Member postings for DMR

1/4" BSF. Only the outer 0.350" or so is threaded. The rest measures 0.193" dia or 4.9mm (just a BSF clearance) and is about 0.750" long with a bit of a lead-in taper at the inner end. Overall length is about 1.080". I have a used spare in my hand but new Myford will sell you one. Part A1987 Backgear eccentric screw. Same on Mk1 as the later ones up to metrication.

Good luck, Dennis

Dave,

I am entering this conversation without reading it all so just three points:-

1) The yellow down the middle of the bed depicted an unhardened bed. A hardened bed was painted red.

2) A wide gauge saddle will not work on your early bed. The leadscrew claspnut will not line-up.

3) The Brass tube on the drip-feed is a push fit, straight sided arrangement. You need a good BSF bolt (1/4 BSF I think) that will screw in the length of the thread so as to have a fair chance of not stripping it. Set up a lever arrangement to the back side of the oil well and pull straight up; it gives way very suddenly - frightening!

As to your cracked white back piece. Once you have it out, assuming it has not been bodge-glued in before, apply some Araldite or similar to the cleaned-up outside of the crack and that will do the job. I just run a bit of oil via the tap at start of session and that works fine. The sightglass was never meant to be filled, so no need for an oil-tight fit.

Dennis

Paul, The machine number starts SK?????. I can just make it out on the front of the bed in your pictures and it helps to quote it. The gearbox has a number too QC?????, stamped on the r/h end. You don't show any other chucks, particularly a 4 jaw (not drill chucks) Various aspects put it at early 60s and it has raising blocks, Myford stand, drip tray and of course gearbox. The motor on the floor seems extra - a spare in addition. There are no other extras like vertical slides, steadies, etc which would increase the value. Don't run it without checking oil levels and do you have the service manual? A buyer should want to see it run.

I don't think its been repainted: the finish is too good. Just never been used as in no paint chips and only basic additional equipment. Hence the superficial rust on unpainted surfaces. The state of the bed matters a lot and whether the carriage will slide all along it without any looseness. Include a picture of the l/h end of the bed for any damage as that means a lot too.

It would help you to say where your are in your profile, if only approximately, and a buyer may emerge locally. The world is as Tony and Dave say. If it is the unused/unworn machine it appears to me to be then 2K is not impossible.

Dennis

Michael, I have sent you a PM with my e-mail address.

Dennis

Michael,

The last S7 to have the "early" expanding clutch was SK 8127 made in June 1958 so your 1964 (It is) bed has been married to an early clutch at some time in the past.

I no longer have an early clutch but the shaft end float you describe should not exist. Do you have the red fibre thrust washers (2 off towards each shaft end) shown as item 4 in Robbo's part diagram? They were about 1mm thick each and would account for the float. As to the drag, the clutch ring should be free inside the pulley in its relaxed state while you have it apart, and it sounds like you were trying to remove the adjusting screw with the clutch engaged which is wrong. The adjusting screw should be domed where it meets the taper slot in the Actuating Bar. I have the early manual pages for setting the clutch which I can e-mail if you want them.

Dennis

Robbo beat me with some of this

Edited By DMR on 19/05/2018 01:20:13

Edited By DMR on 19/05/2018 01:22:31

So it is a Verdict.

Your "hair spring' in your top picture is bent such that it appears to be trying to move the main lever upwards but the lever has not moved upwards. Couple that with the external ball-end knob in your bottom picture being apparently centre biased then the spring should be quite straight and unseen under the main lever, unless things have changed between pictures.

Edited By DMR on 02/05/2018 22:52:48

Martin,

To me, your verdict is not just elderly, it's very elderly/old and nothing like the pictures posted. Does it say Verdict on the dial or are you just referring to it as a Verdict type? Go back to my first post and consider that the dial pointer only travels just over one full turn. Move the lever under the dial to each extreme and you should find that the dial pointer reverses its action by one turn. The probe then works the dial in the other direction. It is not a centre-zero device. Rotate the dial's bezel to reset to read zero if required. If you do have a fault the spring wire (your "hair spring" description I think) on the inside end of the external lever looks bent in your top picture.

