Thank for the article. It was interesting but focused more on the tooling then the machines. But at 14xD stick out on a boring bar is crazy!Preparatory to making chips and machine tool rebuilding once again after the move, I've started rereading Moore and Conley.
Additionally, I found this a helpful read on the topic chatter.
Minimizing Vibration Tendencies In Machining
Precision internal machining operations are now carried out almost exclusively using hard-metal or diamond tipped cutting tools. Tool holders are available in a variety of forms to suit the specific machining requirements. The material properties of the toolholder have a large influence on both...www.mmsonline.com
Daryl
MN
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Vibration with Mill and Lathe on Toolbox
- Thread starter sundewzer
- Start date
I can't argue with that but I am trying to find a solution in the meantime that is not avoid 800RPM. Cross braces on the side? I can't really get to the back but I could if I had to. Or would a couple kickers coming off the side at 30 degrees? I saw some videos where people reinforced the bottom of the toolbox but this seemed mainly for the caster which I am not using.
Thank you. I do love my shop size but it is hard to keep warm. I put a lot of insulation in this fall (there was none) but it wasn't enough. When it is freezing out I can't get it about 45f but it gets the job done.
Sundewzer,
I'd also be concerned about a tool box base.
The role of a stand is more than setting a machine at optimal height. As you know it dampens vibration. And there is always potential for multiple and compounding sources of vibration. Identification of possible contributors is critical to the process of elimination. The stand serves to dampen vibration, but where does it originate?
Daryl
MN
Sent from my SAMSUNG-SM-J727A using Tapatalk
I'd also be concerned about a tool box base.
The role of a stand is more than setting a machine at optimal height. As you know it dampens vibration. And there is always potential for multiple and compounding sources of vibration. Identification of possible contributors is critical to the process of elimination. The stand serves to dampen vibration, but where does it originate?
Daryl
MN
Sent from my SAMSUNG-SM-J727A using Tapatalk
Years back I posted what happens when not setting , seating and lagging a machine tool correctly . This applies to smaller thru very large heavy based machines . The results are not pretty . While it may not happen to you , consider someone whipping a bar in that lathe at high speed . Could you run that lathe at a decent rpm with your 4 jaw chuck off center ? Just things to think about when mounting your machines . A tool box serves it purpose as a toolbox , a machine base serves its own purpose . Level it and lag it . Think safety here .
While I agree with the comments about using a more rigid stand, I want to try and address your stated concern about what sounds like a harmonic vibration at 800 RPM. While I am no expert, well to be honest, probably not even qualified to be a novice but I will not let that stop me from sharing an opinion 
. To change a harmonic vibration you have to change the mass distribution of the system. In other words, adding weight, removing weight, moving the weight ... I assume you get the vibrations even when not cutting. Have you tried a different chuck? Remove the Jaws, does it still vibrate? have you measured the run-out, perhaps there is bearing issue. If it is a harmonic vibration, you probably can dampen it to some extent by bolting the lathe to a solid platform on the floor but you may still get accuracy issues at the harmonic frequency until you find and fix the root issue.
. To change a harmonic vibration you have to change the mass distribution of the system. In other words, adding weight, removing weight, moving the weight ... I assume you get the vibrations even when not cutting. Have you tried a different chuck? Remove the Jaws, does it still vibrate? have you measured the run-out, perhaps there is bearing issue. If it is a harmonic vibration, you probably can dampen it to some extent by bolting the lathe to a solid platform on the floor but you may still get accuracy issues at the harmonic frequency until you find and fix the root issue.
Exactly what Bosewell said!
Address the stand problem, but find and fix the problem.
And... understand that bolting it to the floor will still require intermittent level checks and adjustments as the slab moves
Daryl
MN
Sent from my SAMSUNG-SM-J727A using Tapatalk
Address the stand problem, but find and fix the problem.
And... understand that bolting it to the floor will still require intermittent level checks and adjustments as the slab moves
Daryl
MN
Sent from my SAMSUNG-SM-J727A using Tapatalk
While I agree with the comments about using a more rigid stand, I want to try and address your stated concern about what sounds like a harmonic vibration at 800 RPM. While I am no expert, well to be honest, probably not even qualified to be a novice but I will not let that stop me from sharing an opinion
With the chuck removed the vibration is still there but reduced in amplitude. Yes I get vibration when just running the machine. The runout at the spindle less than .0005.
Thanks for you input. I guess I need to make a tool base or a machine box, sort of like Captain Planet. I do want to be able to run a 4 jaw off center so I think that will be a good goal/test.
Here is what I am going to add today to see if it helps.
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I watched a video quite awhile ago where someone use the same toolbox for the same purpose. (Can't find it now...)
They beefed it up quite a bit.
It's basically a sheet metal shell, perhaps reinforcing on three sides would suffice and help.
It's designed to handle a static load not a dynamic one.
I've got my Logan mounted on a sheet metal base sitting a a hunk of reclaimed bowling alley and I can take it to 1000RPM without anything odd happening. But my base was heavily reinforced and welded for it's previous use.
They beefed it up quite a bit.
It's basically a sheet metal shell, perhaps reinforcing on three sides would suffice and help.
It's designed to handle a static load not a dynamic one.
I've got my Logan mounted on a sheet metal base sitting a a hunk of reclaimed bowling alley and I can take it to 1000RPM without anything odd happening. But my base was heavily reinforced and welded for it's previous use.
Put a couple a sturdy brackets from that wood piece under your lathe into the wall studs. Just make sure that there’s some sort of adjustment on both axis....the part bolting to the wall and part bolting into bottom of wood plank where it can be properly shimmed so it doesn’t twist the lathe bed. You’ll only need 2 brackets to stabilize everything. The box carries the weight and brackets would stabilize everything. Not the perfect lathe stand but a quick fix until you can do better.