Member postings for Graham Meek

The last FB2 I owned was 26 years old, I had never changed this nut or adjusted the backlash setting. The weight of the head always meant the backlash was taken up.

It had always been my intention to replace this nut with a Phos Bronze one, but I never did get around to it.

Having checked the Emco Holz & Hobby site they do not list this nut as a spare anymore, so the home manufacture of a new one would be a priority in my book.

If anyone has access to a nut perhaps they could supply a drawing to help other users, should they find themselves in this predicament.

Regards

Gray,

Pore size is dependant upon the applied voltage. In my experience I have never known it affect the colouring or dyeing of the anodised surface afterwards.

Regards

Gray,

Many of the spares and accessories are still available new at Emco Holz & Hobby in Germany. Prices I have found are cheaper than second hand off Ebay. Delivery is about 1 week on average, but depending on where you live in the world, carriage may be a problem.

Allen capscrews for holding the chuck are M5 and come in various lengths, 20 mm long for the Faceplate, 25 mm for the 4 Jaw chuck and 30 mm for the Original 3 Jaw chuck. The Collet chuck lists 10 mm long M5 Hexagon headed bolts

Regards

Gray,

Hi Neville,

I have sent you a PM, you may be able to help me.

Regards

Gray,

Hi Julius,

Further to your PM, I have sent you a reply.

Regards

Gray,

This was my final set-up using my much modified Non-Picador grinding jig. A White recessed wheel from Axminster and a diamond, set-up so as to sweep the entire face. There is a micrometer adjustment on the diamond. This method also produces the grinding marks on the drill lip for maximum cutting edge longevity. (Grinding marks should be at 90 degrees to the cutting edge for maximum cutting edge life).

Regards

Gray

Emco used to produce a Handbook for Students and Teachers. It was called "Basic Technical Information and Practical Applications of the Unimat 3, Universal Miniature Machine Tool"

Although the Unimat 3 is smaller than the Compact 5 (C5). The C5 shares many of the design features of the Unimat as well as the across the bed dimensions.

This book covers a lot of things simply. From how to use / read a Micrometer & Vernier. Through drawing techniques and projections, to how materials are made and the various cutting angles to machine them. As well as an explanation of the various elements of the lathe and milling machine.

It is in my opinion a good starting point and many of my apprentices over the years have found it useful.

Regards

Gray

As the FB2 is going shortly I thought I would share one last photograph with those who have been following the post.

I have given the Delrin Gear assembly an extended trial since my last post. It has had a solid 6 months machining a wide variety of materials, with different metal removal rates. The gear shows no sign of distress and if anything it was a lot quieter in use.

I hope all those who have followed this post have found it interesting and helpful.

Regards

Gray,

Despite the workshop being in mess due to the larger machines going. I have had a chance to make the new Topslide Feed screw and the Main Body for the Retracting Topslide.

This was machined on the C5 from a long old 10 mm bolt. I find this material machines well and screw cutting is a pleasure. As was using the Screw cutting clutch on the C5. Of course it would have been quicker with the retracting topslide.

The Main Body was machined on the new Proxxon Mill and after locating all the holes by co-ordinates the bores were finished on the C5 using the 4 Jaw chuck.

Regards

Gray,

I am deeply saddened to hear about the loss of such a kind and helpful man. He was instrumental in getting me to put pen to paper and bring to the Hobby my designs. He also took me by surprise when he said he wanted to put my articles into a book, but he obviously knew his business.

I shall miss being able to catch up with him at the exhibitions.

Our thoughts are with his family at this difficult time.

Jean & Gray,

I have had a 12v Proxxon for over 10 years, it has done a lot of work and is still fine, never gets hot and is above all quiet compared to some I have used.

Regards

Gray,

Work has ground to a halt on these projects for a short while. I need to spend time getting the larger machines out of the workshop.

As a taste of what is coming I have enclosed one of John Slater's 3D views of the Retracting Topslide attachment.

Since John has made this drawing I have moved the Operating handle to the other side of the unit. That way it does not foul the Tailstock.