Mick,

I have no idea how old my Verdicts are; they came to me with a Myford years ago. I would assume that a plastic lever would represent a more recent 'improvement' as they say. I have three of them, all in their blue boxes with fittings but I only ever use one of them and there are multiple variations of the included fittings The two unused ones have one inch diam dials and 0.01mm and 0.001" ranges. The inches one sports an extended probe (by me) to the original, 20mm long instead of the original 10mm that I made when I needed longer reach, not considering the loss of sensitivity as a result. Just a means to a tricky end. Incidentally I have two spanners to fit the flats on the probes included in the boxes so some gauges probably came with multiple probes with different lengths and/or tips.

The DTI I do use has a 1.5" dial and 0.0005" scale which totally beats the other two, I normally use a dial gauge through choice and never measure with any of them.

Dennis

Just for Martin's sake (and if we have diagnosed his problem correctly) I have put some pictures in an album of what the lever under the dial should look like. The washer is chamfered on the outside and creates friction with the lever to hold the lever in place. Have a go Martin. Don't sling it.

Dennis

You seem to be misunderstanding the action that is supposed to happen. Non Verdict DTI's sit (sort of) in mid range and will work either way, not necessarily returning to a zero on the dial unless you rotate the bezel to read zero. Some of mine go a bit over a full turn each way but one does one and a half turns each way.

Your Verdict should have a little external knob under the dial which biases the action one way or the other. It is not meant to go plus-minus of some reading and the full needle rotation is only just over one turn. That is to say that the needle is biased to one end, or the other, of its one turn by the external lever under the dial. On some the little lever was plastic and broke off but you can replace it with a bit of sheet springy steel correctly bent. I seem to recall I repaired one once. If you have a missing lever and nothing to go on to make a suitable replacement (another Verdict) then you will struggle. It has a washer and a pin externally too. The shaft for the lever should exist with its cross hole for the pin.
Hope that makes sense. Could try and take some pictures for you, but it's all tiny. PM me if you wish.

Dennis

Hi Piero,

Well you have a later Myford Metric Conversion Set there. The label clearly states part number 1481/1 but also mysteriously states "For QC2495 and onwards". "QC" stands for Quick Change. I have always understood that gearboxes from QC2501 were the later pattern.

Anyway, you have the later gears set which is not ideal for your gearbox. I think you may have counted teeth wrongly, for instance the one cog in the layer with the change gear quadrant (or banjo) I believe is 30t. and you list 2x28t and no 30t at all. There is only one 28t in the set and unlikely to be use for 2. However, my set only consists of 12 gears and your set has 14 but, as I said before, some gears may have been added and there is evidence of different paint colours!

To cut metric threads with some accuracy you replace the fixed gear set inside the changewheel cover with the quadrant in the box. The circular hole in the quadrant fits over the gearbox input shaft. The two shafts in the layer with the quadrant need fitting first (remove the nut, sleeve and washer first) as they go into the back of it. All is clear if you have the pictorial of the quadrant that I stated in my previous post of 28 Nov.

Do you actually have the 12 gears that I listed in that post? If so, how many teeth do the other two gears have? Another complication to answering your problems is that my Metric Set is on three layers in its (original) box, but the layer with the quadrant is the same as yours. Do all 4 layers fit inside the original Myford box or do only 3 layers fit? We could talk about this better if you PM me your e-mail and I can supply tables of cog set-ups which will work for your gearbox. But you do need a few extra gears to be able to cut all threads.

Lastly, your opening question and pictures included a washer with a keyway cutout. There should be two of those included in the set, 50thou thick. The shaft in those pictures may be the same as the 2 shafts in the layer with the quadrant piece, and if so is a spare. The 30t in the pictures is not Myford if it is, as you stated 1/2" thick. Do not be tempted to try and use it with the metric set.

