Member postings for Kiwi Bloke

Yep, you've got it. I'd imagine that the screw is there to limit the arc of movement of the lever to something that looks and feels 'right' rather than to limit the movement of the dog clutch per se.

Interesting to know that it's an M1. So that makes three types of saddle and two types of power feed mechanisms - at least. Yours must be a very late model. With these old machines, one sometimes wonders whether two were ever made the same...

To avoid confusion, ML7 bearings are parallel. It was only when the ML7R came along that a tapered bush was used. However, it's worth slackening off the thrust (end float) adjustment just to remove one possible cause of binding...

The 'torpedo pin' is the table knock-off plunger which, when pushed down by the (adjustable) knock-off dog on the front face of the table, throws the table auto-feed out of engagement, by turning the black-knobbed lever. Sorry, can't remember what the screw does.

Most of the M1 saddles I've seen have had the table feed lever supported by a cast-in boss on the saddle, not by, as yours seems to have, a bolted-on plate. The knob's shaft also sits near the bottom of the saddle, whereas yours seems to sit nearer the top (perhaps perspective distortion by the camera?). A late variant has the table dog bear directly on a pin sticking backwards from the hand lever, which is of flat section, and supported by a bolt-on plate.

Because of these differences, I think that your machine is actually a 'Junior' - just a little smaller than the M1.  Am I horribly mistaken (it has been known - according to my wife...)?

Edited By Kiwi Bloke on 11/01/2020 23:27:09

Edited By Kiwi Bloke on 11/01/2020 23:30:44

If your measurements are correct, there seems to be a misalignment or, more probably, an out-of-roundness of the bearing shells. Time to get out the 'blue' and check everything, and scrape the bearings. Plenty of instruction on the 'net (and in books...) about scraping. Some of it can be believed...

Chromebooks are a highly cost-effective way of getting reasonable hardware in a small package with a long battery life between charges. And there's no buried Micros**t licence fee to pay... However, the limited on-board storage may initially be seen as a limitation. Therefore, it's probably a good idea not to clog up the ssd with multiple operating systems. ChromeOS is designed for an on-line existence and is too limiting (and annoying) for general use (and would you trust Google anyway?), so why bother with a dual-boot set-up?

The solution is to get rid of all the originally-supplied firmware and ChromeOS and run Linux alone. This is being written on such a device. It works perfectly. I have played with various Linux CAD packages on this machine: all worked fine, as far as I could see.

**LINK**

This site has been devoted to running Linux on Chromebooks for several years and contains all you need for the conversion. I admit to not understanding all of the techy stuff, but following the instructions was easy and successful. I'm running GalliumOS, a light-weight Linux distro optimized for Chromebooks, on an Asus C200, now several years old. It's easier to replace the firmware on later machines. The whole process is reversible, should you wish to sell the machine as an unmolested Chromebook (but why would you?).

You can also do a similar trick to run Windoze on a Chromebook, but really...?

Edited By Kiwi Bloke on 11/01/2020 21:25:05

The ever-fascinating and obviously very capable Robin Renzetti has posted on Instagram a few pics of his conversion of a sensibly-priced reciprocating saw to a power scraper, and followed up with pics of apparently excellent results achieved. AFAIK, he hasn't written up a detailed 'how-to', but it certainly seems do-able, from the pics available. His multitude of other posts are also fascinating.

'Any advice' requested. Well, it all depends...

If you want the slips to be your workshop dimensional standard, you need to be able to ascertain that they are dimensionally within specification and they need to function correctly, i.e. wring together. A non-wringing, old set, out of spec., can, however be very useful in the 'shop, for some tasks, but it should be very cheap. Tungsten carbide and ceramic sets don't rust, but they chip. Sets can be calibrated and reconditioned - at a price.

Buying unseen off the 'Bay must be considered risky. Buying new is also risky, if the unbranded set is 'certificated' by an unknown outfit in the Orient...

My advice would be to get a new set, from a reputable manufacturer. Start saving now. Or get lucky at a sale, where you can check the set for 'wringability' (although not for accuracy, unless you carry an interferometer with you...). Then, of course, to get your money's worth from the slips, you'll need all the ancillary gear - surface plate, indicators, indicator stands, micrometers, rollers, balls, etc., etc. Start saving more...

Neat! I too will be waiting for the video!

'One of the useful implementations of the idea was the dual-reading Imperial/Metric dials on some milling tables; which had 125 and 127 tooth internal gears.' And, of course, Graham Meek's ingenious saddle handwheel dials (qv).

Edited By Kiwi Bloke on 11/12/2019 10:07:56

I'm sure you'll find a warm welcome here, Austin. There's a wealth of information here - most of it sound - and no-one need be shy about asking even the silliest-sounding questions.

