June/ July Chair Build

Well as Brian has said many a time, "Life happens".  Such is the case with me.  I did manage to get a chance to finish carving the spindles for my chair last Saturday.  Before I did that I took a few minutes to sharpen my drawknives.  While the edges felt sharp and would grab a finger nail, I could tell by the way they were cutting it was time for a quick tune-up.

Bevel down knife and the Drawsharp

Pete Galbert in conjunction with Jameel Abraham of Benchcrafted fame, developed the Drawsharp.  It is a wonderful tool for quickly sharpening/honing the edge of a drawknife.  Check it out here on the Benchcrafted site and on Pete's blog.

I was able to get the spindles roughed out into octagonal shapes and set aside to begin to dry.  I let them sit for a bit before exposing them to the heat in the attic, my present day kiln that only works in the summer months.  This keeps the pieces from warping and splitting.  I was curious so tonight I checked an extra spindles moisture content and was happy to see it had gone form 35% to 15% since Saturday.  Now I cam put them in the attic to begin super drying them.

Spindle at 15% EMC.  Time to put in the attic.

I finished the night off by doing a bit of redesigning of a stool seat.  What I did was increase the size by 10% and changed a few sight line, rake and splay angles.  Nothing drastic from the original design, but it is something that I have been wanting to do and now that I have someone wanting a stool I have the opportunity.

In shop design session.

Next I will be finishing up the arm for the chair and preparing to do the final assembly.  Hopefully the sun will come out and heat up the attic so that I may finish up the June Chair Build by the end of next week.  If not I may just have to finally break down and build a kiln.  Until the next time be well and be safe.

~ Ray Schwanenberger

Chair Build Days 4 and 5

Much has taken place in the shop since the last post two days ago.  Yesterday, I pulled another piece from the water and was quite pleased to see a 39% MC reading.  This meant it was time to steam and bend.

After soaking for about two and a half days.

First I had to do a little adaptation to my steam delivery system.  Up until yesterday I had used the 12' hose connecting to special fittings on both the steamer and steam box.  The problem is 12' of hose is 9' too much.  In the past I was unable to get my steambox up to 212 degrees, and I believe it was because of a heat loss in the hose.

Wallpaper steamer requires the fitting on the hose.

Hose fitting to connect the hose to the wallpaper steamer.

 After lopping of 9' of hose I was left with 3' of useable hose with a fitting on one end and open hose on the other.  What I discovered was a 3/8" ID hose inside of the black exterior hose.

Black hose acts as an insulator around the white hose that carries the steam.

 Next I removed the brass fitting from the steam box and on the drill press bore a 7/8" hole that provided a tight fit for the black exterior hose.

Brass fitting was required when using the hose as it came from the manufacturer.

While the steamer was bringing the temperature up in the box, I carved a piece into a 7/8" round bow. I marked the center with a line and an arrow so that I would know what side to put up.  It is best to figure this out before you have a very hot piece of wood in your hands that needs bent in 45 seconds. I mark the wood in such a way that the tangential plane is against the form.  The tangential plane is parallel to the bark and the radial plane runs from the pith to the bark.  This would mean the growth rings would be parallel to the bending form.  I am happy to report that my steam box made it to 212 degrees with ease.

The steam box actually held 212 degrees without a problem

  

The bow was in the box and the timer set for 1 hour.  When working with green wood I will usually steam pieces for 30 minutes.  Since I was working with wood that had been air-dried I rehydrated the pieces and doubled the steaming time, as suggested by Pete in his book Chairmaker's Notebook. While the steaming was taking place I prepared for the bending.  As I said before, once the piece comes out of the box you have a short bit of time to wedge the piece at its center point (arrow up facing the form), bend, pin and wedge the the ends before it cools too much.  When the hour was up I put the bow in the form and bent away.  I was so so happy with the results. It bent like I had just taken the piece out of a freshly cut tree.

The only place where a fiber or two raised , SUCCESS!

 
I attribute the success of the bend to being able to rehydrate the material and being able to deliver a consistent flow of 212 degree steam through out the steam box while using a defect free piece of oak. I was so psyched with the results I carved two more bows and put them into the steam box for an hour.  Well it would be great if I reported only my successes, but that isn't me.

The other two bows came from pieces whose grain was not as straight as it should be (understatement of the week) and as a result I ended up with a few small delaminations.  I was able to use some polyurethane glue and tape to repair those.  This morning I steamed and bent two arms that I carved and they were out of some wood that I most likely should have cut short of the wonky grain and used for spindles.  However I had to give it a go (I need help). One of the arms suffered major delaminations and required glue, clamps and then tape.  At this point this arm has become an experiment.  The other arm fared a bit better but I will most likely burn it also.  It is said that a picture is worth a thousand words, well here you go.

