Here is a list of all the postings Mick B1 has made in our forums. Click on a thread name to jump to the thread.
|Thread: What’s the tolerance??|
When I was working as a Tool Designer, the drawing sheet blanks (some kind of coated film that had enough friction to take good pencil markings) all had standard printed boxes bearing 'tooling Req. no.', 'drawn by', 'checked by', projection, title, tool no. etc., alongside a list of General Tolerances. These were (IIRC) no decimal +/-0,25mm, 1 decimal 0,1mm, 2 decimal 0,025mm, 3 decimal as specified. That meant that if a particular precise value was required - for example detailing punch and die dimensions for press tools - the draughter should normally specify top and bottom limits fully. But there were still often grey areas, and not only where some Industrial Engineer came along and smudged your drawing by carelessly pointing out some feature with a grubby finger !
I think that for most ME applications, it wouldn't be practical or sensible to specify every dimension exhaustively, so what you usually get is more or less what's needed, although many force the builder to work out values that could helpfully be noted as '(Ref.)' dimensions. A general guide as to piston/cylinder and shaft/bearing clearances would be useful on many.
Edited By Mick B1 on 04/07/2020 11:53:31
|Thread: Downwards-Counting Cross-slide Dial?|
It's just another designer's smartypants idea. My Warco counts double the actual movement on the crossslide because it's calibrated on diameter.
I find these 'aids' just a minor irritation - another b100dy thing to remember - but you get used to them.
I'd slightly prefer the simplicity of the Navy method - signal the raw data and leave it to the person on the spot to do the interpretation. Once you put a spin on it, you're as likely to complicate his job as simplify it. That way you don't have to do different arithmetic depending which slide you're using.
Edited By Mick B1 on 03/07/2020 10:17:58
|Thread: WM250 Sticky Carriage|
One possibility is that someone in testing has run the power feed against a locked carriage, and bent the carriage pinion shank.
That's what I did within a week of receiving my WM250V.
You can fix it with a crowbar, thus:-
Use the toe-end of the crowbar, and wind the carriage as far as you can toward the tailstock, and stop at the stiffest sticking-point.
Set the toe of the crowbar against the top of the pinion shank, and lever upwards to bend the pinion downwards, out of tight mesh. Use moderate force.
Of course your lathe is new and you mayn't want to try that - but my WM250 hasn't shown any problems - other than of my own making - since I did that, and it cured the sticking carriage completely and with no side-effects.
So you might save yourself a good deal of hassle with a few minutes' experimentation.
|Thread: Brian's Twin Beam Stirling Engine|
That's an astonishing and really delightful piece of work.
The lighting is so uniform that I thought at first I was looking at a piece of CGI, but that idea soon evaporated.
Is that your own design, or adapted/modified from some established pattern? Amazing either way.
|Thread: Digital angle gauges|
When I was larnin' in the 70s, a M&W Vernier protractor, reading to 5 min. was the effective limit of workshop angular measuring accuracy. Perhaps you might've done a little better with a top-of-the-range dividing head setup. That's not a whole lot better than 0.1 degrees. A friend gave me an old one about 10 years ago and I cleaned it up and use it now and again.
I've also got a 0.1 degree PowerFix thing from Lidl, but you have to zero that first against a known flat surface.
But I'm not sure in the model eng. world what would make you need better?
Edited By Mick B1 on 22/06/2020 13:59:49
|Thread: ...I'll just finish up this part..|
Although it's a completely separate subject, your story reminds me of one I used to be able to tell about what it took to get the Oracle 11i business system to actually create an invoice after having despatched a sales order...
|Thread: machining acetal|
If the tool's sharp it hardly matters. I slot-drill a 1/4" square slot across a ~ 2" diameter acetal cap now and again, and find it pays to use a fine feed for easy deburring.
|Thread: Stuart 10V Build Log - Complete Beginner...|
IIRC the calc's on the back of the Zeus booklet. I made my top end cap out of phosphor bronze - I thought it might look nicer. It did for a year or three - now it looks like lightly-rusted steel. But the phosphor bronze tyre I shrink-fitted on the flywheel still looks good.
|Thread: Can summer car tyres be used in winter?|
Sorry, but there's so much entertainment and clever verbiage in that clip that it obscures any truth or relevance it might have.
