Here is a list of all the postings Hopper has made in our forums. Click on a thread name to jump to the thread.
|Thread: Colchester Headstock Sleeve|
With the difference between a Morse and Jarno taper being in most cases within .001" to .002" per inch, it's quite possible that the one will fit the other in a short application like the headstock collar, without the mismatch being noticed?
|Thread: Submitting Articles to Model Engineers' Workshop|
I can confirm the ease of use of WeTransfer from the submitter's end. Very simple to use and totally effective. Makes sending multiple photos over the net a pleasure instead of a chore.
|Thread: New coffee maker - disgusting taste!|
You haven't lived until you've tried Tibetan butter tea. Ingredients: Tea, hot water, yak butter and salt. Came across it in Nepal recently. It's different.
|Thread: Buying lathes direct from China|
I've a mate who bought a minilathe direct from China. But when I looked into doing the same it seemed that with the shipping costs and various fees and taxes it was not much cheaper than buying locally. Not enough to make it worth taking a punt on no warranty, no return, no service etc.
If it were a screaming bargain to import a lathe direct from China I would expect many people would be doing it -- which they aren't. In this day and age of internet commerce that pretty much says it all.
|Thread: Making Bevel Gears|
See the discussion here, further down the page **LINK**
|Thread: releasing tapers|
Agreed. The tiny MT1 taper on my old Drummond M-Type tends to let go occasionally when the old Flagellator is pushed hard. So much so that the ancient drill chuck that came with it finally would no longer grip. All the wear, corrosion and dents fom over the years were on the taper shank on the chuck. Inside of the tailstock barrel seems just fine. As pic posted way above shows, new chuck with new taper shank will hold a 1" drill firm without slipping. I don't think a spinning taper every now and then is a catastrophic problem.
I never cease to amaze myself. An unconscious genius, I tells ya.
|Thread: Upgrade from SC3 lathe|
Wise move. I would not buy sight-unseen unless the price was rockbottom giveaway low.
The thing with buying used is you have to be prepared to put the time in to wait for good machine to come up at a good price. New is certainly the convenient option.
Perhaps revisit your original idea in your first post and think about a Boxford? A low mileage example would be a good machine. Perhaps get some help via the forum with finding or inspecting a good example? Or one from a dealer with some kind of guarantee or warranty?
I know the Australian equivalent South Bend clone, the Hercus, is a very good machine, having used them over the years at various jobs and tech college etc. They are good and solid. Sort of the next size up from a Myford.
Also a good used Raglan would be worth looking into as well.
|Thread: ML10 tailstock|
Well done. That's a good result. Our ML7 is much the same: when releasing the lock handle you have to give it a tap with the palm of your hand to make sure the locking blocks have released their grip on the quill. Seems to be nature of the beast. Your measurements look good. Half a thou is nothing to worry about.
Carry on lathing!
|Thread: Alternative materials|
Last little mill engine I built used brass for the eccentric strap, on a steel eccentric. No problems.
|Thread: ML10 tailstock|
Not sure on the ML10 but on the ML7 the key has a round pin sticking out the side of it that goes into a round hole in the tailstock body. You can see the end of the pin if you scrape the paint off the outside of the tailstock body next to the key. Tap the end of the round pin with a hammer and small drift and the key should pop out into the bore of the tailstock.
|Thread: releasing tapers|
Methinks pressure waves in soft lead bullets under the power of explosive gunpowder may be a different kettle of fish from a tap with a tapered drift on a tough tool steel taper shank. Hard to imagine similar amounts of deformation going on. Maybe to a certain extent? Maybe. But more likely you just tap the thing and its pushed out.
Edited By Hopper on 12/02/2019 10:06:48
|Thread: ML10 tailstock|
Rather than any magical swelling of the solid steel quill at each end, your stiffness of motion is more likely to be due to something like burrs along the keyway slot that the guiding key slides in, or burrs or even just sharp edges on the key itself. Possibly burrs on the ends of the quill, especially if a hammer or drift have been applied to get it to move during the removal/replacement process. Also burrs in the inside of the tailstock body where the quill slides should be checked.
