Making an acrylic stem copy

I got in a Radice Rubino with a damaged oval stem. I wanted to try my hand at making a copy in acrylic rod stock using my newly acquired Jet lathe.

The original stem had 3 stress fractures that I repaired used Stewmac 10 superglue. It has a 5 second cure time but is thin enough to fill the thinnest cracks, if you work fast. After drying, I sanded and buffed. The cracks are slightly visible but stable.

I was told to repair that stem or make a new one. I did not have an oval stem blank that large but I did have a black acrylic rod! I chucked it in the 3 jaw chuck on the lathe. First I used a Forstner bit to face it up. Then I drilled a 5/16 mortise in the end about 1/2″ to accept the delrin tenon. Followed that with a 5/32″ long bit to drill the airway to about an inch from the end. Then a 1/16″ long bit to pierce the end. I inserted the delrin tenon, flipped it over to create a slot with my dremel wheel. Funneling it down to meet the 5/32 airway with the slot tool, files and sandpaper.

The fit was light tight against the shank.

I used the 1×30 belt sander to cut down a bit end chunk and shaped the bit and bite area. Also worked the rough oval shape.

While working the button, it fell about 8″ and chipped off a large portion!

After measuring, I ground down the old bit. Using files, I was barely able to cut a new button.

Using my belt sander i created the double saddle stem.

I used the dremel sanding drum to cut in the curves and smoothed with sandpaper. I sanded my stem and matched the shank with files to shave off the last excess acrylic. More sanding, a bend and it’s done.

I’m amazed at how its almost an exact copy of the original. Putting in the dots will have to wait for another project. Oh yeah, it took 12-16 hours!

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A humbling cracked shank reconstruction

I got in a Tinsky pipe with a cracked oval shank. The top and bottom of the shank was too thin to survive pulling the stem out warm I guess. Instead of banding it, I decided to put a brass sleeve inside the shank. A band would have covered a lot of the nomenclature.

Here’s where the restoration went off the rails. I wanted to glue the shank cracks before I started with the tube insertion. I put the tip of the tenon in the shank and gave it a slight flex to open the crack a hair more while applying some 10 thin glue from Stewmac. This has supposedly a 5 second dry time. Needless to say it froze the tip of the tenon in the shank while sealing the cracks on top and bottom.

So, I just created a whole new batch of work for myself!

Having to cut off the tenon resulted in a new tenon needing to be put in. I hand drilled the old tenon pieces with progressive sizes of chucking reamers in the stem and shank after cutting them flush. I put a piece of brass tubing on a dowel, chucked it in my lathe and reduced the outside diameter to wafer thin with sandpaper. Turning to the stem, while reaming it larger, the star logo fell out. I turned down a piece of delrin with the tenon turning tool to fit in the tube. Then I flipped it over and turned down the side going in the stem. I had to make a dozen attempts before I got both ends sized correctly. Various mishaps made me do it over and over. I funneled both ends of the tenon with the countersink tool.

Now was time to assemble everything with G Flex 655 epoxy, which takes 24 hours to cure like steel. I roughed up the stem side of the tenon and inside the stem with a dremel bit for the epoxy to physically lock together. I applied some epoxy inside the shank and the outside of the brass tubing which I CAREFULLY inserted into the shank. I then applied some epoxy inside the stem and put the tenon in the shank, stem on the tenon and wiggled it around for a tight fit. I also glued the star back in at the same time. Then I taped it up and let it sit overnight.

After removing the tape, the stem was slightly off center left to right. Enough that I had to massage the fit with sandpaper and touchup the stain.

I then saw there was still some crack visible and the slightest nick on the mortise.

I reapplied glue sparingly and sanded down when dry. Another stain touchup and a run through the buffing wheels. After an intense prolonged battle, I won! The cracks are NOT visible and the tenon fits sweetly in the shank! The pipe is ready for service without a band to change the look of it. If it hadn’t of been for my slip up with the glue, it would have been a lot easier!

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