Rainy day stool

[Larry]

 I decided a few months ago to build a perch stool that was designed by master chair makers Peter Galbert, Curtis Buchanan, and Galen Cranz. There goal was to make a stool that keeps the spine in perfect alignment when seated. To accomplish this, the seat pitches forward at about a 10 degree angle. One stool leg is substantially shorter than the other two. A lot of craftsman have spoken highly of the design. I'll reserve comment until I use it for a while. If anybody is interested Peter Galbert put the plans on his blog right here.


http://chairnotes.blogspot.com/search/label/perch


The stool has been a rainy day project for me and I finally got it finished today. I only took a few pictures during the build.




I designed and built a vacuum clamp assembly a long time ago using a Wilton Power Arm so I can easily rotate my work while carving.




Drying the tapered leg tenons in my heated sand pot to less than 4% moisture content.  The tenons swell once installed in the seat.  I use hide glue for glue up because it is super easy to clean up and reversible if a repair is needed at a later date.



Final shaping of the seat after assembly. 







The tilt of the seat doesn't show well in the pictures, but in person its quite pronounced.  

[doc henderson]

great work Larry.

[customsawyer]

Fine craftsmanship.

[Jeff]

I want to sit on it!   

[metalspinner]

Beautiful!

[Andries]

I'd like to master a rain day project like that. Beautiful work!

[WDH]

Awe inspiring. 

[kelLOGg]

Stunning workmanship!!!

[21incher]

Beautiful and looks comfortable. smiley_clapping  Thanks  for sharing. 

[Walnut Beast]

As always Larry! Simply beautiful! 

[kantuckid]

Great job! 8) coming from a guy that's made lots of stools but never that one.

 My favorite drawknife is close to the one I see in the pic. It came from my Grandad & Ozarks area where he came from. Mine has original walnut handles and seriously good steel and same design as yours me thinks? Handle tangs have bottom copper washers riveted steel with brass upper bolsters. 

FWIW: As I type I'm using what's called a "lumbar roll" behind my screwed up/worn out, well abused lumbar. The stool forced posture helps but nothing like this roll pillow. 
My most recent stools are the more rectangular curved top versions. I'm not sure what you call them but they are wide butt wise, not so deep thus they don't stick out into the room too far. They fit my grandaughters little tushes well. 

I just google searched stools and saw some sculpted top, imported stools for sale that caught my eye: take a look/see @ www.josh&main.com under header "accent & vanity stools" .

[Dan_Shade]

Did you cut tapers on the legs /seat joint? 

I really like that stool. 

[doc henderson]

Hey Larry, can you tell us more and share pics of how the vacuum clamp is set up and works.  I am planning a clamp using a pneumatic cylinder to hold live edge charcuterie boards on edge to peel bark.

[WDH]

I have renamed you "Stool Man". 

[Larry]

Thanks for all the nice complements.......except for WDH, I'm not sure about being the "stool man". :D

Dan, I do put tapers on the legs.  Here is the process.

Drill seat holes with ¾" forstner bit, ream hole to a 6 degree taper with my home made reamer, and rough turn the leg on the lathe. I than dry the leg tenon to less than 4 percent moisture content in a heated sand pot. Usually takes a day or two to go from 10 to less than 4 percent. I than put the leg back on the lathe and turn the tenon to perfectly fit my tapered hole in the seat.


My process has been evolving over the last year to improve production. Pictures may not exactly match what I'm doing today, but the principle has not changed.




This is my home made reamer.  The block on the right was reamed than sawed apart to serve as a gauge when I turn the tenon.



Reaming the hole to a taper.



Fitting the tapered leg tenon to the reamed seat hole.

Ok doc your turn, a few more pictures may explain the vacuum clamp.



On the left is a pneumatic switch which shuts off controls the vacuum from my pump.  The green thing is a Wilton Power Arm which is basically a ball swivel.



The green gasket is home made from corn starch and silicon caulk.






A couple of pictures of clamping a board similar to what you would do with a charcuterie board. 

Full disclosure.  I'm a scrounge, that Wilton Power Arm is $500, the pneumatic switch is probably $50.  I might have $20 in the whole setup.

Another option.  I have a whole slew of vacuum clamps that are a block of wood with a gasket of vinyl shelf paper from Lowes, a air quick connect threaded into the wood, and a pneumatic switch made from air blow gun.  They work great.




A little on the engineering side.  Its normal for me to pull 20-24 inches of vacuum.  As a rule of thump psi is equal to half of the inches of vacuum.  So, if you have 100 square inches the holding pressure on the charcuterie board should be a 1,000 pounds.

I made one of those clamps for a friend that is cranking out charcuterie boards by the truck load (small) and he loves it for holding the board to knock off the bark.  He also uses it sometimes to ROS after the widebelt if required.

[Dan_Shade]

Thanks, is your reamer 6 degrees from the axis or 3 degrees?

What kind of wood did you use? 

I have a reamer from Lee valley, but it's pretty steep. 

[doc henderson]

thanks for the tech. info and examples of uses or what we can refer to as a "stool sample"   ;)      8)   .  do you have a reserve tank for vacuum or just use the pump?  I have my dad's old ac pump.  do you just let it run?

[WDH]

Stoolman, I meant that in the kindest possible way. 

[Larry]

Dan, my first reamer was 6 degrees, than I made a second at 3 degrees.  Last was the Lee Valley 6 degree so I could use it in my cordless drill.  After using all three I've decided I like the 3 degree reamer the best.  It removes the least amount of wood so it is easier/faster than the other two.  I think it might be slightly more accurate also.

Not really a big difference between all three of my reamers.

I made the first two reamers from osage orange.  Use it for a lot of my shop made tools.

Doc, my pump runs continuous whether I use a tank or not.  The advantage of using a tank is when you turn the vacuum switch on, it will suck down the part instantly where without a tank it takes a few seconds.

I used a large old fire extinguisher bottle for my tank.

[doc henderson]

Larry I think the question about the angle is, is it 6° on one edge (12° total) relative to the midline or 6 ° total for the whole tool side to side?

[kantuckid]

The tapers & sand process begs a comparison to the old timers who used greener wood in chair or stool posts, combined with dry rungs? But we all know they were working with the wood they had, often not KD. 
Aside from making chairs & stools, I've repaired quite a few old chairs that had no glue nor taper but broken rungs from use & abuse. This had me removing the rung remnants which were locked/held by use of wood moisture content and drilling part ways into an adjacent rung thus a mechanical lock. 
Lazy me, I'll stick with modern glues and wood wedges. I've considered a reverse taper which allowed the wedge to fill the tapered area near the surface of a stool top, chair arm, etc. but neither have i seen one I made loosen using a wedge & glue.
 Aliphatic glues will release @ ~200F which is sure not as handy as hide glue but still possible. 

Larry: Seriously neat use of vacuum technology! 

[Larry]

The tapers & sand process begs a comparison to the old timers who used greener wood in chair or stool posts, combined with dry rungs? But we all know they were working with the wood they had, often not KD.

Curtis Buchanan is the grand master of green wood chairs.  Lots of people are learning how to make it work.

I've met a couple of local woodworkers better than me making green wood chairs.  At first they wanted fresh logs from me so they could rive all the parts themselves.  They said it was hard to find thick enough wood for chair parts and when they did find wood it had too much grain run out.  I showed them I could use the sawmill to skin the logs than split them on the pit.  Makes riving a lot easier.  Sometimes I just saw bolts for them taking care to keep grain run out to zero.  They think I'm a wizard!
 
I've been working with air dry wood and would never go with KD.