What is the easiest way to tram the head? Obviously the front to back angle is fixed, so only the left to right angle to be located.
I think I just need a dial indicator attachment that I can hold in the quill with a collet. Then I could sweep the right and left side of the table until the indicator shows no difference between sides. Is this the "right" way to do it? Can anyone recommend the proper attachment to accomplish this? Thanks.
Zach
Question for the Rockwell mill owners
Re: Question for the Rockwell mill owners
I have a Rockwell mill, but being an short time amateur, I've only trammed it a few times, not enough to get fast at it or try out different methods. However, even though the RW head cannot nod from front to back, it still needs to be checked. If you find it out of tram, it's probably due to the knee gibs being loose and the knee is sagging towards the front - it's time to tighten them up. When I lock the gib on my Rockwell, the knee is pulled into tram. When I loosen it, it "falls" out of tram just under a 'thou.
Jeff
Jeff
Rockwell-South Bend-Ammco-Delta-Craftsman-Lincoln-Harris-& Harbor Freight too !
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Mike in Iowa
Re: Question for the Rockwell mill owners
One thing that I use on my mill and the mills at school is to take the outer race of a large tapered roller bearing (6-9" OD) scrounged from a salvage yard and put it on your table eyeball centered on your spindle. Make sure you've got the wide foot on your dial indicator and swing it around. Before you put your hard earned cash down for your big outer race at the scrap yard ($1-2 max) take a 1-2" 10 thousandth mic and check the thickness of the race. Both of the ones I have were no more that 1/10,000 out around the whole perimeter. Close enough for tramming in. Makes tramming in a breeze!
Re: Question for the Rockwell mill owners
I finally go mine lined up left to right. I had some trouble because tightening the bolts to lock it down often changes its angle, but I finally have it to the point where I'm satisfied. I have the same trouble with the front/back head alignment. I haven't measured it yet, but I know the just snugging up the knee lock wasn't enough to make a 3 in diameter fly cutter cut equally front to back. I guess a little more investigation is required. Thanks for the pointers.
Re: Question for the Rockwell mill owners
Just snugging up the knee lock will not do it by itself. I should have elaborated that on my RW, I adjusted the gibs until it was almost in tram, and when I lock the gib that takes out that last .001 inch.
Jeff
Jeff
Rockwell-South Bend-Ammco-Delta-Craftsman-Lincoln-Harris-& Harbor Freight too !
Re: Question for the Rockwell mill owners
How tight did you have to make the gib? Does the Z axis still move freely without the lock? I will fiddle with the gib this week, if I get a chance, and let you know what happens.
Supposing that doesn't fix it, what are my other options? I thought of two possibilities. The first would be to shim the holes which the ram slides through to induce a change in angle. I think this would be the best route if there was room for enough shim to correct the problem. If there wasn't a person could hone out the holes a bit, but I don't think I'm up for that.
My other idea is to get a 1/4" plate, clamp it to the table, level the top off with a fly cutter or end mill, and then bolt my vise down on top of that. That way the vise should be perfectly perpendicular to the spindle. The edges of the plate could be trimmed to match the profile of the vise base, so it would be pretty clean looking. I think this would work great as long as I end up doing most of my work in the vise. I'm new to this, so I'm not sure if I'll use the vise for everything or not. Right now I have a small 3" vise, but I think I'm going to get the Magnum 5" mini-mag sold by Penn Tool. This opens 5" as well, so I'm hoping that almost all my work will fit between its jaws.
Any other ideas?
Supposing that doesn't fix it, what are my other options? I thought of two possibilities. The first would be to shim the holes which the ram slides through to induce a change in angle. I think this would be the best route if there was room for enough shim to correct the problem. If there wasn't a person could hone out the holes a bit, but I don't think I'm up for that.
My other idea is to get a 1/4" plate, clamp it to the table, level the top off with a fly cutter or end mill, and then bolt my vise down on top of that. That way the vise should be perfectly perpendicular to the spindle. The edges of the plate could be trimmed to match the profile of the vise base, so it would be pretty clean looking. I think this would work great as long as I end up doing most of my work in the vise. I'm new to this, so I'm not sure if I'll use the vise for everything or not. Right now I have a small 3" vise, but I think I'm going to get the Magnum 5" mini-mag sold by Penn Tool. This opens 5" as well, so I'm hoping that almost all my work will fit between its jaws.
Any other ideas?
