Readers of this blog will know that it is unusual for me to admit defeat. Usually, I will doggedly pursue an idea until everyone has pretty much drifted off to cat videos, except for a few readers who check back to shake their heads and mutter such things as “he had so much promise.” However, after two containers and countless attempts at creating gaskets to … Continue reading Wanted – pressure vessel
A couple of weeks ago, as I was setting up to demonstrate at VTE, I realized I didn’t have anywhere for my puddle of glue. I normally use an old CD for this purpose, and for years AOL provided me with an almost monthly supply. I still have a lifetime of CDs ready to receive globs of paint or glue, but they may never get … Continue reading Necessity invents a palette
The past couple of weeks have been all Christmas gifts all the time, but tonight I finally managed to get few minutes to spend on my projects. With the heavy shop out of action until we rebuild from the flood, I’m reduced to the crowded garage floor for heavy shop work. I’m still working toward a pressure vessel for casting, and I came across a … Continue reading Perfidious air
I’m still grappling with the problem of bubbles in my castings. The accepted wisdom indicates that you want to set polyurethane castings under pressure so the bubbles become very small. I think the Smooth-on site suggests 60 psi (413 Kia). Not having anything that holds pressure, and not wanting to spend a lot of money, I took a trip down to the local Sally Ann … Continue reading A good effort at pressure
My first plastic vacuum chamber for evacuating rubber Moldavia never held much pressure. For this attempt, I poked around at the local thrift store and ultimately came away with a pot and a tempered glass lid that will enable me to see what is going on inside. Until I got hold of it, there was absolutely nothing wrong with this pot; I’m certain it had … Continue reading Vacuum chamber
It’s hard to believe, but I bought this vise at the same garage sale where I got my drill press for fifty bucks fifteen years ago. For a lifetime, the drill press and vise had been part of a piano repair business, but even in 2003 nobody wanted real pianos anymore, and even fewer wanted repaired ones. I think he threw in the vise for … Continue reading Unused tools
I’ve been experimenting with OnShape sheet metal models to produce patterns for etching parts. Being designed for ordinary bending processes, OnShape is not directly applicable, but I think it is close enough for my purposes. Here are the sheet metal model parameters that I have found work in OnShape to produce drawings that match the recommendations for etching. Thickness = material thickness Bend radius .0004″ … Continue reading Using OnShape to create etching patterns in InkScape
