reggie_obe wrote:Three points, three studs on the table become the locating points, the basics of fixturing. But I'm sure you know that, so repeat-ability is ensured for the "production" run of two parts.
Yes, I know that, and is the precise type of setup I make when required. Placement of the location "studs" can be a problem, however. It's not always easy to clamp the locating pieces in such a location that the work holding clamps are well placed. That would be true for small parts, as, once the locating blocks/studs are placed, there may or may not be room for work holding clamps. That has always been an issue for me, and I expect it would be for seal killer as well.
Don't dismiss the concept of small production (two parts). What is being overlooked is that once a good part has been produced, the likelihood that a second part turns out properly is enhanced, assuming the operator makes what could be construed as a production type setup (recording dial settings is very much a part of that concept). This is the very type of work in which I was engaged (when not building tooling), and never used a DRO. It was routine for me to crank out fewer than ten parts, often with a large number of features, and do so without creating questionable quality. I attribute that to the very idea of making simple setups and recording dial settings. It takes far less time to do that than to start from scratch on each piece.
Here's a good example of work produced by that very method. Take note of the huge number of features, some nested within other features. Close tolerance work, all produced without making scrap. The copper pieces are 1¼" sweat couplings, which should serve to help in a size perspective of the work piece. It's ¼" thick aluminum, alodine finished.
I would not remove and remount my vise for two parts. No production shop would and not necessary for producing two parts in a hobby shop either.
Unfortunately, I missed your point. Whether it's remounting a vise, or making a table setup, effort must be expended. I, personally, would opt for the one that offered the greater advantage, and in this circumstance, it would appear to me that a vise would. Clamping parts to the table is slower, and offers a small, although more likely, risk of error. And making the table setup would still require the removal of the vise, as well as the reinstallation of the vise. There is no time loss that wouldn't be lost, regardless of choice.
Harold