# Help confirm my tram



## wildo (Mar 12, 2017)

Would anyone mind helping me with my tram? What is interesting to me is that when the indicator has a little side load, it seems to move a little in a way that I don't think is representative of the surface it's riding against. This is seen in the second part of the video when tramming the vise. When I move left, the indicator rides at around +.001 on the dial, and when I move right it rides around .000" on the dial. I don't know what this means.

When taking a dynamic measurement like this, do you "start" your observed reading after the part is moving, or am I actually seeing a change in measurement of the surface here? Also- given my measurements, would you consider this a decent enough tram?

Thanks!


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## mikey (Mar 12, 2017)

For general work, a thou over a 5" run should be okay but zero is better. I'm not sure how others do it but I normally run the table in the same way you're doing it and if I pick up a deviation, I move the vise away from the indicator, tap the vise into what I think is better alignment, then bring the indicator back and *re-zero *it. Then I make another pass to see if alignment is better. Rinse, repeat until vise is aligned as well as my machine will allow.


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## wildo (Mar 12, 2017)

Would it make more sense to hold some 1 2 3 blocks in the vise and then indicate off of them? This way I'm validating that the work itself as held square to the spindle.  Also, the blocks would give me a smoother surface for the indicator to ride against which might help me get a more accurate reading. Is my thinking correct on this?


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## mikey (Mar 12, 2017)

wildo said:


> Would it make more sense to hold some 1 2 3 blocks in the vise and then indicate off of them? This way I'm validating that the work itself as held square to the spindle.  Also, the blocks would give me a smoother surface for the indicator to ride against which might help me get a more accurate reading. Is my thinking correct on this?



If you have blocks or a parallel you trust, sure. I usually indicate against the jaw but on my Sherline vise, I use a B&S parallel. Works for me, anyway.


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## JimDawson (Mar 12, 2017)

wildo said:


> What is interesting to me is that when the indicator has a little side load, it seems to move a little in a way that I don't think is representative of the surface it's riding against.



It looks like the stylus is a bit loose in the pivot.  Maybe tighten it a bit, very carefully.



wildo said:


> When taking a dynamic measurement like this, do you "start" your observed reading after the part is moving, or am I actually seeing a change in measurement of the surface here?



Usually the dynamic reading is slightly different than the static reading.  But see above.  You could also could be seeing some anomaly in the surface.  



wildo said:


> Also- given my measurements, would you consider this a decent enough tram?



0.001 in 5 inches is not bad.  Plenty good for most work.


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## intjonmiller (Mar 12, 2017)

I don't have nearly as much experience as these other guys, but when I'm unsure about the reading I will gently manually retract the indicator tip and gently let it return to the reference surface a couple times. That seems to take out any side load that may have been introduced, and the reading I then get has been quite repeatable.


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## tweinke (Mar 12, 2017)

Just a thought from an expert by no means, gibs aren't loose are they?


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## wildo (Mar 13, 2017)

Thanks for all the thoughts, folks! Looks like I have a couple options to investigate here.


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## Bob Korves (Mar 13, 2017)

I prefer to measure things directly.  Putting a second part or tool in the stack tends to add whatever errors it has to the equation.  In my mind, if you want to measure or indicate something, do it on the part you are interested in, not on a surrogate, if that is possible.  If direct measuring is awkward or wonky, sometimes you have to add something else to get a good reading.


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## Wreck™Wreck (Mar 13, 2017)

If there is any play in the ways it will sometimes show up when changing directions, apply a small amount of pressure to the table locks and see what happens.


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## jamby (Mar 13, 2017)

I agree with the table ways argument.  I've run some really bad machines that will have much larger movement when the direction is changed.   I always moved the cutter from right to left on the finish cut so that's where I set my zero.
If your machine is new adjusting the gibs could be called for.   You can check by running the table to one end and setting an indicator then push/pull on the table and see how much the indicator moves.

Jim


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## wildo (Mar 13, 2017)

You guys were right. I just checked and I have .007" movement on the dial, at the vice (more/less center) when I try to tweak the table. Clearly the gibs aren't tight enough. I haven't addressed it yet, as I don't recall how to get to the x-axis gib and really am hoping I don't have to take the table off to do so.


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## Bob Korves (Mar 13, 2017)

wildo said:


> You guys were right. I just checked and I have .007" movement on the dial, at the vice (more/less center) when I try to tweak the table. Clearly the gibs aren't tight enough. I haven't addressed it yet, as I don't recall how to get to the x-axis gib and really am hoping I don't have to take the table off to do so.


Most of the wear generally takes place in the middle of the travel.  If you snug up the gib there, often times it will be too tight at the ends of the travel.  If you set the gib at the ends of the travel, it will be loose in the middle -- if you have that wear issue, which is fairly common.  You can set it loose to get the entire travel or tighten it up and then reset it if you need the entire table travel.  Wait a minute, I think I remember that you have a Millrite.  So do I.  On a Millrite you must remove the carriage and table to adjust the X axis gib.  Get it right while it is off...


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## wildo (Mar 13, 2017)

Bob Korves said:


> ]Wait a minute, I think I remember that you have a Millrite.  So do I.  On a Millrite you must remove the carriage and table to adjust the X axis gib.  Get it right while it is off...



Ugh. I just got this mill back together. How do you know if you have it right while the table is off? For that matter, could I tighten the Y gib super tight and then check if the movement is in the X? That seems like a reasonable thing to do first, right?


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## Bob Korves (Mar 13, 2017)

wildo said:


> Ugh. I just got this mill back together. How do you know if you have it right while the table is off? For that matter, could I tighten the Y gib super tight and then check if the movement is in the X? That seems like a reasonable thing to do first, right?


Yes, you can tighten up the Y and the Z to make sure everything except the X is tight and then test it.  Just using the X, Y and Z table and knee locks should be enough for testing, the gibs can be left alone.  You could also use the X and Z  locks to see if the Y is loose, same idea for the Z.


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## Wreck™Wreck (Mar 14, 2017)

wildo said:


> You guys were right. I just checked and I have .007" movement on the dial, at the vice (more/less center) when I try to tweak the table. Clearly the gibs aren't tight enough. I haven't addressed it yet, as I don't recall how to get to the x-axis gib and really am hoping I don't have to take the table off to do so.


You have just opened a large can of worms for yourself, if you tighten the gibs where the machine is worn what do you think will happen when you move it to a position that is not worn? Just asking.


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## wildo (Mar 14, 2017)

Wreck™Wreck said:


> You have just opened a large can of worms for yourself, if you tighten the gibs where the machine is worn what do you think will happen when you move it to a position that is not worn? Just asking.



To be honest, I've had this machine apart and inspected the ways. I didn't see much wear at all, and all the scraping marks were still on all the way surfaces. I suspect that I simply didn't get the gibs tight enough as I had (have) no idea what I'm doing. I think it just needs a gib adjustment.

[EDIT]- But, I get your point. And that would indeed be a whole can of worms!


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## Bob Korves (Mar 14, 2017)

wildo said:


> To be honest, I've had this machine apart and inspected the ways. I didn't see much wear at all, and all the scraping marks were still on all the way surfaces. I suspect that I simply didn't get the gibs tight enough as I had (have) no idea what I'm doing. I think it just needs a gib adjustment.
> 
> [EDIT]- But, I get your point. And that would indeed be a whole can of worms!


Make sure you can slide the table the full length of it's travel before calling it good and putting it back on the mill.  You can also use an indicator to check for movement between the various pieces.


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