# Facing tool keeps leaving .0005 to .001 lines down the part.



## turningwheels (Jun 3, 2020)

It's hard to explain, but when using my 2" facing tool on a 3.5 inch part, when doing the overlap, I get a distinct ridge that is about a thou in difference. even though that area is in the "overlap" there really shouldn't be any ridges. Tool marks yes, I get that. I did run the tool down one side and up the other, rather than bringing the tool back to the same side as the original cut.
The facing tool is this guy. https://www.amazon.com/gp/product/B00HQMXSM2/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1
Any suggestions on how to troubleshoot is greatly appreciated. Thanks.


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## mmcmdl (Jun 3, 2020)

Your head may be a bit out . Have you trammed it lately ?


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## Ulma Doctor (Jun 3, 2020)

put an indicator in a collet or otherwise attach it to the spindle and run the table under the dial indicator
any fluctuation of the table will show up on the indicator


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## turningwheels (Jun 3, 2020)

The X Axis is less than a thousand across the whole board. the y axis is just under a thousand across 5 .5 inches. So it's hard to see why in 2 inches I would see such a big difference.


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## darkzero (Jun 3, 2020)

The larger the diameter cutter & wider step over, the more noticeable it will be. You have to check tram. It sounds like you just moved the table around with an indicator stationary in the spindle? If yes that won't tell you anything in regards to your issue.

Assuming you had the part mounted in your vise in the orientation seen in the pic, ie that line parallel with the slots on your table & you were using the X-axis to make your cuts. You need to check nod (inline with the Y-axis). Mount an indicator in the spindle & sweep the front edge of the table to the back edge of the table (turning the spindle by hand).


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## turningwheels (Jun 4, 2020)

Yep, the part is mounted in line with the X-axis. Dumb question coming, but if the table has a vise and t-nut slots how the heck to I sweep without hitting every bump in the way?


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## darkzero (Jun 4, 2020)

When you sweep, as you get to a slot, pull the plunger back or needle up (depending on what kind of indicator you are using) to clear the slot, then let it back down carefully. As long as your indicator holder setup is rigid it shouldn't throw the reading off.

Or if you have two 123 blocks that you trust to be matched, you can place those on the table & indicate off those, no need to worry about the slots.

If using a dial indicator instead of a dial test indicator, if you have a button head indicator point, that can help with the slots also.


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## turningwheels (Jun 4, 2020)

In my very unscientific testing, I clamped a parallel to the table, attached a Dial Indicator to the head and ran the y axis front to back. Out less than half a thou.
then I installed the drill chuck and mounted the Dial Indicator in that and ran it in a circle about 3 inches in diameter, picking up the shaft at each rail and placing it gently on the next one. Less than half a thou. Grabbing the spindle and pushing and pulling on it I can make it move about 3-5 thousand. same with the column.
I am wondering if it's the tool? Could the inserts be not seated in line with each other? Would that create the line down part on the X axis? It sucks to not know how to troubleshoot these little issues. Now I know why machinists charge so much. The setup and prep takes forever!


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## turningwheels (Jun 4, 2020)

darkzero said:


> When you sweep, as you get to a slot, pull the plunger back or needle up (depending on what kind of indicator you are using) to clear the slot, then let it back down carefully. As long as your indicator holder setup is rigid it shouldn't throw the reading off.
> 
> Or if you have two 123 blocks that you trust to be matched, you can place those on the table & indicate off those, no need to worry about the slots.
> 
> If using a dial indicator instead of a dial test indicator, if you have a button head indicator point, that can help with the slots also.


I have both a .0005 DTI and a .001 Dial indicator. Using the Dial Indicator on this one in the manner you have described.


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## darkzero (Jun 4, 2020)

Yes it can be from a number of various factors. Anything from locking the quill, loose gibs on the table and/or knee/column (not sure what kind of mill you have). Can also be from just lack of rigidity. Checking tram on the head is a good first start. Again, due to the diameter of the cutter, however much your tram is out, it will amplify that the bigger the cutter.

Try cutting with smaller step overs or a smaller cutter, if your tram is not way off, chances are the lines you feel will improve. Lock every axis that doesn't need to move when cutting.


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## mmcmdl (Jun 4, 2020)

Take the vise off the table and tram the entire width of the bed . Get it as close as possible . BP's have approx a 9 " bed width . If you get it to within .0005 you shouldn't have much of a mismatch with a 2 inch cutter .  In other words , make a larger diameter sweep if this makes sense .


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## turningwheels (Jun 4, 2020)

Yep it does make sense. Now to figure out how to tram my mill. Is that usually done with the gibs on the vertical column? Sorry for all the n00b questions but this is all new to me and super fun too!


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## mickri (Jun 4, 2020)

There are several threads on tramming a mill. Video's online too.  The exact technique depends on the type of mill you have.  Tell us what mill you have and you will get suggestions on the different ways to tram your mill.


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## jmkasunich (Jun 4, 2020)

turningwheels said:


> Yep it does make sense. Now to figure out how to tram my mill. Is that usually done with the gibs on the vertical column? Sorry for all the n00b questions but this is all new to me and super fun too!


