I regularly operate 3 Machines 2 mills and a saw making production parts Paid Piecework, I'm very very fast, thus well paid , but all the Machines have auto stops for the feeds, or I could not do what I do. the tiniest distraction would be the end of a machine or at least tooling V/r HT1
Yes that's it exactly. As seen in the 2nd picture the part was originally made with plenty of travel so it doesn't necessarily have to extend off the base. But the dovetails are so boogered and the toolpost holder t-slot so bent that the gib had to be removed in order to get it in that position. It seems very unlikely that I will use the lamppost. I'll be getting a quick change setup for it. I have both styles for my SB9 and the lamppost stays in the drawer except when I'm parting aluminum. Just for reference the material thickness immediately under this t-slot is .250" and the dovetail is an additional .350". It's pretty clear to me how the casting broke in the first place and it was probably never up to the task again after that, but that break really doesn't concern me to much. As has been suggested, even if it's not the strongest original design it should hold out just fine in the new casting. My original question was more about the overall shape of the main body of the casting and how it transitions to the t-slot member. (Curved body and radius'ed to the t-slot). I was wondering aloud if that radius feature was meant to enhance the strength of that side of the T or, as ESC suggested, maybe that's just the way they made them. All of the searching of old lathes I've done shows some form of support for that side of the T-slot in the casting so I'll go ahead and modify the wooden pattern with a curve and a radius to at least approximate the original.
Here are couple pics of my 1943 EE compound T-slot. It’s width is not too wide for a modern QCTP. Since it was designed in the 30’s, the engineers that drew it were not computer jockeys and must still have had some clue about good design. The slot on the compound you at showing is maybe 2” wide? I guess you’ll span the slot and raise the toolpost with a very thick washer? I like the radius idea, for sure. Denis
The part from the lamp post which fits the slot measures 1.739". I'll have to look at my options for the QCTP but I have to cut the slot so that my lamp post will still fit. So yeah, I'll probably end up making a bridge/elevating piece. The QCTP I have on my SB 9 might fit. I'm sure I'd have to elevate that one. The original lamppost is pretty darned tall compared to the little one from the south bend. Pete