Regards

Gray,

Dear Jouke,

The leadscrew engagement on the Handwheel conversion is carried out by the lever on the left-hand side of the carriage. This lifts a cylindrical half nut via an eccentric into engagement with the leadscrew. The cylindrical half nut is keyed to stop it rotating so alignment with the leadscrew is always assured. (One half nut has been used on numerous occasions in the past by various lathe manufacturers).

While your C5 powered cross feed sounds an elegant design. I think if I were trying to do this I would start with a C5 CNC cross slide and carriage assembly. These regularly come up on the Internet for sale. I think this would be an easier starting point. A plus point is these parts are, I believe, made from Cast Iron.

With regards to my design modifications. I pride myself in that I do not modify the existing machines in any way. I always make use of existing tapped holes for attachment points. No existing Emco part was modified in this recent design and my C5 could be put back to standard in a matter of minutes.

Regards

Gray,

Dear Jouke,

Stops on the trip rod running along the front of the machine can be set to any desired thread length, with-in the limitations of the machine. The trip rod moves to the left or right depending on the operating lever position. Which dictates whether the the thread is a RH or LH. Moving the operating lever to the right means the trip rod moves to the left and visa versa.

The operating lever works the banana shaped plate, at one end of this is the trip rod and at the other is the dog clutch selector. Thus any movement of the trip rod directly affects the dog clutch selector.

As the carriage moves along the bed during screwcutting it makes contact with the stop, 2.5 mm later the dog clutch is disengaged. Moving the operating lever in the opposite direction, after withdrawing the tool, returns the carriage to the start position.

As there is only one tooth on the dog clutch it can only pick up the drive at one pitch intervals.

Regarding the hand wheel position, this end was chosen so as to utilise the existing leadscrew nut fixing position and to retain the original operating force position on the carriage.

In my experience there is always a dead space at the headstock end of the bed due to the chucks, faceplate and catch plate attached to the mandrel. I therefore did not consider there would be much loss of travel. However in this instance I may be wrong.

I hope these notes help,

Regards

Gray,

PS

I have just completed a new topslide feedscrew using the above attachment, I hope to post a photograph soon. Which is for the next phase of the mods, a Retracting Topslide.

One thing I did forget to mention is that the gears were made using the Emco Compact 5 Dividing attachment and are all 1 MOD.

Regards

Gray,

Hi Kiwi Bloke,

Thanks for your kind comments, there were times when I nearly abandoned the whole idea. Thankfully things are now on the up and life goes on.

I'd like to take the opportunity to mention that I don't think a lot of people realise the cross-section of the C5 Bed ways are identical to the Unimat 3/4. I recently posted on here, about the restoration of a Unimat 3 that was given to me. It was a bit of a basket case and was fitted with a large induction motor all suspended off the headstock.

Despite the obvious abuse to this machine in it's life, there was zero wear on the bed ways. The Tailstock and Cross-slide assembly were worn but the wear was nothing like I was expecting.

Fortunately Emco saw the light with my C5 as this one comes with an adjustable / replaceable cross feed nut. The Leadscrew nut also benefits from a backlash adjustable feed nut. The trip-rod bracket is anchored off this adjustment screw.

Thus I think given my intended use for these two machines I don't see wear being a problem.

I did draw-out such an apron attachment some while ago, but as yet I have not got around to making it.

Whether I ever will, is another story, I might if I get the chance to obtain another C5.

Regards

Gray,

Hi Joe,

As mentioned above things are on the mend now, so I am doing OK thanks. The C5 project has been a God send really, if a lot of very hard work given the timescale I set myself.

Unfortunately the FB2 is going as well. While it will be hard to see both of them go, it has to be done sometime. Better to do it while I am able to. The machines will make someone else happy and I hope they get as much enjoyment out of them as I have had. I am really looking forward to using the smaller machines, I started out with a Unimat SL 64 years ago.

As regards the CNC, sorry appearances can often deceive. Everything was done by first principles and the trusty Emco Rotary table. Total machining time was just over two days.

Regards

Gray,

After deciding to downsize my workshop in January, the need to get the Compact 5 (C5) up to a standard I was comfortable with became a priority. The use of my larger machines would be of benefit while they were still here.

