Frankenstanley

I've been turning a large batch of handles for the reamers that I make over the course of the past few days.  To accurately size the portion of the handle that locks into the body, I use a rounder plane like the one pictured above.  My rounder is made from a block of wood and a Stanley frog and blade assembly (á la Pete Galbert) from an old handplane.  It works great, precisely creating the joint that I need time and time again.  While this seems like an intuitive assembly to put together, it can be tricky to get it to work properly. 
The first one that I made required so much force to turn the spindle through the cutter that it tore up my hands and aggravated my forearms every time that I used it.

When cutting with gouges and skew chisels on the lathe it is important to present the edge of the cutting tool with minimal clearance of the bevel.  This ensures that you are cutting and not scraping the wood away, which tends to leave a better finished surface and reduce resistance to the forces of cutting.  The same principles apply to rounder planes.  The cutting edge should be presented to the workpiece at an angle just high enough to prevent the back of the bevel from rubbing.  In the picture below the blade has a 30 degree microbevel, which means the iron must be bedded at an angle slightly greater than 30 degrees to prevent the back of the bevel from interfering with the cutting action.  In this example the iron is bedded at 35 degrees.

Note the low clearance angle of the bevel.

The low clearance angle reduces the effort needed to cut the spindle.  If you have ever used a low angle block plane (especially on endgrain) you have probably noticed how it seems to slice through the fibers with less effort than planes with blades mounted at higher angles (typically 45 or 55 degrees).  Keeping the angle of attack as low as possible in a rounder plane translates to faster work, less effort, and forearms that won't be screaming at you when you pick up that third chair leg to cut the tapered tenon on top.

5/8" hole.

With this knowledge, the process for making a successful rounder plane is straight forward.  Start with a block of wood roughly six inches long and as wide as the blade you will be using as the cutter.  Drill a hole the size of your finished spindle or the top of your leg through your block and ream the hole to the desired profile.  My example is a 5/8" hole with a six degree taper in the first 3/4" of the hole.

Reaming taper in the first 3/4".

I do the reaming for holes like this by holding the reamer in one hand and the workpiece in the other.  The only reference you have to be sure you are going straight is that the end of the reamer coming through the hole remains centered.  I actually watch that end as I turn the reamer to make sure that I stay centered.

Reamer centered as it exits the hole.

With the hole reamed to the finished profile, remove all but the last sliver of wood above the hole.  I use a bandsaw and fence to remove the bulk of the waste.

Bulk of wood removed.

And finish by planing off the last sliver of wood until the hole just begins to show through the surface, as pictured below.

I trim the last fragments of wood from the opening with a knife or saw.  If you have ever made a wooden handplane this begins to look a bit familiar.

Place the frog on the surface of the wood.  Note that if you tilt it up so that the front portion of the frog sits level on the wooden block, the blade protrudes into the hole instead of resting at a point on the circumference of the hole.  The frog must be tilted back, which simultaneously pulls the blade up out of the hole and lowers the clearance angle, as addressed above.

Blade extending into the hole.  Frog must be tilted back.

The standard angle frog positions a plane blade at 45 degrees to the sole of the plane.  For my purposes I want the blade to be bedded at 35 degrees.  That means that I want to subtract 10 degrees from the existing 45 degree frog, to achieve my 35 degree bed angle.  To permanently adjust the bed angle add an angled riser block that tilts the frog 10 degrees back.  Cut a 10 degree wedge the same width as your frog, with a maximum thickness of about 5/8".  Smooth the top and bottom surfaces of the wedge with a handplane and position the wedge on the block underneath the frog with the blade assembly roughly centered on the opening.  To properly fit the riser block, saw off the front of the riser in 1/8" increments (or less) until the elevated machined portion of the frog sits flat on the wedge shaped riser block as pictured below.

Frog properly seated on riser block.

One clamp provides enough pressure to glue the riser block in place.

Riser block glued in place.

After the glue has set up reposition the frog on the block.  If the frog rocks back and forth, fine tune the bedding surfaces with a plane to remove the offending high spots.  With the frog solidly bedded remove the blade assembly and mark the holes to attach the frog to the block.

Holes marked for drilling.

Drill a few test holes to find the appropriate pilot hole size for the screws that originally attached the frog to the plane's sole (3/16" worked for mine).  The holes should be drilled square to the sloping surface of the riser block.  I drilled the pilot holes on the drill press by shimming underneath the block until the sloping riser block was square to the drill bit.

