Norton Quick Change Gear Box on Myford Super 7

[tony MoulderParticipant @tonymoulder13093]

[tony MoulderParticipant @tonymoulder13093]

Can anyone help me with a problem that I just do not understand,

I am trying to cut a 10 tpi BSW thread on my Myford Super 7 fitted with the Norton quick change gear box, However rather than the thread starting, what is happening is that a very rough cut is being carried out along the work

I have tried different thread settings but on all occasions I have the same problem.

To my eye it appears that the travel speed ratio between the lead screw and the work in the chuck is out of sinc?

I would be really grateful of any advice please,

Tony

[John Stevenson 1Participant @johnstevenson1]

Have you reversed the compound gear in the train from fine feed into threading mode?

[Brian WoodParticipant @brianwood45127]

Hello Tony,

​Would you describe what you are actually doing please, things like when or how you are engaging the cut, are you using the indicator for example to help with that, cutting under power and at what speed and so on. A picture of the result might also help us here.

Regards
Brian

[not done it yetParticipant @notdoneityet]

As Brian, really.

Does this only occur with 10tpi? Or is it any thread pitch?

[RobboParticipant @robbo]

+1 for John Stevenson's suggestion to try first.

[tony MoulderParticipant @tonymoulder13093]

Hello all and Thank you for all advice,

Must tell you that I am a complete novice with the Super 7, I also have a ML7 for which I get along fine with including screw cutting so I understand the basic principles.

John, Now I am going to sound a real novice now so please forgive my lack of knowledge, please could you explain in simple terms how I go about reversing the compound gear, I do not actually know what this is or indeed where to locate this gear, on looking at the work in the chuck it does actually appear to be cutting a fine thread not the 10tpi I am aiming for.

Brian, I am trying to achieve a 3/4 10tpi BSW thread, Firstly I select the gear ratio and hand turn the head stock, the gearing seems to all fall in place, I am using the indicator coming on the cut at 2 or 4 gear speed set on slow with back gear in off position and I have also engaged the back gear, this make no difference, Best Regards Tony PS Having a problem uploading photos, I will keep trying.PPS Yes in all gears. Thank You

[John Stevenson 1Participant @johnstevenson1]

Away from my computer and only have a phone.

Go to http://www.lathes.co.uk and select Myford from the top menu or the list

In the sub menu that comes up, select Super 7

First page about 3 photos down,RH side is a very clear picture of the gear train and the compound gear in question.

Sorry I can’t be more helpful

[JasonBModerator @jasonb]

[tony MoulderParticipant @tonymoulder13093]

Thank you John, got the info from lathes.co.uk, I now understand, I will try as you advise and keep you posted.

You have been more than helpful, much appreciated.

Tony

[John Stevenson 1Participant @johnstevenson1]

Thanks Jason

[tony MoulderParticipant @tonymoulder13093]

Thank you Jason, all so helpful

[LambtonParticipant @lambton]

Tony,

Please get yourself a manual; for the Super 7..It is absolutely essential reading for a new owner of a Super 7

PDFs of it are available on the net free .

[tony MoulderParticipant @tonymoulder13093]

John,

A massive thank you all now threading perfectly, your knowledge was invaluable,

Lambton, I will do this, thanks

Jason, New owner so the pic was helpful,

Brian, and all, input appreciated,

Great forum.

Best Regards

Tony

[Brian WoodParticipant @brianwood45127]

I'm glad it worked out Tony, JS spotted the obvious and welcome to the Forum by the way, I think we all forgot that.

Regards
​Brian

[tony MoulderParticipant @tonymoulder13093]

Thank You Brian,

New and very inexperienced, I have learnt today,

Due t6o you Guys

Regards to All

Tony.

[steamdaveParticipant @steamdave]

If you are not already a member, consider subscribing to the yahoo group for Myford lathes.
https://groups.yahoo.com/neo/groups/myfordlathes/conversations/messages
You will need to join the group to see all the interesting bits. Lots of useful information, helpful and knowledgeable folk there.

Dave
The Emerald Isle

[tony MoulderParticipant @tonymoulder13093]

Thank you Dave for the information, certainly check this link out,

Best regards

Tony

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