Member postings for Graham Meek

Hello Mark,

The two photographs below shows what happens when the drill angle is altered. In the first at 59 degrees the pivot centreline goes through the point at the end of the vee guide. This is represented by the pointer or scriber. It is from this point that the drill extension is measured to ensure the correct drill grinding geometry. The second photo shows what happens when the angle is altered to 45 degrees, the pointer has not moved.

There is a compromise with the original jigs as pointed out in my original article. If they are going to grind a myriad of angles then they are never going to grind one correctly without a certain amount of luck.

To get the jig to grind at 45 degrees reliably then it will either mean going through the whole sequence of evaluation which I went through,again, or play with the original jig at or near maximum eccentricity. Unless there is a requirement for a large number of drills ground to these angles, then it is far easier to compromise.

The original project I had in mind was to get this simple jig to work reliably each time at 59 degrees by following 4 simple steps. In using this jig it would be as quick as grinding by hand, but give a reliable result equal to a new drill

The eccentricity or offset is diameter dependant. The larger the drill diameter, the larger the offset, D/13 is the ratio required.

Regards

Gray,

Hello Keith,

I must apologise for not replying to your post sooner. The truth is I have only just read this as I was about to post the following photograph.

It had been my intention to write up a series on the lathe adjustments and alignments, a start on the articles was made. At that time Tee Publishing owned EiM but unfortunately due to changes of ownership and other things in the interim this fell by the wayside. As I no longer write for this mag I doubt it will ever get published.

Regards

Gray,

I have just completed a new arrangement of my drill grinding set-up. I thought it might interest the forum. The drills are now ground as they would when leaving the factory as regards the grinding wheel marks being perpendicular to the cutting edge. This promotes the cutting edge life, grinding lines running parallel to the cutting edge weaken it considerably.

The steel plate under the jig is set perpendicular to the grinding wheel face. The grinder has its own built in wheel dresser. Which due to its inclination gives a micro adjustment facility. A guard is going to be fitted to the exposed cup wheel periphery. A boss is provided at the rear of the dresser mount which will allow it to pivot out of the way when drill grinding but cover the wheel when using the wet grinder. The rest of which is also my design.

Regards

Gray,

Just thought I would update the forum on the progress of the Prototypes. I have been lucky in that John Slater has produced some lovely 3D images of the Dial conversion. I could not have done this project without his help, KWIL's, and that of Michael M who initially asked if I had done anything about the S7 Tailstock Dial. Which in turn started me thinking about the problem and this attachment.

I have also been told from several sources that the difference between the tailstock Mk's is all down to the position of the Barrel Locking Lever. Horizontal means it is a MK1 and vertical being a MK2.

Regards

Gray,

Hi Sam,

The Quill assembly is all new. It is 8 mm longer than the standard Quill in order to accommodate the front taper roller bearing. The keyway slot shown would break into the bore of the new bearing on a standard Quill. The top bearing is an angular contact bearing.

The Sleeve was made from EN 8 and the new spindle was machined and ground from EN24T. The whole purpose of this new quill was to try a new bearing arrangement. At the same time I was making a new standard Quill sleeve with a larger outside diameter, for a better fit in the milling head bore.

Was this new set-up any better than the standard set-up? That is hard to say, I could not see any visible difference. There was no improvement in milled surfaces. If anything the standard needle roller bearing will withstand more load than the taper roller bearing, according to the bearing catalogue.

Regards

Gray,

Posted by Kiwi Bloke 1 on 26/09/2018 08:41:11:

I'm sure I remember seeing something in this forum about the conversion of the needle roller bearing (& the others, of course) to taper roller bearings. Now I can't find it. Perhaps I'm mistaken. However, I think Graham Meek may have been involved. His earlier posts seem to have been redacted from various threads, which is most unfortunate for his followers. It's good to see his return to the forum. Perhaps he'll notice this thread and enlighten us.

You were right, guilty as charged. Please find below the missing images

Gray,

There appears to be two types of Tailstock fitted to the Super 7. A Mk 1 and Mk 2, can anyone shed some light on the differences between these Mk's? I would hate to restrict the design to fit only one type.

