Showing posts with label Planes. Show all posts
Showing posts with label Planes. Show all posts

Sunday, July 12, 2015

Seatbelts for the planes - Situation normal.

  My current project was to make new shop furniture to hold my sharpening station, and some lumber and the like.  Seemed straight-forward enough.
  I started to get to thinking that adjusting the mortise gauge to match the mortise chisel I was using was just getting to be too much of a burden, and it occurred to me that if I made a whole mob of mortise gauges purpose-set for my mortise chisels then I wouldn't have that problem again!  Huzzah!   
  So I started cutting up oak and maple scraps to make the gauges.
  That's when I started to really feel the 'rust' in my skill-set, so I decided I would really focus on doing the pieces up properly 'four-square'.  No problem.
  That's when I realized that I do not, in point of fact, have a panel gauge which is a requirement for doing things Properly Four Square when they're more than about 4" wide.
  Now the current project is a panel gauge.
  I have cut the pieces, and cleaned them up 'four-square'.  I finished that yesterday.  Today is the day planned to start shaping the stock of the panel gauge.
  This brings me to my plane till.
  I made this plane till about 5 years ago, and my planes have sat on it without complaint for all that time, and never has even one plane even hinted at a desire to leap off of the till.
  'Til yesterday.
  I used to have my bench against the wall.  It wasn't possible for me to bump against the planes on the till because the bench was in the way.   Now the bench is in the middle of the room and I pass close by the till all the time.
  I knocked my Veritas bevel-up smoother off of the till yesterday, at which point it plummeted down to the (and it makes my marrow quake to admit this) ceramic tile floor below.  It was neither a proud nor a pleasing moment.  I spoke sternly to myself and told me to give the till a wider berth so that it wouldn't happen again.  Apparently I am no better at listening than my wife claims, because I did it again this morning.  To the very same plane.

  My current project changed again, and it became 'harnesses' to keep the planes from plummeting in case I bump them again.
  I have always avoided this method of securing planes in the past, because it requires extra thought and generally an extra limb to extricate the plane from the till.  Today, however, it was a necessity to protect the planes regardless of the damage to my delicate sensibilities.
  A half hour spent spelunking for my old camping gear produced some para-cord, which doesn't look right, but which works fine.
  The job is done, the planes are safe, and I can get back to working on the panel gauge.  I'll come up with a proper way to restrain the planes when I have more time to think.

M.Mike

 
  

Saturday, July 11, 2015

Something to remember when planing flexible stock

When planing flexible stock (like a 1x1) the face you're planing will be greatly affected by the face of the material that's on the bench.  If the bottom face has a hollow in it, you're going to have a bulge in the side you're planing.  After planing off the same bulge four times in a row I finally clued in.  Either shim up the bottom so that you can't cause it to flex when you press on it, or, if it's short enough, pinch it in the vise so that it's supported all the way along.
A big board isn't flexible enough to have a problem with this, but it was certainly a problem for me this morning, and it had me baffled for a good half an hour.

M.Mike

Sunday, July 6, 2008

To crown or not to crown

Gentle readers, I have had an epiphany. It has to do with crowning plane blades, and names for planes.
I read an article by Adam Cherubini about the subject, and it resonated with me to such an extent that my ears are still ringing.
An archaeologist and historian named Henry Chapman Mercer wrote a book in 1929 called "Ancient Carpenter's Tools" wherein he decided to classify tools in order to give them 'true names', similar to the way biological nomenclature works. I liken it to genus and species. Using this analogy, the three genus of planes were set as levelling when the plane is used on a surface to make it flat and/or smooth, fitting when the plane is used on a surface no wider than its blade to create a new surface that will match another surface, and lastly ornamentation, which is where a plane is used strictly for a decorative effect.
Within each genus there are many possible species, but all share common traits. Yes, there are exceptions. There are always exceptions. However, here are some common traits:
Levelling planes like fore planes, smoothers, and try planes, have crowned irons and tight mouths. Exception - the fore plane has wider mouth as the surface finish isn't as important as speed.
Fitting planes like rabbet planes, match planes, plow planes, router planes, etc. have irons ground straight across and are used to produce the surfaces of joints. They have wide mouths because the surface won't be seen in the final product, so the surface finish isn't important. The exception is the jointer plane, which should have an iron ground straight across like other fitting planes, but it has a tight mouth because leaving a rough surface can be visible from the side when the joint is glued.
"But Mike!," I hear you exclaim, "the experts pretty much all use crowned irons in their jointer planes!"
Here's the interesting bit. Are you ready for this? Those aren't jointer planes. Those are try planes. Try planes are levelling planes, with a crowned iron. A jointer plane is used only for jointing edges for glue-up. Making a joint. That's it. It's a fitting plane.
Long has the nomenclature been rather... lax. Jack planes and fore planes are, in some books, the same, and in other books different. The same goes with try planes and jointers. I think Mercer was on to something.
I have a 'jack plane' which I use only for fitting, with a straight iron, so it is actually a short jointer.
I have a 'jointer plane' which I use for levelling, with a crowned iron, so it is actually a try plane.
I have a 'block plane' which I use for levelling, with a crowned iron, so it is actually a smoother.

It may seem complicated, but for me it has made things a whole lot clearer, and also clears up the reasons for some of the previous confusion. A wooden plane 24" long could be either a jointer or try plane depending on what you were going to use it for. Put a flat grind on it and it's a jointer. Put a camber on it and it's a try plane. If the plane didn't have an iron in it, then what kind of plane would it be?

The common jack plane, I suspect, was called such because you would have multiple blades for it and convert it from a short jointer to a fore plane to a short try plane on a whim.