this way. Here is what I learned:

Nobody needs a set of thirteen bench chisels.

That's it.

I've written about  this before. I think a set of more than three chisels is a marketing gimmick (that most of us have bought into) that puts more tools than you need in your toolbox, separating you from more money that you could use for nicer tools.

Here's why:

If you have a nice box with a graduated set of chisels from 1/8" up to 1 1/2", the one you will inevitably reach for is the sharpest one. You'll eventually feel guilty about not keeping them all of them razor-sharp, but at the same time you won't have time to sharpen them all.

One doesn't often need a specific width of a bench chisel. Mortising is different, but let's put that aside for a moment. I find I use bench chisels on every project I build, but only occasionally need a specialty tool like a mortise chisel.

You can get away with two chisels: a kinda big one, and a kinda small one. My favorite sizes are a one inch chisel and a 3/8 inch chisel. These two chisels work for about 85% of all my chiselling needs.
Here's my current set of chisels in my tool chest. The ones on the left are 3/8" and 1".
The biggest advantage with starting with only two chisels is you can really learn to sharpen them. With two chisels to sharpen instead of eleven, keeping them perfectly tuned is no problem. Over time you'll get better and better at getting them sharp and in less time.

Once you are happy with those, then you can (slowly) collect some more chisels for different uses. Sometimes you need something extra narrow, or sometimes you run into a wood that needs a lower angle honed on the edge than your daily beaters. If those happen to be around and tuned up, great! However, nine times out of ten, I could have gotten by with one of my two main chisels.

I would recommend in buying a premium chisel to start with, unless someone can show you how to tune an old chisel up to perfection. I've previously recommended Lie-Nielsen chisels, and I still do. Stay away from the ones that just look like Lie-Nielsens.

As far as my own personal preferences, I have moved away from the A2 steels in my chisels in favor of older O1 steel. To me it just "feels" better. It's hard to explain otherwise.

I also like to put a new handle that I've made on chisels with unsatisfactory (or missing) chisels.
This style of handle is very comfortable in my hand, easy to make, and if it breaks I can always make another one.
I've chosen to use a different wood for each of my chisels. The one on the right was a replacement handle I had, and the next one was given to me.
With a different colored handle on each chisel, it is easy to pull the one I need right out of my chest without looking at the blade.
My chisels live here in my chest.
If you have a big set of really nice chisels, try this. Take a big one and a little one out of the box and keep them at hand. Put the rest away for one year. After a year, see if you have missed them.

What are your thoughts about the "perfect" set for the beginner?

Tuesday, October 9, 2018

The Story of the Easy Chisel Rehab

I've tortured the poor folks on Instagram with this story, so I suppose I ought to also put it up here.

I got a sweet stash of tools from Jonas' dad when I was in Denmark. They all need some rehab, some more than others.
Sweet stash of tools. The chisel I'm working on is the third tool from the right..
I got the fretsaw cleaned up and re-handled, but that's not what this post is about. Part of this haul was a few smallish chisels. For some reason all the chisels I have in Spain that are ready for rehab are around 1" wide. I thought the small ones would be usefull, too. It so happened that a 3/8" Jernbolaget chisel was exactly what I thought I needed for the next step on my rocking chair, and I don't happen to have one in my chest. Let's get this one handled up and sharpened.

I had a nice offcut of wenge left over from a Roorkee chair build a long time ago, and figured it would be perfect for this. It turns out wenge easily splits, and a tiny crack opened up after I finished the handle and drove it home.

The crack wasn't too bad. I figured I'd stuff some hide glue in there and put some massive pressure on it with a C clamp.
C clamps provide a lot of pressure.
The next day I took it out of the clamp, and figured I was golden. It looked great. All that was required now was to lap the back (which was a mess), grind the primary bevel, and hone an edge.

I took some care with all of this, and was surprised how quickly it went. However, I wasn't too happy with the edge after doing my thumbnail test. I ground it again, and honed a new edge.

My thumbnail test failed again. For some reason, I didn't trust my thumbnail test. It didn't quite work like it should, but I did everything right to put a razor edge on it, so figured I was good.

After two whacks on the chisel into wood, I discovered something very wrong, indeed.
Something very wrong, indeed.
I didn't really pay attention to the color of the chisel before. I figured it was just patina from age. But, it now occurred to me that the black-ish color of the steel combined with the crusty black flakes was a sign that this chisel has been annealed in a fire at some point.

I was trying to use a chisel that had unhardened steel. I probably could have done just as well with a chisel made from lead.
Plenty of clues this chisel had lost it's temper.
I got some great encouragement and advice on Instagram, including from Larry Williams of Old Street Tools. I watched his YouTube video and thought I'd give it a try.

I twisted the chisel out of the handle as carefully as I could. I re-opened the crack I had repaired, and opened a second crack, but they weren't catastrophic to the handle. A couple of clamps and some hide glue took care of that.
I was able to repair the handle after removing it from the soft chisel.
I don't have a forge, but The Frau is out of town, so I figured I go for heat treating this chisel using only a MAPP torch and a pair of pliers. I wasn't able to get the whole chisel glowing orange, so I just focused on the last inch or so near the business end. Once I got the little iron pools coming up, I quenched in a small jar of sunflower oil, which was the least expensive oil we happened to have in the kitchen.
This is the chisel after quenching.
Now I got the toaster oven out, and fired it up to about 400 degrees Farenheit (210 Celsius or so), and baked it for an hour. This softens the steel up a bit so it isn't quite so brittle.

While that was cooking, I removed all the squeeze-out from the chisel handle, and added a chamfer to the hole which helps the chisel seat all the way. I forgot to do this last time.
I chamfered the hole to help the chisel seat flat.
When the chisel came out of the oven, I was surprised there was even more color on it than before.
Very colorful now.
This didn't bother me, as long as the edge would hold up.

Being a small chisel, it didn't take long to lap the back, grind a 25 degree bevel, and hone it to 30 degrees.
Frickin' perfect!
Holy carp! This certainly did the trick. This chisel feels and cuts wonderfully now.
It doesn't look like much, but it sure works well.
If I had a buffing wheel, I might try to buff the black off, but I don't. I might try to polish it up at some point, but I think the color on it near the bolster will always be there. I might just leave the black on it. I will for sure leave it there for now.
Lots of colors on the metal.
I suppose the moral of the story is not to give up. If you have a chisel that has somehow lost it's temper, depending on the steel that is used it could be easily hardened again. This also might make it possible if you need to do some serious grinding, such as if you make a new side escapement plane. You can use an old iron. Just anneal it by heating it up and letting it cool naturally. You can then easily grind it to a rough shape, then harden it again.

I'll not be afraid to do this again, it was easy. But, hopefully none of my other chisels are like this.