Delamination in the bow caused a kink most likely rendering it unusable.  There is some extra material on the bow, therefore if I am able to fare the curve without loosing to much material it will be used.

This is the repaired delamination that caused the kink.

This arm bent the best but the wonky grained prevented me from being able to keep it flat in the form.  As part of my experimentation I have clamped it to my bench top with holdfasts to see if it will set in a flatter profile.

Moral of the post: If you find yourself wanting to bend pieces like these DON'T!  Seek help!

Five bends with one for sure usable bow and four ahhh maybe's.  I guess we will see how or if I am able to recover.

When the day ends it is time for the clean up crew.  My grandson Zane telling me "I help Pappy".

I have an arm that I had bent earlier so I am good to go there.  I usually bend more than one component just in case, and it appears it was a good thing.  Next I will be carving the spindles and then setting them aside to dry with the bendings from this past session.  Until the next time may you be blessed with straight grain always.

~ Ray Schwanenberger

Chair Build Day 1

Well as you might imagine getting around in the shop with a large medical boot brace on ones foot is cumbersome.  However, I must press on.  Usually I would split, rive and shave my arm and bow parts first. Followed by a good steaming then bending them in their appropriate forms and setting them aside to dry.  Then I would move onto the other greenwood work, the spindles.  But as I said in a previous post I am going to be doing things a bit out of order, due to my aforementioned state of gimpiness.  I am attempting to recruit a strong young person to split that big ole oak log for me.  So far no luck.

So I started on the seat blank.  I laid it out, drilled my center spindle hole and the four leg holes.  I then began to carve the bowl of the seat.  I am happy to report that the Sugar Pine carves very nicely. Like its cousin Eastern White Pine it requires sharp tools.  I started with my adze made by Tim Manney.  It works so nicely and made very short work of removing the bulk of the seat bowl.  I am a novice with this type of adze and am still learning the nuances of the tool.  Next I moved onto the scorp/inshave. Taking a skewed cut working downhill while paying close attention to the grain is paramount.  The wood will let you know how it wants to be carved.  It is very important to heed its warnings so as to avoid tearing out a deep hole that will be difficult to remove.  The last step was to move to my travisher made by Claire Minihan.  The travisher is a bit of a peculiar tool to learn to use, for me at least it felt a bit counter intuitive.  Again I used a skewed cut working downhill paying attention to what the wood would allow me to do.  Using my bandsaw I cut out the front of the seat in preparation to carve it.

Tools Left to Right: Adze, Travisher, Scorp/Inshave

Next I drilled the arm post holes.  To do this I used a square, bevel square and mirror to obtain my 17 degree angle along the sight line.  The mirror allows me to compare my drill bit to the bevel square with a glance rather than having to move my head around causing me to loose alignment with the sight line. I use a square lined up perpendicular to the sightline to help me stay aligned as close as possible to the sightline.

After drilling both arm post holes I turned the bamboo style arm posts on the lathe.  I do this before reaming because I want to assign and fit an arm post to a particular mortise during the reaming process.  The arm post will be marked for its particular mortise and that is where it will reside for the remainder of its days.

Bamboo Style Arm Post

   
Next I ream the arm post holes and make them into tapered mortises.  As when drilling, I use a square, bevel square and mirror when reaming.  My reamer has a 6 degree included angle, therefore I set the angle to 14 degrees, three degrees less than the 17 degrees used to drill the holes.  I align the blade of the square with the sightline and compare the top tip of the reamer with the blade of the square.  If it lines up with the edge of the blade, I'm spot on.  If the tip is left I must take more off the right side of the mortise and vise versa if the tip is right.

Reamer is in line with the sightline

 
Next I brought the bevel square up to the reamer and observed the gap between the blade of the bevel square and the tapered surface of the reamer.  If the gap is the same up and down the reamer, I'm spot on.  If the gap is larger at the top I need to take more off the mortise toward the square and vise versa if the gap is larger at the bottom.

Reamer is at the correct angle

So after reaming both mortises to the indicated correct angles one might think that it is a completed task.  Oh contraire!  What I have neglected to explain is that I actually don't ream the mortises to their final depth until after I check to see that both arm posts are in the same plane.  I feel this is one of the most critical stages of building an armchair.  If the arm posts are not in the same plane it will make it hard to get the arm to sit correctly at a later stage in the process.

Winding Sticks to check the plane of the arm posts

Even though everything appeared to be correct, a pair of winding sticks would let me know just how close or far off  I was.  At first check I was off a wee bit and it was close enough that a very minor adjustment, a half turn of the reamer to the left arm post mortise, was all it took to be nuts on.

The gap at the left is ever so slightly larger than at the right.  When the gap is even everything is copasetic.

Well that was all my foot could handle for the day.  Next I will be turning the legs and stretchers for the undercarriage.  All the while I will be attempting to recruit some help with getting that oak split.  