Dennis

Hi Piero,

1) No new photo's on this site. Have you put them in Photobucket or something else?

2) Your stated list of gears is not a Myford one I recognise. You have listed 45t twice separately, is that an error? Your list does not fit the non-gearbox selection either.

3) A picture of the banjo may reveal what the set belongs to. Is there a label one the box? Is there a number on the box?

4) You stated at the start that the 30t was 1/2" wide. Are they all 1/2" wide? Myfords are 3/8" wide.. Do they have a keyway cut? Are there any holes in the gears near the middle besides the centre hole?

5) Have you obtained a replacement leadscrew and fitted it?

6) Have you rebuilt the gearbox and had it working?

Is there anyone near this chap in St Albans willing to help him out?

Regards

Dennis

Hi Piero,

The early "Metric Conversion Set" for the gearbox you have consisted of 10 gears as follows: 20T, 30T, 35T, 40T, 44T, 45T, 52T, 55T & 2x60T. If you have these in your box then you have the early set. The pictorial supplied by Simon and which you have on your changewheel door is the correct one for your lathe, but the conversion set that you have may be a later set for the newer gearbox. As further clarification the only difference between the two sets is in the gear selections, all the other parts stayed the same.

The later set consists of 12 gears: 28T, 30T, 35T, 40T, 2x45T, 2x50T, 55T, 2x60T, 63T. With my set of later gears in its box, I have supplemented the set with additional cogs and any previous owner may have done the same or similar with the set you now have. My choice of my extra 6 cogs gives me all the options for any thread using the early gearbox.

The use of the metric quadrant is fully explained in the gearbox manual, most likely page 6, along with a pictorial of all the parts you should have in the box. The parts list also shows the Conversion set pictorial and if that fails the Myford site has it for free under gearbox. The washer and shaft in your pictures should be in the box and probably the two cogs as well if there are spaces in the cardboard cutouts for them to fit. There is nowhere in the box for the tumbler sleeve gear. Note that as already explained, the ratios in the later gearbox manual do not work on your gearbox.

As an additional note, The early "Metric Set" on the early gearbox did not give as accurate threads as the later combinations.

Hope that helps

Dennis

Oops,

Quite right Simon, Old age strikes again. I only formulated my own "metric roughs' tables for my newer machine. I must get round to doing the same table for my older one. Divide by 2 with quirks. I prefer my threads to be right, so I've never actually used the option.

Dennis

repeat post

Edited By DMR on 27/11/2017 16:21:40

Hi Piero,

You have identified the tumbler stud sleeve gear 10351. This replaces the 12 tooth ganged tumbler stud that is fitted on your machine as you seem to have worked out. On a more modern machine your 12T would be a 24T and the 10351 part would be a standard part. Your gearbox needs the 12T you have to operate correctly. Its a left over from the ML7 days. The washer in your picture will be 50 thou thick and along with the shaft piece are part of the metric conversion kit, which must have existed with your lathe at one time along with a set of gears which DO NOT form part of the current metric conversion set as the external gearing on your early gearbox is different.

You have previously said that you want to work in imperial, not metric. You can cut short metric and BA thread approximations with what you have by fitting the 10351 plus 20T, 21T, 33T or 34T (mostly the 33 & 34) onto the 10351 part. If you want to cut more accurate metric threads, then you need the metric conversion set, but you would have to supplement the supplied cogs in that set to cut all metric threads on your early gearbox.

Various mails on here talk about rough Myford metric screwcutting using the gearbox. I have deleted our previous correspondence and repeat my e-mail in a PM if all is not clear now.