You really need to tell us what kind of a mill you have.  Several people in the thread (including me) assumed that you had a bridgeport (or clone) where the head both tilts side-to-side and nods front-to-back.  So it is easy to get out of tram (and almost as easy to tram it back in).  If your mill head is not intended to tilt, then any tilt you have will be harder to remove.  Show us your mill!


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## turningwheels (Jun 4, 2020)

Thank you guys, I really appreciate your help and suggestions! I have a Grizzly G0619. https://www.grizzly.com/products/Grizzly-6-x-21-1-HP-Mill-Drill/G0619. Brand new about a month old. I would love to know how tram this thing. You know, tell it to quit nodding at me in that creepy way...
FYI, when I got the Facing tool, it worked beautifully with multiple passes and no discernible deviations besides tool marks. smooth as glass.


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## jwmelvin (Jun 6, 2020)

I don’t think that was the issue. The website doesn’t show how the column attaches to the base. Can you post a picture of that connection?


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## higgite (Jun 6, 2020)

jwmelvin said:


> I don’t think that was the issue. The website doesn’t show how the column attaches to the base. Can you post a picture of that connection?


The column is bolted to the top of the base. See pics on pages 22, 29, 32 and 34.


			https://cdn0.grizzly.com/manuals/g0619_m.pdf
		


Tom


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## jwmelvin (Jun 6, 2020)

That pic on p32 does the trick. Fairly typical, from what I gather. Most common approach is to shim under the base at the bolts. Better is to shim or install jacking screws from the top side at each bolt (effectively an adjustable shim) and then, once trammed, inject epoxy into the gap so that the shims aren’t the only points of contact.


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## turningwheels (Jun 6, 2020)

So I did a very unscientific (nod test?). Basically measuring from z axis on the front side up and down this piece that is about as square as I can get. I couldn't get it clamped down though, hence the unscientific results. I saw a .0015 movement in 5 inches. Going along the X axis, I saw a .0005 graduation along the whole table. So Once I can figure out how to clamp my piece down, I am not convinced it is out of total whack.








						New photo by Sam “Mad About Moto” Lambie
					






					photos.app.goo.gl


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## GunsOfNavarone (Jun 6, 2020)

Man, I tell you as being a newb myself, edge technologies tramming tool made it SO MUCH EASIER. Worth every penny.
Tram tool


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## turningwheels (Jun 8, 2020)

Ok this image is using my facing tool from right to left on the x axis.I measured the thickness of this piece where the measurements are written.  As you can see, it appears to me that the front of the mill is sagging just a bit  .0015 if my math is correct.  So that means I should be shimming the toe (closest to operator) about a thousandth? My guess would be a little more to compensate for the weight of the head and column.  Does this seem correct? Or is it something else that I am missing?


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## RJSakowski (Jun 8, 2020)

Leaving a ridge parallel to the direction of cut when facing can only be due to one thing.  The spindle axis is not perpendicular to the ways that are perpendicular to the direction of cut.  It is typically assumed that tramming the spindle to the table is equivalent to tramming to the ways and that is not necessarily true.  

A sweep of the table in x and y directions with a DTI can reveal a non parallel condition although one has to be aware of extenuating conditions such as loose gibs, e.g. When the table is moved to an extreme condition, the center of gravity can be over an unsupported region and the table can tilt. Here is a graph showing this tilt and the improvement when the gibs are adjusted.



The method that I use to tram the spindle is to clamp a piece of plate to the the table and mill a circular path equal in diameter to the path of tramming tool.using a small diameter end mill.  The path by default will be parallel to the x and y ways.   For a manual mill, four elevated bosses  at the + and - extents in x any y can be created.  These surfaces will be the tramming points.

In the case of your mill, a non trammed condition in the y direction can be caused by several factors.  The spindle may not be parallel to the z axis ways.  The z axis gib can be too loose, causing the head to droop slightly.  The quill may have excessive play causing sag.  The mill column may not be perpendicular to the y axis ways.  Your axes can be locked down which will eliminate any tilt due to loose gibs.  You can also lock the quill which will effectively eliminate play.

A simple check for tram is to face in both directions.  A properly trammed spindle will have a similar cut pattern .  If you have cross hatching in one direction but not the other, you have an out of tram condition.  Small mills will experience deflection due to cutting force which will raise the trailing side of the facing tool, causing the arcs to be be facing the same way.  If the out of tram condition equals or exceeds the cutting force deflection, the back side of the tool contacts the surface resulting in a cross hatch pattern.  Depending on the depth of cut and rigidity of the machine, a very light cut or second pass on a well trammed machine can still yield a cross hatch pattern.


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## turningwheels (Jun 8, 2020)

Whoa. That was a lot to digest.  Thank you very much for the info! I think that I got the gist of it all. But what I think is the ultimate culprit is the vise! After tramming the crap out of the table with a .001 shim till I got about .0005 or better across the y axis. Then I added the vise and everything went out the window. I trammed the vise only to see a .0035 swing over a few inches on the vise.  Gah. Not sure how to fix this issue, but to call grizzly and see what they will do about that. unless you guys have a suggestion.


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## turningwheels (Jun 8, 2020)

Any machinists in Taos, NM that are willing to come over and help me adjust this puppy? I know that I can get it dialed in, but when one is flailing by oneself, you can't really learn how to flail differently.


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