Miller Falls No. 97 Breast Drill Refurbishment Help

[Brandon Burns]

I'm attempting to restore a nice working Miller Falls No. 97 Breast Drill. However I can't for the life of me figure out how to remove the gearing and main shaft from the main body. All searches have been dead ends. Anyone have an idea on how to get the shaft out and the gears? The threaded cap on the end appears to capture some ball bearings. It turns, but I'm starting to run into some resistance and don't want to break anything. Any help would be appreciated.


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[David M Anderson]

Have you tried soaking the shaft in "Blast" or WD40.
And then using compress air to blow out the area, then repeat again if needed.
Those bearing are loose and not in a casing so to speak...they can go everywhere.
Restoring a Stanley 905 right now, cleaning out the crud and old lubricate may just solve the problem.

https://www.youtube.com/watch?v=r5vZzH9w38g

[Stew Denton]

Hi Brandon,

I should have replied sooner, but didn't so my apology on that. What can happen with the threaded cap is that small amounts of rust and crud can build up in the treads, and when you try to turn it the junk can be pushed forward until it builds up in one spot into a little lump of solids, and then wants to cause the threads to bind. I am not saying that such has happened for sure in this case, but it can be the cause of the problem you are seeing. When this happens you can sometimes back the cap back down, but not any further out. One way to try to fix it is to soak it in a hydrocarbon fluid that can seep in and slowly help loosen and soften things up.

This problem can also especially occur if the tool has been oiled over the years, and then sets until most of the oil is gone, but the remaining small amount of oil helps bind the crud and rust together to make a hard little mass that binds things up.

One thing to try, to attack this mass, is to soak it in a solvent that will seep into the hard mass and help break it up by leaching out the oil or grease and also by softening up the rust. A good choice is something like a Diesel, mineral spirits or something like that can also be used, but Diesel will work better. Let it soak a day or a couple and then slowly try to work the cap in and out repeatedly. SOMETIMES the hard little mass can be broken up by slowly, with very little force, working the cap up and down the treads over and over. Don't run the cap in and out to the point that it almost binds up, work it back and forth gently. This can grind up the softened rust particles and slowly break up the hard little masses. Sometimes adding a little oil and trying to work it down into the active area will also help, after you finish soaking it and after you have worked it back and forth some.

Diesel will be a better softening agent than will be mineral spirits, because it has higher aromatics (please don't ask) content than does mineral spirits, and of the normal hydrocarbon classes, aromatic compounds have the highest solvency properties.

The oil that you add can be soaked out of the joint by soaking it in paint thinner (not lacquer thinner) if the oil doesn't seem to help and you want to try something else, but first want to clean out the oil. Soak it in the paint thinner, let it drain thoroughly, soak again, let it drain, and do this a few times, then let the paint thinner dry, and most of the oil should out of the threads. Paint thinner is better than gasoline or Diesel for this, because it has a lower viscosity than heavier stuff like Diesel, but it's solvency properties are not quite as good, but they should be plenty good enough. It also evaporates much more quickly than Diesel or gasoline, because it has a much narrower and lower temperature distillation range than the highest boiling components of the other two materials.

What ever you do, don't get in a hurry, as my dad used to say "don't get in a big toot", let the solvent have time to do it's job and go easy at trying to break up the rust and crud (if in fact that is the problem.)

Stew