Having had the luxury of the Screwcutting Clutch on the Maximat Super 11 it was something I was not happy to do without. The C5 had always been tempting me to do this mod, so during my recuperation in February I set about designing the attachment.

The above view shows the Mk1, and it also shows you really need to be in the workshop more. The reason being I had forgotten to allow for the dis-engagement of the Leadscrew. This being a necessary requirement on the C5, other wise in Manual mode the operator has to turn the banjo gears as well.

This need to retain the C5 disengagement Knob meant the Operating lever would need to move from the chosen site where the knob was to in front of the headstock. Thankfully during the need to do a complete redesign of the main body it was possible to have both controls in the one place.

The keen eyed amongst you will notice the main body is now in two halves, or parts. Again had I have been a more frequent visitor to my workshop at the time, I would have noticed the Bracket welded to the inside of the Headstock cover, which takes the cover locking screw.

Had it been possible to retract the leadscrew with drive key attached through the bearing in the lathe bed, then the original design would still have worked. Unfortunately the key stands proud of the shaft and this cannot happen. Thus there was nothing to do but start again with two halves, and yes this was after I had machined the main body in one. Of course I could have cut the bracket off, but that is not how Graham operates.

The redesign also threw up another problem, in that the Dog Clutch, because of the split line needed to sit higher in the upper part of the main body. Unfortunately this brought the dog clutch selector into conflict with the drive belts when changing to the lowest Mandrel speed. This was eventually overcome by machining a flat on the selector similar to the flank on a camshaft. An eccentric balance weight is yet to be made and fitted to the outer end of the selector shaft.

A new bearing assembly was also made for the Leadscrew handwheel which has some Radial ball bearings in. The housing was extended towards the Headstock to provide the anchor point for the outer Trip Rod support. The ball bearings will eliminate wear to the leadscrew end face and give better repeatability when screwcutting.

While I have used this lathe for screwcutting in the past, it was a rather hair raising experience. This attachment now completely eliminates the heart stopping moment as the tool approaches the chuck jaws.

I will in due course go on to describe other attachments for the C5, two of which get the benefit of the screwcutting clutch. I hope you have enjoyed my rather long winded post.

Regards

Gray,

Edited By Graham Meek on 15/05/2022 11:20:55

Edited By JasonB on 30/06/2022 20:35:31

Hi Jamie,

That is a lovely piece of work, you should be justly proud of that.

Using an H7 reamer will give you the same size hole as the Oilite bush. These are normally supplied to give an H7 bore when they are pressed into a hole which is itself H7.

Hopper has the best option and it is something I have done in the past. That being to machine a custom Oilite bush. Billets of solid Oilite used to be available and this would give a better self lubricating bearing solution.

Torlon in my experience takes on moisture so you might have problems with this material. Especially if it is machined in a humid atmosphere and then lives in a relatively dry environment.

Regards

Gray,

When I recently made a new spindle for my Proxxon milling machine, (posted elsewhere on the Forum). Knowing whether any run-out I was getting at the spindle was due to the Collet, or my workmanship, was a primary requirement. I checked the collets before hand in the following manner.

A ground dowel of nominal collet diameter was gripped in the lathe collet chuck. The dowel was checked to see if it was parallel to the lathe centre-line, in the vertical plane. The subject collet was then placed over the dowel and abutted against the collet holding the dowel.

A DTI was then set to indicate on the cone diameter and the collet rotated by hand whilst gently urging it against the "holding Collet". The collets I had obtained from Arc showed no signs of error with my 0.002mm division clock.

Admittedly this does assume the two end faces in contact are perfectly square. However if this is this problem it will show by a progressively low spot reading. At both locations of the clock on the cone diameter. Turning the collet end for end on the dowel should eliminate this sort of error. If it persists then I would say the error is run-out

When I installed the new spindle and checked with one of my collets. Using the same dowel, and DTI, TIR was less than one division on the clock. Which for milling is good enough for me.

Regards

Gray,

Greetings from the other side of the County, (Forest of Dean),

Always plenty of advice to be had here, whenever you need it.

Good luck with the lathe purchase.

Regards

Gray,