Results 1 to 9 of 9
  1. #1
    Join Date
    Sep 2004
    Location
    Dardanup W.A.
    Age
    72
    Posts
    331

    Default Norman Patent tool post. Advice needed please

    Inspired by Barron John's build of the Norman Patent QCTP, I have commenced a build of my own.
    Because my lathe has a rather large distance between the top of the cross slide and the centreline of the lathe, I need to build a pretty solid rigid post.
    Just happened to have laying around the w'shop a piece that might lend itself nicely.

    It is a piece of steel shaft 45mm diam. with what appears to be a pressed on flange which is welded in a machined cavity under the flange. The flange is 15mm thick, 85mm diam.

    Question 1. Will that likely be rigid enough, or do I need a thicker base/flange?
    Question 2. If the above will be adequate, I am thinking of turning the bottom of the flange out to a depth of about 0.25mm, to about 5mm from the outer edge, so that when the flange/base sits on the cross slide, it will be only contact on the outer 5mm.
    The shaft/post will be bored out for a centre bolt, into a "T" nut which will fit the cross slide "T" slot. Tool positioning will be achieved by rotation of the whole unit when the centre bolt is loosened.
    I hope that all makes sense. Cheers.

  2. #2
    Join Date
    Jul 2016
    Location
    Melbourne
    Age
    35
    Posts
    1,522

    Default

    Depending on how you are holding it down and on how flat your compound is you met be better with full contact rather than a ring, you will lose some rigidity with point contact. (Defining how much, or how susceptible to harmonics it will be required more brain than I have)

  3. #3
    Join Date
    Sep 2012
    Location
    York, North Yorkshire UK
    Posts
    6,438

    Default

    Hi Phill, Guys,

    Quote Originally Posted by ptrott View Post
    Inspired by Baron John's build of the Norman Patent QCTP, I have commenced a build of my own.
    Because my lathe has a rather large distance between the top of the cross slide and the centreline of the lathe, I need to build a pretty solid rigid post.
    Just happened to have laying around the w'shop a piece that might lend itself nicely.

    It is a piece of steel shaft 45mm diam. with what appears to be a pressed on flange which is welded in a machined cavity under the flange. The flange is 15mm thick, 85mm diam.

    Question 1. Will that likely be rigid enough, or do I need a thicker base/flange?
    Question 2. If the above will be adequate, I am thinking of turning the bottom of the flange out to a depth of about 0.25mm, to about 5mm from the outer edge, so that when the flange/base sits on the cross slide, it will be only contact on the outer 5mm.
    The shaft/post will be bored out for a centre bolt, into a "T" nut which will fit the cross slide "T" slot. Tool positioning will be achieved by rotation of the whole unit when the centre bolt is loosened.
    I hope that all makes sense. Cheers.
    You don't need the flange ! Once the post is securely fastened to the top slide it doesn't need to move, ever !
    All the hight and rotation is done using the tool holder. About a quarter of a turn on the securing bolt that is pulling the split collet together will lock the tool block solid.

    My post is 32 mm diameter ! Obviously you need to scale things up or down to suit your lathe. A 45 mm post will be like the rock of Gibraltar.

    Original post.
    https://metalworkforums.com/f303/t20...orman+Toolpost
    Best Regards:
    Baron J.

  4. #4
    Join Date
    Sep 2004
    Location
    Dardanup W.A.
    Age
    72
    Posts
    331

    Default

    Quote Originally Posted by BaronJ View Post
    Hi Phill, Guys,

    You don't need the flange ! Once the post is securely fastened to the top slide it doesn't need to move, ever !

    My post is 32 mm diameter ! Obviously you need to scale things up or down to suit your lathe. A 45 mm post will be like the rock of Gibraltar.
    I need the new tool post to have a large footprint, similar to the original in area, because it cannot be fixed to the cross slide due to the fact that I need to be able to turn from the rear (in reverse) and from the front. This lathe has much more room and travel to turn large parts behind the spindle.

    The green tool post shown here has a 90mm X 90mm footprint to give the rigidity needed because it is so tall.
    The flange on the proposed new one (in the chuck) is a bit smaller in area, which is my main concern.

    IMG_20200123_181529.jpg

  5. #5
    Join Date
    Sep 2012
    Location
    York, North Yorkshire UK
    Posts
    6,438

    Default

    Hi Phill,

    Thankyou for the picture ! You know, thousand words...

    I would be using the "T" slot right at the front of the cross slide. I would also put a peg in the bottom of the post to engage with the cross slot. No way it can turn then when tightening the post down. The down side is of course that you won't be able to just loosen the securing bolt and slide the post out.