Pilot holes drilled.

Attach the frog to the block.

Frog in place.

My default method of problem solving is heavy on the math.  I love calculating angles and using trig functions to describe the details of what is happening on my workbench.  The first time I made I tried to walk down the geometry road to figure out the ideal shape of my blade in relation to the bedding angle.  My thoughts went something like this, "If I grind a 6 degree taper on the last 3/4" of the blade and the blade is bedded at a 35 degree angle, the assembly will actually be cutting a taper of...."  After about five minutes down that road my brain exploded and I switched to a trial and error approach to blade shape and position.  You will know if the assembly is not working right.  Try to figure out where the spindle is binding or why the blade is cutting to much.  Play around with the depth of cut adjustment, amount of skew, and blade shape.  Also, move the frog forward and back until you find a sweet spot where the assembly cuts the desired shape and the amount of force necessary to turn the wood through the cutter does not tear apart your hands and forearms.

Test piece.

For joints that have a taper and a straight section you will need to grind the blade to the appropriate profile.  For joints that are a straight taper you will have to attach the riser block at an angle (it should be half the angle of your total taper) to appropriately position the blade.

Blade with tapered and straight sections

Once the frog and blade are properly set, the rounder produces repeatable, perfect joints.  I turn my reamer handles very close to their finished size and remove just the last, little bit of material with the cutter.  This produces the cleanest results and it minimizes the wear and tear on my forearms.

Perfect joints every time.

Shaving Horse Base

The base of a shaving horse has to be solid.  I prefer a base made of a laminated beam with three legs glued and bolted in place.  It is stout and the three legs sit firmly on uneven workshop and porch floors, even outside.  The base can also be built using the same construction as a Windsor chair; a solid plank with turned legs and tapered mortise and tenons to join them.  If you have already made chairs this base is faster to build.  Jameel Abraham's shaving horse built to Peter Galbert's design is a good example of this construction.  If you choose to go this route I recommend making the leg tenons substantially beefier than chair leg tenons and starting with a plank that won't flex along its length in use.  If the plank can flex it will creak, moan, and trot across the room as you work.  Not a desirable trait for this type of horse.

For this tutorial I am building the laminated beam style base, but the clamping mechanism can just as easily be used with a plank base, or as a retrofit to an existing shaving horse.

My shaving horse.

Construction begins with a 16 foot southern yellow pine 2x10.  With thoughtful layout this is enough material for the entire shaving horse if the wood is nearly perfect.  I used to live in North Carolina and eastern Tennessee, where yellow pine lumber is cheap and abundant.  I live in Maine now and yellow pine is much harder to come by.  OSHA walkboards can be a good source of yellow pine if you live outside of the southeast and are willing to pay more than construction lumber prices for it.  The upside is that all of the walkboards that I looked at were nearly perfect.  That means no digging through the pile for that one perfect board.  The cost would be prohibitive for building something like a workbench, but when only one board is needed the walkboards fit the bill for me.  You'll have to go to a lumber supplier or quality building supply as the big box stores don't carry them.

The laminated base consists of two rails at least 3" wide and 54" long, and two spacer blocks the same width as the rails.  The rear spacer block is 6" long and the front one is 3" long.

Parts for the base.

The rear legs are 2 1/2" wide and 24" long.  They each have a 20 degree angle cut at their tops, which gives the rear legs their splay.  Lay out the angle so that the top of each leg tapers to a 1" width.  

Rear legs.

The shape of the front leg is slightly more complex.  The leg rakes forward at 25 degrees.  The front edge of the leg is 20" long.  Lay out the 25 degree angle that forms the top of the leg and the same angle that forms the bottom of the leg.  Make a mark along the angled line that forms the top of the leg 4 3/4" from the edge, and a mark on the angled line that forms the bottom that is 2" from the edge.  Connect these two marks to complete the shape of the front leg.

Front leg.

The front leg is wider at the top to allow greater offset for the two bolts that will hold it in place.  If the bolts are directly in line with each other they will provide little resistance to the racking forces on the front leg.  Like this:

The reason to glue the front leg in place and offset the bolts.

That third bolt stopped the movement, but it isn't exactly an elegant solution.

Base glue up.

Glue up the rails and the two spacer blocks.  I squared and jointed the top edges of the rails prior to glue up, but you can even things out later if you are so inclined.  The leading edge of the front spacer block should be 14" from the back edge of the front leg to provide clearance for the swing arm.  I glued the front leg in place after the spacer blocks so that I could take the time to get it aligned to my liking.

