Member postings for lfoggy

Has anyone read this?

Exactly: How Precision Engineers Created the modern world. By Simon Winchester.

https://www.amazon.co.uk/Exactly-Precision-Engineers-Created-Modern-ebook/dp/B076FTNNXN

Have just ordered it and am looking forward to reading it...

I had one of these in my workshop for a couple of years and I was very glad to see the back of it when I replaced it with a bandsaw. Mine was painfully slow with limited capacity and sometimes it just wouldn't cut at all unless you hung weights on the bow to increase downforce. Really only useful if you have a lot of patience and small amounts to cut !

There are two gears on the indicator and you choose the one appropriate for the pitch you are cutting. The gear is selected by undoing a nut, removing and replacing the gear. As stated above, as long as the tooth count is correct it wont matter too much if the tooth profile on the gears is not perfect. If you are planning to do a lot of thread cutting I think making an indicator is definitely a realistic prospect.

I have a metric 254 with the 3mm pitch leadscrew and it has an indicator fitted for cutting metric threads. It is a simple device and it would be possible to make one. It is basically a metal body which holds a gear against the leadscrew. There are two gears to choose from (28 and 30 tooth) depending on what pitch you are cutting. There is a dial with divisions connected to the gears that then indicates when to re-engage the half nuts. The metal body would be basic machining and you would need to be able to cut the gears You would need to find an original to copy, particularly for the divisions on the dial.

If you are anywhere near Birmingham you are welcome to inspect and measure up mine....

I purchased several sets of knurling wheels for my Hemingway tool from Zoro.co.uk. These are excellent quality. I now have fine. medium, coarse diamond knurls and fine straight knurls. The tool struggles with the coarse knurls on steels but is OK on brass and aluminum. The fine and medium cut well on steel. I seem to recall that Hemingway were only selling fine knurls, at least when I purchased my kit a few years ago.

I ordered a set of ER collets from ARC a few months ago and they sent me the wrong sizes. Although apologetic they said they could only replace them once they had received the incorrect ones back and asked me to post them. As I work full time this was a significant inconvenience. I did suggest that they arrange for the replacement items to be delivered and the wrong items collected at the same time but this was rejected. I was slightly disappointed that they were essentially transferring the hassle of remedying their error to me. Did eventually receive the correct items but still waiting for the promised refund of the return postage.......

Yes, there is a long discourse on the theory of the fusee curve and the text does state the diameter at the big end and the small end of the fusee but there is no actual plan of either fusee and details of the recess for the maintaining power on the time fusee is left out. I did wonder is there were some pages missing from my book but i dont think so.

The dimensions are all very odd as well. My favourite so far is a part that calls for a 3.658mm hole. I know modern drills are accurate but that could be a challenge. Presumably that is some converted Imperial dimension...

Anyway, plates and pillars now complete, barrels and fusees next.

I've just made a start on building the English style bracket clock described by John Tyler and am wondering if anyone else has built this?

I've made a few clocks before and purchased the book more for the plans than for the instructions. In spite of the rather long and wordy nature of the book I am finding it a little difficult to follow. There is a distinct lack of dimensioned drawings, a bizarre use of metric dimensions (which are just direct conversion of imperial dimensions often given to three decimal places!) and almost complete lack of any assembly diagrams. The two fusees for example are described in the text but there are no drawings of them which is odd.

I am anticipating lots of head scratching ahead. If anyone has any detailed photographs or plans of the movement, that would be very helpful, as would any other tips or advice.

Incidentally, I am also planning to use ball races instead of pivots on this clock like I did with an English regulator I completed a few years ago. This worked very well.

Thanks

I've got a Chester 830VS which is single phase with an R8 taper. Perfect for my requirements and workshop size constraints. Its not got quite enough travel to mill 20 inches in one pass but you can certainly get a 30cm workpiece parallel to 0.02mm quite easily. Probably do better than that with a bit of care holding the workpiece..

Lacks a power feed for the quill though and that's next on my project list....

Wow, your workshop facilities sound amazing.

My 830VS has continously variable speed from 0 to 2250. No back gear, just direct drive to the spindle via a single pulley and an inverted drive to the motor. The machine is however advertised as having a speed range of 200 - 2250 implying that speeds under 200 shouldn't be used. Chester themselves seemed unable to advise whether using the low speeds was permisable. Torque at very low speeds is still good however and I have used the machine with a flycutter at 50rpm without a problem so it seems to work ok.

Edited By lfoggy on 28/07/2019 14:12:01

Hi John,

Welcome to the forum. The Stuart 10v is a great model engine and I've built several over the years.In fact there is one on my desk as I type that I built over 30 years ago.

I'm in south Birmingham so happy help if you need any assistance.

Regards

Those are all generic warnings so could be almost anything. I was going to guess sodium chloride as well but I will say sodium bicarbonate.

My Chester 830VS is the model with the round ram which makes it very versatile. I agree price is a bit high but managed to negotiate a 10% discount and free delivery (maybe becuase I am very close to their warehouse) whhich helped. Speed range is continously variable 200-2250. I am planning to add a few more pulleys to give a very low speed option and a higher speed option but for 95% of my work the standard speed range is excellent. The machine is built in Taiwan, not mainland China and build quality is very good compared to other machines from Chester and Warco. Hence the higher price....

I bought a Chester 830VS last year and I'm sure it would be more than adequate for what you describe as well as being a little more compact than the Chester 836 or Warco VM20 if your workshop is tight for space as mine is.

Happy to provide more info if required....

I use 10mm and 12mm tools on mine with the original Myford quick change tool post.

Magnetism in the probe can be a real nuisance with wigglers. Even a minor degree of magnetism can give erratic and inaccurate results on ferrous metals. My workshop seems to have become annoyingly magnetic recently and I am having to de-magnetise frequently.

Thanks for the comments. I couldn't be bothered to return them so I used a carbide tipped boring bar to relocate and enlarge the bore to 26.5mm. Made another arbor out of an R8 blank I had and they now run very true and cut ok. I suspect my 26.5mm arbor will come in useful again sometime.

I've recently purchased two slitting saws from different well known UK model engineering vendors. Both were 4 inch in diameter with a 1 inch bore and widths were 2.5mm and 3/32. Both saws were significantly out of true when rotating, one by 0.9mm and the other by 0.5 mm. My arbor has a negligible degree of runout so the problem is the bore of the saw is not concentric with the periphery. That degree of eccentricity means that they only cut on a small proportion of the teeth. Useless really.

How can this degree of inaccuracy even happen in the manufacturing process? I would have thought the blade is mounted by the central bore for the final grinding of the teeth...

Anyway, they were inexpensive saws at less than £10 each so maybe this is a case of 'you pays your money and you takes your choice'. All the other saws in my collection come from old UK made stock and run perfectly true. Industrial suppliers charge 3 to 5 times more for new sliiting saws but maybe thats what you have to pay?