Re: Question for the Rockwell mill owners
How tight to adjust the gib? Well, in my case, *just* tight enough to bring it into tram when the gib is locked. What I'm saying is I snuck up on on it - tighten the gib a bit, lock the gib, then check for tram; repeat until good, checking all the while to make sure the knee still moves freely.
How far out of tram (front to back) is it? When I first checked mine it was about .003" off in about a 4" radius. Adjusting the the gib easily pulled it in.
Dont even think about honing out the ram clamps. If its that far out the right way to fix it is to have the ways reground. Leveling the bottom of the vise (with shims or a plate) will only work for a single set-up. Remember, even if the vise is level, the knee is still at an angle (very small!), so when you move the table in and out with the cross screw, the height will be changing.
If you had to, you could try putting a shim in the bottom of the rear ram clamp, in effect nodding the head down to match the angle of the table. It shouldn't take much shim due to the relatively large distance between the clamps. I'm thinking that the RW is so well made you can't stuff much shim in there anyway, but if one got carried away with shimming, one problem might be that the rear clamp now has less contact area/less clamping force around the ram, and the ram is sitting on an angle in the front clamp, also reducing its clamping area/force, so the head might drift out of tram more often.
A flycutter is the largest cutter you'll use, far less often then an endmill, and being larger linearly multiplies the out-of-tram error. I would just adjust the gibs as best you can, and when using smaller endmills the error may be within your tolerance or not even noticeable. When flycutting you can try adjusting the gibs VERY tight to pull everything into alignment (and loosen it afterward when the job is finished), and/or using the smallest diameter flycutter you can live with.
Jeff
How far out of tram (front to back) is it? When I first checked mine it was about .003" off in about a 4" radius. Adjusting the the gib easily pulled it in.
Dont even think about honing out the ram clamps. If its that far out the right way to fix it is to have the ways reground. Leveling the bottom of the vise (with shims or a plate) will only work for a single set-up. Remember, even if the vise is level, the knee is still at an angle (very small!), so when you move the table in and out with the cross screw, the height will be changing.
If you had to, you could try putting a shim in the bottom of the rear ram clamp, in effect nodding the head down to match the angle of the table. It shouldn't take much shim due to the relatively large distance between the clamps. I'm thinking that the RW is so well made you can't stuff much shim in there anyway, but if one got carried away with shimming, one problem might be that the rear clamp now has less contact area/less clamping force around the ram, and the ram is sitting on an angle in the front clamp, also reducing its clamping area/force, so the head might drift out of tram more often.
A flycutter is the largest cutter you'll use, far less often then an endmill, and being larger linearly multiplies the out-of-tram error. I would just adjust the gibs as best you can, and when using smaller endmills the error may be within your tolerance or not even noticeable. When flycutting you can try adjusting the gibs VERY tight to pull everything into alignment (and loosen it afterward when the job is finished), and/or using the smallest diameter flycutter you can live with.
Jeff
Rockwell-South Bend-Ammco-Delta-Craftsman-Lincoln-Harris-& Harbor Freight too !
Re: Question for the Rockwell mill owners
I'm not sure how for mine is out of tram front to back. Just sent my dial indicator back because the mag base that cam with it is defective, so I can't measure until I get a new one. I did snug up the knee gib, but I didn't see a lot of diffence. At this point my comparisons were made visually using the cut left by a 3" diameter fly cutter. When I had the gib super tight and locked down there was not an appreciable difference from a normally adjusted gib. On the bright side, the knee gib was looser than it needed to be when I started and snugging it up did improve things slightly.
You are right about the plate idea. The only way to make it perpendicular to the spindle would be to level it in a single cut with a huge fly cutter or face mill, which would be impossible. Even if you could do it, you would then be faced with cuts that would increase in depth as you feed the y axis.
The more I think about this, the more I am starting to realize that it cannot be fixed without a regrinding the ways. Even if I were to get the spindle perpendicular to the table with shims, then the spindle would not pe parallel to the vertical way. So really it's just a question of where you want your error.
I guess it you got the head trammed perfectly to the table, and then only used the spindle for increasing the depth of the cut, you could theoretically still make a perfect part.
I think that at this point I need to wait to get my new dial indicator and see how far out it actually is. In any case I doubt that it would justify a regrind. Even if I did have it reground I would have doubts that the grinder could get the alignment much better.
