Tag Archives: Duncan Hill Patent information

Restoring a Second Duncan Hill Aerosphere Rusticated Apple – another of the 12 Pipes

by Steve Laug

Back in January I received an email from Robert with a group 12 pipes that needed to be restored in various ways from cleanup to restemming. I chose to work on the second Duncan Hill Aerosphere pipe that he sent next. It is a nice-looking rusticated apple – one of my favourite shapes. The bowl and shank were in good condition but the finish was very dirty. The bowl had been reamed at some time so there was no cake in it. The rim top was clean but had some darkening around the top and the inner edge. The pipe was stamped on the underside of the bowl and shank and read Aerosphere [over] Duncan Hill. This one came with the original stem in place on the shank. It had the triple rings on the stem and a white acrylic (Delrin) tenon. It was oxidized and calcified on the button end. There were light tooth marks on the top and underside of the stem near the button. It had the classic Aerosphere system stem with the carburetor on the left side of the half saddle stem. I took some photos of the pipe to show its condition before I started my work on it. I took some closer photos of the bowl and rim top to show its condition before I started my work on the pipe. You can see the clean bowl and the darkening on the rim top. The stem photos also show the general condition of the stem as noted above. I took a photo of the stamping on the underside of the bowl and shank. It was stamped on a smooth panel and was faint but readable. It reads as noted above. I removed the stem and took a photo of the parts of the pipe to show the look of the pipe.Before I started work this one I reread what I had posted on the Duncan Hill Restem job I did. I have included what I found below. I Googled Duncan Hill Aerosphere and the first bit I found was from a Google group for ASP. There I found the following quote. I have the reference link placed at the end of the quote if you want to follow up on the information:

“The Duncan Hill Aerosphere smoking system (U.S. patent #4,275,747) utilizes the same principle of physics as the manometer. The Aerosphere, visible as the brass pin on the side of the mouthpiece, brings a scientifically measured amount of air into the stem with each puff. The control of the amount of air and the velocity of the air produces two effects that result in superior smoking pipe performance.” https://groups.google.com/forum/#!topic/alt.smokers.pipes/GUxdN5Dus4Q

I decided to start on the bowl itself. I worked over the rim darkening with a folded piece of 220 grit sandpaper. The smooth rim top was crowned so it was an easy process to clean it up at the same time as the edge.I scrubbed the exterior of the with undiluted Murphy’s Oil Soap and a tooth brush. I worked on the rustication and the smooth rim top. I rinsed it off with warm running water and dried it off with a cotton towel. It is definitely looking better. I worked on the rim top and edges with 320-3500 grit sanding pads to further remove the darkening on the briar. It is improving with each pad. I wiped the top down with a damp cloth to remove the sanding debris. I polished it with 1500-12000 grit sanding pads and wiped it down with a damp cloth after each pad. The rim top looked very good. I cleaned out the shank, mortise and the airway in both the shank and the stem with alcohol, cotton swabs and pipe cleaners. The shank was very dirty. The airflow is great.I rubbed the bowl down with Before & After Restoration Balm. It is a paste/balm that works to deep clean the finish, enliven and protect the briar. I worked it into the briar with my finger tips to make sure that it covered every square inch of the pipe. I set it aside for 10 minutes to let it do its work. I buffed it with a cotton cloth. The briar really began to have a deep shine. The photos I took of the bowl at this point mark the progress in the restoration. I set the bowl aside and turned my attention to the stem. I scrubbed the stem surface with Soft Scrub to remove the oxidation and the calcification. It looked much better. The tenon was a clear/white Delrin that was stained with tars and oils.I sanded the stem with 320-3500 grit sanding pads. I wiped the stem down after each pad with an Obsidian Oil impregnated cloth to remove the sanding debris. It began to take on a shine.I polished the stem with micromesh sanding pads – dry sanding with 1500-12000 grit pads. I wiped it down with some Obsidian Oil after each sanding pad. I polished it further with Before & After Stem polish – both Fine and Extra Fine and then wiped it down another time with the oil. I put the Duncan Hill Aerosphere Rusticated Apple and the stem back together. I polished the bowl and stem with Blue Diamond to polish the briar and the vulcanite. I gave the bowl multiple coats of Conservator’s Wax and the stem multiple coats of carnauba wax. I buffed the pipe with a clean buffing pad to raise the shine. I hand buffed it with a microfiber cloth to deepen the shine. The pipe polished up pretty nicely. The original brown stains gave depth to the rustication and worked amazingly well with the polished vulcanite half saddle stem. The grain around the bowl and shank and looks quite remarkable. This is truly a beautiful Duncan Hill Aerosphere. The finished pipe is shown in the photos below. The dimensions of the pipe are Length: 6 inches, Height: 1 ½ inches, Outside diameter of the bowl: 1 ½ inches, Chamber diameter: 7/8 of an inch. The weight of the pipe is 1.52 ounces/42 grams. This is such a unique shape that I am going to enjoy it for awhile before deciding what to do with it. Thanks for walking through the restoration with me. Cheers.