Reading about the subject, before jumping in, is obviously a good idea. Tubal Cain was a true authority, but I don't think the author of your other book is in the same league. Unimat-related books by Rex Tingey are interesting, if only to see what determination can achieve in trying to overcome the limitations of the Unimat. If you search a bit, you'll find free downloadable copies of Unimat-related books on the 'net.

The unimat lathes are attractive, in a funny sort of way, and have been used to turn out impressive work. However, they are extremely limited in many important areas of performance and capability. I believe that it requires quite a bit of knowledge and experience to use them effectively, if only to be able to know what to try, in order to get around their limitations. I think there's a real risk that novices could get discouraged. The Cowells 90ME is much more capable, albeit at a silly price, new, with full factory back-up. If you can find a good-condition second-hand one, I don't think you'll lose money if you later decide to sell it. Perhaps that also goes for the Unimat, but the point is that, over the duration of ownership, both have a zero capital cost, but you would have got far more out of the Cowells. I own both.

Bigger lathes are easier to use and can do more...

Choochoo_baloo, I've PM'd you.

I've de-rusted quite a lot of steel components by immersion in molasses, with complete success, producing a bright finish, after the residual crud has been easily rubbed off. However, on some high-carbon steel items (gravers), the resulting finish has been dull grey, rather than the expected bright finish. I'm aware of warnings that air must be excluded from the surface to be treated, otherwise more corrosion occurs. I suppose it's possible that the soaked-tissue method allows oxygen to get to the surface, so perhaps the problem is further corrosion (oxidization), rather than etching (just material removal). However, this doesn't explain the poor finish achieved by immersing high-carbon steel.

I can only assume that the molasses sequesters some iron from the surface, leaving excess carbon, carbide, whatever, on/in the surface, dulling it. Or, perhaps, the grey represents black oxide, from rust conversion, in the 'pores' of the iron, which is consequently difficult to remove. Any chemists / metallurgists out there who know?

Have you tried to recover the cast-iron lustre by wire-brushing or using fine wire wool?

We discussed chelation in a previous thread, and I subsequently tried to find out more,only to discover that it's rather mysterious...

As above. It is surely a good idea to 'design' the handle to fail by bending before the vice is subject to excess force?

Have a look at this **LINK**

...and the follow-up on the DIY construction of a serious vice!

Well, Peter, you've just 'won' two weeks! What are you going to do with it? What would any of us do with an extra two weeks? Suggestions please...

I don't know about model engineering being in decline, but this model engineer has been for years...

Apart from not running off slide surfaces too readily, slideway oil is designed to have better 'stick-slip' properties than most other types of oil. It lubricates well when bearing speeds are very low ('boundary lubrication', IIRC) and there is insufficient film thickness to prevent metal-metal contact. Motor oils, etc, are generally used in hydrodynamic bearings, where a decent film thickness is built up by the relative movement of the bearing surfaces. Depending on dimensions and oil properties, this takes much more speed than slideways generally move at. So slideway oil is designed for the job, other oils aren't. Why use anything else?

A practical example: my Boxford shaper's ram judders horribly, because of the stick-slip phenomenon, unless lubricated with slideway oil. This is a hardly-worn machine, with the ram gib adjusted properly. Some molybdenum disulphide helps on some slideways, sometimes.

Edited By Kiwi Bloke on 21/10/2019 01:48:40

As above, plus...

Got any strongish acid? And if not, why not? Every self-respecting model engineer should have accumulated stocks of enough 'dangerous' materials to make a health and safety inspector hurriedly put on his bicycle clips...

Mild steel won't heat-harden, but will fizz in acid. Silver steel will heat harden and fizz in acid. Some stainless steels may harden a bit, but shouldn't fizz.

Dismantling is good, but a pair of scaffold poles or stout timbers under the stand's tray, orientated fore-and-aft, and lashed together so they are tight against the base make good lifting points for strops and a crane. It would be sensible to take the head off, though. I used this method when I moved an M1 and a Universal, with large table - both heavier than your machine. In fact, two hefty blokes can 'walk' one of these machines around quite easily, using the poles as handles. Four can lift it...

Edited By Kiwi Bloke on 18/10/2019 11:04:08

No need to make one - already got the ideal tool. Sandvik Bahco 8224 ratchet-adjustable pliers ('water pump pliers' ). The jaw shape holds the nuts well and its instant adjustment feature means that it can be set so that great force can be applied with minimal risk of movement over-shoot. But just give walnuts a smart rap with the back of a table-spoon. (Not expecting a prize...)

Edited By Kiwi Bloke on 18/10/2019 10:48:17

Michael, just be careful with Google - all your searches are stored, linked to your identity, as part of Google's 'big data' initiative. You have been probably been recorded as searching for a male model...

I need to correct my previous post. 7075 does seem to be a reasonable substitute for the high-strength alloy 'Dural', aka HE15, or 2024 (or 2014?). I had thought that it had inferior fatigue characteristics, but its mechanical properties seem just a little better than those of 2024 and its corrosion resistance is much better. Apologies for any confusion caused.