Squaring a milling vise

That's gotta be a _short_ book, wot?

It's longer than it should have been, he's French and couldn't resist rambling on about fear and bravery. But it does explain ancient infantry and cavalry tactics quite well, enough to make Xenophon easier to follow;

Harold, indicating the table isn't a waste on a mill-drill. On the one I bought the tee slots were on a slight angle to the ways. I made accurate keys for the vise by fitting the keys snugly into the slots and then milling a step on both top edges that was automatically parallel to table travel.

Jim Wilkins

or search of part # SG891-5414, on sale for $35.99

Page 345 of the master catalog has a collection of them for different sized spindle noses.

Doug White

Jim Wilkins

I agree with your process, Jim. If the T slots are not parallel to table travel, that makes sense. However, I think you got the wrong impression of my comment, or I flat missed what was said. Certainly could be the case.

What is a waste of time is running the table side to side with an indicator in contact with the table surface. It doesn't determine head orientation, it simply displays error in tracking of the table, which may be caused by improper machining of the surface, or perhaps sagging of the casting. I got the impression his intended purpose was to square the spindle with the table surface, and that, of course, can not be accomplished by what I stated. .

The vise, of course, would be properly oriented by this function, where it passes the fixed indicator as the table is moved side to side. The purpose is to establish a parallel plane between the travel of the table and the vise fixed jaw.

Harold

I lock the spindle, and make sure that the way everything is aligned, the slight rocking of the spindle will not seriously affect the measurement. So, the indicator is as perpendicular to the vise jaw as I can get it. Rocking the spindle should cause only the slightest movement of the reading. Then, I run the vise back and forth several times until I get it square. I recheck after final tightening of the vise bolts to make sure it didn't shift or more likely distort from the bolting force.

If you aligned the vise by moving the X axis, maybe the X and Y are not orthogonal (Hope this isn't the case!)

Jon

It has a C-shaped piece that wraps around the spindle nose and a screw that secures it to the spindle. It has a 3-piece articulated arm that holds the indicator. These generally only fit machines that have a spindle nose very close to the same as a Bridgeport 1J or 2J head. You need a spindle lock to keep the spindle from turning very much. If you align the indicator feeler right, this slight rocking will have far less than .001" effect on the reading. You can check that this is true by just rocking the spindle by hand. If the reading doesn't change, then you have the feeler pointed right at the vise jaw. Some vise jaws are not quite straight, so you check both ends and ignore the middle reading.

Jon

Yup, I bought one of those boat anchors, too. I used the swivel one time, was APPALLED at the flexibility of the whole stack, pulled the vise off the swivel base and have never used it again. It is actually EASIER to align the vise without the swivel, you loosen only ONE bolt and tap the vise a little to adjust the end the indicator is reading, then run down to the other end.

That is a problem. How to you change the tool with the drawbar?

Jon

I did not.

I did not. It was clamped parallel to the Y-axis by the long sides.

That's what I did.

I can see that. However, now that I got the vise sorted, I do not *dare* to change anything :-) If I have to take it off I will certainly consider ridding myself of the base.

Very...:-)

I sense one coming around the 24th of December. As I mentioned elsewhere, I cannot see how one can make measurments to 1/1000" if the random zero error is about 3-4/1000". This has to be addressed.

As I mentioned elsewhere, I suspect that is coming. Right now I am so pleased that everything is square I do not want to disturb anything. The family has to walk around the machine on tippy toes and speak softly in its presence.

There is a hole at the top which accepts a tommy bar of sorts. This stops the spindle rotating and the drawbar can be unscrewed. To change just the bit I have two collet keys - one holds the top of the spindle steady and the other one does the business.

The spindle does not lock, that is one of the problems. But I solved that now.

Now you are frightening me! I did basically what you did but it never occured to me to check that the X and Y are orthogonal. Job for tomorrow...

Locking a BP spindle doesn't eliminate motion. You have the slop of the plastic keys that will permit minimal spindle rotation, albeit very little. Any is too much if you rely on the spindle to be locked dead. It is for that reason I suggested that a setup is suspect if motion of any kind is a problem. An indictor held at the right attitude in a drill chuck with the spindle free will serve perfectly well. You just have to use good judgment when making the setup. That incudes using an indicator that is sensitive.

Harold

Just out of curiousity, I wonder if the indicator error occurs every time the pointer goes a full turn?

Dial indicator's pointers typically rest past zero, but if you don't need to indicate the full range of the indicator (1 inch or 1000 x .001"), you can start the measurement at any spot on the plunger travel.

You shouldn't have to (the one you have is messed up), but it might give better/more consistent results if you use a different area of the plunger travel.

If this dial indicator can't be returned for a good replacement or refund, take it apart just for the experience of seeing the tiny internal parts, and also to eliminate any future frustrations of measurement errors.

Indeed. Marshal Foch was an interesting charector. He managed to get about 6 million young Frenchmen killed.

