Checking runout

[Brian HParticipant @brianh50089]

I never realised that Tubal Cain was American! The video was very interesting but confused me a little by talking about FOUR adjusting screws when my Grip-Tru has only 3.

[Roderick JenkinsParticipant @roderickjenkins93242]

Posted by Brian Hutchings on 03/02/2016 10:21:11:

I never realised that Tubal Cain was American!

He's an imposter . The "real" Tubal Cain, the well respected writer for ME (and EIM, dare I mention it?) was Tom Walshaw, a Brit.

Rod

[John MilliganParticipant @johnmilligan78347]

Already checked level Mike, this was more a chuck issue which is now pretty spot on once I knew how to adjust it! Think I will have to get a four jaw sometime soon though as I work thru Harold Halls test pieces, John

[Brian HParticipant @brianh50089]

Posted by Roderick Jenkins on 03/02/2016 11:48:08:

Posted by Brian Hutchings on 03/02/2016 10:21:11:

I never realised that Tubal Cain was American!

He's an imposter . The "real" Tubal Cain, the well respected writer for ME (and EIM, dare I mention it?) was Tom Walshaw, a Brit.

Rod

Thanks Rod, I also didn't know that the real Tubal Cain was Tom Walshaw; I really must get out more!

[Neil LickfoldParticipant @neillickfold44316]

My main Griptrue chick is about 30 years old possibly more, the new one is about 20 years old. I have hardly used the new one. I have the outside jaws on the new one and standard jaws on the old one. I just change chucks instead of switching out the jaws. One thing that I thought of when I 1st got the lathe as it came with this chuck, was to adjust the chuck with the least amount of pressure to hold the part true. I think they can be damaged by over tightening the adjuster taper screws. When ever I need to hold something very tight, I use the 4 jaw chuck for that. I rarely need the 4 jaw.Over the range the old chuck is upto 0.05mm tir out. But if zeroed in on a size it is still better than 0.01mm every time. I have not taken it apart for a service yet, but will do after reading the info and articles. Here is a picture of modifying a 6×15 bearing outer race to become a magneto bearing. The bearing is a very light press fit into the fixture with castor oil to allow the over size part to assemble. There is an extractor screw to take out the bearing shell. It was set up in the Griptrue because if the inner race did not run true to the outer race, I could adjust it to be true, then I could turn away the part of the bearing to the race center line. It happened with this bearing that no adjust was required.

[John MilliganParticipant @johnmilligan78347]

Latest update, chuck all adjusted stock bar running about 1 thou out and turned a 6" long by 1" dia test bar and this has 0.0005 runout of parallel over the 6" so am pretty pleased with that. First attempt at grinding my own HSS tools in 30 years and got pretty good finish too, let's hope all the lathe adventures go as well! John

[egaParticipant @ega]

Am I right that no one has mentioned the point made by GHT about Griptru adjustment? He devoted nearly two pages to the subject in his MEs Workshop Manual, the central (!) point being that he counselled easing off and re-tightening the body screws before and after adjustment.

[Neil LickfoldParticipant @neillickfold44316]

Posted by ega on 04/02/2016 17:07:24:

Am I right that no one has mentioned the point made by GHT about Griptru adjustment? He devoted nearly two pages to the subject in his MEs Workshop Manual, the central (!) point being that he counselled easing off and re-tightening the body screws before and after adjustment.

I had a look at my chuck, it has belleville type washers under the cap screws holding the chuck together.

What you say does make sense about the body screws. I have never has any issues with my chuck though.

Glad to hear the OP has found the cure to getting it running well again.

[John MilliganParticipant @johnmilligan78347]

Hi ega, yes I read a write up by Tubal Cain in his book on work holding so I did crack the chuck/backplate bolts before adjusting and then tightened up after, John

[SillyOldDufferModerator @sillyoldduffer]

Posted by Roderick Jenkins on 03/02/2016 11:48:08:

Posted by Brian Hutchings on 03/02/2016 10:21:11:

I never realised that Tubal Cain was American!

He's an imposter . The "real" Tubal Cain, the well respected writer for ME (and EIM, dare I mention it?) was Tom Walshaw, a Brit.

Rod

Sorry to be a pedant but Tubal Cain is in the Bible: he's the first metalworker.

[Roderick JenkinsParticipant @roderickjenkins93242]

Hence the inverted commas. Irony (see what I did there?) doesn't seem to work very well over the intenet

I believe he gets one brief mention in Genesis but Ray Winstone managed to make a meal out of him in the film Noah. Mackay managed to construct a whole poem around him **LINK**

Rod

[SillyOldDufferModerator @sillyoldduffer]

Posted by Roderick Jenkins on 04/02/2016 21:27:49:

Hence the inverted commas. Irony (see what I did there?) doesn't seem to work very well over the intenet

I believe he gets one brief mention in Genesis but Ray Winstone managed to make a meal out of him in the film Noah. Mackay managed to construct a whole poem around him **LINK**

Rod

Mea Culpa Rod. It seems that it's not only our American friends who don't get irony!

I think the Mackay of the poem must also be the author of one of my favourite books – "Extraordinary Popular Delusions and the Madness of Crowds". I like the works of the "real" Tubal Cain too.

Cheers,

Dave

[Roderick JenkinsParticipant @roderickjenkins93242]

Dave,

That Mackay book, I think it must be the same bloke, looks fascinating – just my sort of thing. Now downloaded to my Kindle.

Thanks,

Rod

[Nick_GParticipant @nick_g]

.

The latest incarnation of Tubal Cain has just today posted this video that relates to the OP's question.

Nick

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