I wonder how much mis-alignment is normal. I bet all used mills are out a certian amount. It would just be harder to detect on a bridgeport style machine with an articluated head. I bet most blokes get the head square to the table, cut away, and never know the difference.
Zach
You are right about the plate idea. The only way to make it perpendicular to the spindle would be to level it in a single cut with a huge fly cutter or face mill, which would be impossible. Even if you could do it, you would then be faced with cuts that would increase in depth as you feed the y axis.
The more I think about this, the more I am starting to realize that it cannot be fixed without a regrinding the ways. Even if I were to get the spindle perpendicular to the table with shims, then the spindle would not pe parallel to the vertical way. So really it's just a question of where you want your error.
I guess it you got the head trammed perfectly to the table, and then only used the spindle for increasing the depth of the cut, you could theoretically still make a perfect part.
I think that at this point I need to wait to get my new dial indicator and see how far out it actually is. In any case I doubt that it would justify a regrind. Even if I did have it reground I would have doubts that the grinder could get the alignment much better.
I wonder how much mis-alignment is normal. I bet all used mills are out a certian amount. It would just be harder to detect on a bridgeport style machine with an articluated head. I bet most blokes get the head square to the table, cut away, and never know the difference.
Zach
Re: Question for the Rockwell mill owners
I Do not have a rockwell, but I use a cutter (large dia.) make a couple cuts to see how much step I have. then make fine adjustments til I have it in an acceptable range. Slow? Sure it is..... but once done you are just about as good as you can get. By doing it this way you are also accounting for any flex in your quill etc under actual cutting conditions. Not saying this is "the right way" Just my 2 cents........
If it works Don't fix it....
Re: Question for the Rockwell mill owners
I agree, there's no need to worry until you get your indicator. Plus, there's a few more possibilities that are easier fixed than a re-grind of the ways.
Of all the parts and areas that can wear, I would think the Z-axis ways are the last to go. What overall shape are the X & Y ways and the feed screws? If they are halfway decent, than I can't see the Z ways being worse - it just isn't used as much as X & Y.
The problem might be the quill bearings - perhaps they were put together with too much preload, causing one of the bearing races to deform and now the quill is slightly cocked. Or even simpler, maybe the quill was loose when you checked for tram. You can adjust the amount of clamping on the quill lock by adjusting the nut in the back. Or maybe there is a ding/burr/imbedded chip on the side of the quill housing/bore that is holding the quill housing at an angle. Or similarly a ding/burr/chip on the Z way/s that just happened to be at the height where you were checking the table for tram. It's very simple to remove/slide out the quill to inspect and clean, and to stone away any burrs you might find on it, the bore, or the ways. If eventually you think it might be the bearings, then I can direct you to resource over at Yahoo groups for working on your Rockwell.
As I said, lots to check, but much easier and far cheaper than having the ways ground. Just take a good close look at your machine and logically work your way around and through it, eliminating the simpler items first.
Jeff
Of all the parts and areas that can wear, I would think the Z-axis ways are the last to go. What overall shape are the X & Y ways and the feed screws? If they are halfway decent, than I can't see the Z ways being worse - it just isn't used as much as X & Y.
The problem might be the quill bearings - perhaps they were put together with too much preload, causing one of the bearing races to deform and now the quill is slightly cocked. Or even simpler, maybe the quill was loose when you checked for tram. You can adjust the amount of clamping on the quill lock by adjusting the nut in the back. Or maybe there is a ding/burr/imbedded chip on the side of the quill housing/bore that is holding the quill housing at an angle. Or similarly a ding/burr/chip on the Z way/s that just happened to be at the height where you were checking the table for tram. It's very simple to remove/slide out the quill to inspect and clean, and to stone away any burrs you might find on it, the bore, or the ways. If eventually you think it might be the bearings, then I can direct you to resource over at Yahoo groups for working on your Rockwell.
As I said, lots to check, but much easier and far cheaper than having the ways ground. Just take a good close look at your machine and logically work your way around and through it, eliminating the simpler items first.
Jeff
Rockwell-South Bend-Ammco-Delta-Craftsman-Lincoln-Harris-& Harbor Freight too !
Re: Question for the Rockwell mill owners
Thanks for the pointers. As long as I can make parts within .001 I am happy, and I think I should be able to achieve that with some minor tuning. I certianly do not plan on doing any drastic rework to gain and extra .0005. If I ever need to be that accurate I will sell the machine and buy something of higher quality. I would love an Aciera F3.