Regards

Gray,

Sam,

I have sent you a PM

Gray,

Hello Brian,

I am sorry I omitted to say that the Dial will be able to be set to Zero at any point. The friction device has been proven over many years on my Myford series 7 Handwheel Dial design for the Carriage, or Apron handwheel. This is incorporated with the sleeve gear that rotates on the Tailstock Handwheel boss. The Handwheel boss needs to be machined by the way to 24 mm diameter. This is somewhat smaller than in the George Thomas design, hence why I used the needle roller thrust race.

Regards

Gray,

Michael and Mike,

Thanks for the compliments

As regards publication, I am a long way off from that at the moment. I never write about anything unless I have made the item myself and currently I am wading through the parts drawings. Plus I could do to source a donor Tailstock from somewhere to help with the photographs, it will all take time.

Regards

Gray,

I was recently approached by a member of the Forum as regards had I done anything with the Tailstock dial on the Super 7. My initial answer was no, and that I did not foresee any prospect of doing such in the future. Not owning a Super 7 now would make the task harder.

George Thomas did an elegant solution to this problem some years back. A Tailstock Micrometer, chapter 14, page 160 of the first edition, "The Model Engineers Workshop Manual". While 0.300" per rev is fine for the Imperial user, although a little awkward as regards the tailstock barrel graduations, 1/8 th's. It was not so good when it came to a lathe with Metric units.

As is usual when a seed has been sown, an idea germinates. The initial problem with involving gearing in this dial is the need to keep the Dial small so as not to obstruct the handwheel in use. Normal reduction gearing would lead to an extra large dial.

The Eureka moment came when I was thinking about another problem. Speeding up the initial gear train then reducing it leads to a more compact Dial. Due to the reduction in bearing area on the face of the handwheel boss a needle roller thrust race has been added to make ejecting centres, arbors, etc easier. This is a worthwhile mod without the dial. An oilite bush has also been added to reduce the need to lubricate the bearing after assembly. An annual top-up should be more than adequate.

The metric dial is graduated 0-10 mm per revolution but has an inbuilt error of reading plus on the 10 mm dimension by 0.000127 mm. Over the entire barrel travel this would be nothing to worry about. The imperial version is graduated 0-0.500" and has no error, that is always assuming a theoretical pitch of 0.300" to start with.

Plans are however in hand to produce an article on these dials. Whether one of the ME suppliers takes up the manufacture of these dials then it is early days. For my part I want no part in this side of things.

Regards

Gray,

Sam,

Provided it is an FB2 and not the earlier Mentor Mill, then spares for this machine should be available through Emco Stockists. Emco have a policy of keeping spares for their machines for 30 years. As I purchased one of the last FB2's in 1996, there should be about 8 years left.

If you do not know the spare part numbers, there are PDF's available on the manual, or Sears in the USA have, or did have an on-line parts catalogue for Emco machines.

Gray,

Hello Dave,

Thank you for your post.

I apologise in advance for side tracking this thread. As regards the Boxford Dog Clutch, a design was started but the person supplying me with the dimensions suddenly dropped out. No work on this design has been done since 2011. I enclose a photo of the scheme, but I doubt I shall ever finish it.

Gray,

At post number 6 above I wrote,

"The previous link on the second post was an article which was a precursor to a more detailed follow-up article. This appeared in EiM not long after my original post on this Forum, "Perfectly Ground Twist Drills every time". This article contained all the necessary drawings. As regards which issue/month that was I cannot say without wading through my back numbers. I am sure the more meticulous on this Forum have the answer to that."

Gray,

Dear all,

I had asked Neil to supply a short note to confirm that the Picador unit does not need to be modified. It works on a completely different principle to the "Clones". A friend has recently purchased a Picador complete with box and instructions. It worked flawlessly straight out of the box.

The original "Spiralux" unit introduced the leaning pivot pin. It also featured a different base which did not need the wedge shaped piece that I added. I think it would however benefit from the revised pivot pin arrangement. A picture of this design can bee seen on the following link, but you will have to "log-in"

www.modelenginemaker.com/index.php/topic,3788.30.html

The previous link on the second post was an article which was a precursor to a more detailed follow-up article. This appeared in EiM not long after my original post on this Forum, "Perfectly Ground Twist Drills every time". This article contained all the necessary drawings. As regards which issue/month that was I cannot say without wading through my back numbers. I am sure the more meticulous on this Forum have the answer to that.

I hope this clarifies things.

Gray