Shaking and Jerking
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Shaking and Jerking
I just upgraded the screws on my machine from 10-1 start to 8-2 start on the X and Y axis. When I jog in the X or Y directions, it runs smooth as silk. Even when the carriage is in the middle of the table at the end and I hit "Go to Zero" It runs very smooth when returning. My problem is that when I carve some lettering that I designed in VCarve Pro 6, mostly on the curves, it is very jerky. The letters come out smooth, but is very shaky while carving the letters. I never noticed this shaking and jerking on the curves before. At first I thought there may be an excessive amount of nodes on the letters. When I checked them, they had minimal amount of nodes and appeared fairly smooth. I've tried all different speeds on the velocity and accel and that doesn't help.
Your thoughts please. Thanks Mike.
Your thoughts please. Thanks Mike.
Mike kearns
noveltysigncarver.com
noveltysigncarver.com
- zeeway
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Re: Shaking and Jerking
If you are using Mach3, check to see under General Config that your motion mode is Constant Velocity. Then under CV control, set the distance tolerance to 1, and stop CV on angles greater than 45 degrees.
Angie
Angie
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Re: Shaking and Jerking
That's what it was! I had it set to "Exact Stop" Now it runs smooth as silk. Man, what a relief. Thank You Angie.
Mike kearns
noveltysigncarver.com
noveltysigncarver.com
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Re: Shaking and Jerking
Hi Angie,
Quick question for you.....I have the same sort of problem. Smooth when running x and y but when I transition into a radius or diagonal cut I get a chatter or not smooth cut just on the radius or the diagonal cut. I talked to manufacturer today and he suggested that I check the ball screws....they are tight. I also checked the general configuration. It is set to constant velocity, cv distance tolerance is checked but it is set to 180 units and the stop cv angles is not checked. And has 0 degrees in the field.
I also get a Pam bumped to minimum setting in the status line. I am running about 20k rpm at anywhere from 30 to 60 on my feed rate. I figure sharp bit and slow speed equals quality outcome.....no so at present. The result are good but I know it can do better. Great machine. I posted another question called chatter.
Thank you in advance,
Mike
Quick question for you.....I have the same sort of problem. Smooth when running x and y but when I transition into a radius or diagonal cut I get a chatter or not smooth cut just on the radius or the diagonal cut. I talked to manufacturer today and he suggested that I check the ball screws....they are tight. I also checked the general configuration. It is set to constant velocity, cv distance tolerance is checked but it is set to 180 units and the stop cv angles is not checked. And has 0 degrees in the field.
I also get a Pam bumped to minimum setting in the status line. I am running about 20k rpm at anywhere from 30 to 60 on my feed rate. I figure sharp bit and slow speed equals quality outcome.....no so at present. The result are good but I know it can do better. Great machine. I posted another question called chatter.
Thank you in advance,
Mike
J&M Carving Creations
Vectric VcarvePro 7.0 and PhotoVcarve
Vectric VcarvePro 7.0 and PhotoVcarve
- zeeway
- Vectric Wizard
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Re: Shaking and Jerking
My CV distance tolerance is 1, and check the stop cv for angles greater than 45. Try that. Do you have a feed screw - if so, is there an anti-backlash device on it?
Your 2000 rpm may also be hurting you, unless you are running a tiny bit. Try slowing that down
Angie
Your 2000 rpm may also be hurting you, unless you are running a tiny bit. Try slowing that down
Angie
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Re: Shaking and Jerking
Hi Angie,
Thank you for the quick reply. I will chang the cv distance tolerance from 180 to 1.....and angles greater than 45 rather than 0.
I am running a a variable speed Bosch 1617, 2.25hp. I am usually running it on speed 5 out of 6 which I'd about 21,500rpm. I use alot of cherry and hard maple. I am not pushing it to hard. When v carving, I am usually using a 60 degree bit with minimal depth. Because I don't feel I am pushing it to hard, it is just odd that on the radius and the diagonal that I am getting this chatter. I am also using a prescision bits collet and don't get any chatter on straight x or y cuts. They cut like glass.
Should I slow down the speed for cherry and maple? I am not having any problem with burning at all and my chipping off the wood seems small but is ok.
any additional thoughts would be awesome.
Thanks in advance,
mike
Thank you for the quick reply. I will chang the cv distance tolerance from 180 to 1.....and angles greater than 45 rather than 0.
I am running a a variable speed Bosch 1617, 2.25hp. I am usually running it on speed 5 out of 6 which I'd about 21,500rpm. I use alot of cherry and hard maple. I am not pushing it to hard. When v carving, I am usually using a 60 degree bit with minimal depth. Because I don't feel I am pushing it to hard, it is just odd that on the radius and the diagonal that I am getting this chatter. I am also using a prescision bits collet and don't get any chatter on straight x or y cuts. They cut like glass.