Counterbore for the bolts.

With the leg glued in place I layed out the bolt locations on both faces of the base and drilled the counterbores to house the heads and nuts of the bolts.  The hole locations are located 1" down from the top edge and 1 3/4" from the back edge of the top of the leg, and 1" up from the bottom edge and 1 1/2" from the front edge of the horse.  I drilled the counterbores to a 1/2" depth and used 4" by 3/8" bolts.  

Completing the hole by drilling through from the second side.

I drilled the through holes with a long 7/16" twist bit, from both sides.  Look close and notice the pencil lines across the top of the shaving horse.  Those are the lines that I used to carry the layout for my holes from one side of the horse to the other.  I also used them as a reference to sight the long drill bit with.  For each hole I drilled halfway through from one side, then flipped the horse around and drilled from the other side to complete the hole.  The drill bit is 1/16" larger than the bolts used and the play of the bolt in the hole usually compensates for inconsistencies in drilling.  Usually.  

There are a few of other techniques one could use to drill these through holes, either with increased visual aids for lining up the bit or using the drill press.  This technique requires no set up and it makes the whole process feel like a game to me.  I get to see how well I can line up each of the holes.  When I am building things for my shop I can take greater risks than when I am building things for a client.  I like to use these opportunities to develop my eye and my skills.  Plus, my drill press table is too flimsy to hold this much weight.

The washers for 3/8" bolts fit perfectly in 1" holes.  If there is misalignment in the bolt holes sometimes it is necessary to grind the washer or remove some wood with a gouge to get the bolt to come through the center of the washer.  Another option is to drill the counterbores at 1 1/8" to provide more play in the location of the washers.

Rear leg dado.

The rear legs fit into a 1/2" deep groove.  The front edge of the groove should be 1/4" back from the front edge of the spacer block.  The groove is raked back at an angle between 10 and 25 degrees.  The rake is just for looks, as it would be challenging to tip over backwards on this thing.  You can have more rake if you like the way it looks or less if you have Victorian moral sensibilities.  Actually, the legs on the horse that I am building are only raked back at 10 degrees.  It doesn't look quite right to my eye.  My previous horse has the legs raked back at 25 degrees, which looks like a bit too much to me.  Something in the ballpark of 15-20 degrees probably looks best.  Pictures.

10 degrees.

20 degrees.

I cut the rear leg groove with a handsaw and a router plane.  It could just as easily be cut with a saw and chisels or an electric router.  The rear legs should fit tightly in their grooves which prevent them from racking.  The grooves also help to temporarily hold the rear legs in place for drilling.

Rear leg fit up.

When you fit the rear legs in their grooves make sure that they seat all the way down and do not rock

The layout and drilling of the rear leg bolt holes is the trickiest part of getting the base together.  My advice is to do careful layout and then don't think about it too much and drill the holes.  My friend Zac Ispa-Landa recently came to build a shaving horse with me and I spent a few hours trying to dream up a new way to do this drilling that was simpler and more controlled.  All that thinking just made my head spin.

I use the square cut on the end of the legs as a reference surface for laying out the hole locations.  With the legs clamped in the angled grooves only the front inside corner of each leg will be flush with the top of the rails.  The holes are centered on the leg and 1 1/8" and 2 1/2" from the top edge on center.  These distances will change a little if you are angling the legs more than 10 degrees.  You want to end up with close to 1/2" of wood above the top edge of your hole after you  trim the tops flush with the rails.

Zac drilling the rear legs.

Before clamping the legs in place draw a square line from the center of one groove to the other to use as a sighting aid.  Clamp the legs in position leaving enough room above the clamps to drill the top holes.  For the angled counterbores I use a 1" spade bit in a cordless drill.  It is helpful to have a friend or a mirror to help align the elevation of the bit.  Use the line across the top as a sighting aid and drill in until the flat surface created by the drill bit is approximately even with the vertical plane of the outside of the rails.  Stop and check a few times until you have it.  After both counterbores are drilled use the long 7/16" bit to drill through from both sides.  If your bolt won't go through wallow out the hole with your drill bit, or anything else you can get in there until it does.  If you have a 1/2" twist bit you can also chase through the original hole with one of those to give the bolt more clearance.  If the bolt slides right through, pat yourself on the back and count your blessings.

