Tuesday, April 26, 2011

Micro Adjustable Grinding Jig

Today I finally got to spend a whole, uninterrupted day working in my new shop. It was fantastic! I've been looking forward to resuming shop life and I made sure to mix up activities to get all the juices flowing. In the morning, I assembled a continuous armchair and in the afternoon, I decided to pursue the grinding jig that Greg and I played around with at Kelly Mehlers.

 

Here is the finished jig and you can see the steps to making it below. I used spring pins for the bearing surfaces that the tool rides on. They are spring steel, so they will be hard enough to resist the wear of the tool riding back and forth without forming ruts. You can find them in the hardware store along with the bolt and locknut that form the adjuster.

To start out, I needed a dado cut across the block of cherry. Without a table saw or sliding mitre saw, I decided to pull out my trusty Stanley dovetail saw. Years ago, I filed the teeth off of this saw and refiled new ones that were a bit larger and did NOT set the teeth. Contrary to what you might expect, it doesn't bind and it cuts like a laser.
I've tried lots of the fancy saws out there, and maybe their handles are more comfortable, but none has surpassed my $10 Stanley. Don't get me wrong, I love that toolmakers are out there trying to make better quality saws, but I always feel like the teeth are too small and the set too great, but to each his own.



 I cut a center kerf and chopped out  most of the waste before bringing in my much neglected router plane (can you tell I was in the mood for fun!)




After a tiny bit of cleanup on the dado walls, I cut the sliding block that holds the pins. As you can see, I mounted some aluminum angle on both sides of the block to capture the adjuster bolt.
The notch out of the bottom of the block and the small slot out of the back serve the same purpose, namely to increase the travel past the aluminum. I suppose I could have done two notches or two dados, but I was in the zone and working on the fly.




I put the block in the slot and marked the position of the bolt, through the holes already drilled through the aluminum on both sides of the adjuster block. It's a good idea to offset the bolt hole just a hair above the holes in the aluminum to create tension against the bottom of the slot. This will create stability and help keep it from vibrating out of position.

The bolt easily cut threads through the cherry block.



Then I drilled for the pins. The vertical pin is only partially housed.






Here, you can see the horizontal pin inserted into the hole beneath the vertical. I used the grinder to trim the length of the horizontal pin afterward, and pared back the face of the block to give more clearance around the vertical pin.



Here is the whole unit clamped to the tool rest. I used the gross adjustment of the wolverine jig to start and then turned the bolt to fine tune the setting.





It's very important to note that the back of the drawknife, which rides along the pins should be filed clean and smooth. The grind will only be as straight as the the back. Luckily, most blades are soft along the back and easy to file and polish.


Here is the grind, I am very pleased. I loved being able to control the angle so precisely.



And for the farm enthusiasts out there. It's an amazing coincidence that Sue and I moved just a mile or so from a Heifer International Education Farm. We have been frequent visitor to see the births and visit their lovely herd of goats.


Here are some of their new additions. We just stand there grinning like idiots.
It seems like these kids are born knowing something important, when the sun shines on you, stop what you are doing, close your eyes and enjoy.

Thursday, April 21, 2011

A Great Resource

Since the articles in Fine Woodworking came out, I've gotten lots of inquiries about the butternut and where to get it. We in the chairmaking community are lucky to have Nick Cicchinelli thinking about our needs and working to help us out. I've bought lots of seat stock from Nick, and so has Curtis, Greg, Elia and the list goes on. He bought the Timbersmith Company from Mike Coseo about 5 years back and I have been rooting for him ever since. It's rare for someone to tune into the special needs of chairmakers and keeping his business moving forward serves us all. 

The Timbersmith
Nicholas A. Cicchinelli
302 St. Hwy. 458
St. Regis Falls, NY 12980
Phone: (315) 323-4880 ~ Fax: (315) 265-3186
Email: nicholas@cicchinelli.com 


Air dried seat blanks & planks ready to go.

Tuesday, April 19, 2011

Back in the Cauldron



I've just returned from 2 weeks at Kelly Mehler's School in Berea Kentucky, where I taught back to back fan back side chair classes with the help of Greg Pennington.  As usual, the classes proved to be fertile ground for innovating new techniques and streamlining the ones already in play.

We spent 6 days in each class making the side chair, which gave us ample time to go into depth on the fundamentals, plus address some peripheral chairmaking issues. I enjoyed the extra time and pacing of the class and I think it was also reflected in the high quality of the finished chairs. I am teaching the continuous arm in two classes this year, one at Highland Woodworking in the fall and one at North Bennet Street in the summer, and I scheduled them as 7 day classes to keep the same pace, with a slightly more complex chair.






Here is the chair that I brought as parts and assembled and painted during the course of the two classes. I know from experience, that demonstrating milk painting can save years of torment.


He is Greg demonstrating his stroke of genius with simple lasers. He uses them to help align during reaming and drilling. We gave them a try and I was very pleased with the results and possibilities.



 

There were some times where the set up seemed slower, and therefore I wouldn't say that they are always the best tool for the job, but it sure is nice when you need an easy to see reference.


This laser was self plumbing, which made set up for the vertical element super quick.

Another tool that Greg and I had time to think about was the grinding jig that I showed a while back. It's a simple notch that you cut out of a piece of hardwood and ride the back of the drawknife blade in while grinding. This is based on an idea sent to me by Steve Kinnane from North Bennet Street.


But we noticed that it would be advantageous to have a subtle adjuster for it. So Greg made this little jem with a bolt for adjusting the notch. The hardened steel pins form the notch and made the motion of the knife smoother. I am on my way to the hardware store to make my own version which I'll post in step by step detail. The students in the class used this, and the simple notch version to get near perfect results. 

I also have some ideas for making our tenon rounders easier to adjust, but more on that later.

And what would a class be without a photo of the conquering hero!


Here is Wallis from week one with his assembled chair. As usual, Kelly was a gracious host and the two weeks flew by, and now that I'm home, I have a list a mile long of moving tasks still to complete, so off I go to the DMV, ah, livin' the dream...