Thread: What is this thing used for?

At the clearing sale where i bought my surface grinder, i also picked up this thing- I thought I had got the greatest bargain ever on a spare mag chuck but when I took it out of the wooden box I discovered it isn't a mag chuck at all. Can anyone tell me what it's used for? Obviously used in conjunction with a magnetic chuck, it appears to re-align the fields longitudinally, but to what purpose?
mag adapter plate 1.jpgmag adapter 2.jpg

G/day Pete, is it a transfer block?
Does it fit neatly on your mag chuck and extend the length of work holding?

cheers, shed

That would make sense, increasing the effective length of a mag chuck. I think it's actually the same length as my chuck though. I'll have to check that out.

Check whether the strip patterns on the top are the same direction as the bottom too. For stability purposes, sometimes it is better to turn the magnetic field around 90 degrees.

Michael

I put this adaptor plate on my mag chuck and and had a bit of a fiddle with it this arvo. Yes it definitely turns the field 90 degrees but under what sort of circumstances would this be desirable? Also when I put it on my chuck and activate the chuck, there is a much weaker magnetic force on top of the plate. I suspect this may be because the poles of my mag chuck are much narrower than the ones on the bottom of the plate- it's probably made to suit a chuck with wider poles.
I also tried extending it past the end of the chuck to see if it would conduct the field beyond the chuck- it didn't seem to do this, there was no grip on the cantilevered part. So I assume it's purpose is just to re-align the fields but I'm still in the dark as to why that is a thing.
Middle photo shows the underside.

I haven't got one so I haven't got first hand experience with them, but swapping the field around is done for long thin (around a pole width) parts, where you need to grind them in a particular direction - maybe there are lugs in the way for example. If you had one of these parts on a normal chuck, the part may not adhere well and be flicked off. By turning the field 90 degrees, the mag field has a better hold on the parts. See this post from here on... //metalworkforums.com/f65/t1601...64#post1563564

Michael

PS. Transfer blocks lose strength when there is an air gap. If the top of your chuck is dished even slightly, it will not work as well. The photos may be deceptive but it looks like there could be a gap.