Canes

Signed-In Members Don't See This Ad

monophoto

Member
Joined
Mar 13, 2010
Messages
1,451
Location
Saratoga Springs, NY
Recently, I tried making a walking cane – mainly to prove that I could do it. Here are a few thoughts based on that initial experience:
1. Length: Ideally, canes are sized to match the user. The ideal length, including the handle, is the distance between the floor and the user’s wrist joint while standing. Obviously, this doesn’t need to be rocket science, but if there is to be an error, it is better to err on the side of slightly too long.


2. Diameter: my research didn’t disclose any suggestions on diameter. Canes aren’t intended to support the user’s weight; instead, the purpose of a cane is to assist in maintaining balance when the user is weak on one side. But one has to be concerned about the consequences of unexpected failure of a cane that causes the user to fall. I found one YouTube video in which the maker chose to drill out the shaft and glue in a length of steel all-thread rod. That would definitely be strong, but it would also add a lot of weight. However, it seems to me that the goal is to be strong enough without being too heavy, with diameter and the characteristics of the timber selected for the project being the key design factors. I made mine from ash, and turned the shaft to a 1 1/8” diameter. In retrospect, I suspect it could have been a bit thinner – perhaps 1”.


3. Constructability: This was the most difficult technical challenge. Turning the shaft as a single spindle sounds like a great idea, but that requires a lathe with a long bed as well as a steady-rest. I don’t have a steady, and my midi-lathe bed is only 18”. It didn’t make sense to purchase a bed extensions for one project and I don’t really have enough room in my shop for a longer bed. So I opted to turn the shaft in three sections that were glued together using mortise and tenon joints. There are several elements that contribute to the strength of this construction:

  • Making the joints long enough to get a good long-grain to long-grain bond. I would be hesitant to use tenons shorter than 1”
  • Making sure that each tenon bottoms out in its mortise. A gap at the bottom of a mortise will be a weak point in the shaft
  • Making the walls of the mortises about as thick as the diameter of the tenon. Practically, the mortises have to be drilled using whatever bits are available, and the tenons then fine-tuned to fit.
  • Using a good quality PVA glue to assemble the joints.
To disguise the joints, I added a thin ring of a contrasting wood turned to form a bead at each joint.


4. Handle: there are two options to choose from – a knob (essentially, a turning that looks much like a bottle stopper, only larger), or a handle. I chose to use a handle turned in three steps on two axes. I started with a blank with a rectangular cross section and with a hole drilled in one side to receive the shaft tenon. The first turning between centers was to put a spigott on one end for remounting later. Next, I remounted the blank on the parallel axis (again between centers) to shape the top of the handle. Third, I remounted it again, gripping the spigot in a chuck and with the tailstock for support to shape the bottom of the handle (leaving the area where the shaft would attach flat). In this stage, I was able to turn away the evidence of the second turning and its axis, before reshaping the spigott into a ‘nose’ and parting off. Final sanding smoothed everything and removed the tailstock dimple from the second axis turning.


5. Attaching the handle: I opted to use a dowel pin that that runs from side to side through the handle and the shaft tenon. I used contrasting wood so that the dowel became a decorative element. Another option is to use a dowel (perhaps fiberglass) that runs longitudinally in a blind hole inside the handle on Axis 1 (ie, it enters from the back of the handle, but stops before it reaches the front). There is an opportunity to drill the mortise hole for that rod as part of the second turning. The hole can later be disguised with a single plug that is sanded smooth. This approach is a bit more work, but it may create a stronger handle, and it has the advantage of also eliminating a tailstock dimple left from turning on Axis. Both of these options probably fall into the ‘belt and suspenders’ category, and simply gluing a shaft tenon into a mortise in the handle might be adequate.


6. Foot: you can purchase metal ends for canes, but the simpler choice is a rubber foot from the hardware store. They are available in either white or black, and in a selection of diameters. It’s prudent to check the sizing before finish turning the shaft. Ideally, the foot will fit snugly, but it is always possible to add some polyurethane glue to hold it in place.


7. Finish: canes get rough use, so the finish needs to be fairly tough and/or amenable to repairs. I was torn between wipe-on Polyurethane and a commercial Modified Tung-oil finish; I chose the Tung-oil finish because it would be less ‘plasticky’ and has a reputation for being easily refinished if necessary.


Rather than turning a handle, it is possible to purchase handles. Timberlines.com is a specialty supplier of cane components and offer handles, shaft couplers (to make collapsible canes for travel), and metal feet. Lee Valley also carry some cane components.

Bottom line: it was a fun project that didn’t require any tooling that the ordinary woodturning shop isn’t likely to have, and it has a practical use. My total out-of-pocket cost for the project was less than $5 for the rubber foot (actually for a package of four – I now have three spares for future projects). I don’t need a cane today, but you never know what the future might bring!
 

Attachments

Signed-In Members Don't See This Ad

Tom T

Member
Joined
May 12, 2012
Messages
1,883
Location
Sanford Florida
Thank you for a detailed look at this project. I have thought about turning one several times. The older I get the closer to needing one I am.
 

dogcatcher

Member
Joined
Jul 4, 2007
Messages
1,808
Location
TX, NM or on the road
I am disabled and have had to use a cane for over 20 years, this is my experience. A cane with a metal tip is an accident waiting to happen. On a smooth floor it can and will eventually slip and the person will most likely be on the floor with the cane.

