Myford Lever Action Tailstock Design and Build

PS, Noel, is this the type of lever tailstock you have, below? With the offset handle rather than the earlier straight handle? If so, one more question: What is the centre distance between the two pivot pin holes in the handle?

And is the handle shaft parallel to the line between those two pivot holes or is it angled back slightly? Cant tell from pics for sure.

I am thinking now that I might make this type of handle rather than the straight one in my earlier pics. Looks like the pivot bolts are closer together so more leverage given, and the long handle can be slid in out of the way or for less leverage on small jobs. There must be some reason they changed from the straight handle to this one??  Bit more of a fiddle to make, but I reckon I could fabricate it from two pieces of square bar welded together.

Edited By Hopper on 16/03/2022 01:41:17

The type in the picture above is the one I fitted to my ML7, I bought it secondhand and was never sure if it was a Myford made item or third party. Never seen another one that I can remember, I left the operating arm loose in it's bore ( I think there was a grub screw) and it could be slid in and out to vary the leverage and keep it out of the way.

Always found it a useful addition to the lathe, would make a good project for fabrication, following this thread with great interest.

Dave

Hi Hopper, Pivot pin holes are 1.625" apart. The pinch bolt is 1/4BSF. YES there is a small angle between the pivot bolts and the handle, I will measure when I get home protractor is at work !

Dave, Yes this is a genuine myford part. The made 2, I have the other one ! Myford did in fact use third parties to build a lot of their parts. If the one you have is as the picture then there should be a 1/4"BSF clamp bolt to lock the handle.

The one I have is new, bought with the longer S7 tailstock barrel missing, one day I will get round to making one !!!!!

Best wishes all, Noel.

Thanks Noel that's great, once again. That makes things clearer. I appreciate the effort.

Dave, thanks for your interest. Will keep up the posts if you are interested.

Here is the other type, presumably the earlier model, with the straight handle. It looks to me to have about twice the distance between the two pivot pins, which would give half as much leverage on the quill. Strange. But I believe this one too is a genuine Myford product as it is all over the net as such.

Compared with the later/Super 7 type Noel has

Will post an update on today's progress when I can upload pics. No wonder there are few in depth build threads on this forum. The pic process is painfully tedious, or tediously painful. Not sure which.

Edited By Hopper on 16/03/2022 10:09:11

Edited By Hopper on 16/03/2022 10:10:05

Blowing this pic up on screen until the overall handle length is 12" (roughly full size) , the distance between the two pivot bolts on the handle measures 3", so pretty close to double the 1.625" on Noels later type. Interesting. I might have to go for the harder to make later type and get more leverage for poking that 1" drill through 3/4" plate next time.

Noel, notice the different type of stop on this one. That's where the tapped hole in the quill clamp came from on mine. We'll see how it works in practice. Can always drill out and fit the larger 5/16 plain shank with pinch bolt later.

Edited By Hopper on 16/03/2022 10:22:14

Thanks Noel always wondered if that was a Myford part, interestingly the ones in the pictures show a replacement plain tailstock spindle, mine just clamped over the threaded part of the original ML7 tailstock quill. It was secondhand so maybe that just didn't come with it, worked fine with the standard ML7 quill.

Please keep up the post's Hopper, always interested in a build log, there's always something to learn and an " why didn't I think of that moment". Also interested if you build one for your Drummond, I had an M type years ago that i stupidly sold to buy a Cromwell S800, lovely lathe but couldn't get on with it, one day I'll get myself another M and rebuild it along with all the mod's and accessories that I've seen for them. Eeking out my redundancy money untill I get my pension this July, so no toys at the moment!

Dave

OK, so slow progress today, on several accounts. The termite exterminator man came this morning to do an inspection 12 months after he sprayed for termites that were eating away at my wooden shelving and storage boxes in the workshop. All clear. He is a North Queensland old timer so we spent about half an hour checking for termites and another hour chinwagging and solving the world's problems. He's a lovely bloke.

Then it started raining buckets so no chance of finishing off the quill clamp on the outdoor linishing belt.

I wish I could train those termites to eat metal along a straight line as I had some trouble doing the same on the 3/4" thick steel tailstock body clamp I carried on with. I tried milling the 1/4" slot in it for the 3/4" x 1/4" link to fit into. But either the 3/4" plate was too solid and the cutter too flimsy, under the less than rigid conditions of using the vertical slide on the ML7. Either that or I was too heavy handed with it. Possible, as the last milling machine I used was a big old Cincinnati that weighed 19,000 Lbs, and that was some years ago. But despite my best efforts taking a 1/8" deep cut across the 3/4" plate, just as it broke out the other side, the cutter started sparking and jumping around and growling like an unregistered dog. I backed off the hand feed but as soon as I tried again the cutter clean snapped in half.

The broken cutter shown here with the completed slot it did NOT cut:

So it was back to Plan A and I drilled a 15/32 hole where I wanted the end of the slot to be and made two careful cuts with the bandsaw, in horizontal mode with the job held in the vice. With a brand new blade in it to replace the Chinese original it cut straight as a die and I reckon I only had to file out way less than 10 thou to make it a nice fit on my piece of 1/4" flat bar for the link. Beautiful. Fits in there like a glove.

