Dial indicator magnetic base hard to switch

[ericc]

Hi. I bought one of those ubiquitous dial indicator bases that look like the cheap Harbor Freight ones. It was inexpensive at a garage sale, so even though I usually avoid this stuff, I bought this one. It only lasted me a few uses before the knob became too hard to turn. This tool is not that old, but it seemed to be jammed tight. I saw a post around somewhere, but I cannot find it now, that said unscrew the center post and the hole will go all the way down to the magnet, and a small amount of oil can be dribbled in. This should free up the rotating magnet. I tried this, and it did not work. The magnet was as as tight as ever. It is tight enough so I am in danger of dislocating a finger if I try too hard to turn it. I peeled off that cheapo thin aluminum front, revealing a couple of screws. Removing the two screws allows removal of a bezel that holds the knob in. When the knob is removed, the innards are revealed. It is composed of a cylindrical core that is magnetized cross wise. The two pole pieces have rounded ends which turn in the circular bore, and are separated by a brass plate in the middle. Apparently, they have come loose from the brass plate and can become cocked, jamming them in the bore. The solution is obvious: extract the magnets, separate them from the central brass plate, and glue the assembly together so it doesn't bind. This thing is just so cheap and unreliable, and I regret even paying a couple of bucks for it. NOT SO FAST!!!! If you extract the magnets and separate them from the case, the risk is run of breaking the magnetic path and losing their magnetism. Many stories of woe appear on the Internet. Since the pieces are loose, special care must be taken not to allow them to become magnetically separated. So, has anybody had any luck fixing these things? There are two ideas that I have, but both of them are not real fixes. First, I can dial the base to the "on" setting and use it as a permanently on magnetic base. I can even duct tape the hole shut. The second way is to machine an aluminum knob and connect a huge handle which I can chuck an adjustable wrench or a big cheater bar to actuate the indicator. This is difficult, and may cause disturbance to fiddly set-ups. I have a Starrett base, which is obviously much older, and it is as smooth as butter. It feels high quality and impossible to jam. Still, I hate to throw things away if they can be fixed. Is there a clever fix like "tap from both sides simultaneously with a copper hammer" or some other silly thing to get this thing working again? Maybe they just aren't meant to be used.

 

[Ulma Doctor]

if you have nothing better to do, have a go at fixing it.
otherwise, bail on the bad one and pick an inexpensive one from shars or all industrial tool supply
even harbor freight has an inexpensive base they will return in the event of defect

 

[Tozguy]

Good subject, I have magnetic base that is very stiff to turn and it bothers me. If there is a fix it would be nice to know.
Maybe someone here has some tips for us.

 

[Buffalo21]

a couple of my cheaper magnetic bases, if you screw the shaft into the base too far, it interferes with the knob/switching mechanism. If I back the shaft out a turn or so, it works perfectly.

 

[cathead]

You can likely fix it. At least give it a try. Maybe a little epoxy would work for you to hold it together. Nothing ventured,
nothing gained as the saying goes. I don't think that you will lose any noticeable magnetism by working it over and
gluing it back together. If the surfaces are very flat, cyanoacrylate (crazy glue) might work as well. Be sure the surfaces
are cleaned with acetone or similar solvent for better "stickage", and maybe even using a little sandpaper might help too.

 

[ericc]

Ahhh. I found the post. Good old google:

How Do You Remagnitize A Switchable Mag Base?

I have an old switchable magnetic base that I would like to use. It has a little force but not as much as I would like (something near a neo-mag). Any body know who might do this?

www.hobby-machinist.com

I probably won't buy one from Shars. I think that I get disappointed more easily than average and end up tasting "the bitterness of poor quality" more acutely.

 

[mmcmdl]

I've got a few Starretts down the basement that held chip guards . They might be listed below . Can't remember .

 

[erikmannie]

I have a used US made one (I believe, it came from my Dad’s laboratory facility) that works fine that I can send you for free if you just pay the actual postage. Text Erik at (706)293-8973.

 

[ericc]

I have a used US made one (I believe, it came from my Dad’s laboratory facility) that works fine that I can send you for free if you just pay the actual postage. Text Erik at (706)293-8973.


Hi Erik. Thank you for your kind offer. I was just trying to find something to do during our shelter-in-place. I have a Starrett 657, and it is perfect. It is so smooth and nice. There is not a thing wrong about it except its price. But, paraphrasing John Ruskin, that has been long forgotten. I was just curious what was wrong with the silly cheap magnetic base.

 

[ericc]

I decided to make a wrench to turn the plug. Normally, I would make the wrench out of steel, but in this case, aluminum seemed more appropriate. This was made by welding together a piece of 1/4" aluminum plate and a piece of 1/4" aluminum angle. The weld has a few inclusions, but at least it wetted in and appears to be strong. A poor craftsman blames his tools, which I will readily do now .