My experience matches the bloke's he dissed - nitrogen reduced pressure loss. I didn't notice any difference to anything else. I got charged (IIRC) 50p a tyre for nitrogen on buying the tyres, and was told it was OK to use air to top up, so that's what I did on the fewer occasions it was necessary. Where I live now, I can't seem to find nitrogen anywhere I visit often, and I'm certainly not gonna waste my life looking for it, so I'm back on air.
Now, he may or may not be technically right, but it's worth remembering that You Tube influencers are in the business of gathering followers and acolytes too, so it's ok to take what they say with the tiniest pinch of salt.
You can say you follow the science, but it depends to some extent on who's paying for the research.
|Thread: Best places to buy metal for machining|
I've also had good deals from Aluminium Droitwich, though as I lived in Redditch at the time I was tending to buy over the counter. They also sold me some acetyl (Delrin-like) at a very competitive price.
Now that I'm in Staffs, I've found Macc Models a very reliable supplier, and I'm very sure everything has been what they said it was.
|Thread: Wooden Gears|
Purpleheart is quite attractive and close-grained.
But the missus thinks it smells of sick...
|Thread: Does anyone view this forum by first selecting a 'topic'?|
I'm another who uses mainly Latest Posts, but this is a broad enough field to have people in it who confine their interests to subsets of the whole. Why shouldn't they have the capability to filter by topic if they want, providing posters are disciplined enough to categorise properly?
|Thread: Ultrasonic toothbrushes|
In the 60s there was a cat food called (IIRC) 'Dine' which was a canfull of silvery compressed whole fish in jelly.
Fluff loved it, but parents wouldn't buy it having seen (and smelt) it once.
|Thread: Drill sharpening?|
When I was learning in the 70s everyone was simply expected to learn to offhand-grind their own drills. Tool'n'cutter grinding machines were for toolroom use and shopfloor turners didn't expect to have access to them.
I can't remember whether it cost me 1 day or 3 to learn the technique, but I've never thought a drill grinding jig or machine was worth either the purchase price or the time spent learning it and setting it up - better just to wander over to the bench grinder for a few minutes. Do it decently and the drill will cut to size from solid within a thou or so, and drill many tens or perhaps hundreds of holes before you need to regrind it.
|Thread: MEM Corliss progress|
Flywheel looks machined from solid - is that what you did?
I keep wondering if I'll ever put together the time or commitment to tackle the complexity of a Corliss...
|Thread: Parting off|
If there are proper side clearance angles down the blade, the most likely causes are
i) the blade isn't set parallel to the movement of the crossslide. I eye mine up mine against the crossslide T-slots, but not all lathes have those.
ii) The tool or blade isn't vertical with respect to the spindle and bed, so the side clearance angles are defeated.
iii) If top rake has been obtained by grinding a short dip in the upper flat of the blade, when the runout of that dip enters the work, it's likely the tool blade at that point is wider than the cutting face because the latter is lower down the taper.
iv) If the tool cutting face has been ground at an angle, typically to minimise the pip on the parted component, the chips will be wider than the tool, and may jam if there are conditions that rotate them across the slot.
Edited By Mick B1 on 08/06/2020 17:37:50
|Thread: Questions about lathe power feeds.|
As I said above, it's extremely useful if you do milling in the lathe. If you reverse the feed knob it retracts the crossslide just as the sliding feed would work towards the tailstock.
I liked Chapman's 'Workshop Technology'. It's 3 volumes, but everything's there, it's readable, and you'll keep coming back to it for years (actually decades in my case).
|Thread: Questions about lathe power feeds.|
Yes, but I'm grateful for it on my Warco because powered crossfeed enables fine milling on the vertical slide. The machine would be materially less versatile without it.
Edited By Mick B1 on 06/06/2020 16:13:57
|Thread: rescuing a chuck|
Looking at the jaws on the cheap Chinese chuck on my Warco, it's readily apparent that the damage seen in Niall's chuck would be very unlikely to occur, because all the scroll teeth are the full width of the jaw - none of them are on the triangle down to the grip face.
The Pratt Burnerd 3-jaw on the Myford Speed 10 I used to have showed the similar damage from when I bought it, and I've seen it on many other SC chucks.
I'm suspecting that (at least some) more recent designs are circumventing this vulnerability. It means sacrificing some capacity at the limit - and doing the changeover to external jaws at a lower diameter - or else positioning or extending the scroll further towards the chuck periphery. It looks a beneficial change to me.
Edited By Mick B1 on 06/06/2020 16:05:39
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