    If you do use the flange, make the face flat and if desired cut it down so that it doesn't foul the feed handle.

    Now since you don't have a top slide it might be prudent to make a second tool block or just a thick ring that you can use to set the hight from.

    On my rear tool post I just use a piece of scrap that I put on the cross slide and under the block to set the hight and then remove it till the next time.
    Best Regards:
    Baron J.

  6. #6
    Join Date
    Sep 2004
    Location
    Dardanup W.A.
    Age
    72
    Posts
    331

    Default

    Quote Originally Posted by BaronJ View Post
    Hi Phill,

    Thankyou for the picture ! You know, thousand words...

    I would be using the "T" slot right at the front of the cross slide. I would also put a peg in the bottom of the post to engage with the cross slot. No way it can turn then when tightening the post down. The down side is of course that you won't be able to just loosen the securing bolt and slide the post out.

    If you do use the flange, make the face flat and if desired cut it down so that it doesn't foul the feed handle.

    Now since you don't have a top slide it might be prudent to make a second tool block or just a thick ring that you can use to set the hight from.

    On my rear tool post I just use a piece of scrap that I put on the cross slide and under the block to set the hight and then remove it till the next time.
    John, the existing tool post T nut sits up above the top face of the cross slide, by about 5mm, and the buttom of the tool post has a slot cut in the left and right bottom edge into which the T nut fits to prevent rotation of the post. (The T nut is 90mm long)
    That should work for the base of the new post also?? I was going to try to use the existing T nut and post centre bolt if possible, so that I have the option of using the original setup if required.
    I still haven't got my brain around that split collet on your tool holders yet.

  7. #7
    Join Date
    Sep 2012
    Location
    York, North Yorkshire UK
    Posts
    6,438

    Default

    Hi Phill,
    John, the existing tool post T nut sits up above the top face of the cross slide, by about 5mm, and the buttom of the tool post has a slot cut in the left and right bottom edge into which the T nut fits to prevent rotation of the post. (The T nut is 90mm long) That should work for the base of the new post also??
    Yes it will ! Though it makes the "T" nut a special. Normally the "T" nuts don't come above the table surface. If anti rotation is needed a peg is commonly used.

    I was going to try to use the existing T nut and post centre bolt if possible, so that I have the option of using the original setup if required.
    That is fine, I don't see a problem with doing that. After looking at your picture, I thought that you might be going to use the first slot with a tall post. It looks like you loose a lot of table length with the existing arrangement.

    I still haven't got my brain around that split collet on your tool holders yet.
    The penny will drop
    Best Regards:
    Baron J.

  8. #8
    Join Date
    Sep 2004
    Location
    Dardanup W.A.
    Age
    72
    Posts
    331

    Default

    Quote Originally Posted by BaronJ View Post
    Hi Phill,

    Yes it will ! Though it makes the "T" nut a special. Normally the "T" nuts don't come above the table surface. If anti rotation is needed a peg is commonly used.

    That is fine, I don't see a problem with doing that. After looking at your picture, I thought that you might be going to use the first slot with a tall post. It looks like you loose a lot of table length with the existing arrangement.
    This is the setup, and the post & nut I hope to use.
    IMG_20200124_094018.jpgIMG_20200124_093750.jpg

  9. #9
    Join Date
    Sep 2012
    Location
    York, North Yorkshire UK
    Posts
    6,438

    Default

    Hi Phill,

    No problem, just bore your post to fit the existing stud. Make your tool block to suit the new post.
    Make sure that you have enough material to hold the tool size you want to use between the tool and post, and thick enough not to distort when tightening the nip screws onto the tool.

    My tool holders are 1" inch thick with a cutout to hold a 1/2" tool (13 mm).

    I've just looked at my pictures and realised that I've not rounded off the back edge of the rear tool block
    Best Regards:
    Baron J.

Similar Threads

  1. Norman patent rear tool post.
    By BaronJ in forum METALWORK GENERAL
    Replies: 19
    Last Post: 1st Aug 2019, 06:23 AM
  2. Advice needed
    By Twisted Tenon in forum METALWORK GENERAL
    Replies: 3
    Last Post: 13th Nov 2012, 11:06 PM
  3. Parting tool mounted on rear tool post advice needed
    By colbra in forum METALWORK GENERAL
    Replies: 17
    Last Post: 12th Feb 2012, 02:49 PM
  4. Some advice needed for new MIG Pls
    By johncar in forum WELDING
    Replies: 14
    Last Post: 11th Feb 2011, 02:16 PM
  5. Advice needed
    By scanfor in forum WELDING
    Replies: 3
    Last Post: 23rd Feb 2010, 06:25 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •