Edge Finding

[geedavell]

You have a company name or tool name for those? I have MSC, Travers, Enco, KBC, and a few other catalogs, but I don't want to look thru all those...
.

Here they are. If you local, I'll sell you mine for 1/2 price.

http://www.nolansupply.com/bysubcategory.asp?subcategory=SPI+Magnetic+Edge+Finder&type=False&specs=True

[ROOS_HAPPENS]

Sorry to bring back this thread, but with this attention focused on edge finders, and since I've owned a Fisher Micro edge finder I bought back in the 70's which I've always liked, out of curiosity I ran a Google search on Fisher Machine, which I totally expected to be long since gone out of business due to the decades old influx of Asian machine tools into this country. It turns out that they're not only still around & made in Hawthorne, CA...but they've got attitude, too. This was a pleasant surprise! Good for them!

http://www.fishermachine.com/about.php

http://www.fishermachine.com/index.php?content=buyproducts&cat=3

[kcstott]

Sorry to bring back this thread, but with this attention focused on edge finders, and since I've owned a Fisher Micro edge finder I bought back in the 70's which I've always liked, out of curiosity I ran a Google search on Fisher Machine, which I totally expected to be long since gone out of business due to the decades old influx of Asian machine tools into this country. It turns out that they're not only still around & made in Hawthorne, CA...but they've got attitude, too. This was a pleasant surprise! Good for them!

http://www.fishermachine.com/about.php

http://www.fishermachine.com/index.p...products&cat=3

I forgot all about those guys good to see they are still around unlike JFK tooling

[krwada]

Sorry to bring back this thread, but with this attention focused on edge finders, and since I've owned a Fisher Micro edge finder I bought back in the 70's which I've always liked, out of curiosity I ran a Google search on Fisher Machine, which I totally expected to be long since gone out of business due to the decades old influx of Asian machine tools into this country. It turns out that they're not only still around & made in Hawthorne, CA...but they've got attitude, too. This was a pleasant surprise! Good for them!

http://www.fishermachine.com/about.php

http://www.fishermachine.com/index.p...products&cat=3

I did not know about Fisher Machine.

Thanks!
Ken

[krwada]

The Story so far + overview

OK ... I just did a bunch of measurements just like KC said to do.

1. The mill is indeed trammed to < 0.001" over 6"
2. I checked the Z axis with a test indicator, and this thing is < 0.0005" over 4"
3. I checked a dial indicator against the Y axis DROS and found a 0.001" hysteresis.

So ... I decided to do one more thing. I decided to machine a test part and check this against the edge finder and DROS. Basically, the test is as follows:

1. Find the edge.
2. Locate to 0.400" from the edge
3. Mill a slot using 0.250" bit
4. Take careful measurements from the centerline of the slot to the edge
5. Do this in both directions.

Here is a picture of the result in both the Y and X axis:

As you can see, there is a 0.002" hysteresis in the Y axis and the X axis is "dead nuts on"


Actually, having a 0.001" offset is not much of a problem given the kind of work I expect to do with this thing. I know the hysteresis of the DROS vs. the test indicator itself is 0.001"

So, for a little background so all of you can see what I am referring to. Instead of hand-drilling a bunch of holes and tapping them and 'jiggling' and filing them to fit. I carefully measured, (as best I could), everything, and designed a bunch of fixtures to mount the DROS to the machine.

Here is a pic of the Y axis DROS with the cover off and exposed:


Here is a pic of the Y axis DROS with the swarf cover on:


Here is a pic of the X axis DROS with the swarf cover off and exposed:


Here is a pic of the X axis DROS with the (yes, it is carbon composite material I layed up myself), swarf cover on


Here is a front view of the mill with the readouts attached and the LED work lights turned on.


...

Now, I feel pretty confident (if I take care) that I can machine the parts I need. Also; these measurements and experiments have shown me that the OLD ways still work.

The OLD ways I was taught.

1. Measure and layout everything before the 1st cut
2. Make travel and cuts ALWAYS in the same direction
3. Tighten as much as possible, everything before making the cut
4. Make the 1st cut a reference cut, or make the 1st hole a reference hole
5. After #5, measure in place and move the machine to get the rest.

I can tell you this ... doing #4 then iterating #5 is very tedious work. It is really the only way I know of that will get the thing dialed in ... at least this is the way I know it.

Oh ... there is one more thing ... If one runs into a problem ... then designing and building a fixture may be the only way to solve it!

Thanks to all of you for helping me out.

Also; many thanks to KC for making the suggestions and helping me get back on track with getting confidence in operating the mill.

Confidence matters ... It matters a lot!

Ken

[VictorFranko]

Too much reading, sorry if someone already offered this advice.

ALWAYS indicate a vice under pressure. The bolts holding the solid jaw may not be tight. Put a parallel or 1-2-3 block in the vice and tighten BEFORE indicting or edge finding, always.
Also, the difference in your reading could be backlash in the lead screw, if you edge found going one direction and then came in with the edge finder the other direction, you'll almost always get a different reading.

Like I said, sorry if that was already covered.

[kcstott]

Too much reading, sorry if someone already offered this advice.

