Home |
Search |
Today's Posts |
|
Metalworking (rec.crafts.metalworking) Discuss various aspects of working with metal, such as machining, welding, metal joining, screwing, casting, hardening/tempering, blacksmithing/forging, spinning and hammer work, sheet metal work. |
Reply |
|
LinkBack | Thread Tools | Display Modes |
#1
Posted to rec.crafts.metalworking
|
|||
|
|||
Anyone want a decent but big Surface Grinder? So. Cal
On Sun, 14 Nov 2010 17:30:09 -0800, Gunner Asch
wrote: This one runs ok, but is dirty and nasty. The 6x18 magnetic chuck needs repair..a pin inside has come loose and it doesnt go fully into Engage position. Not a big deal I've got a fine pole magnetic chuck that doesn't work as well as I suspect it should - there are strong areas and weak areas. I"ve read various opinions on the web regarding whether it's safe to take them apart versus those which say they'll lose their magnetism and be ruined. How do you tell if the one you're working on will lose its magnetism if you open it? The chuck in question is a Magnetool, from Hazel Park, MI. RWL |
#2
Posted to rec.crafts.metalworking
|
|||
|
|||
Anyone want a decent but big Surface Grinder? So. Cal
GeoLane at PTD dot NET GeoLane at PTD dot NET wrote:
On Sun, 14 Nov 2010 17:30:09 -0800, Gunner Asch wrote: This one runs ok, but is dirty and nasty. The 6x18 magnetic chuck needs repair..a pin inside has come loose and it doesnt go fully into Engage position. Not a big deal I've got a fine pole magnetic chuck that doesn't work as well as I suspect it should - there are strong areas and weak areas. I"ve read various opinions on the web regarding whether it's safe to take them apart versus those which say they'll lose their magnetism and be ruined. How do you tell if the one you're working on will lose its magnetism if you open it? The chuck in question is a Magnetool, from Hazel Park, MI. I think you have been told a wives tale. Wes |
#3
Posted to rec.crafts.metalworking
|
|||
|
|||
Anyone want a decent but big Surface Grinder? So. Cal
On 2010-11-18, Wes wrote:
GeoLane at PTD dot NET GeoLane at PTD dot NET wrote: On Sun, 14 Nov 2010 17:30:09 -0800, Gunner Asch wrote: This one runs ok, but is dirty and nasty. The 6x18 magnetic chuck needs repair..a pin inside has come loose and it doesnt go fully into Engage position. Not a big deal I've got a fine pole magnetic chuck that doesn't work as well as I suspect it should - there are strong areas and weak areas. I"ve read various opinions on the web regarding whether it's safe to take them apart versus those which say they'll lose their magnetism and be ruined. How do you tell if the one you're working on will lose its magnetism if you open it? The chuck in question is a Magnetool, from Hazel Park, MI. I think you have been told a wives tale. Which type of wife -- old -- or young? :-) Actually, it does depend on the type of permanent magnet. Older magnetic materials will only retain a certain amount of magnetism if the field strength falls below a certain level, and disassembling it opens the magnetic circuit so you do lose the strength. It requires a special fixture to re-magnetize to the original level. However, modern rare-earth magnets seem to not have this problem -- at last at the field strength levels involved in magnetic chucks. So -- the older it is, the more likely that it will suffer from being disassembled. Now -- if the magnet and carrier remain in contact with the pole pieces, you probably won't hurt anything. But if you separate them (a major struggle with a good one), you will lose field strength -- unless they have started making them with the rare earth magnets. (The same applies to the dial indicator holders and to stepper motors too, FWIW. :-) Good Luck, DoN. -- Remove oil spill source from e-mail Email: | Voice (all times): (703) 938-4564 (too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html --- Black Holes are where God is dividing by zero --- |
#4
Posted to rec.crafts.metalworking
|
|||
|
|||
Anyone want a decent but big Surface Grinder? So. Cal
So -- the older it is, the more likely that it will suffer from being disassembled. Now -- if the magnet and carrier remain in contact with the pole pieces, you probably won't hurt anything. But if you separate them (a major struggle with a good one), you will lose field strength -- unless they have started making them with the rare earth magnets. (The same applies to the dial indicator holders and to stepper motors too, FWIW. :-) Good Luck, DoN. My guess is that the chuck is from the mid 60s since that's about the age of the surface grinder. I'm not entirely sure what you mean in your second paragraph. My hunch is that I should turn the chuck "on" and then try to disassemble it. That way the magnets will be attached or close to whatever should be keeping them magnetized. ......OR... Do you mean that you can open it in the "off" position, but just don't move the magnets off of whatever they're attached to in the bottom half of the magnetic chuck? RWL |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Suggestions for a decent shop bench grinder | Home Repair | |||
Decent 4.5" angle grinder | Metalworking | |||
need Surface Grinder help | Metalworking | |||
Conundrum? Decent benchtop surface grinder | Metalworking | |||
Surface Grinder | Metalworking |