Member postings for Mike Crossfield

Alan

Yes, I did sort it out. What I found was that when you enter the PCD Function and the CT POS display comes up you MUST enter values for X and Y, even if they are both zero and the display is already showing zero. You can’t just press enter and move on to the next setting. To be fair it does show this in the manual (steps 3 and 4 in the version I have), but it wasn’t clear - to me at least - that you need to enter zero if the display is already showing zero.

Hope this works for you too.

Mike

I use 68 grade Slideway Oil. As with all my lubricants, I buy it from Smith and Allan. Great service and low prices. 5 litres Slideway Oil is £11.55 plus vat and carriage. 5 litres lasts me 5 years+. I try to order a number of items (Slideway oil, cutting oil, spindle oil, paint etc) at the same time to spread carriage cost.

I built Steve Ward’s excellent design of controller a few years ago. Very well documented and simple to build using a programmed PIC and pcb available from Steve at very low cost (Full kits also available). Regarding William’s original question, Steve answered this with respect to his own design in response to someone else’s question a few years ago. I quote:

“So basically internally it multiplies the number of divisions by the actual division its on then divides the result by the number of steps for a full circle - this gives it the nearest number of steps it needs to get to that division (doing the multiply first prevents loss of resolution although it means it needs 32 bit maths which is why the max steps per rev is 16 bit).
Internally it knows exactly how many steps it's currently taken so simply adds (or subtracts) that from the answer above to get the number of steps to take.

This means there isn't a constant number of steps since it may need to take an extra step (or lose one to be accurate).

In practice the accuracy of the maths is half the single step resolution, so a 400 step driver on a 90:1 worm gives you 0.01 degrees per step so the accuracy is 0.005 degrees. (Mechanical accuracy not withstanding)”

HTH

“The guy on the TV is an idiot”

That’s a bit harsh Bazyle. I saw the programme mentioned, and what the chap said was that people often say a clock has been “overwound”, but that’s often not the problem, and one would have to really strain on the key to do damage. Sure, springs can break in normal usage, but the comment was not unreasonable. And from the apparent quality of work that the man in question does, and his 40 years experience of clock repairs, he should know what he’s talking about.

I have a Kerry Super drill which I bought and renovated about 20 years ago. It was in a pretty neglected state, but cleaned up well and I would never part with it. There is a photo in my album, but unfortunately it doesn’t show the side with the return spring housing. When I got the machine the original return spring cover was missing, but fortunately the clock-type spring was still there. I turned up a new cover out of ally, and it’s been fine ever since. The inner of the spring fits into the slotted end of the quill operating spindle, and the outer end fits into a slot in the cover. The cover is a shallow “cup” which the spring sits in, rather like the barrel of a clock. To tension the spring the cover is rotated in its housing in the drill casting, then locked with a grub screw. No drama taking it apart. Just release the grub screw while holding the cover and release the tension. The cover can then be pulled off complete with the internal spring.

Mike

Gray

if you search on eBay for “3 axis stand alone stepper motor controller” you will find several Chinese suppliers.

As the old saying goes - "the man who never made a mistake never made anything".

Mike

My late 50s Super 7 is the same as John’s, the belt cover rubs on the lever if it’s opened in the “engaged” position.

Mike

That’s interesting. The reason I asked was that a rule of thumb I was given some time ago was a chip load 1% of cutter diameter. This this has worked out ok for me in the past. For a 2 mm cutter that suggests .02 mm, just under a thou.

The correct shims are made up of a laminated stack, each individual shim being 2 thou thick. To reduce the thickness, and remove play, shins can be peeled off the stack with a sharp knife. It could be that the previous owner has removed too much, and compensated by leaving the clamping screws loose. You could buy new shims, but I would be inclined to try adding some extra shim material until you get the required clearance.

I was taught to take the car out of gear and apply the hand brake if stationary for more than a few seconds, and regards it as sloppy and inconsiderate driving to hold the car on the footbrake. However you do see it quite a lot, particularly with young drivers. Maybe something to do with the way they are now taught? Another issue is that some modern cars (like my latest) have an “auto hold” or “hold assist” feature which keeps the brakes applied hydraulically when the car is braked to a stop, so no need to apply the parking brake in temporary stopping situations (these cars generally don’t have a conventional manual hand brake). The consequence is that the brake lights stay on, even though the driver does not have his foot on the brake. When I discovered this I found that I could over-ride the Autohold by applying the Electronic Parking Brake, thereby turning the lights off. Interestingly, from threads on motoring forums I belong to, quite a few users aren’t aware that Autohold leaves their brake lights on. This ought to be made clear in the Manual for the car, but it isn’t. I have it on good authority that the salesmen at some main dealers don’t know about this either.

Definitely invest in a better brush. I use Hamilton Perfection Pure Bristle. Less than a tenner on eBay for a 2 inch, or you can get a set of 4 different sizes for about £25.

I spent my early childhood in the North West near Bury, and many local dialect terms abounded. One which springs to mind, and was capable of dangerous confusion, was the use of “while” to mean “until”. Example: ”wait here while I come back” meaning wait here until I come back. The story goes that a “southerner” working in a factory boiler house was told “don’t light the boiler while water’s in”. The consequences were predicable!

Rainbow

Your preparation sounds good, though you don’t say how you rub down between coats. For the very best finish I use 400 or 600 grit wet and dry paper and soapy water between coats to remove minor imperfections and brush marks. Use a cork or rubber backing block where feasible. As has been already said, a really good pure bristle brush of the right size makes a big difference if you’re applying by hand, and a slow drying paint will make it easy to keep a wet edge and allow brush marks to flow out. I’m a big fan of Tractol paint, which is capable of excellent results when hand applied, and is tough as old boots. Even better if you have spraying facilities.

Do check carefully when looking at courier delivery costs. I recently shipped two items, one 7kg, the other 14kg. In both cases the initial prices that popped up on Parcel2go looked very good £8 and £9 respectively. However insurance for £200 more than doubled the cost, then VAT added another 20%, so final costs were £20 odd.

A search for “self bonding copper wire” will give you dozens of hits. Many self bonding enamelled wires are directly solderable.

The design of the bulb can also make a difference depending on the style of the light fitting. Many led replacement bulbs have a blank section at the base, so the radiant arc is mainly upwards. Ok for pendants, but not so good for table lights, standard lamps and ceiling fittings where the bulbs point upwards. I’ve taken to using filament-style led bulbs which mimic old style incandescent bulbs and have a much bigger radiant arc. Last ones I got were 8 watt and are subjectively much better than 60 watt incandescent bulbs. A bit pricey, but if they last as long as advertised they will pay for themselves in power saving.

Thanks Gray

i was pretty sure that your original data would have been spot on.

Looking forward to the second article, and making my own version of the dial.

Regards

Mike

I’ve just been reading the first part of the article in MEW 279 describing Graham Meek’s tailstock dial for the Myford S7, and noticed some obvious errors and omissions in the details of the gear cutters (figures 4 and 5). In figure 4 the r1.38 dimension for the 48 tooth cutter cannot be correct. In figure 5 the r1.5 dimension for the 54 tooth cutter is also clearly wrong. In all cases no dimension is specified for the cutter widths.