Dennis

Edited By DMR on 27/11/2017 16:23:23

Edited By DMR on 27/11/2017 16:24:19

Hi Ronald, The Algoa gearbox is nothing like the Myford one internally or externally and is kit built as you have found. You will need someone who has built the Algoa version to help you unless Neil and Chris have already landed on the answer. I did type into Google "algoa+gearbox" and came up with the following great long link (copy/pasted so it is right). About 2/3rds down is a fair bit on the device.

https://books.google.co.uk/books?id=gZLuDQAAQBAJ&pg=PA9-IA3&lpg=PA9-IA3&dq=algoa%2Bgearbox&source=bl&ots=iwHODqB6oZ&sig=OQa_A8qdLpdCmblSphcvVscZ58s&hl=en&sa=X&ved=0ahUKEwjK56D3z6jXAhVGIMAKHSFCDtUQ6AEIOjAD#v=onepage&q=algoa%2Bgearbox&f=false

Hope that helps

Dennis

As your equipment is old, you may find any degreaser degrades the material used in the manufacture. That aside, If your assembly looks oily or dirty stick to your plan A, and the Halfords one is as good as any. However if it looks essentially clean, then read on.

I guess you want to maintain the originality of the machine, and not fit a modern switch. You presumably mean that when you press the start button and release it the machine stops, or tends to sometimes . It seems you can view the contacts involved as you are going to squirt something at them, so.........If you examine the contact points in detail You may see that one has a spike on it, caused by arcing over many on/off actions. In that case, plan A will do nothing. There may be several contact pairs if the machine was ever 3 phase, so examine them all. Carefully remove any such spike, which may be quite hard. Don't remove more than you have to and leave a smooth/polished and clean contact. Don't bother about the hole in the other contact but clean it up if it looks dirty/sooty. Put all back together and try it again.

As already stated, ensure you are working on dead equipment whatever you do. If you do use a degreaser, then don't use more than is necessary and let any solvent evaporate totally before you reapply power. Hope that helps.

Dennis

OK John. That's a different angle. Thanks for that.

Dennis

I have to come back to this for a bit of clarification, and apply a corrected circuit diagram while I’m at it. I have now done the sums and moved towards the copper wire ordering stage.
The existing aluminium windings are as follows:
Main (run) winding 12.0 ohms. Approx 180 metres. Approx 22SWG.
Start winding 6.6 ohms. Approx 73 metres. Approx 24 SWG.
Equivalent copper windings will come out at around M = 7.75 ohms, S = 3.14 ohms.
That is significantly less and I fail to see how such a difference will make the motor run cooler. I fully realise that the related resultant inductance makes a lot of difference but the starting current is obviously going to be higher.
Would it not be sensible to go down an SWG (yes, I know that’s a bigger number) or even two to put the straight winding resistance back up? The smaller wire/s would be a free fit in the stator segments, but I could add more windings or use a (heat proof) filler. I favour going down one SWG and add more windings to fill the space or just use a smaller start winding wire, and using more turns. Has anyone in the know got any advise on that?
The enamel on the existing windings is hard to remove, possible due to overheating. Anyway I use the term “approx” for the SWG as the aluminium is soft and it is difficult to say if the wire involved, once scrapped, is to AWG, SWG, or just something the maker had to hand!

There is another point here. I discovered that the likes of RS, Farnell, etc only stock the AWG spec now, and not in a good (enough) range of lengths either. Wires.co.uk seems like a good bet.
Don’t blind me with science please. Just convince me on the right way to go; I'm not going down this path twice.

Thanks in anticipation.

Dennis

Edited By DMR on 25/08/2017 16:15:25

It has to be absolute bare steel. Did you leave the original Myford black where it still existed? Did you get any rust off? Iv'e never used Blackgates, but did you thin the blacking too much if it specified it? Even your inside surface looks patchy so I have to suspect your cleaning. Never handle it directly at all during or after cleaning it up; use two bits of wire in opposite holes and dunk it with them. The blacking needs to be in one go, over the whole surface, and there is no harm in leaving it in the oil at the end for longer. Hope that gives some clues.

Dennis

Edited By DMR on 18/08/2017 02:17:32