Adjustable Rounder Plane or Witchet

 As far as I can see, these planes are no longer made and are rarely available second-hand, so making one might be a challenge. They are called adjustable rounding planes but they have different names depending on their use. Ladder makers call them "rung engines", rake makers call them  "stail engines" the term "stail" being the name of a rake handle. Boat builders call them "spar shavers" but in the USA they are also called "Witchets" but no one seems to know why they got this name. Anyone know ? Basically they allow poles to be rounded and made smooth e.g. rake handles or stails, or they can be used to produce tapers as the diameter cut can be varied.

This is a Varvill (York, England) large adjustable wooden rounder plane. Plane was probably made  between 1862 and 1904 but there is little information on the manufacture and when these type of wooden planes were made.

This shows the components of the above plane. Notice the brass liner and it's shape and the good quality wooden screw threads.

This is the plane partially open. It measures 9 1/2 inches long and 3 3/4 inches wide (i.e. the total width were the mouth sits) and 3 1/2 inches thick.  These measurements are approximate as I've not seen the plane.

This is a copy from "Ancient Carpenters' Tools" by Henry Mercer, 1929.

The plane illustrated by Mercer (shown above) is different from the Varvill plane in several respects:

1. It is larger, measuring about 12 inches long, 4.8 inches wide.  This allows more torque to be applied on using the plane.

2. The plane has two blades.

3. The shape of the mouth is less curved and more like a "v" shape.

4. There appears to be four dowels at each corner to guide the plane when the screws are applied. This is an option that I may need to consider after using the plane.

5. There is no brass insert in the mouth. I understand the insert aids turning and reduces the friction and also stops wear of the wooden mouth. 

This is shown in LeeValley tools and was made by T. Turner, Sheffield probably between  1840 and 1912.

The above "Turner" plane  is different again:

1. It has metal plates protecting the handles.

2. The blade is fixed with two bolts into the body of the plane.

3. The blade is situated at the edge of the plane rather than in the middle.

4. It is easy to measure the angle of the blade to the body from this photo(45 degrees).

I made mine from two blocks of beech each measuring 11 3/4 inches in length, 4 1/4 inches in width and 2 1/2 inches deep (after planing). These were planed true and the centre lines marked for the position of the blade. A "v" shaped hollow was cut on each base. This was made 3/4 inch deep and 2 inches wide. This was cut using a tenon saw, chiselled smooth and finally shaped with a round wood file,

The most difficult part of the construction was making the housing for the blade and wedge (there was no chip breaker). The blade was housed off-centre (3/4 inch from the one edge of the plane) as this would  help keep the dowel straight during the rotation through the plane. I had the iron and wedge from an old wooden smoothing plane that had several cracks in the base. This meant I had the old plane to guide me in making the new housing although the depth available in the new plane was less because of the "v" cut. Looking at the photos of old planes I decided that 45 degrees was normal so marked out the dimensions on the sides of one of the blocks. The mouth itself was marked 2 inches across and 1/2 inch wide centred on the centre line already marked on the block. The shoulders to trap the wedge were 3/8 inch thick, The housing was made with a chisel making sure the 45 degree angle was maintained through the body and meeting the line of the mouth.

The tightening screw holes were drilled in the centre of the width and 1 inch from each end. Unfortunately I made a mistake and drilled the wrong sized hole for one of the screw threads which meant that the handle of the screw was near the blade. My remedy was to shorten the screw iron and make sure the hand grip of the tightener was beyond the iron.

To try the plane I used some spare wooden screws I'd already made. but found that I needed to shape the blade so it that about  1 1/2 inches of the blade was angled (about 1 mm maximum)  leaving the final 1/2 inch at right angles to the side of the blade. Also the entrance to the plane was slightly widened to allow some lead-in space for the dowel. This worked OK but I found that the chips blocked the mouth easily. The blade housing was then modified by making it wider at the base and shaping the inside edges to ease the flow of the chip from the mouth. At the same time it was important to keep the strength of the wedge channel that keeps the blade in place..

