what do you call the old style tool post holder which had a single bolt at the top and the lathe tool sat in a slot on top of a big curved thing like a large woodruff key in a curved base which allowed vertical adjustment of the tool tip? and can you still get such a thing. Back when I was playing with lathes many years ago lots of lathes had them and now I can find no reference on the net
"Lantern" or "American", though they have been obsolete here since forged carbon steel bits went out of favor around 1900. They are a good match to "Armstrong" type tool bit holders which are rather tall for other types of tool post.
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On long repetitive jobs the combination allows the bit to be sharpened and replaced with little or no readjustment by sliding it up against the workpiece, but they are a nuisance for hobby work until you learn to estimate center height.
A lantern holder can be made easily from a bolt with only a minimally equipped lathe and a drill press, and sometimes they fit into difficult places when a modern tool post won't, such as very short work between centers where the tailstock base restricts carriage movement.
I bought a spherical washer pair to get the concave ring and fitted the curved rocker that supports the bit by hand, by smoking and filing to full contact. Use a hardened bolt in the top or else it will mushroom and be difficult to remove, as you have to chisel the expanded end off.
Thanks for a bit more of the background on them. I used the lantern toolpost with the Armstrong bit holders on almost all the lathes I used when in the US educational system, junior and senior high, in the late
1970s and early 1980s. The votech school in Wichita used them also, I did that while in high school around 1980-1 as an evening class. The basic votech class required that you learn to grind a 3/8" HSS tool bit before starting on a machine so you then used that bit in the Armstrong holder so it made sense, once you passed the basic class you got allowed into the good workshop and onto the decent machines and I can't recall them using lantern tool posts after that. I do recall the entry machine shop had lots of Rockwell lathes of around 12" swing and the guys running the class, both time served machinists I understand, didn't have anything good to say about them.
I can see where they may have a use but so far I haven't had to do anything on my Harrison M300 that couldn't be done with the Dickson toolpost and holders.
Yes they are nice. I've only used them on one machine which was down the local technical college and it seemed to work really well. The lathe in question was a Hardinge HLV so I guess the question of price of the tool post wasn't much of an issue.
I have a couple of genuine Dickson tool posts and a Bison copy and the tool holders seem to interchange without problems, I haven't tried any of the cheaper copies yet.
Good point about the shaper as I did use them occasionally down the local tech college for doing cylinder heads and similar things but the lantern tool post on them never annoyed the way a lantern tool post did on a lathe, maybe due to the dished wedge not being present.
Maybe an anachronism isn't such on a machine which itself is in many ways an anachronism, not that I would pass up a good shaper if was offered one. I almost bought a nice one years ago but got beaten to it. I have a job I have been asked to do occasionally where a small shaper would be great but it gets done on the BP when asked at the moment.
Just been given an Alba 18" stroke shaper , I'm in the process of rebuilding it now , I'm also on the hunt for any Armstrong /Williams tool holders with a 5/8' thick shank preferably the T series which does not have the back rake built in .
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