As always, I encourage your questions and comments as you read the blog. Thanks to each of you who are reading this blog. Remember we are not pipe owners; we are pipe men and women who hold our pipes in trust until they pass on into the trust of those who follow us.

Restemming and Restoring a Duncan Hill Aerosphere Smooth Pot – another of the 12 Pipes

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by Steve Laug

Back in January I received an email from Robert with a group 12 pipes that needed to be restored in various ways from cleanup to restemming. I chose to work on the Duncan Hill Aerosphere bowl next. It is a nice-looking smooth bowled Pot. The bowl and shank were in good condition. The bowl had been reamed at some time so there was no cake in it. The rim top was clean but had some darkening around the top and the inner edge. The finish on the bowl was dirty with some visible fills on the left side of the bowl. The pipe was stamped on the left side of the shank and read Duncan Hill [over] Aerosphere. There was a tenon in the shank and three rings on mortise end of the tenon. There was an orange acrylic ring sandwiched between two brass rings. The bowl came without a stem and I would need to either find an Aerosphere stem or fit the tenon on an existing stem. I took some photos of the pipe to show its condition before I started my work on it. The tenon was removable and I turned it out of the bowl. The sandwiched triple ring fitting on the tenon was also removable.Before I started work on fitting a new stem to the shank I did a bit of work on the brand itself. I Googled Duncan Hill Aerosphere and the first bit I found was from a Google group for ASP. There I found the following quote. I have the reference link placed at the end of the quote if you want to follow up on the information:

I also found a link to an advertisement for the brand featuring the designer in Popular Mechanics Magazine, February 1980, pg. 31 on Google books. Here is the link:
https://books.google.ca/books?id=m9UDAAAAMBAJ&pg=PA31&lpg=PA31&dq=Duncan+Hill+Aerosphere+Pipes&source=bl&ots=tR4egGI0ig&sig=XeACE0-Vh19-1JNcA0kAgS87kRI&hl=en&sa=X&ei=p1QbVbPTEpLvoATEpoLoCQ&ved=0CBwQ6AEwADgU#v=onepage&q=Duncan%20Hill%20Aerosphere%20Pipes&f=false Next is an advertisement from Popular Mechanics Magazine, September 1982, pg. 216 on google books. Here is the link. https://books.google.ca/books?id=f9kDAAAAMBAJ&pg=PA216&lpg=PA216&dq=Duncan+Hill+Aerosphere+Pipes&source=bl&ots=fsZtVqD0z9&sig=Kl3wI-76NJqpFxAg8SPndnnWyqM&hl=en&sa=X&ei=owEcVdGGKdj9oQSD_4L4Bw&ved=0CCgQ6AEwAjgo#v=onepage&q=Duncan%20Hill%20Aerosphere%20Pipes&f=false Finally using the patent number in the ASP quote I was able to find the patent documents for the pipe on the US Patent Office site. I have included the documents from the US Patent Office here. There are four pages – 2 of drawings and two of description. I love finding this old information and reading about the persistent search for the dryer cooler smoking pipe that has led to many creative solutions. It lends some colour to the work of my refurbishing to be able to read about the design ideas and the inventors themselves as I work on the pipes. Armed with new information it was time to work out a new stem for the pipe. I went through my collection of stems and did not have an Aerosphere stem to replace it with. I did find a nice looking acrylic black stem that would work very well. It did not have a tenon and would need to be drilled out to receive the Duncan Hill tenon I had. The beauty was that the diameter of the shank was very close to the diameter of the stem.I drilled out the airway in the stem with increasingly larger drill bits until I had it open enough to fit the tenon. Once I had it drilled out I checked the fit of the tenon in the shank and in the newly drilled out stem. The fit was perfect in the stem. I painted the tenon end that fit in the stem with black rubberized CA glue. I pressed it in place in the stem and set it aside until the glue cured and the new tenon was solid.With the tenon cured I put the stem on the shank and took a photo of the new stem. Though it did not have the Duncan Hill carburettor on the left side of the stem the fit was good and airflow was perfect. With a few adjustments of the diameter of the stem to match the bands the look was very good and it would provide a great smoke. I started the adjustments to the diameter with a folded piece of 220 grit sandpaper. It took a lot of sanding to get the flow of the stem and band correct but it was starting to look very good. I removed the stem and fine tuned the flow of the decorative band on the stem with 220 grit sandpaper. It was really beginning to look very good at this point.I sanded the stem with 320-3500 grit sanding pads. I wiped the stem down after each sanding pad with a damp cloth to remove the sanding debris. The stem began to take on a rich shine.I polished the stem with micromesh sanding pads – dry sanding it with 1500-12000 grit pads. I wiped it down after each sanding pad with a cloth impregnated with Obsidian Oil. The stem looked very good. Before I turned to work on the bowl as a whole I took time to clean out the shank, mortise and the airway in both the shank and the new stem. The shank was very dirty and the airway was clogged. I used a straightened paper clip to poke through the clog and break it up. The airflow is great now.I now turned my attention to the bowl. I wiped down the bowl with acetone to remove the shine varnish coat from the surface. It looked much better and with sanding and polishing would look very good. I used a folded piece of 220 grit sandpaper to clean up the inner edge of the rim and to sand out the darkening on the rim top. It looked better but there was more to be done.I sanded the bowl with 320-3500 grit sanding pads to further smooth it out and remove the nicks and scratches in the briar. The bowl was progressing in smoothness and beauty. I polished the briar with the nine micromesh sanding pads – dry sanding with 1500-12000 grit pads. I wiped the bowl down with a damp cloth after each pad. The bowl took on a rich shine. I rubbed the bowl down with Before & After Restoration Balm. It is a paste/balm that works to deep clean the finish, enliven and protect the briar. I worked it into the briar with my finger tips to make sure that it covered every square inch of the pipe. I set it aside for 10 minutes to let it do its work. I buffed it with a cotton cloth. The briar really began to have a deep shine. The photos I took of the bowl at this point mark the progress in the restoration. I put the Duncan Hill Aerosphere Pot Bowl and the new stem together. I polished the bowl and stem with Blue Diamond to polish the briar and the vulcanite. I gave the bowl multiple coats of Conservator’s Wax and the stem multiple coats of carnauba wax. I buffed the pipe with a clean buffing pad to raise the shine. I hand buffed it with a microfiber cloth to deepen the shine. The pipe polished up pretty nicely. The original brown stains worked amazingly well with the polished vulcanite taper stem. The grain around the bowl and shank and looks quite remarkable. This is truly a beautiful Duncan Hill Aerosphere. The finished pipe is shown in the photos below. The dimensions of the pipe are Length: 6 inches, Height: 1 ½ inches, Outside diameter of the bowl: 1 ½ inches, Chamber diameter: 7/8 of an inch. The weight of the pipe is 1.52 ounces/42 grams. This is such a unique shape that I am going to enjoy it for awhile before deciding what to do with it. Thanks for walking through the restoration with me. Cheers.