ALWAYS indicate a vice under pressure. The bolts holding the solid jaw may not be tight. Put a parallel or 1-2-3 block in the vice and tighten BEFORE indicting or edge finding, always.
Also, the difference in your reading could be backlash in the lead screw, if you edge found going one direction and then came in with the edge finder the other direction, you'll almost always get a different reading.

Like I said, sorry if that was already covered.

Vic I have to disagree. If your solid jaw is loose not only will you not be able to indicate the vise correctly you will not be able to machine a part square either.

The solid jaw should be clean and all sharp corners on the mating surface broke with a stone, wiped clean, lightly oiled, bolted down and properly torqued.

Also once every few years the vise should be resurfaced and squared on the grinder.

[ar15barrels]

Sorry to bring back this thread, but with this attention focused on edge finders, and since I've owned a Fisher Micro edge finder I bought back in the 70's which I've always liked, out of curiosity I ran a Google search on Fisher Machine, which I totally expected to be long since gone out of business due to the decades old influx of Asian machine tools into this country. It turns out that they're not only still around & made in Hawthorne, CA...but they've got attitude, too. This was a pleasant surprise! Good for them!

http://www.fishermachine.com/about.php

http://www.fishermachine.com/index.p...products&cat=3

Every shop I have been in has a set of their thread gauge wires.

[VictorFranko]

Vic I have to disagree. If your solid jaw is loose not only will you not be able to indicate the vise correctly you will not be able to machine a part square either.

The solid jaw should be clean and all sharp corners on the mating surface broke with a stone, wiped clean, lightly oiled, bolted down and properly torqued.

Also once every few years the vise should be resurfaced and squared on the grinder.

Actually, KC, if it happens to be loose and you indicate it under pressure, it will align the same under pressure with a part in the vise, generally speaking.
Of course, it should not be loose, but I've seen it, especially with what we affectionately call a Kimchi vise (Korean copy of a Kurt Anglock)
Not in every company, especially the larger ones, like back in the day when I worked at Lockheed, do you have the liberty or time to remove the vise and check everything out when you were moved over to an unfamiliar machine for the day.
I always defer to you on this site when it comes to machining, and you are great to share so much of your knowledge with the noobs, but in 36 years in the trade, I've learned a few thing too.
Indicating a vise under pressure is just good shop practice. You only use a vise with the solid jaw under pressure, why in the world would you indicate it any other way?

[krwada]

Properly torqued

Vic I have to disagree. If your solid jaw is loose not only will you not be able to indicate the vise correctly you will not be able to machine a part square either.

The solid jaw should be clean and all sharp corners on the mating surface broke with a stone, wiped clean, lightly oiled, bolted down and properly torqued.

Also once every few years the vise should be resurfaced and squared on the grinder.

Anyhow ... What do you mean by properly torqued? Should I have gotten a torque wrench to make sure the vice jaw is properly torqued?

I will also get a stone, and break the corners as you suggest.

[krwada]

Indicating a vise

Too much reading, sorry if someone already offered this advice.

ALWAYS indicate a vice under pressure. The bolts holding the solid jaw may not be tight. Put a parallel or 1-2-3 block in the vice and tighten BEFORE indicting or edge finding, always.
Also, the difference in your reading could be backlash in the lead screw, if you edge found going one direction and then came in with the edge finder the other direction, you'll almost always get a different reading.

Like I said, sorry if that was already covered.

When I did my initial test. The vice jaws were open. Then I indicated that surface. Then, I closed the vice jaws on a parallel... Then I indicated that too.

What you mention actually confirms the result I am getting with the machining test!

I will have to figure out another way to do a similar test.

Thanks!
Ken

[kcstott]

The fixed jaw has bolts on the bottom of the vise the should have a good torque on them 80ftlbs or so.
Vic I hear you, and agree but I'm more concerned with the jaw tilting. That would be bad.

[VictorFranko]

The fixed jaw has bolts on the bottom of the vise the should have a good torque on them 80ftlbs or so.
Vic I hear you, and agree but I'm more concerned with the jaw tilting. That would be bad.

Yes, the technical term for a loose solid jaw is "bad", LOL.

[krwada]

Jaw tilting

Yes, the technical term for a loose solid jaw is "bad", LOL.

Yes, this is not so good. I will try and figure out how much 'tilting' there is on the 'masala' vice.

I must admit, I did purchase a cheap knock off for the vice.

[VictorFranko]

Yes, this is not so good. I will try and figure out how much 'tilting' there is on the 'masala' vice.

I must admit, I did purchase a cheap knock off for the vice.

Don't discount "knock-off" vises, many are just fine, especially for home, non-production work.

KC probably already covered it, but in case he didn't, just put the vise under pressure using 1-2-3 blocks or a couple matched parallels, leaving yourself some room to run your indicator up and down across the face of the jaw vise.
Touch off at the top of the jaw and set your indicator to zero, and either lower the quill (or raise the table) until the indicator tip nears the bottom of the vise jaw. If it doesn't still read zero, there is a problem someplace in the equipment or the set up.

BTW, KC's great, isn't he?
I have not seen anyone offer as much quality advice or take as much time as he does to help fellow Calgunners.