John, watching you sanding on what looks like a solid metal block, you might be able to answer a question. I do metalwork as a hobby. I recently got two solid steel blocks, which appear precision ground. They measure 3X1.25X12 inches. Do you happen to know for what use they were intended. Thanks
Large parallels for a milling machine? The large block of metal John was grinding on is a magnetic chuck off of a surface grinder, probably the surface was beyond repair so had been scrapped from it's original use. Ideal for de drossing plasma cutouts.
@@65cj55 to repeat repeat the logic doesn't hold up, the reamer is only meant to cut in the case of a machine reamer on the short section at the very tip and a hand reamer by the short section about 1/2 to 2/3 diameter again at the end. The flutes are meant to guide and not cut, all the cutting as done at the very front, very much like a drill Once a reamer has been withdrawn a few thou the cutting section is no longer in contact and therefore shouldn't cut! They are many myths spouted by old timers that don't hold truth, like a file pulled backwards will be blunted while still in contact or the need to have the compound slide moved at half pitch angle to cut a thread. As I asked why worry about a reamer going backwards when you don't about a tap, which also only meant to cut at the front. One should not believe all myths till you understand why and only then accept them. I am quite prepared to change my view upon superior knowledge, but Google is not to be relied upon 100% of the time.
Thanks John, I always look forwards to this part of my Sunday....
Just wonder what the concentricity of the alternator drive joint will be like... I suppose the shaft speed won't be that high.
Nice Touch on the world war 2 helmet and rifle John.
Thanks John
Very good.
Good work John.
Great job John 👋👍🇬🇧
John, watching you sanding on what looks like a solid metal block, you might be able to answer a question. I do metalwork as a hobby.
I recently got two solid steel blocks, which appear precision ground.
They measure 3X1.25X12 inches. Do you happen to know for what use they were intended.
Thanks
Large parallels for a milling machine?
The large block of metal John was grinding on is a magnetic chuck off of a surface grinder, probably the surface was beyond repair so had been scrapped from it's original use. Ideal for de drossing plasma cutouts.
Many thanks
as per brill
I have often heard about not turning reamers backwards, but the logic foes not hold. Should one worry about turning a tap backwards?
Use your Google..
@@65cj55 to repeat repeat the logic doesn't hold up, the reamer is only meant to cut in the case of a machine reamer on the short section at the very tip and a hand reamer by the short section about 1/2 to 2/3 diameter again at the end. The flutes are meant to guide and not cut, all the cutting as done at the very front, very much like a drill Once a reamer has been withdrawn a few thou the cutting section is no longer in contact and therefore shouldn't cut!
They are many myths spouted by old timers that don't hold truth, like a file pulled backwards will be blunted while still in contact or the need to have the compound slide moved at half pitch angle to cut a thread. As I asked why worry about a reamer going backwards when you don't about a tap, which also only meant to cut at the front.
One should not believe all myths till you understand why and only then accept them.
I am quite prepared to change my view upon superior knowledge, but Google is not to be relied upon 100% of the time.