AMERICAN (HOUSTON) SINGLE END TENONERS

These are my tenoners. There is not much I make that doesn’t require the work of these fine machines.

This is the second one which I recently relocated. Adding another line. The original wrenches in the foreground. When I re-powered this machine, it was with more power. The belt dressing in the picture was my response to what I perceived as belt slip. Turned out it was pulley slip. The tailshaft has one wood pulley on it, and the clamp had dried a bit. Wood pulleys are split in halves with a 3 ” hole in the center. Maple split bushings are made to reduce the diameter to the shaft size. When the two sides are bolted together, it all squeezes tight. But after a dry period of no use, they can loosen up.

Now this is the first one. The daily user for twenty years now. The tailshaft is original on this one. Still have the tight/loose pulley laying around somewhere nearby. The belt guard is removed so you can see how the main belt is “threaded” through the spindles and tensioner. The tenoning heads turn in opposite directions at about 2750 rpm. There are two heads on each spindle. The out side heads differ in that they are end milled with dovetailed slots into which are clamped spur cutters. The spur cutters prevent tear out of the grain beyond the shoulder of the tenon; scoring.

This design probably dates from the 1870s. Other companies had similar designs but with a sliding table rather than this compound rolling table. It has a very nice action. This machine was made 1897 or a little later.

The upper head adjusts relative to the lower, up and down for tenon thickness, and laterally for shoulder alignment. Then, the other rod is used to move the whole head frame up and down relative to the table locating the tenon. There is a lock for this movement. Don’t forget it.

The coping heads are attached to the upper and lower head frames so that the cope is always right where you put it relative to the tenon. The saw is fixed in elevation relative to the table but adjusts laterally from 0″ to 7″ which is the range of tenon length this machine is capable of.

Here’s a shot of the saw, the lower cope spindle with a modern round head and the tenoning heads. That little notch in the tenoning knives fits into a notch in the rim of the head. I believe this fit is rather important. The arc of the grind is something to never lose once you get it right. I have metal templates. I slip stone these a lot to keep them as sharp as possible.

That hold down handle I had made from some very strong but limber foreign wood. An instrument builder made them for me after seeing what was required. You don’t want to take a chance on any thing that might break.

The upper cope is set aside for sash work. For sash we only need the lower cope. The round heads were made for me by my old machinist. I thread them on. When I sold my prior nuisance tenoner, I kept it’s tooling, which was threaded. The other tenoner has straight spindles for the old style coping heads. Old style cope heads use hooked knives for a 45 degree cutting angle. Good for crossing the grain. The round heads I have made at a 27 1/2 degree cutting angle to match my sticking heads. That way when I grind knives, the mating patterns are the same.

I have learned over the years that it is easier to get cope and stick right by hand than getting cutters and knives from the saw shop to fit good. The knife on the left is carbon steel, on the right HSS. Both are ground by hand, unlike carbide.

This shows the unique shape of tenoner knives. The curve is a segment of an ellipse determined by the cutting circle and the angle of skew. There are no knives on the inside head. Notice the triangles. When running the knives close, you need to knock those corners off. I prefer to run close. These knives give plenty of tenon for glued doors. Now through morticed and wedged (Victorian era and earlier) doors would require the inside knives, or, two passes.

These are HSS inlay knives. Inlay are great knives. The spurs are HSS, kind of like skinny shaper steel but not. I prefer a softer steel for spurs so I can swage them. They clamp in.

This is what the upper spindle looks like. The v-grooves are to keep the from drifting around. That end sits in a bearing housing that adjusts laterally, backing and forth-ing the spindle through the right bearing. The saw adjusts this way too. Moulder spindles also adjust like this. Pretty slick unless the range is not used from time to time or someone runs the bearing dry and tears things up. So this how we get to offset or not the tenon shoulders.

This the cut off saw arbor. The belt comes out from the left and right angles over the pulley to make it go. It cuts clockwise. The pin spanner (?) takes off the saw. In the distance is the lever that moves the spindle back and forth through the pulley which has a key slot through it for a key in the spindle to pass. There’s a nice graduated scale on the back kinda hard to see here.

But easy to see here! The bearing cap is off here showing v-grooving. There is a thumb screw behind the handle there that locks things down. I also pinch tight the bolt there when things are the way I want.

These tables are great. Well, I like them a lot.

This shows the tenoner at work. The spring stop in the stop rail can be seen up against the face down shoulder. This is a 10/4 door rail. The key to finish part length is the shoulder to shoulder length. The spring stop gauges that to the spurs on the cutter heads. Shoulder to shoulder is the panel or glass opening dimension in the finished item.

Here’s another technique. Use two stops. One high, one spring, for first and second passes. Then, when going to a different size rails, slide the mid table. It will take the stop rail with it an preserve the tenon settings in the stops. If the tenon is real short, turn the spring stop around. I like this technique for heavy parts like door rails. Otherwise, I use the spring only and move it when changing sizes.

COPING HEADS

Old coping heads are square and use hooked knives like these. The two pictured are for ogee sash. These were made of carbon steel, bent and treated at the forge by someone who knew what they were doing. The cutting angle on these is about 45 degrees. They vary slightly in angle as the forge work is a little variable.

This is a view from behind the saw. It shows the relation of the cope spindles to the tenoning heads, the clearance for longer tenons, a sash part.

These were a common cope head for a long time. This is a Yates-American. Each head is numbered and the bolts are numbered to match the head. They make a silky chip that will pack but has little density.

Generally, I use the round cope heads shown up thread. With smooth steel in order to get them tweaked around just right. Not sure the speed on the copes, but it’s faster than the tenoning heads.

At work. The v-rails are somewhat self cleaning but it’s good to keep an eye on them. The tools go in the box built in the frame. The shavings are a distinctive skew knife chip. If one has a chip blower, the ducts go in and in front of the frame, or the guard is removed an a hood is placed over the top head.

I always advance the work at a steady pace. Some men race through the cope and saw. I keep a hand on the grip in spite of it being locked at the pawl just in case. Sometimes I unload the part behind the saw, sometimes I draw the table back through and then unclamp and withdraw the part. I am not consistent and I am not sure why.

ADDITIONAL DETAILS

Here are some details requested on another forum which is frequently down so I’ll put them here instead.

The stops are in pairs. A spring loaded and a high fixed. I show them in use up-thread.

This is an original tool kit. The spanner for the saw, the J for the tenon spindles’ locks, the other for the cope heads.

Dove tail fits in the rail. One can just see the spring in the retractable stop.

All the parts on this tenoner table are “4”.

This is under the table. One can see by how clean it is that I fumble around under here a lot. this is where all the action is changing widths and going from bars to muntins.

The center screw locks the stop rail in place to the middle table. The two bars and near and distant screws are clamps that secure the middle table to the table in its slides.

MACHINE IN MOTION

This is the other one.  The one without guards yet.

 

 

 

 

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