Tighten the bolt and remove the clamps to drill the lower hole.  Follow the same process except the depth of the counterbore is 7/8" on the bottom edge of the hole.  The upper bolt is 4 1/2" long and the lower bolt is 5 1/2" long.

Legs trimmed.

Trim the tops of the legs flush with a saw and a block plane and trim the end of the beam to even it up.

With the legs assembled the base slopes forward considerably because the rear legs are overly long.  To get the base to sit properly it is necessary to level the legs.  The goal in leveling the legs is to have the tops of the rails 18" from the floor after trimming the bottoms of the legs.  My workbench isn't long enough to level the legs on, so I had to level them from the floor.   Using a tape measure or framing square and a few blocks and wedges, I leveled the base from front to back and side to side.  The measurement from the floor to the top of the rails should be the same or very close wherever you check it along its length.

After inserting blocks and wedges to level the tops of the rails, the distance from the floor to the top of the rails should be greater than 18".  For example, lets say the rails are 22" from the floor (this number is arbitrary, just for the purpose of example).  To bring the rails down to 18" from the floor I would need to lower the tops of the rails by 4" (22" minus 4" equals 18").  To do this you have to scribe a line around each of the legs 4" above the floor.  Enter simple scribing tool.

Simple scribing tool.

The scribing tool is just a block of wood with a clamp holding a pencil in place.  The pencil needs to be clamped firmly enough that it will not move.  The point of the pencil is set to the desired height, in the case of the example, 4 inches.  Then pressing the block of wood against the floor, trace around all of the legs.  When the bottoms of the legs are sawn to this line the top of the rails will sit 18" from the floor.

Base complete.

Seeing this nice clean base next to my shaving horse made me realize just how much abuse my horse has taken in the three years since I built it.  It shows wear and tear, but it still has a long life ahead of it in the workshop.  The new shaving horse is for spooncarving in my apartment in the evenings.

Chiavari Chairs

Italian chiarmakers and designers have made a huge impression on me.  Gio Ponti's Superleggera chair blew me away when I first saw pictures and read about it; light, strong, elegant, visually dynamic and simultaneously simple.  Chairs like this set the bar very high for would be chair designers.  Two winters ago I hunted down every word written about Gio Ponti in the English language, primarily through interlibrary loans.

Superleggera ad from the 50's.

Gio Ponti frequently cited the chairs of Chiavari as a significant source of inspiration for his design.  Subsequent research about Chiavari chairs yielded these two videos which I thought others might be interested in.  Don't expect drawknives and steam bending, but there are at least a million other things to learn from watching these videos over and over again.

The first is a short history of the Chiavari chair.  Watch for Franco Casoni's friendly treatment of his statue.

Fratelli Levaggi is a factory in Chiavari that makes these classic chairs.  This video details a new design.  The music makes you feel like you are on an epic adventure, which is exactly how the workshop feels when everything is going right.  Enjoy!

Taming Bandsaw Vibration

I love my bandsaw.  It is a rugged 12" Atlas with a cast iron frame and good blade guides that was made in Kalamazoo, MI in the early 1950's.  When I bought the saw a few years ago it was in rough shape, but it had good bones and an almost new 1HP Baldor motor (which alone was worth more than the asking price for the whole setup).  One of the things I like about buying vintage machinery is that in order to get it to perform well, you often have to take the whole thing apart, clean and lube it, and then put it all back together again.  The process is far from plug and play, but by the end I know the machine and all of its quirks inside and out and that base of knowledge helps me to properly tune and maintain my tools at a very high level.

My Atlas 912 bandsaw.

When I was tuning up this saw I did all of the standard things to minimize vibration.  I replaced and crowned the tires, aligned the wheels, aligned the motor pulley and drive pulley, and upgraded from a standard v-belt to a link belt.  That initial tune up got the saw into good shape and it has performed admirably for me for three years now, but it has always been a little nosier than I would like and there was a noticeable vibration in the table while the saw was running.  Every now and then I would try something small to eliminate a little more vibration and noise, always coming shy of the quiet vibration free bandsaw of my dreams.

I have known for a while that the thin sheet metal wheel covers were creating a lot of noise, so most of my vibration reducing efforts have focused on them.  Last week I finally had a the vibration destroying breakthrough that I have been seeking for the last couple of years. 