Should I slow down the speed for cherry and maple? I am not having any problem with burning at all and my chipping off the wood seems small but is ok.
any additional thoughts would be awesome.
Thanks in advance,
mike
J&M Carving Creations
Vectric VcarvePro 7.0 and PhotoVcarve
Vectric VcarvePro 7.0 and PhotoVcarve
- zeeway
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Re: Shaking and Jerking
I run cherry and maple about 14,000 rpm. The purists will tell you this is dependent of the number of flutes and the chipload per flute. They will also tell you your actual chips should not look like dust (but more like chips). I guess if you are not burning the cherry, you can get away with it, but likely will dull your tools faster. Also depends on machine rigidity.
Angie
Angie
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Re: Shaking and Jerking
Hi Angie,
This machine is a Blurry Customs Ironman....and it lives up to its name. It is built like a tank. Two layers of .25" steel on both sides of the gantry. Everything else is either single layer of .25" steel. I will reduce speed and see how it works. I am using 2 flute Whiteside bits for almost all work. Hopefully with the setting changes for both speed and configuration settings it will solve the problem.
Thanks again,
Mike
This machine is a Blurry Customs Ironman....and it lives up to its name. It is built like a tank. Two layers of .25" steel on both sides of the gantry. Everything else is either single layer of .25" steel. I will reduce speed and see how it works. I am using 2 flute Whiteside bits for almost all work. Hopefully with the setting changes for both speed and configuration settings it will solve the problem.
Thanks again,
Mike
J&M Carving Creations
Vectric VcarvePro 7.0 and PhotoVcarve
Vectric VcarvePro 7.0 and PhotoVcarve
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- Vectric Craftsman
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Re: Shaking and Jerking
On this machine, I have NSK rails and bearings. Do you guys have the same setup and if so, how often do you guys lubricate your bearings? What do you use?...Lithium Grease? do you have grease zirks or do you surface apply to the rails? I greased the rails last night in hopes that it would decrease some vibration....I think they are still new enough that it shouldnt be a problem. I have only grease the rails a few times as I do have grease zirks but did not have the needle for lubricating the bearings....so the next best thing was to grease the rails. I have recently picked up a dust deputy for the machine to decrease the dust and will be purchasing a neeedle valve this week to lube the bearings. The combination of grease on the rails and the dust has hopefully not had a negative impact on the bearings themsleves. I ran the x and the y axis several times last night to evaluate the condition of the bearings....there were a couple very small bumps for lack of a better word, when running the rails. I surely wouldnt think that after 40-50 hours of run time that that bearing would be an issue. Do you guys have any thoughts?
Mike
Mike
J&M Carving Creations
Vectric VcarvePro 7.0 and PhotoVcarve
Vectric VcarvePro 7.0 and PhotoVcarve
- zeeway
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Re: Shaking and Jerking
My machine is rack and pinion on x and y axes...but I would think you would not want grease on your rails...especially since you say your dust collection is not functional yet. Greasy rails plus dust will make for rough riding, seems to me.
Angie
Angie
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Re: Shaking and Jerking
Agree with Angie, grease on rails is not a good idea. You could call Blurry for lube recommendations. But sawdust and grease is a bad combo.
The Camaster forum has info on lubing rails. They recommend wiping rails w/ 3in 1 oil or WD-40 to keep clean, and grease quarterly. I wipe my Hiwin rails w/ a clean cotton cloth soaked in 3in1 and wipe off clean.
http://www.camheads.org/showthread.php?t=4563
The Camaster forum has info on lubing rails. They recommend wiping rails w/ 3in 1 oil or WD-40 to keep clean, and grease quarterly. I wipe my Hiwin rails w/ a clean cotton cloth soaked in 3in1 and wipe off clean.
http://www.camheads.org/showthread.php?t=4563
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- Vectric Craftsman
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Re: Shaking and Jerking
Great...thanks for the input guys. Is just as I thought.
Your time is much appreciated. I am trying to get the cyclone hooked up quickly.
Thanks again,
Mike
Your time is much appreciated. I am trying to get the cyclone hooked up quickly.
Thanks again,
Mike
J&M Carving Creations
Vectric VcarvePro 7.0 and PhotoVcarve
Vectric VcarvePro 7.0 and PhotoVcarve
Re: Shaking and Jerking
Another setting in Mach3 is "line look ahead", I find Mach has less issues if this is set at 200. It gives Mach a little more time to anticipate direction changes.
Mike
Mike
Mike E
CuttingandCarving.com
CuttingandCarving.com