Operation Clay Pipe

Making a clay tobacco pipe

Text not yet fully proofread...

     While reading a discussion on clay tobacco pipes, I decided, for no very good reason, to try my hand at making one myself. Ceramics, having been an occasional hobby for the last 20 years means that I has some of the basic knowledge and tools to make an attempt -or at least get myself into trouble. This post chronicles my effort.

     Historically clay pipes have been cast in a mold; this seemed like the best approach, with the advantage that once the mold is constructed multiple copies of the pipe can be easily made. Two videos available on the internet (here, and here), and many photos of historic pipes, were helpful starting points.

Be careful of clay pipes, don't do this to your teeth!  

Photo from the Smithsonian Institution, link here.

     Pictured below are my first attempts at getting a usable "master pipe" to construct the mold. It quickly became clear that I was not going to be able to produce a smooth and round stem without having it mangled while refining the bowl. The stems were therefore extruded, in what amounts to a large caulk gun with replaceable dies.

First batch of prototypes, extruded stems on the left.

Selected prototypes and protopipes with extruded stems attached to the bowls. Note the spurs have not yet been added.

The final four prototypes with spurs attached. The pipe on the bottom will be used to make the master mold.

Not having enough soft modeling clay to make the mold base, I used a block of foam insulation, roughly doug to fit the pipe. I wanted the stem to be parallel to the mold to aid, if necessary, inserting at metal wire to form the airway. The notch in the insulation, seen in the upper right, is to allow access to the bowl, either to pour in liquid clay, or to for the chamber opening if filled with malleable clay.

Oil based modeling clay is then packed around the pipe to form a smooth and tight juncture where the mold halves will meet. In retrospect, making the proto-pipe out of the oil based clay, and the mold base out of regular clay, would have been easer as the oil based clay did not adhere well to the foam insulation making it hard to keep in place while smoothing.

The sides of the mold are formed with cardboard, sealed with clay, and finally all surfaces coated with diluted Murphy Oil soap to act as an a release agent.

The first half of the mold has just been poured with No. 1 Pottery plaster.

After the plaster sets the base can be removed.

The surface of the mold should have been nice and smooth, clearly mine was not, so the next step was to smooth it out and add mold keys to keep the two halves of the mold aligned. Also, apparent in other photos, the mold seam, which should have bisected the pipe is not really in the middle, I was rushing....

The mold cleaned up with mold "keys" carved into the plaster.

Same procedure as pouring the the first half.

Opening the mold for the first time!

I cleaned up the mold top with a scraper, more for cosmetic than practical purposes.

     Traditionally moist clay is roughly formed, placed in the mold, and the two mold halves forced together. The bowl is then hollowed and the airway formed with a metal wire. I thought I would try slip casting instead. Slip, is basically liquid clay that can be poured into a plaster mold, the mold absorbs the moisture leaving behind a film of leather hard clay, the thickness of which is proportional to the time left in the mold. If not left in the mold too long, which I did once or twice (forming a sold pipe), the airway and chamber of the pipe will be left open. This is not the historically accurate process, but I have heard that the technique has been used in some reproduction pipes.

The box of liquid clay, or slip.

As a first test of the slip, I poured some into a clay tile mold I had previously made.

Here is the Labrador Retriever tile cast with slip.

The mold after the slip was poured, left to adhere for about 6 minutes, and excess drained. A drinking straw was used to blow any remaining liquid slip out of the pipe stem (sounded like snot).

The excess on the mold platform is cut away with a metal spatula.

Opening the mold after the first casting. Note the slip did not make it to all parts of the mold leaving a large section of the stem without clay (upper right half of pipe stem).

The same pipe pictured above. When removed from the mold the clay is still soft enough that the stem can be bent if desired.

Stem airway.

Pipe cross section, note that the pipe is shaped like a funnel. The internals of the pipe would resemble a briar pipe if the clay had been pressed into the mold with the chamber and airway being formed mechanically.

The first "pour" with a complete stem.

The pipe needs to be smoothed after removal from the mold, here the mold lines are obvious. Note that the mold seam is not centered on the pipe (my mistake), this also made the pipe more difficult to remove because a slight overhang is created in the mold

The "first" pipe with no air bubbles, not yet fired, with dog hair (Australian Shepherd) stuck in the middle part of the stem.

     Time for firing. Although this clay is rated at cone 5/6, clay pipes are traditionally "under-fired" so that they remain absorbent. I started at cone 06.

Pipes in the kiln for the first firing. The other things are mugs getting glazed.

Looking in the "peep" hole of the kiln, very hot... note my reflection on the kilns metal jacket.

     The first batch of pipes were fired at cone 06, I smoked one, and got a earthy wet chimney smell/taste at points. Guess that this may have been too low a temperature, the first pipes, plus some new ones were fired at cone 04 (hotter than 06).

     The kiln did not shut itself off when it was supposed to (the kiln sitter had an issue), below is an 04 witness cone that is obviously over bent. I'm guessing by a cone or two, so this firing may have been around 03 or 02.

Overheated 04 cone ... 

Batch of finished clay tobacco pipes. First from the right has wax on the tip, second from the right has clear glaze.

Cracked clear glaze on the stem. I think the glaze needed a lower temp....

Pipe rim; note, that I didn't get it perfectly round....

Orlik Golden Sliced packed in the pipe.

I smoked one of the pipes fired at the higher temperature and didn't get as much of the "earthy" smell/taste, so I think the higher temperature firing may be the trick.

My work area, and my two helper dogs!