Go over the whole lot with a small fine file and remove all burrs and sharp corners and sharp edges then give a thorough cleaning to get rid of filings etc.
Also check the locking blocks for same and make sure they are physically pushed back out of the way and not dragging on the quill when checking for freedom of motion.
You should be able to leave the guiding key, quill locking blocks and handwheel etc off and push the quill in and out of the tailstock body by hand with no resistance. If it doesn't, that indicates some burrs etc on the main diameter that need removing. Otherwise, keep adding one component at a time until binding occurs and that should indicate where the problem lies.
Edited By Hopper on 12/02/2019 10:02:31
|Thread: releasing tapers|
NDIY raises a good point indeed. Why a tang captive in a slot and unable to rotate if purpose, as has traditionally been claimed, is merely ejection? A round hump would indeed do the same job for ejection purposes.
Is it like the woodruff key used on a tapered shaft where it fits in a tapered hole, as commonly used on motorbike engine sprockets etc? The drive, supposedly, is all by the taper. But the key, as traditionally claimed, is there just in case the taper lets go momentarily. It supposedly holds the pieces in place so the taper can pick up its grip again.
In this case, I don't think the woodruff key alone would transmit the full power of a, say, 80hp engine if the shaft were a parallel sliding fit in the sprocket so all load was on the key. But its enough to hold the tapered pieces in line if they begin to partially lose their grip.
So maybe the tang acts the same way? It won't transmit the full power as evidenced by drills with snapped off tangs. But it could be just enough to catch a slightly shifting taper before it fully lets loose, and allow it to regain its grip?
Can't find any specific reference in Machinery's Handbook or others either way. Would be interesting to learn where the traditional wisdom originated.
Edited By Hopper on 11/02/2019 10:48:17
Yep. Tang is not designed to transmit load, ie stop rotation. I've seen more than one tang twisted off on large drill bits over the years where the taper was not doing the driving due to swarf, damage etc. The tang is put there for ejection purposes.
|Thread: Every Tea Room needs a toaster topic...|
I liked the bit where he enlarged the gap in the bed with a hacksaw to accommodate the Indian's longstroke flywheels. There is a new book out on him recently, a series of "lost" interviews with him done back in the 60s but the reporter never published them until his lost notebooks were found by family just recently. The story in the movie and associated book was just the tip of the iceberg when you read about some of his other antics.
I knew a woman who was once a cadet photographer at Burt's local newspaper and used to photo Burt/Bert every year before he went to Bonneville. She reckoned he was every bit as crusty as this photo suggests. Slept in a bed in his workshop, with a tarp over it because the roof leaked. Reckons he had a pot of stew bubbling on a burner in the corner that he just added a bit to every day to keep it going. She reckoned it was the same stew bubbling away every year she took his photo for the paper.
But with that "crappy Myford" he did some amazing stuff. Not just machining his own pistons, heads and barrels but also converting the Indian from single cam to double or quad cam configuration - some major surgery.
Edited By Hopper on 09/02/2019 11:21:45
Actually it's a funny thing about toast and some fire alarms. There is something in the fumes that come off toast that will set off fire alarms before the toast even starts to smoke. I know this from some years of being a night shift engineer in a hospital where nurses would try to sneak a toaster into their work station and cook toast in the wee hours instead of using the kitchen. Gave them a hell of a wake up call when the alarms went off building-wide, the fire department arrived and myself and fire chief would have to sight the offending fire sensor and ascertain cause of alarm. Usually the lingering smell of toast and the petrified expressions on the responsible nurses' face was a giveaway.
You should hang on to it, just incase you ever want to build a life-size recreation of Burt Munro's "Worlds fastest Indian" workshop. (See background just over Burt's left shoulder.) Handily located next to the trusty Myford so toasted Vegemite sandwiches could be made while taking long cuts on motorcycle cylinders etc.
Looks like the ones I remember in use when I was a lad in the 1960s. So they probably dated back to the 1950s as things never wore out and people never threw things away in those days.
ISTR you have to flip the side down rather quickly for the automatic flip function to work.
More clearly I remember well the sound of the edge of a knife scraping the charcoal off slices of burnt toast into the sink in the morning. Pretty much a daily occurrence before pop-up toasters saved the world.
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