~ Ray Schwanenberger

Drawknife Rehab - The Conclusion

It has taken a bit longer than expected, as usual, to complete the rehab.  However, after a few minor bumps in the road, it is done!  In the last episode I left off needing to hone an edge on the newly ground bevel.  So with great anticipation I went to the drawer that holds my new Galbert Drawsharp.  Are you are asking yourself; "What is this new fangled contraption of which he speaks"?

It is a wonderful tool for sharpening/honing drawknives.  It is the brain child of Chairmaker, instructor, raiser of goats and all around nice guy, Peter Galbert in collaboration with tool maker, artisan and all around nice guy Jamel Abraham of Benchcrafted.  Ok enough of the Bromance.  Check out the Drawsharp here.

Following the instructions I set the Drawsharp to hone the newly ground edge.  I started by making several passes with the diamond abrasive on the beveled edge until a burr was turned along the entire edge.  I then flipped the drawknife over and honed the back turning the burr back to the bevel side.  This left me with an even scratch pattern along both sides of the edge.

When using the Drawsharp you hold the drawknife as though it were a fiddle and move it over the blade.  Next, I turned the pads to the sandpaper sides and continued to turn the burr from bevel to back and back to bevel using a diminishing number of strokes until the burr had disappeared.

I have heard it said many a time, if a drawknife can cut Eastern White Pine end grain and leave it silky smooth, it is truly sharp.  Well, I am short on EWP.  However, I have a plenty of Sugar Pine.  Sugar Pine is a bit harder and more dense than EWP, but only slightly.  So without any handles I put the edge to the pine.  Not the results I was hoping for.

As you can see the cut bore evidence of fine nicks in the edge.  I retrieved my jewelers loop to closely inspect the edge.  As I feared and suspected, the pitting on the back was not going to allow me to produce a keen edge.

This meant one of two things, either scrap the project here and now or attempt to remove the pitting from the back.  I don't know about you, but at times like these I hear voices; in an English accent I hear "What the bloody hell, get to work".  It might be a dead relative?  So it was, I took a file and worked the back of the drawknife, taking care to keep it as flat as humanly possible.  After removing about 1/4" to 3/8" of the pitting back from the edge I put the drawknife to a series of water stones stopping at 8000 grit.

 I repeated the honing process with the drawsharp and the final results were this.

As you can see there is still evidence of a tiny nick caused by the pitting.  I looked with the loop again and found it to be close to the end of the blade.  It was a go for the handles.  I thought about using paduck or purple heart but decided on good old cherry.  Why?  J.W. Mix & Co. was the maker of the drawknife and my research revealed the company was in New Haven, CT.  I felt it was only fitting to use a beautiful American hardwood on this old American drawknife.  I remembered my brother-in-law giving me some old cherry sticks that he salvaged out of a 19th century home, so I went digging.

This was my step drilling gauge for each handle and the handle pattern.  Each handle needed to be step drilled to accommodate the handle tangs that transition from rectilinear to round.

Now let it be known far and wide, I am not a woodturner.  I would someday like to be very proficient, that being said, this process took me probably three times as long as someone who knows what the heck they are doing would have taken.  Whew, that felt good to get that off my chest.  First I roughed out the cylinders then I step drilled each one.

Next I put the blanks between centers and began shaping the handles.  This process was much like turning legs for chairs, only smaller.  I was feeling my oats and thought I would use a skew chisel to give it that extra nice touch.

As you can see, I was humbled and put the skew away for yet another day.

Here are the finished handles drying.  The three dark rings were scribed with a skew and then burnt in with an old guitar G-String.  The finish is shellac put on while spinning on the lathe, then burnished with shavings.  After that, I wiped on several coats of an oil varnish mix.  The only thing left was to put the handles on the drawknife.

First I annealed the tang ends by heating them to a cherry red and letting them cool.  This made it easy to peen them over.  Thanks for the heads up Pete.  I really, really like the look of natural cherry and black together so I decided to paint the ferrule's and caps black.

A drawknife that could have easily been destined to be on the wall at a Cracker Barrel will now be residing on the wall above my bench waiting to be put into service.

With every project I try to learn something.  I take away from this project; The importance of finding edge tools that are free of or have very little pitting; That some tools are worth the extra effort to make them usable again; That investing my money in good tools made by good people is worth 10 fold the expenditure; That investing some time in learning to use a skew chisel would be a wise investment.

I hope that I have been able to provide you with some good information.  Information that will encourage you to get into your shop and try something new.  This is how we learn, by pushing ourselves outside of our comfort zone.  So let's go to the shop and do something new and exciting, and always be safe.