ROFLMAO

Its been raining for a week here, the back 40 is either under standing water, or has 4" of mud on it, so it limits my ability to do some stuff...Im trying to clean up the shop today...sigh...

Gunner

"They couldn't hit an elephant at this dist..." Maj. Gen. John Sedgewick, killed by a sniper in 1864 at the battle of Spotsylvania

Hiram Maxim changed the face of war forever, as did Herr Krupp.

Gunner

"They couldn't hit an elephant at this dist..." Maj. Gen. John Sedgewick, killed by a sniper in 1864 at the battle of Spotsylvania

On Fri, 28 Nov 2008 10:02:27 -0800, the infamous Gunner Asch scrawled the following:

Um, OUCH! C'est la guerre, non?

We've had fog and thick overcast/40F temps daily for a couple weeks now. I'd almost welcome rain and intermittent sun for awhile.

-- In all affairs it's a healthy thing now and then to hang a question mark on the things you have long taken for granted. -- Bertrand Russell

On Fri, 28 Nov 2008 13:22:11 -0800, the infamous Gunner Asch scrawled the following:

Respectively, they gave us the new/improved gatling gun and the coffemaker, right?

-- In all affairs it's a healthy thing now and then to hang a question mark on the things you have long taken for granted. -- Bertrand Russell

You are right. I fiddled until I found a point where the zero was more or less consistent and did the set up there. I think it was Jim Wilkins that led me to formulate the policy "the cheaper the tool, the more expensive the measuring equipment needs to be".

Ayup. WW1, was the last war fought with 18th and 19th century battle tactics such as the mass charge towards the other fellows lines

Unfortunately a large percentage of the Generals attended St. Cyre and other bastions of military science that hadnt got the word that they were facing a new age.

The saying is that "we are always fighting the last war" has a great deal of truth to it. We develope tactics and methods during the war we are in, and pass em along. The next war of course is completely different and they start fighting it with the tactics from the last war.

Shrug..thats why Herr Shicklegrubbers Blitzkrieg was so effective. Surprise and lightening speed. And the end run around te Maginot Line..a marvelous bit of engineering that was suitible for 1917, but became a death trap in 1940.

The current war in the Sandbox...we had some practice in 1991..but it was largely a replay of the Blitzkrieg. We didnt have to learn about asymetrical warfare..last time we had any of that was in Nam..and it was a jungle war for the most part. Hearts and minds and lighting up the jungle.

In the sand box..hearts and minds and lighting up minnows swimming amoung the schools of fish.

Shrug..we learn, and we learn well, but it takes us time..on the job training.

Gunner

"They couldn't hit an elephant at this dist..." Maj. Gen. John Sedgewick, killed by a sniper in 1864 at the battle of Spotsylvania

Or at least the less you can trust, the more you should check. I have a similar problem from the half century of wear on my old American iron.

Measuring practice says that the instrument should be 10 times better than the error being measured, in practice 2X is often enough. You can probably check a mill-drill well enough with an indicator graduated to

You may not be able to correct any errors you find but you will know what machining accuracy you can assume and where you have to take extra precautions. For instance that tilted quill didn't cause us any problems making R&D electronics parts. If we were reboring small engine cylinders we might have shimmed the column base.

My lathe and mill will hit 0.005" from the dials, then I measure and take light cuts. They aren't worn that badly, much of it is from the vise or chuck. If I am working on a newer mill with a DRO I can usually locate to 0.001" or better, such as making two separate jig parts that will fit together with dowel pins. At home I have to clamp both pieces together and ream through each hole, or use the tedious disk/button method.

Jim Wilkins

The Russians and Japanese in 1905 first figured out how to use machine guns in the attack. Before that they were seen as fixed artillery, but real artillery outranged and destroyed them.

The bloodiest British attack, the Somme, ended with a cavalry charge through and behind the German lines. The charge succeeded but the rest of the force was too weakened to take advantage of it.

You're right. I've worked at a think tank that tries to see ahead, and it's almost impossible to detect (or ADMIT) the weakness in your own methods that the enemy will find and exploit. You have to predict and cover all of them, they only need one. Before Pearl Harbor the Japanese dropped hints of attacks all over the Pacific, even in Peru, so we didn't know which ones were real. We suspected they would attack the Panama Canal locks with sub-launched aircraft and assumed Pearl was safe because it was too shallow for OUR air-dropped torpedos.

That was mainly due to Guderian, Rommel & co, both of whom had engineering as well as military training. The rest of the Wehrmacht marched on foot. Guderian was temporarily fired for advancing too fast, Rommel was lost to his own headquarters which stopped sending supplies. That speed record he set was in France, not the open desert. They both knew how to create and exploit confusion. Neither did very well against a properly organized defense, ie Tobruk.

If you plan for the most dangerous attacks, you buy time to adjust to the lesser ones. There was never a chance the VC or NVA could throw us out of Nam. We left only after reconciling with the real threat, China, which also gave up on Vietnam and fought (lost) a short war with them later.

JW