Wednesday, October 25, 2017

Haffner KKF 15 chain mortiser

Ever since I borrowed Olav's portable chain mortiser, I have been eager to get one myself. I discovered during the initial phases of the small barn build, that I really enjoy timber framing.
There aren't many used portable chain mortisers offered for sale in Denmark, and the idea of forking out $2400 for a new Festool or $4000 for  a new Mafell is out of the question. Even I have to be realistic once in a while.

I have regularly checked the various classified home pages in Denmark, and one day while looking, I spotted something on a stationary mortiser that made me take a closer look.
In addition to the lever type handle, this chain mortiser also had two smaller handles. Now those would only make sense if the machine could be used as a portable unit.
I enlarged the pictures and could see that part of it looked like aluminium castings and not cast iron. I also managed to decipher the designation of the machine which is cast into the front cover: KKF 15

A quick search and I found a page from an old catalogue that listed the features of the machine. To me the most interesting thing was that it could be used as either a wall mounted or a portable machine.

Whenever I find a machine that I would like, chances are that it is situated far from where I live, but this machine was being sold just 20 miles from our place. So I arranged with the boys that we would drive down and get it, Gustav had to be picked up at the train station after a trip to Copenhagen with his class, so first I picked him up, and then went for the machine

Originally I had intended to do a bit of haggling just as a principle, and my argument for a lower price would be that there was only one chain , and it even needed sharpening. It turned out that the chain mounted on the mortiser was in excellent condition, and besides there were two brand new chains to go along with it as well. Knowing that a new chain can easily reach 200$ on its own it seemed pointless to haggle, so I paid the guy the  $200 he was asking for the machine and he helped me load it in the back of the car.

Once home, I checked the machine, and it was in much better condition than I could have hoped for. I tested it on some pieces of scrap, and it is a joy to use.
The only problem is that even though it can be used as a portable chain mortiser, it is designed to work like that in another way than the one that I borrowed from Olav.

Olavs chain mortiser is a 100% portable machine. It is designed to work with the chain running along the grain, and it has got a clamping fixture that is perfect. Once the machine is clamped, you can slide the sword lengthwise, and make a nice long mortise that is only the thickness of the chain wide.

My machine is heavier and works across the grain when used as a hand held mortiser. That means that the width of my mortises are limited by the width of the sword and chain combined. The good thing is that You don't have to clamp the machine to the work piece. The action of the chain will ensure that it packs the fence close to the work piece all the time.
Now if I only made one size of tenons that would be OK, but I would like to be able to use the machine on different sizes of timber, so I have to figure out a way to make a clamping fixture so my machine can also work like Olavs.
A good thing about the current set up is that it is perfect for making mortises in e.g. work bench tops. Because it only requires one flat face to register to in order to make a mortise. So I don't have to invent a longer clamping fixture to span across the width of a work bench top just to make the mortises for the legs.

I guess I should make a workbench just to use the new machine..

Haffner KKF chain mortiser mounted on a stand.

Chain mechanism.

Plunged into an imaginary piece of wood.




8 comments:

  1. Very cool, good find!
    I never used one, but Ive seen them in action. They work amazingly fast. That would b a good addition to your timber hose build.

    Bob, who also seen antique machine with a solitary chisel bit (like a pigsticker) that you plunge into the wood with a long handle, work amazingly good

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    1. Hi Bob
      Thanks.
      When I borrowed Olavs it sure speeded up the process of making all those mortises in the timber frame parts.
      I have started building another sawbench, and I used the chain mortiser for the mortises in the legs, and it works really well.

      I think I have seen Roy Underhill use one of those chisel type mortisers that you mention. He used it for making a window as I remember. A really cool tool indeed.

      Brgds
      Jonas

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  2. Jonas,

    I agree with Bob, good find. I've not only never used one but have never seen one in action. I'm looking forward to a post on it in use.

    ken

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    1. Hi Ken
      Thanks.
      I will have to get Gustav to shoot a video of me using the machine. But so far I need to complete the small barn before I start any other timber frame projects, though a workbench couldn't hurt anyone..

      Brgds
      Jonas

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  3. Cool! I built my Roubo at a class with Christopher Schwarz. Dictum thought they would help by gluing up all of the oak beams into bench tops before the class, which was nice only the plan was to saw out the mortises before laminating the beams for the tops. We wound up using a chain mortiser to make all of the mortises in those 14 cm thick oak bench tops. We never would have finished any benches without it. I also used it to make a mortise for my planing stop. It worked brilliantly for that.

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    1. Hi Brian
      Given that this machine works across the grain when used as a portable unit, I think that I could do a set of mortises for a workbench top pretty easy after the top was glued up. I guess I should try that, to see if I am correct :-)
      But I need to make a fence for the portable setup first. I guess it has gone missing sometime in the 30-40 years since the machine was built (just my guess of age)
      Brgds
      Jonas

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  4. I used to make my living by using a Makita portable chain mortiser. As you point out, the chain cut along the grain. This design works well since only the bottom of the mortise needs accuracy. I don't know what any advantage might be to orienting the chain to crosscut. I look forward to your posting more about this machine and how it works for you.

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    1. Hi Potomacker
      I think that the advantage of cross grain orientation is that you can take a "bigger bite" easy, and you don't have to clamp the mortiser to the workpiece.
      The action of the chain will pull the machine towards the fence, so the fence will only have to register on one flat surface. So moving the machine between mortises is incredibly fast. The downside is that all the mortises are the same width - and the bottom of them are rounded.
      I personally think that the Makita type and also the old Elu that I borrowed from Olav are a more versatile.
      The Makita is not sold in Denmark, and Festool and Mafell are both cross grain models.
      But I might be able to make some sort of clamping fixture that will allow me to transform the Haffner into an "along the grain model".
      Brgds
      Jonas

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