Here is a list of all the postings Mike Crossfield has made in our forums. Click on a thread name to jump to the thread.
|Thread: Cheap ER collet advice please|
I’ve bought ER25 collets a couple of times from CTC and been very happy with the quality and price. The chap running the operation in China, a German, was very helpful when I had some queries and wanted a special size. In my experience, accuracy doesn’t seems to be far from the stated 0.4 thou runout with everything carefully cleaned.
I make all the wheels (and pinions for that matter) for my clocks using home-made cutters. I use a variation of the “button” method to make the cutters. I start out with a cutter in the form of a parting tool ground to an accurate width with a semicircular tip. I use this to cut the wheel/pinion cutter from round silver steel. The centre fixing hole is offset to create cutting clearance. After parting off, a segment of the disc is removed to create the cutting edge, and the cutter is hardened and tempered. Then away you go. Brass wheels are easy to cut in a single pass with the mill running flat out (2000 rpm). Steel pinions are harder, and I typically take 3 or 4 passes running at 200rpm, and using lots of cutting oil. I get all my cutter geometry data from the very useful table in the Meadows and Passmore catalogue
Examples of a wheel cutter, a pinion cutter, and some wheels and pinions cut for my latest clock are shown below.
|Thread: Up and over door seal|
I have a strip of the damp proof plastic membrane that bricklayers use fixed to the bottom inside face of my up and over garage doors. I used self tappers and washers to fix. Very flexible, weather-proof and cheap as chips. Works a treat for keeping out wind blown rain and leaves.
|Thread: ML7 lathe carriage|
I dowelled the saddle gib on my early Super 7 about 20 years ago after reading an item by either GHT or Jack Redford. It was certainly an improvement, and allowed the gib to be set very closely without tightening up when the saddle was moved. Interestingly, Myford changed the gib design on later models so that one of the screws provided the equivalent of a dowel function. However I don’t believe this was carried across to the ML7.
|Thread: What method do you use to find center height for your lathe bit?|
20-odd years ago I made George Thomas’ centre height gauge. Very nice design which can be used from the bed or the top of the cross slide. I use it all the time and can highly recommend it.
|Thread: Sino SDS-2MS Dro problems|
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.
|Thread: What are you using for Lathe Way Oil?|
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.
|Thread: Electronic Indexers - How Is Cumulative Error Avoided?|
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).
|Thread: Rusty Clock Springs|
“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.
|Thread: kerry super 8 bench drill|
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.
|Thread: Stand alone controller|
if you search on eBay for “3 axis stand alone stepper motor controller” you will find several Chinese suppliers.
|Thread: Ever have one of those days..?|
As the old saying goes - "the man who never made a mistake never made anything".
|Thread: Myford Clutch Lever fouls the Belt Cover|
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.
|Thread: Milling Brass|
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.
|Thread: ML7 Carriage shims and wear|
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.
|Thread: The Chocolate Fireguard as designed by Mercedes Benz|
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.
|Thread: How to get that high end paint finish|
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.
|Thread: Dialect expressions|
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!
|Thread: How to get that high end paint finish|
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.
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