Glass model steam engine - video

[Jon]

Glass model steam engine. 2:16 video:

Previously:

working paper engine models
steam-powered model sawmills
1872 steam-powered hop digging machine - photo, patent
World land speed record-breaking steam car - video and photos
Steam-powered machine shop
Steam shovel GIF
Scale model working Lombard Steam Log Hauler build
Lombard steam log hauler
Steam-powered submarine
1901 steam-powered lawnmower
Hornsby mammoth steam crawler tractor
1900 restored Fowler steam traction engine
Steam-powered tanks
Steam locomotive drag racing

[mklotz]

The thing that amazes me the most is how he managed to fit the small end of the connecting rod around the gudgeon inside the piston and still maintain a movable joint with little backlash.

[Frank S]

Absolutely amassing display of glass blowing skill. Marv you're an accomplished model builder. In your opinion what would the be scale of difficulty in making the valve and its components without the use of a precision lathe if you were to try an make them out of any type of metal let alone having to deal with any material as fragile and as hard as glass?
I've watched several accomplished glass blowers and artisans make beautiful figurines vases long tubes and many other things but never anything like this.

[mklotz]

Well, the sans lathe techniques would be entirely different for metal than what I would imagine for glass.

The valve piston is probably a standard size glass rod. Perhaps the valve body is blown around a suitably sized metal former to produce a bore that's close to the OD of the valve piston. All glass (body and piston) hypodermic syringes are common (I have several) so a good seal is certainly possible.

Another possibility is heating and pulling a glass cylinder until it's the right OD and then cutting a section out of it. Of course, the reverse of the procedure is possible - standard size tubing and heat-pull rod to make a piston to fit.

These are only guesses on my part, though. My total experience with practical glass blowing was making an ionization chamber for a physics lab in college. It wasn't near the complexity of this and, of course, had no moving parts.

[Frank S]

I hear you Marv, Mine was a brief stint in a chemistry lab my professor and I with help if you want to call it that from a few others, made an all glass 4 stage still we made coils out of glass tubes expanded and reduced their diameters welded them together and made bubbling chambers. I have to say my involvement was mostly breaking things but I could at least join 2 tubes and form coils.

[Jon]

Turns out this is quite the build! Has its own website: Glass Steam Engine - steamglass.com . This piece sold on eBay for $1,525.

[mklotz]

The more I look at that thing the more I think that cylinder looks exactly like a cut-down hypodermic syringe. Commercial glass syringes have that same finely ground appearance on the inside (and on the piston that fits it) and a similar rolled edge at the top.

I certainly don't want to demean the fine work of this craftsman but, if I were to set out to build a glass steam engine, I know I would first start looking for a syringe. For obvious reasons, syringe pistons fit tightly so, to relieve the piston-cylinder friction, a bit of honing would have to be done on the piston. I still have no idea how he managed to get the gudgeon inside the piston and attach the connecting rod.

Just in case you're wondering why glass syringes still exist...

My once-obstetric-nurse daughter tells me that the doctors like to use them when administering an epidural during delivery. They say that they get a better "feel" for where they are in the spinal column with the feedback from a glass syringe.

My guess for why this may be true goes like this...

Plastic syringe pistons have a rubber-like tip which acts as a seal. This might lead to a tiny bit of stiction that wouldn't faithfully transmit the back pressure from the spinal fluid. Glass syringes have no such seal and could thus be more responsive.

[mklotz]

Turns out this is quite the build! Has its own website: Glass Steam Engine - steamglass.com . This piece sold on eBay for $1,525.

$1525 is way too little. Now you know why model engine builders seldom build to sell. At, say, 80 hours to build (a conservative estimate), that's $19 an hour for highly skilled labor.

Last night, on Antiques Roadshow, I saw an unremarkable 8 x 12" landscape painted on a cigar box lid appraised for $100,000. There's no justice.

[olderdan]

Could not agree more, I sometimes help out a fellow motorcyclist with a bit of machining and just say give me what its worth to you as I cant charge what its cost me to do the work.
Skills have never been valued much in the UK

[Frank S]

When I first got back from kuwait I had a job that really needed 2 welders to complete in a reasonable time frame. The place next door to me used a lot of contract rig welders so I hired 1 of them He told me for call outs he charged $75.00 an hour plus travel but the company next door only paid $50.00 per hour with 4 hour minimum I told him 540 was fine if he was worth it. after about 4 hours I had to tell him that I really thought I could finish the job faster by myself. I gave him $250.00 for his troubles but personally thought he had only done about 150 worth of work When my costumer picked up his machine and asked me how much, after I told him. He said man that's less than you charged me for a job just like this one 20 years ago so he handed me 500 more than I had told him.
For that glass steam engine if I wanted one I would easily have paid a lot more than it sold for