The handles, there are decorative and there are functional cane handles, the fancy carved ones are fine for looks, but they have to be comfortable for long periods of time. I have to use my cane both for balance and support, I have several canes that sit in the cane bucket because for me they are unsafe.
 

randyrls

Member
Joined
Feb 2, 2006
Messages
4,147
Location
Harrisburg, PA 17112
maker chose to drill out the shaft and glue in a length of steel all-thread rod. That would definitely be strong, but it would also add a lot of weight. However, it seems to me that the goal is to be strong enough without being too heavy, with diameter and the characteristics of the timber selected for the project being the key design factors.

Louie; I wonder if a carbon fiber tube would add strength without being too heavy. I did a quick check and found them in 39" lengths for around $20.

And, yes all of use are getting closer to that age.....
 

monophoto

Member
Joined
Mar 13, 2010
Messages
1,451
Location
Saratoga Springs, NY
After looking at the cane for almost a year, I decided to do another while making some design improvements. Some of the concerns I wanted to overcome included:
1. The overall feeling was that the cane was bulky - the handle seemed heavy, and the (essentially) uniform 1 1/8" diameter of the shaft created a sense of weight (even though it actually wasn't very heavy).
2. I had chosen to celebrate the joints between shaft sections with small bits of contrasting timber that formed beads. While the basic idea assured that the joints weren't obvious, I later decided that the beads were too much..
3. The original design involved 'loose tenons' - essentially short dowels that were glued into both sides of the shaft joints. In retrospect, I decided that the construction would be stronger if the tenons were integral parts of the shaft sections.
4. While the side-to-side pin securing the handle to the shaft was certainly strong, I wanted to try something different.

The improvements that I made included:
- rather than leaving the sides of the handle flat, I rounded them over more so that the cross section of the handle is more of an oval. The result is that the handle doesn't look as heavy. I also made the handle from a contrasting timber - canary wood.
- also, the shaft was given a distinct taper - 1 1/8" at the top, tapering to 7/8" at the bottom. I don't think this affects the strength, but it keeps the cane from looking so bulky.
- after carefully measuring the available working space on my lathe, I opted to make the tenons simply extensions of the shaft rather than 'loose tenons' that are glued into both sides of each join. I found that I could rough turn each section of the shaft between centers with a 2" long 3/4" tenon on one end, and then grip the tenon in my scroll chuck to drill a 5/8" hole in the other end to receive the tenon from the adjacent section. Then, after glueing a thin ring of contrasting wood onto the tenon to 'celebrate' the joins, I could finish turn the section, reducing the tenon to 5/8" and introducing the taper. I carefully measured the diameter of the ends to assure that the joins would match. And after the sections were glued together, I sanded the joins to eliminate any mismatch.
- the handle was attached by means of a 7/8" tenon n the top section of the shaft that was glued into a matching hole in the handle. After the glue cured, I drilled a 1/4" longitudinally through the handle and shaft tenon (from the front and extending toward the back about 1" past the shaft tenon), and then inserted a length of 1/4" fiberglass rod. The fiberglass rod was glued in using epoxy. Finally, the end of the hole was plugged with a short dowel turned from a scrap of canary wood to match the handle, and the end sanded smooth.

The resulting cane is equally functional, but looks much nicer.

Bottom line - there is always room for improvement.

(Incidentally - I also modified the original cane. I used a flush-trim saw to remove the contrasting beads, and then smoothed over the joins using a rasp. Sanded everything smooth and refinished. I looks nicer now.)
 
Last edited:

monophoto

Member
Joined
Mar 13, 2010
Messages
1,451
Location
Saratoga Springs, NY
Followup -
A feature that some cane users want is the ability to break down a cane into two parts, perhaps for packing in a suitcase. Lee Valley and Treeline both sell brass couplers that are intended for this purpose. I wanted to see if I could make a collapsible cane using more readily available components. It is usually possible to purchase a 'threaded wood insert' at hardware and big box stores. This is a brass fitting that screws into a hole in wood to create a reusable brass female thread. Combining that with a length of threaded rod should do the trick. Threaded inserts are available in a variety of sizes - I chose an insert designed for use with 3/8"x16tpi rod.

The challenge with threaded inserts is that they are intended for use in face grain, and when inserted into an end-grain turning, especially one where the OD of the turning is not that much larger than the OD of the insert, it is possible for the insert to split the turning. I found that there are two things that can be done to minimize the risk of that problem. The first is to make sure that the hole that is drilled in the end grain to receive the insert is the proper diameter. In some hardware stores, inserts are sold from boxes that are labeled with the required hole size, but in big box stores, they are often supplied in plastic bags that don't indicate the appropriate drill size. Rocker publishes a table of recommended pilot hole sizes for threaded inserts.

The other issue is that the insert needs to go into the hole exactly on-axis - it it tilts a bit, that can split an end-grain turning. I recently saw a video that demonstrated a trick to assure that the insert is properly aligned. The key is to first drill a hole with a diameter that matches the threaded rod that will be screwed into the insert - that hole needs to have a depth that is twice the length of the insert. Then, the open end of that hole must be reamed out to the diameter required by the insert. Then, when installing the insert, screw the rod into the insert with a length slightly greater than the length of the insert protruding from the end of the insert as shown in the sketch. Then, when the insert is installed, the end of the rod will align the leading end of the insert to the axis of the turning, while the insert hole will align the trailing end of the insert, assuring that it remains exactly on-axis.

One additional suggestion about threaded inserts - once installed, there is no way to get them back out without destroying the workpiece. The threads are coarse, and the recommended pilot hole may leave a bit of gap. So to assure that everything is secure, I put a drop of a gap-filling glue (either thick CA, epoxy, or polyurethane) on the threads before screwing the insert into the hole.

ScreenHunter 56.jpg
 
Top Bottom