~ Ray Schwanenberger

Drawknife Rehab - Part 4

Yesterday my day began a little before sunrise with a trip to my good friend Ralph's farm in the flat lands of eastern Indiana to pick up a little hard maple.  It was a beautiful drive with the fresh snow on everything and as the sun came up revealing a crystal blue sky.  After I got a close look at the pieces I think I may have some figured maple on my hands.  These are not ideal for leg blanks for my windsor chairs but I think I will be able to use them for another project.  That of course will be another post.

After an equally beautiful trip home I parked the truck and headed into the shop.  It was time to get back to rehabbing my old drawknife.  This next step, grinding the blade to remove the chip/nick, was the one that was going to determine if this was the end of the trail for this project or if I was going to be able to continue and make this a usable drawknife.

I had several concerns moving forward.  The one concern that loomed greatly in the back of my mind was a matter I had never considered or heard of, until Paul Frederick brought it to my attention in a comment. Hydrogen Embrittlement.  My understanding of hydrogen embrittlement is that atoms of hydrogen are absorbed into the steels atomic lattice like structure which causes the steel to become brittle.  Hydrogen embrittlement may have occurred to some extent because I removed the rust using electrolysis.

Michael Olsen is an electrical engineer that read the post and left this comment:  "I would be skeptical of embrittlement considering the relatively low energy levels used.  Most such brittleness occurs in either high voltage electrolysis of thicker material or combined low voltage and thin sheeting".  Michael gave a very interesting and more in depth explanation in his comment that helped put my mind at ease.

Further research revealed that the passage of time, letting the piece sit for an undetermined amount of time, or baking the piece at 200 degrees Celsius (392 degrees F) for four hours, would cause the hydrogen to be dislodged from the steel.  Since the knife sat over the Holidays it was off to the grinder.

In the picture above is the jig I use for grinding drawknives.  This jig is one that came from the wonderful mind of Pete Galbert.  If you are interested in building this wonderful jig and learn how to use it check it out here.  There is no need for me to try to explain what Pete has already done so well.  The first thing I had to do was to prep the spine of the drawknife.  I filed, sanded, and waxed the spine to ensure that it would slide easily over the hardened steel pins of the jig.  As a side note, since I do not have a designated spot in my small shop to work on metal, I take great care to shop vac, often, the metal filings so that I do not discover them in a future woodworking project.

After preparing the spine I adjusted the jig so that the wheel would be grinding in the middle of the existing bevel.  I measured this to be roughly 25 degrees.  I used no real forward pressure on the knife just enough to keep it in contact with the stone without jumping, and moved the knife back and forth across the spinning stone.  I do use a slow speed grinder.  While I was making progress it was taking quite a long time to get down to the bottom of the chip/nick.  So I decided to employ a method I have used on nicked plane irons in the past.

I used a set of dividers to gauge the distance from the spine to just at the bottom of the nick and scribed a line onto the newly ground bevel.  I then marked the metal that was to be removed with a red Sharpie.  Here is where the process goes against everything that seems correct.  I laid the flat back of the knife onto a grinder table and ground the edge of the knife to the scribe mark.  Zip-A-Dee-Do-Dah and Bob's your uncle, no more chip/nick.  Now what remained was a relatively large flat where a sharp edge is supposed to be.  I highlighted it in red so it would be easier to see.  Now it was back to grinding using the grinding jig.

With a little more time I was able to grind a nice even bevel across the knife and it is now ready for honing.  I was so excited to be able to reach this point of the restoration without the drawknife cracking due to possible hydrogen embrittlement and to discover, at least at this point, it appears the pitting that remains is not deep enough to prevent me from obtaining a good edge.  However, this will only be fully realized when I finish honing.  I was so pumped up over the results I broke out all of my old drawknives that needed to have the bevels reground and went to work.  In a matter of thirty minutes I was done.

The next thing that needed to be done was to make the angle of the handle tangs as close as possible to the same in a position that was comfortable to me.  It turned out to be just about 83 degrees.  I was able to accomplish this very easily without heating the steel.  I clamped the tang up to the bend in my leg vise and ever so gently moved the blade to obtain the desired angle.  I then ensured that the tangs were in line with the back of the blade.

What determines if a drawknife is bevel up or bevel down?  If the handles are in line with the back of the spine it is a bevel down knife.  When in use with the bevel down the hands and wrists will be comfortably in a downward position.  It is not very comfortable, nor is it recommended, to use a drawknife with the wrists cocked upward in an unnatural position.  By laying the knife on its back and then on its bevel, it readily becomes evident as to which way the drawknife is to be used.

In the next exciting episode of Drawknife Rehab, I will be posting on honing the edge, starring the amazing Galbert Drawsharp. If all goes as planned, I will be including the turning and installation of the handles.  So stay tuned for the next exciting episode of Drawknife Rehab.  Yeah I know, my bubble is a bit off.

~ Ray Schwanenberger