While the saw was running I placed my hand on the center of the lower wheel cover and the noise and vibration were immediately reduced.  I took my hand off.  The noise and vibration came right back.  I took off both wheel enclosures and ran the saw without them for a few minutes and it ran smooth and quiet.  It turns out, the thin sheet metal was picking up vibrations in the saw and amplifying them. 

There were two distinct sources of noise that the saw was producing which had to be addressed separately; the hum of the center of the covers and the rattle of the edges.

Tracing the covers.

The centers of the wheel covers were humming with harmonic vibration and needed something to absorb it and keep the vibration from radiating throughout the rest of the saw.  I picked up a piece of 1/2" MDF to make inserts to attach to the inside of each wheel cover to add mass and absorb the vibration.  I traced the covers and then cut out the shapes on the bandsaw.

Traced and ready to cut.

Fitting the inserts took a couple of attempts.  The corners of the sheet metal are rounded and the MDF inserts needed to be 1/2" smaller than the outer dimensions of the sheet metal to rest flat on the center of the covers.

Inserts fitted.

I used double sided tape to secure the inserts to the wheel covers.

Double sided tape.

With the inserts in place the wheel covers had a solid, reassuring weight.

Edge wrapped in vinyl tube.

Where the edges of the wheel covers meet the cast iron frame or other pieces of sheet metal they vibrate and rattle against each other.  These areas needed a barrier to prevent the two pieces of metal from contacting.  I slit a line in a roll of 1/4" vinyl tube and slipped that over the edges of the wheel covers.

Cover installed.

With the MDF inserts and the vinyl tubing installed my little bandsaw runs like a top: quieter than I could have imagined and only the slightest vibration on the table.  Simply a joy to use.

Build a Better Shaving Horse

The first woodworking I ever did was on a shaving horse.  I had just turned twenty and a twelve year old sat me down at a shaving horse and taught me how to make a spatula from a piece of red maple firewood with a drawknife.  I was hooked.  The simple elegance and intuitive feel of the shaving horse and drawknife completely drew me in.

The shaving horse.

I've had the good fortune since that day to spend many hours and days on an array of shaving horses and work with a few other shaving horse aficionados.  I want to emphasize credit to Carl Swensson for the clamping mechanism that I used on my horse.  His winter of experimentation with weights and pulleys testing the holding power of various shaving horse configurations forms the basis of my understanding of how shaving horses function.  My shaving horse draws heavily on Carl's ideas.

My horse looks similar to a traditional dumbhead style shaving horse, but the design offers increased holding power and better ergonomics than  many of the other horses that I have used.  If you have ever had the wind knocked out of you by a piece of wood slipping from the jaws and slamming into your stomach, read on!  The clamping geometry of this horse and the reduced racking of the swing arm keep your workpiece in the jaws and away from your sternum.

The horse consists of four components; the base, the platform, the swing arm, and the seat.  Dimensional southern yellow pine lumber is the material of choice for this horse.  It is rigid, relatively light, affordable, and just hard enough for all of the components.  Also if you are willing to sort through the pile, you can buy nearly perfect, knot free boards.  Medium soft hardwoods like tulip poplar would also work well.

Shaving horse base.

The base consists of two rails, three legs, and a few spacer blocks.  The front leg angles forward at 25 degrees, and the rear legs splay out 20 degrees and rake back 10 degrees.  The two rails make for a very rigid base that does not flex at all under the heaviest use. Three legged horses are stable on even the most uneven floors and outside.  The top of the rails are 18 1/4" from the floor.

Rear leg detail.

The rear legs are rabbeted into the rails and bolted in place to form the back of the horse.  I unwisely use this section  as a sometimes chopping block when I am lacking something more suitable.  My shaving horse is always nearby.

The business end.

Wedged tenon.

The working platform is secured to the base by an integral tenon that is secured with a wedge from the bottom.  This allows the whole horse to be disassembled in a few minutes for easy transport in the back of my small pickup.  The front edge of the working surface is 10 inches from the top of the base rails and the platform is angled at 7 1/2 degrees.  This arrangement works well for my body.  I am 5'5". For ergonomics your shaving horse should have the platform at a height and angle that puts your forearms in a straight line with the piece of wood being held in the horse's jaws.

Forearms form a straight line that is continuous with the workpiece.