I then made the screw threads on the pole lathe from some 2 inch diameter beech. 

Progress so far. The adjuster arms are temporary.

Adjusting screw

So finally the plane was oiled with linseed and was ready for use. I will report later on its use and how it works. I have tried it on some beech poles and found the best way to make it ready for use is to adjust the screws to get a comfortable fit in the mouth and then tap the blade into place to make contact with the side of the dowel at the widest part of the blade and start screwing. This will take a few passes to get a continues shaving from all around the dowel. Experience will tell but I can see that the initial adjustment is going to be crucial in its use.

 This cuts from 1 1/4 inches upwards but not sure of the limit.

Some modifications:

a) To reduce tear and wear on the base and also aid reduce friction, I fitted some brass plate around the outside of the mouth. For this I used 1.5 mm brass and screwed this in place as shown.

Brass plate fitted as described.

b) I also sharpened the blade so that it was curved at both ends to aid entry and exit from the blade when cutting. The centre of the blade was flat and so determined the diameter of the dowel that was cut.

When the screws were adjusted to give the smallest  diameter this gave a dowel diameter of 1 1/4 inches which is about the minimum size for a rake handle. It can make much greater diameters but the blade needs to be inserted deeper.

I have used it a little but not yet to make a stail. The crucial adjustment is the position of the blade as well as the shape of the blade. I have used it to reduce the diameter of a short pole by starting with the widest diameter to get a consistent cut and then gradually reducing the diameter and getting a continuous cut.  I haven't seen any account of the use of stail engines so I will update this blog when I have tried to make a stail.

Update on using the stail engine.

I have now used the plane to make a stail (handle) for a wooden rake using a length of hazel found locally in a stream. The plane worked well starting at the thicker end and working along the hazel gradually reducing the diameter as I progressed.  This produced a stail 3.54 cm (1 3/8 inches) at one end and tapering to 3.01 cm ( 1 3/16 inches) at the other and of total length of 173 cm (5 ft 8 inches). It took several passes to get the desired result with the first pass removing most of the bark. 

First pass from the thicker end of the stail

Second pass after removing most of the bark and cambian.

The finished stail. There is a slight bend so it was clamped whilst drying to straighten a little,

The stail  was set with the blade tilted slightly. The only problem was that the shavings tended to get caught in the throat of the plane but this was easy to check and keep clear as the plane was rotated. It didn't interfere in the operation of the plane as the shavings cleared away from the blade and I can't see an easy modification as the throat has to hold the blade in place.  Generally I am pleased with its operation.

The stail was bent slightly so it was clamped whilst drying.

Comments on the further use of the plane.

I have now used the plane to make several hazel and alder stails for wooden rakes. The video shows it in use making an alder stail. I generally start by removing the bark on the pole with a draw knife and on larger diameter poles, shaping it to try and reduce any unwanted curvature and smoothing any knots from side branches. I start the stail engine from the larger diameter end and do a first pass until the plane rotates without cutting. The key to using the plane is the adjustment of the blade so that it cuts into the wood at the leading edge but "runs out of cut" at the other end. Both ends of the blade are slightly curved to help prevent tear-out on the leading and trailing cuts. Also for larger diameters, the blade needs to go further down into the mouth to contact the wood and so cut. If the cut is too deep, I found that the thicker and wider shavings lead to congestion in the mouth and frequent stops to clean out the mouth with a wooden stick. Also with a deep cut there is more chance of tear-out making the pole less smooth. I found the best position of the blade produced a wafer cut, probably about 3/4 the width if the mouth. It was easy to remove 3 mm on the pole diameter on each cut and also keep the mouth from clogging with shavings. It is also important to keep the plane a tight fit to the pole by adjusting the arms. If the plane "wobbles", the pole will be marked erratically by the blade. All in all, the rotary plane offers many advantages, e.g gradually changing the pole diameter or tapering. However, it does take quite a lot of practice to get it working well and I guess each plane will be different. I am pleased I made a large sized plane with good grip on the adjusters for rotating the plane.