A Rebirth for a pair of Duncan Hill Aerosphere Pipes

1 Reply

Blog by Steve Laug

The last pair of pipes needing refurbishing from my gift box was a pair of Duncan Hill Aerosphere pipes – one a smooth pot and the other a rusticated billiard. I have had quite a few Duncan Hill pipes over the years and sold some, restemmed others without the reverse tenon system and really never paid much attention to them. The pot was a nice piece of briar and actually quite clean. The finish was in good shape though dirty. The inserted reverse tenon was loose and would need to be repaired. The bowl was dirty and had some pieces of tobacco attached to the walls of the bowl. The rim was in great shape. The stem was oxidized and the round brass carburetor hole was plugged. There was minimal tooth chatter on the stem and no bite marks that would need to be repaired. The stamping was slightly worn in the middle but it still clearly read Aerosphere over Duncan Hill over Ltd. The rusticated billiard was also fairly clean though there was dried wax stuck in the grooves of the rustication. The rim top was quite dirty with tars and oils built up and filling in the rustication. The bowl had a light cake and tobacco leaf stuck on the bowl sides. The finish was workable but dirty. The stem was in better shape than the one on the pot. It was dirty and had sticky tape remnants on the top but there was little oxidation and no tooth chatter. The carburetor on this one was also clogged and the stem was loose on the reverse tenon. It was stamped with the same stamping as the smooth pot but on a smooth band on the bottom of the shank.

I removed the stems and put the bowls in my alcohol bath to soak for a while. While they were soaking I wanted to do a bit of research on the brand and see what I could discover about it. I was curious to look for patent information and old advertisements to see if I could discover the marketing schemes that made this quite a prolific seller over the years. I Googled Duncan Hill Aerosphere and the first bit I found was from a Google group for ASP. There I found the following quote. I have the reference link placed at the end of the quote if you want to follow up on the information: “The Duncan Hill Aerosphere smoking system (U.S. patent #4,275,747) utilizes the same principle of physics as the manometer. The Aerosphere, visible as the brass pin on the side of the mouthpiece, brings a scientifically measured amount of air into the stem with each puff. The control of the amount of air and the velocity of the air produces two effects that result in superior smoking pipe performance.” https://groups.google.com/forum/#!topic/alt.smokers.pipes/GUxdN5Dus4Q

I love finding this old information and reading about the persistent search for the dryer cooler smoking pipe that has led to many creative solutions. It lends some colour to the work of my refurbishing to be able to read about the design ideas and the inventors themselves as I work on the pipes. Armed with new information I worked on the stems while the bowls were soaking in the alcohol bath. I cleaned the inside and outside of the stems with 99% isopropyl alcohol on cotton swabs and pipe cleaners. It took some scrubbing to clean out the grime built up around the interior of the carburetor insert in the stem and in the second chamber below the airway in the stem. The tars and oils were built up in there but far less so than I would have expected on these pipes from the 1980s.

With the stems cleaned and the carburetor air hole opened in both of them with a dental pick it was time to take the bowls out of the alcohol bath and begin to work on them. I dried off the bowls and pulled the loose reverse tenon out of the shank of the pot. I cleaned the shank with alcohol, cotton swabs and pipe cleaners then pressed the loose piece back in place. Once the alcohol evaporated the fit was tight. I cleaned the shanks on both pipes until the pipe cleaners and swabs came out white.

By the time I finished cleaning out the shanks the bowls had dried enough to ream them with the PipNet reamer. I cut back the cake in the billiard to the bare wood and cleaned up the light cake in the pot. In the photo below the wall of the billiard on the left looks damaged. I used a slightly larger reaming head and took back the remaining cake until the wood was clean and solid. Then it was time to work on the stems. I did a rough sand with 220 grit sandpaper to remove the sticky build up on the darker of the stems and to break up the oxidation on the other one. I followed that by sanding them both with a medium and fine grit sanding sponge.

I put them on the pipes to have a look at the progress of the restoration. I buffed the stems with red Tripoli and worked on the stubborn oxidation on the one stem. I then buffed it with White Diamond. I took them back to the work table and sanded them with micromesh sanding pads – wet sanding with 1500-2400 grit pads and dry sanding with 3200-12,000 grit pads.

I rubbed the stems down with Obsidian Oil and when it had been absorbed I buffed the stems with Blue Diamond plastic polish. The oxidation still showed on the one stem so I started again and sanded it with the medium and fine grit stem and repeated the process through the micromesh and buffing until I had conquered the oxidation.

I buffed the stems with Blue Diamond once again and gave them multiple coats of carnauba wax. I buffed the smooth bowl with carnauba and a soft flannel buff. I stained the rusticated bowl with dark brown aniline stain diluted 1:2 with isopropyl alcohol and then buffed it with White Diamond. I finished that pipe with several coats of Halcyon II wax. The finished pipes are shown in the photos below.