Drawbar "tightness" and cleaning question

[seal killer]

All--

How much do you tighten the drawbar when drawing a collet or other tool holder up into the spindle? Snug with a wrench? Tight with a wrench?

I will be in the process of cleaning the cosmoline (or whatever it is) off my mill for a while. I plan to use Birchwood Casey's Degreaser simply because I use it a lot in my gun shop and it works so well. Comments?

--Bill

[Capt Turk]

I just snug the drawbar, and a touch. Only had a mill holder move once in over a year.

I use WD-40 to clean up machinery. I don't like the idea of using a degreaser. There's always a chance of leaving some area bare of oil. I have enough problems with surfaces trying to rust. I keep all surfaces fairly dripping with oil. Still have rust problems some times.

My shop is a 12'x12' tin shed with no insulation.

[RET]

Captain, even in Florida, if you insulate your shop, it will probably help your condensation problems. What you want to do is to minimise the tempearature swings.

Another possibility is to do what I believe Jim Glass suggested in a previous thread. Fasten a low wattage heater to the lathe bed or mill column (the large heavy components) and leave it on all the time. This would mean the machine was slightly warmer than its surroundings and should reduce the condensation by quite a lot.

I think either of those would be worth trying.

Richard Trounce.

[RET]

As far as the drawbar question is concerned, on the Bridgeport, I use a box end wrench and the spindle brake to tighten the drawbar up solid.

Remember, the "key" in the spindle is just the end of a screw, the last thing you want is for the collet (or whatever other adapter you are using) to move. It will shear the end of the screw off very easily. The spindle is designed to stand up to that treatment. If you are trying to overtighten, the spindle brake will slip.

Richard Trounce.

[SteveM]

I was milling in the lathe and the handwheel collet closer is not enough to tighten an endmill. My rotary table has the marks to prove it

I have a wrench for the Pratt & Whtney and snug them down pretty good. Have not had a collet move that I could tell.

Steve

[GadgetBuilder]

Required drawbar tightness depends on the type of spindle.

My mill has an MT3 spindle so it doesn't take much torque on the drawbar to lock an endmill holder solidly in place. MT3 isn't self-releasing because the taper angle is shallow.

OTOH, R8 is self-releasing so an R8 spindle needs more torque on the drawbar to ensure a solid lock.

John

[BadDog]

Man, I wish they would fix the errors so folks dont keep posting 4 or 5 times.

On the R8 draw bar, with a proper fitting shaft in the collet, you can feel it get tight. It's going very smoothly and easily. Then you start feeling resistance. Then all of a sudden, it's like you hit a wall and it gets "solid". That's the point where you've taken up the spring and space. For a smaller cutter, like 1/4" or so, I just pull sollidly against that resistance and go. For a 1/2 rougher I'm going to burry, I grab the brake firmly and give it one more moderate heave. On that, you'll feel it hit another wall where the torque required to go further spikes way up again. That's done. I once (and I do mean ONCE) forgot to lock the knee while roughing on some tough steel. It actually picked up the table and knee, scrapping the part! But the EM didn't move...

[Jose Rivera]

Hey sealkiller, took the plunge ?

Congrats !!
Let us know how it goes.

I am still in the "I have to buy a mill" stages and have not made a decision (nor have the money) yet.

Agree with Capt Turk, snug is all you need to tighten the collets.

As for cleaning that messy grease that they put on machinery I used some left over Colman stove fluid I had and it worked better that most other solvents I used (cleaning a Grizzly G4000 lathe).
I have also used BBQ lighter fluid. All are flammable of course.

As for WD-40, most people think that is a lubricant but all it is what Capt use it for, a solvent that quickly will evaporate. I use it as a cutting oil for aluminum instead of kerosene, but Kerosene works very well at keeping aluminum from gumming up on the tool. Specially while parting-off material.

[tornitore45]

I am not convinced that R8 are selfreleasing. From a limited experience on my X3 mill, I snug the R8 EM Holder just barely and it always take a good wack with the mallet to release.

As for collets holding power, R8 collets do not hold the EM wery well, I use them only for the spotting drill; small EM with light passes and if I really need an extra inch of Z axes.
To rough safely use a EM holder and pull the EM out against the screw before tightening the set screw.