hepworth copy attachment missing handle

Hi All

I have a Hepworth copy attachment. However the handle to move the head back and forward is missing. I think its the smallest model they produced 300, and its relatively recent 1986. It differs from the earlier models having quite square body. Do any of you have a similar unit that you could let me have some details of. Its the standard lever that i'm interested in, as I intend to make it. Any help would be appreciated.

Thanks

Hugh

Here are some photos

Are you talking about the bit that goes in the hole next to the roll pin and is clamped by the two grub screws?

This is just a rod that pokes downwards, with the bottom tapped to hold the stylus. The stylus is a hardened triangular piece that bears on the pattern.

It has just struck me that a Vxxx carbide insert, suitably reground, might make a good stylus.

Are you talking about the bit that might replace the square green plate held on with button head screws?

This is the retraction lever. On the top, it is a lever with a knob. It clamps to a vertical shaft. Looks like it has about 60 degrees of travel.

I highly recommend buying a manual as it contains useful advice on using the attachment. It also has diagrams of both pieces described above. My own attachment is buried in the shed somewhere hence the vague reply.

If you give me specific part numbers from the manual, I will measure and draw the pieces for you. Please send me a PM with your email if interested.

The stylus should replicate the shape of the tool being used. Otherwise you will not get faithful copy. In this example the tool is round with a radius of 1.5mm, so the stylus is simply a 3mm diameter spigot:

Andrew

Hi DC31K

No I'm not talking about the stylus its the handle mechanism. I assume this moves the pin on the stylus mounting arm .There would appear to be at least two designs of these units one has the handle mounted on the side like mine the other has the handle mounted on the top. When these were produced the standard option was a simple mechanism operating the pin moving it back and forward with a detent. The other an optional extra was a more complex unit with a dial and various stops as per Andrews picture above. Due to the complexity of the latter I intend to make the simple standard version, unless I can find a second hand spare of the more complex type but this is less likely as the years progress. I do have plenty of instruction for a number of units but not for this one or any pictures.

I think my unit has the lever mounted on the side hence the two threaded holes. The square plate is just a cover to allow tensioning of the bearings.

if you think yours is similar to mine I would very interested to get more info, as for now I cant find a thing on the net showing this square unit all others are rounded.

PS what's a PM did you mean phone number?

Many thanks Hugh

Hi Andrew

Thanks for your reply but I do have much info on these units from lathes .co.uk at what I must say was a bit expensive, but very useful unfortunately not for this units handle.

Anyway on another subject the mounting block on my unit has a narrow dovetail mount from the original fitment. As I was intending to fit a DRO I was thinking of fitting a new machined dovetail block on the top of the cross slide and using this original mount that came with the unit , freeing up the side of the cross slide for the DRO and mounting the bed unit on the front of the bed using the two machined pads, and the reader head on the side of the saddle.

I have a Harrison vs330tr bed wise identical to the M300 you have.

Do you have any comments on this proposal. Apart from drilling holes in the cross slide do you see a down side.

Thanks Hugh

Hugh,

Sorry to side track your thread. I don't suppose you have details of the types of copy attachment hepworth made? I am looking for a unit for my lathe which is smaller than the M300 (10" swing) and has the cross slide drilled and tapped for a "copy attachment". Feel free to PM me as required.

Thanks,

Steve

PM = private message

See the inbox along the top menu bar when logged in.

Andrew

If you look at Swiss Tony's site, it will at least give you a run down of the model numbers. Contribute to his retirement fund and you will get some pictures in the post.

For completeness, here are some other threads on copiers:

On ME forum search:

"Hepworth Lathe copying attachment " by one pound 23/08/16

"Hydraulic copy attachment put into practice" by Chris Richards 3 10/10/15

"Lathe copy attachments" by Chris Richards 3 22/09/15

Elsewhere:

https://www.practicalmachinist.com/vb/general/hepworth-hydraulic-copy-attachment-colchester-mascot-mastiff-276936/

https://www.practicalmachinist.com/vb/tooling-parts-and-accessories-for-sale-or-wanted/hepworth-tracer-parts-334957/

https://www.practicalmachinist.com/vb/general/help-hydraulic-tracer-238449/

YouTube

"Colchester lathe with tracer attachment" by biomorphical

"Trace it" by Keith Fenner

Interlibrary loan:

https://ieeexplore.ieee.org/author/37624173600