SS Lathe and the 1963 Yuba Court Case

[pennview]

I had read about this case some time back and how it had found it's way in case law. Basically, the guy was injured using the Shopsmith as a lathe when the tubes came apart. He claimed it was unsafe as designed and that Yuba's literature touted the machine's safety and ruggedness. Yuba's literature stated (1) "When Shopsmith is in Horizontal Position--Rugged construction of frame provides rigid support from end to end. Heavy centerless-ground steel tubing insures perfect alignment of components." (2) "Shopsmith maintains its accuracy because every component has positive locks that hold adjustments through rough or precision work."

There is loads of information about the case on the internet. Some details about case in question can be found at the Tool Hunter website: http://sites.google.com/site/thetoolhun ... bility-law

[ddvann79]

...Some details about case in question can be found at the Tool Hunter website: http://sites.google.com/site/thetoolhun ... bility-law

Thanks, Art. That's one place I didn't think to look. All my searches brought up briefs and business law textbooks. Seems plausible that the issue was the tightness of the tubes in the base. So are there parts out there to decrease the likelihood of those set screws coming loose? Blue Loctite comes to mind. Anything else?

[pennview]

Since they're still using screws to hold the tubes in place, I'd expect that the tolerances were adjusted for a tighter fit of the threads so that the screws won't back out from the vibrations. That said, the lathe function among the various Shopsmith functions is the most likely to introduce the possibility of considerable vibration depending on the size of the stock you're using or how it's mounted, so using one of the Loctite sealants should ease any concerns about the screws backing out.

[pennview]

Since they're still using screws to hold the tubes in place, I'd expect that the tolerances were adjusted for a tighter fit of the threads so that the screws won't back out from the vibrations. That said, the lathe function among the various Shopsmith functions is the most likely to introduce the possibility of considerable vibration depending on the size of the stock you're using or how it's mounted, so using one of the Loctite sealants should ease any concerns about the screws backing out.

[dusty]

Since they're still using screws to hold the tubes in place, I'd expect that the tolerances were adjusted for a tighter fit of the threads so that the screws won't back out from the vibrations. That said, the lathe function among the various Shopsmith functions is the most likely to introduce the possibility of considerable vibration depending on the size of the stock you're using or how it's mounted, so using one of the Loctite sealants should ease any concerns about the screws backing out.

I've only done this three times but when you dismantle a Mark V to the point where you can remove the way and bench tubes, I think you will come to the conclusion that this lawsuit was also based on weak conclusions. For the way tubes to move that much, the bench tubes also must spread apart. Not likely to happen unless assembled wrong.

To make my point, loosen the setscrews on the tie bar and pull the tie bar off the ways about 1/4" and then put the unit back in horizontal position. It won't go.

The base, headrest, tie bar and tubes fit together in what I consider a very sound package. Even with loose set screws, the headrest and base assemblies have very little room in which to move.

[JPG]

We do not know how the tailstock center was being used(if indeed it was) since the project was to turn a chalice.

I would not attempt to turn one without a chuck(not a spur center etc.). I doubt the 'victim' had one!

[pennview]

It's hard to understand all of the specifics about a case that occurred in the 1950s, but by all accounts Mr. Greenman was injured. Here's some of the information I found regarding what happened back then.

"Plaintiff brought this action for damages against the retailer and the manufacturer of a Shopsmith, a combination power tool that could be used as a saw, drill, and wood lathe. He saw a Shopsmith demonstrated by the retailer and studied a brochure prepared by the manufacturer. He decided he wanted a Shopsmith for his home workshop, and his wife bought and gave him one for Christmas in 1955. In 1957 he bought the necessary attachments to use the Shopsmith as a lathe for turning a large piece of wood he wished to make into a chalice. After he had worked on the piece of wood several times without difficulty, it suddenly flew out of the machine and struck him on the forehead, inflicting serious injuries. About 10 1/2 months later, he gave the retailer and the manufacturer written notice of claimed breaches of warranties and filed a complaint against them alleging such breaches and negligence.

"Plaintiff introduced substantial evidence that his injuries were caused by defective design and construction of the Shopsmith. His expert witnesses testified that inadequate set screws were used to hold parts of the machine together so that normal vibration caused the tailstock of the lathe to move away from the piece of wood being turned permitting it to fly out of the lathe. They also testified that there were other more positive ways of fastening the parts of the machine together, the use of which would have prevented the accident."

[ddvann79]

We do not know how the tailstock center was being used(if indeed it was) since the project was to turn a chalice.

I would not attempt to turn one without a chuck(not a spur center etc.). I doubt the 'victim' had one!

If indeed the issue was with the tailstock moving away from the rest of the machine, it could simply be a way to reference the machine generally coming off the tubes. It could be that the tailstock end is what slipped. It could also be that the tailstock was being used to turn the chalice if he was roughing it in and had not starting end turning yet.

SO ARE THE SET SCREWS USED TODAY ANY DIFFERENT FROM THE ONE'S IN THE 50'S, ESPECIALLY PERTAINING TO THE TUBES? Surely someone with a vintage SS and a new SS can answer this question. I know some of the set screws I have ordered were not the same as the ones I was replcaing but I haven't ordered any for the tailstock eccentric or the tubes.

[dusty]

If indeed the issue was with the tailstock moving away from the rest of the machine, it could simply be a way to reference the machine generally coming off the tubes. It could be that the tailstock end is what slipped. It could also be that the tailstock was being used to turn the chalice if he was roughing it in and had not starting end turning yet.

SO ARE THE SET SCREWS USED TODAY ANY DIFFERENT FROM THE ONE'S IN THE 50'S, ESPECIALLY PERTAINING TO THE TUBES? Surely someone with a vintage SS and a new SS can answer this question. I know some of the set screws I have ordered were not the same as the ones I was replcaing but I haven't ordered any for the tailstock eccentric or the tubes.

Of the set screws that mate with the tubes (way and bench) all of mine are serrated. Two different vintages but both newer than the plaintiffs.

[ddvann79]

Of the set screws that mate with the tubes (way and bench) all of mine are serrated. Two different vintages but both newer than the plaintiffs.

Ah Ha! Now we are getting somewhere.

This is what the set screws for my way tubes look like. Any cause for concern? As far as I know, the bench tubes are only held in place with the tube lock bar so it doesn't make sense that set screws would come loose here. Did I also hear someone say the set screws were visible from the top of the tubes?

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