# Question about tramming my 8525 mill



## firemech (Mar 8, 2013)

I have a question regarding my recently purchased 8525 Clausing mill which I am setting up in it's new home. I have trammed the table side to side with no problem, but have a difference of about .006" front to rear, the front being low. I see no way to adjust the mill head fore and aft, nor do I see anyway to adjust the table or vertical dovetails. I wonder if the vertical dovetails have some wear, allowing the table weight to pull it down at the front, but everything looks good with no visual wear and everything seems snug. Wonder if anyone can help point me in the right direction regarding adjusting it or making it more accurate.
Larry


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## tigtorch (Mar 8, 2013)

I am interested in the responses to this post as well.  I have a similar problem with a Millrite.


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## Richard King (Mar 8, 2013)

Put you indicator back in and show us how you trammed your machine.  What do you call tramming?  A indicator in the spindle and moving the saddle in and out and the table left and right, or are you sweeping the table?
Sweeping is mounting a indicator in the spindle and extending indicator rod and indication a 12" circle by turning the spindle?  Take a magic marker and write on the table so we can see what you have.


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## JPigg55 (Aug 17, 2014)

I'm having same issue wit my 8520.
Don't have pictures, but I've swept a dial indicator in the mill head and have it level side to side, but it's out 3 mils front to back.
I think the screws by the knee locks are the adjustment for front to back, but tinkering with them with no luck.
Going to try and post a picture from the manual to show the screws I'm adjusting.


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## Terrywerm (Aug 17, 2014)

This could be a tough one, as this not something that you can simply adjust out like you can on a full sized mill with a nodding head, like a Bridgeport. Snugging up the gibs may help, but it is not really meant to be an adjustment for truing the head to the table. If the gibs are the problem, tightening the knee and table locks before tramming should reduce the difference you are seeing.

 To go further with this, you have to figure out where the problem lies. Is it wear on the column dovetail, or wear on the dovetail on the top of the knee, or is there maybe a bit of foreign material somewhere?  The tiniest piece of foreign material between the head and the ram would have a big effect at the table. Likewise if there is foreign material between the ram and the top of the column, or between the column body and the column top. Regardless of whether you disassembled the machine at all or not, these would be the first places to look for problems. Disassemble those areas, clean them thoroughly and reassemble the machine, then tram again. This ensures that you are taking foreign material out of the equation.

Depending on the new results, you may or may not want to do anything about it. You also need to remember that adding a .001" shim between the column and the column top could make a difference of about .005" or .010" or even more at the table.

So, I guess the first thing you need to ask yourself is "how much difference can I live with?"


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## chips&more (Aug 17, 2014)

The older BP’s with the round ram have the same problem. Sorry, but there is no easy adjustment. If you have cleaned all of the mating surfaces and the problem did not go away, then I’m seeing 5 choices. 1) you live with it, 2) you sell it, 3) you find the area where the discrepancy is coming from and you scrape it, 4) you make an adjustable saddle that mounts behind the head so you can tilt it, or 5) what about a washer/plate that is slightly wedged and put that where the head mounts to the ram??? You could wedge it say 0.010” and then rotate it to suit. The head will not be facing you exactly, it will be ever so slightly skewed, but nobody will be lookin…Good Luck.


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## JPigg55 (Aug 17, 2014)

Thanks for the advice guys.
A little more info, it seems to be riding high in the back. When I zero'd on the front (towards me), it was .003 higher in the back (nearest the column) with the knee locks tightened down.
Funny part was it's closer to level until I tightened the bottom knee lock
Dovetails didn't seem worn when I put it together. I did a complete cleaning and lube before putting it together, but possible I missed something.
Have to take it back apart and look again.
Not quite sure how to go about shimming if it comes to that either.
Thanks again.


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## Terrywerm (Aug 17, 2014)

Since you've already had it all apart, ask yourself how careful you were about cleanliness prior to and during reassembly. If you feel that you were quite cautious, you can probably skip disassembling your machine again. 

.003" is not much, especially over the width of the table. Most parts that a person makes with a mill this size are small enough that you would not even see half of that across the width of the part, and most parts have tolerances of more than .003" to begin with. So ask yourself if you seriously cannot live with that .003".    There is also a big difference between NEED to be rid of that .003"  and WANT to be rid of that .003".    Myself, I know that my parts typically have greater tolerances than that to begin with, so instead of spending my time trying to dial in an older machine, I'll spend my time making the things that I bought the machine for in the first place.

If you really want to dial it in, you could try adding a shim between the head and the ram, but keep in mind that a very thin shim will make a huge difference at the end of the spindle. It is probable that a .001" shim will over correct your problem and will tilt the head even further, but in the opposite direction. One of the other posters mentioned making a spacer disc that is slightly wedge shaped to go between the head and ram. This disc would need to be very carefully made, ground completely true on one side and with a perfect wedge shape of maybe .005" or .010" difference on the other. This may not be the best explanation, but I don't know right off of any other way to say it.


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## JPigg55 (Aug 18, 2014)

Thanks Terry,
Want a good laugh, when I put my mill together (shipped in pieces), I forgot to put the gib bar in.
Think that might help ? LOL


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## Terrywerm (Aug 18, 2014)

Naw.... It's spare precision ground raw stock for making small parts from.  You shouldn't need it...  :rofl:


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## JPigg55 (Aug 18, 2014)

I know what you mean.
Like we say at work...GE...Good Enough.

:roflmao::roflmao::roflmao:


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## barlow l (Aug 18, 2014)

have you swept the table with the knee further down or up?


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## JPigg55 (Aug 18, 2014)

Not yet.
Be the weekend before I can put it back together...with all the parts this time I hope.:nuts::nuts::nuts:


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## calstar (Aug 18, 2014)

terrywerm said:


> Since you've already had it all apart, ask yourself how careful you were about cleanliness prior to and during reassembly. If you feel that you were quite cautious, you can probably skip disassembling your machine again.
> 
> *.003" is not much, especially over the width of the table*. Most parts that a person makes with a mill this size are small enough that you would not even see half of that across the width of the part, and most parts have tolerances of more than .003" to begin with. So ask yourself if you seriously cannot live with that .003".    There is also *a big difference between NEED to be rid of that .003"  and WANT *to be rid of that .003".    Myself, I know that my parts typically have greater tolerances than that to begin with, so* instead of spending my time trying to dial in an older machine, I'll spend my time making the things that I bought the machine for in the first place*.
> 
> If you really want to dial it in, you could try adding a shim between the head and the ram, but keep in mind that a very thin shim will make a huge difference at the end of the spindle. It is probable that a .001" shim will over correct your problem and will tilt the head even further, but in the opposite direction. One of the other posters mentioned making a spacer disc that is slightly wedge shaped to go between the head and ram. This disc would need to be very carefully made, ground completely true on one side and with a perfect wedge shape of maybe .005" or .010" difference on the other. This may not be the best explanation, but I don't know right off of any other way to say it.



Well said! 

Brian


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