#Gelbart #lecture #video #toread on “limitations of servo systems, introduction to #sensors, and #LVDT”
on 02026-07-27#Gelbart #lecture #video #toread on “choice of filter, grounding, and sampling”
on 02026-07-27#Gelbart #lecture #video #toread on “tellurometers and inductosyn”
on 02026-07-27#Gelbart #lecture #video #toread on “interfacing, filter selection, and types of wires”
on 02026-07-27#video of someone recreating #Gelbart’s bending brake. #manufacturing #toread
on 02026-05-19another #Gelbart #video #toread from the UBC Engineering Physics Project Lab
on 02026-05-17another #Gelbart #video #toread, “solving impossible problems for fun and profit”, by “632nm”
on 02026-05-17apparently a 77-minute #Gelbart #lecture #video: “Summary of Sensors, Limits of Accuracy, and Unusual Sensors, by fizzym” about how digital calipers were originally inductive, switched to capacitive (bad in a machine shop, and also using incremental encoders), and some have now switched back to inductive. Also talks about #Tellurometers, and material stability with time (he says steel and regular invar shift by 1 or 2 ppm in a year) and recommending Rolt’s #metrology book Gauges and Fine Measurements. And how laser microphones bounced off windows work. And how the Russians bugged the US embassy. And nonlinear junction detectors for finding bugs, using a second-harmonic narrowband filter to detect parts per billion of nonlinearity in the reflected signal. And how you detect eyes looking at you by scanning the scene around you with a 10mW 830nm laser and looking for retroreflections a million times weaker (10 nanowatts, a “huge signal” in #optics).
on 02026-05-17#video on recreating #Gelbart’s bending brake #manufacturing
on 02024-09-21#video of #Gelbart mostly about spot welding. He recommends 15–25 kVA spot welders at 2½ volts with 5000 amps, for 1–4 cycles for thin ferrous sheet metal, up to 10 gauge, and up to 12 cycles for mounting hardware like screws or, with a conical-hole electrode, balls for kinematic mounts. I’m guessing a “cycle” is 16⅔ms. Talks about how to spot-weld #nitinol into #flexures. Recommends tungsten/copper or chrome/copper alloy tips for your electrodes. #manufacturing #precision
on 02024-09-21#video of #Gelbart mostly about how to use adhesives, especially silicone, epoxy, polyurethane (e.g., Gorilla Glue), and spray contact cement. Also talks about #flexures for clamping things. And how peeling-mode failure kills adhesive joints, though less so if you use flexible adhesives. #manufacturing
on 02024-09-21Make's coverage of Dan #Gelbart’s #manufacturing videos.
on 02015-08-16The business history of Creo, the more successful one of Dan #Gelbart’s #startups, acquired by Kodak for one Instagram and then declining.
on 02015-08-16Dan #Gelbart explains how his micron-precision metal-#machining #lathe gets its positioning accuracy.
on 02015-08-16Thread on Practical Machinist forums about Dan #Gelbart’s videos, and in particular a #machining centering device he made with a small #laser.
on 02015-08-16Dan #Gelbart’s account on Practical Machinist’s forums. Registration only.
on 02015-08-16countercurrent #heat-exchangers called recuperators are commonly used to recover 70-80% of the exhaust heat to preheat incoming air and fuel in metallurgical furnaces, heat engines including microturbines, and also in #Gelbart’s uniflow #steam-engine. #mecheng
on 02015-08-14Dan #Gelbart’s description of his 2010 #steam-engine. (Or maybe it's Tom Kimmel’s.) Includes a sort of zero-#TCE construction to keep the inside diameter of the cylinder constant: when the 440C stainless-steel cylinder expands, the graphite-filled #polyimide (Vespel) liner tries to expand even more, but can only do so toward the inside of the cylinder, thus counteracting the cylinder’s expansion. The piston itself is made of electroless-nickel-plated #Invar, which really seems like overkill, but whatever. The tabletop model reaches 10% efficiency.
on 02015-08-13#Video of Dan #Gelbart's uniflow #steam-engine #engineering #hardware
on 02015-08-13Dan #Gelbart’s brief autobiography for SPIE.
on 02015-08-12Dan #Gelbart’s brief autobiography for SPIE, focusing on his work at MDA, Cymbolic, and Creo. Substitutes “aerial density” for “areal density”.
on 02015-08-12Discussion of #Gelbart’s very impressive #machining #lathe on HN.
on 02015-08-11