So now it is starting to look like I have something:

Which is always encouraging. And I will probably need it tomorrow with the task of bandsawing that 3/4" steel plate into a nice curvaceous looking facsimile of the original Myford casting. Tossing up between whether to wimp out and just make it all straight cuts done in the vice, or get fanatical and keep trimming it down into curves then finish it off with the angle grinder and linishing belt. A lot of work. We'll see what the morrow brings.

Edited By Hopper on 16/03/2022 11:04:52

Haha, I am familiar with that type of financial scenario. I dont know that I will make a second one for the Drummond M Type. Maybe buy the castings of the IO group when shipping to Australia returns to normal. I like the old Drummond. It is a more accurate lathe than my ML7. Very very good for small precision work. But the smaller spindle and bearing diameter make it more limited for bigger heavier jobs. The spindle has been chewed up where the pulley rotates in back gear so one day I will get around to making a larger diameter spindle out of 4140 and boring out the bearings to suit, as per Shrubsole or Jenkins or someone did in ME/MEW years ago. I have the article on file , just waiting for the day. Will machine the flat belt pulleys to take Poly-V belt at the same time.

Edited By Hopper on 16/03/2022 11:14:41

Hi Hopper The angle you suspected was there is 12* to the rear (away from the headstock). Hope this helps. I have sent a PM. Dave, the plain tailstock spindle is the new S7 type.  One thing that is seldom mentioned is the use of ROTABROACHES to make large holes, they go from 11mm to at least 50mm. Noel.

Edited By noel shelley on 16/03/2022 17:13:19

Thanks again Noel. I will have a sit down with the scrap box and see what can be fabricated to duplicate the handle casting part.

Yes I thought of rotabroaches several times while boring out that hole. But sadly I have none. My mate picked up a boxfull at the dump that someone had thrown out just before he arrived to dump an old lawnmower. I never seem to have that kind of luck! I reckon a 50mm job might put a bit of strain on that little key in the Myford tailstock keyway though.

A small but worthwhile feature of the Rotabroach or similar is that particularly when used without a pilot they produce a useful slug of material on completion of the cut.

I take the point about the strain on the keyway but, of course, size for size they produce less chips than drilling/boring; the chips, however, are long and curly. Incidentally, it seems possible that using them with the lever feed tailstock would allow the lever to react some of the torque.

Yes probably less torque than that 1" drill bit I used when you think about it. And you could always use the old time machinists dodge of putting a lathe drive dog around the drill or rotabroach shank with the tail bearing against the carriage to take the load off the tailstock key.

Ian Bradley (half of Duplex partnership) published full designs in Model Engineer back in the 1950s.

Thanks David. I'll look it up. I have Bradley's book "Lathe Devices" which includes drawings of a more upmarket model that allows you to keep the tailstock handwheel in place but I decided I prefer the standard Myford type. Not sure if the one in the book is the same as the ME article. And Geoff Walker did a remake of this one in MEW a couple of years ago and I have those drawings, but it is a different arrangement altogether frrom the stock Myford unit.

A quick check reveals the index shows a pair of Duplex articles on making a lever tailstock for Myford in 1952 in Volume 106, issues 2654 and 2656. The latter includes full drawings, it says. No mention of it being the one that retains the handwheel. So I shall see if I can track down copies of those issues,, or someone who can scan a copy for me.

Thanks for the tip.

I made good progress today on bandsawing the outline, despite battling several pieces of substandard Chinese machinery along the way. Will post some pics after dinner. Hungry work running that bandsaw.

Edited By Hopper on 17/03/2022 09:23:11

Hi Hopper

That brings it back I think.

I believe it does leave the original hand wheel intact. I think where the half plate holds them wheel in place there is a shaped piece that can pivot out of the way to release the hand wheel. Only applicable to the old style Myford tailstock with the large round back end.

I believe Duplex did other tailstock attachments including a powered one possibly for a Myford M series or maybe a Drummond. M Lathe. I can see it in my mind but not the make of lathe.

Hi Hopper

You could drill the outline and knock the waste off.

Then finish with a file.

Yes that's the way I have done it in the past but my days of cold chiselling and filing are well and truly over. Just can't do it anymore. So I have this fancy new Chinese bandsaw that takes all the manual labour out of it. I'm loving it.

Yes the Geoff Saunders remake of Duplex design has the removeable half plate on a pivot, that's the one.

Hi Hopper

I've sent you a PM.

Keith

Hopper:

I realise that you are reproducing the Myford item but may I commend a more comfortable style of handle?

Hi Hopper

I new I had seen other lever feeds in the past. I can usually remember most of the articles in ME over the years but not all the fine details.

For instance I remember a nice little drilling/ boring machine based on two bars like the original Unimat SL just by thinking about back issues.

it is al in my head, I just have to reindex it.

unfortunately I can no longer read the small text in the old MEs by I do have a lot of the early ones on PDF that I can read. Only just remembered I have got them.

That is why I like posting on the forum. As well as helping otes it helps me remember for myself.

No I am not senile, just old.

i knowwhat senile feels like. I thought I was losing my mind a while back. I was trying to remember lots of things and was completely confused. I eventually put it down to lack of food and weakness.

The trouble is I rarely feel hungry and am concentrating so much I forget to eat.