Look at the picture above.  Now, imagine that the work surface were five inches lower.  In order to keep my forearms in line with the workpiece the angle of the work surface would have to be sloped to a greater degree.  If the work surface were raised it would have to be less tilted to maintain the proper relationship.  The platform height and angle are easy to mock up if you have a mirror, camera, or friend to check your forearm alignment.  When mocking up the platform height, use a piece of wood of a thickness that you will commonly be shaving.  Most of my shaving is done with pieces that are close to one inch in thickness.

More than a 15 degree work platform slope starts to feel awkward to me and greater angles also reduce the gripping power of the jaws.  For an arrangement of optimal holding power the platform should be parallel with the jaw of your horse.  In fact, if I were making this horse again I would either make the platform parallel to the rails, or angle the head of my swing arm to match the slope of the platform.

Laminated platform assembly.

The base of the platform is a three part lamination.  The longer center piece, which forms the integral tenon, has a mortise angled at three degrees that locks the assembly in place on the base.  The center lamination also has a low angle cutaway at the top to allow the swing arm to pivot all the way forward.  The two outer laminations form the giant tenon cheeks and are pulled tight against the rails of the base when the wedge is driven into the tenon.  The outer laminations also form the channel that the swing arm assembly travels in.  The swing arm is planed to fit this channel with minimal slop.  A nice fit here prevents the swing arm from racking to the left or right when a piece of wood is under only one side of the jaw.

Notice the orientation of the growth rings on the outer laminations.  The pieces are oriented so that they cup away from the swing arm.  If the wide boards cup (which they will) and they are oriented with the pith side of the board to the outside of the lamination they will pinch the swing arm and prevent it from swinging.  No fun at all.

Some shaving horse users like to leave their horses outside in the rain and snow.  The tighter tolerances of this horse will not fair so well in those conditions.  This is an inside horse when the weather turns foul.  Repeated soaking and drying will make the fit of the swing arm sloppy and increase the racking of the head from side to side.  The more the head racks when you press on the treadle, the harder you have to push to hold your workpiece securely.

Swing arm and treadle.

Adjustment holes and groove.

The most notable feature of the swing arm is the groove that the holes for the pivot pin lie in.  This groove is one of the biggest improvements over the arrangement in the basic dumbhead style horse that many people use.  As you draw the pin from the hole to adjust the height of the head, the pin remains in the groove which keeps it in line with all of the other holes.  This makes it a simple matter to slide the pin in the next hole and adjust the head up and down.

Shaving horses have better holding power the closer the height of the head is adjusted to the workpiece.  For the greatest power, the head should be in the lowest position that the thickness of the workpiece allows.  Simplifying the pin mechanism encourages more frequent adjustment of the head.

Adjusting the head.

For the greatest possible holding power the front edge of the head, which actually grips the stock, should be directly in line with the pivot pin holes in the swing arm.  For a dumbhead style shaving horse this is not exactly a practical arrangement.  However, for power, the distance between the front edge of the head and the pivot holes should be minimized.  This is accomplished by placing the pivot holes as close to the front edge of the swing arm as possible.  Mine are one inch on center from the front edge.  I believe they could be moved further forward without jeopardizing the integrity of the swing arm.  Using a harder wood with greater shear strength for the this piece would allow the holes to be safely moved even closer to the front edge.  In the same vein, the front edge of the head should protrude only minimally in front of the swing arm.  Mine extends one inch forward.  The greater the distance between the front edge of the head and the pivot holes, the less holding power the assembly has.

Pinned head joint.

The joint that connects the swing arm and the head is a pinned mortise and tenon.  The steel pin passes all the way through the tenon and locks it in place.  The orientation of this joint is unconventional, but has shown no signs of movement in three years of hard use.  The mortise is cut across the grain of the head.  This orientation allows the head to be short from front to back without danger of splitting in use.  The low profile head is easy to reach over and facilitates working on the other side of the head.

Literally a pain in the butt.

I won't say much about the seat of my shaving horse except that it slides in the groove created by the rails (which I like) and it causes physical discomfort after hours of continuous use (which I don't like).  I have been meaning to carve a new wider stool seat or sackback seat and I just never get around to it because I have this one which functions (barely).  My recommendation is not to carve a bicycle seat shape.  Make something wider that you will want to sit on all day.

With all of this clamping power optimization, both the work platform and the head of the shaving horse need some form of padding to prevent them from denting the wood being so firmly held.  I lined both with thick leather.

Expect more entries about this shaving horse design in the near future.  A good friend of mine is coming to build one with me next weekend, which will provide a great opportunity for me to offer more specific dimensions and construction details for this style of shaving horse.