Surface Finish Issues on New Machine

[ManualEd]

As someone mentioned earlier in the thread, probably something to do with servo tuning.

 

[Houdini]

I hope you get this fixed, I had a similar issue with my brand new Haas DM2, 'basic" servo gain tuning got most of it out, I finally gave up, ball bar shows direction change spikes also, it makes sellable parts, you get what you pay for.

 

[DouglasJRizzo]

It sounds like a paremter

Hello,

I recently purchased a brand new VMC from a company that I would like to keep anonymous for the time being. Let's just say it's a company that has been around for a long time, but they just started selling this type of machine. The important thing is that the machine's weight is about 8600lbs and has X-Y travel of 30 x 20 inches. I was the first shop to take delivery of this machine in the whole country.

I have owned my own shop for about 3 years now and this was the first new machine I purchased. Before this I was using (and still own) a Fryer MB-14. I still work my day job where we have Okuma, Fadal, and Haas machining centers. I have never seen the issue I'm about to describe except for maybe on the Fadal and it's not even half as bad as what happens on my new machine. Not to mention that the Fadal is worth less than 25% of what I paid for the new machine.

The new machine I purchased has a serious issue with "coining" during simple, 2D toolpaths...but honestly it's more like gouging. It occurs when the machine is moving in both X and Y. If I start my feed outside of the material and feed in with a straight line, no coining occurs. If there is a radius on my lead-in then coining occurs at the beginning of the cut. Simple 2D pockets look horrendous.

The machine leaves beautiful finishes when doing 3D surfacing work.

The machine builder has had people out to see the machine from their service team, applications team, and yesterday they had the controller manufacturer come out and take a look. They told me that the problem is the floor in my shop, but I'm not buying it.

The floor in my shop is anywhere from 4-6in thick concrete. They feel that the floor is no good because if you put an indicator on the spindle of the machine and stomp on the floor, the dial jumps around less than 0.0005". Here's the thing though...same thing on my Fryer, but it leaves better surface finishes. Additionally, I put an indicator on a Haas at work and did the same thing and the needle moved more than 0.001"! The Haas leaves perfect finishes.

I feel like the tuning of the machine is just too aggressive and it's "jerking" around when it's changing directions. The machine builder ran a program of mine on one of their showroom machines and it was better, but still not acceptable for the price of the machine.

I'm wondering what you guys think...thanks

It sounds like a parameter tuning or servo tuning issue. Also, is the look ahead active and working?

 

[rklopp]

What's the latest on this mystery?

 

[pcasanova]

might try swapping the x y drives (would think they would be the same) and see if the error follows the drive.

 

[triumph406]

If my 1991 Fadal 4020 gave me that finish I'd take it outback and shoot it

 

[Micmac1]

OP, PM sent.

 

[Rcgiovannani]

Hey guys. Sorry for not getting back on here with updates. It's been crazy trying to get parts out through all of this.

I still want to keep the MTB anonymous because they are doing right by me. The machine is leaving the shop and they will be replacing it with another one.

 

[thesidetalker]

Hey guys. Sorry for not getting back on here with updates. It's been crazy trying to get parts out through all of this.

I still want to keep the MTB anonymous because they are doing right by me. The machine is leaving the shop and they will be replacing it with another one.

Why not name them?

If you get shit service and support, I think others would appreciate to know who to avoid, or be cautious of.

and if the service is good, wouldn't they also like to know? I'd like to know.

It sounds like they're trying to make things right for you. Why not tell us? Not everybody has stellar service and support these days. I'd rather have a less capable machine as long as it is supported and I can have a technician out in a timely matter should there be a problem. A more capable machine isn't too capable when you have to wait weeks for parts or service, should there be a problem.

 

[Houdini]

I agree a lot of vendors try not to take the machine back, I want to know who this is so I might buy a machine from a company with this support.

 

[Ox]

I would like to know if Siemens is this companies normal control, or if this was an option?

I'm guessing that this is NOT an 840?

New Machine Purchase

You doo NOT want a Siemens control in the USA unless you are running a $500K+ European 5x mill. -------------------- Think Snow Eh! Ox Yikes, tell us what you really think. [emoji16] I’ll bite -why? Sent from my iPhone using Tapatalk

www.practicalmachinist.com

-----------

Think Snow Eh!
Ox

 

[triumph406]

Why not name them?

If you get shit service and support, I think others would appreciate to know who to avoid, or be cautious of.

and if the service is good, wouldn't they also like to know? I'd like to know.

It sounds like they're trying to make things right for you. Why not tell us? Not everybody has stellar service and support these days. I'd rather have a less capable machine as long as it is supported and I can have a technician out in a timely matter should there be a problem. A more capable machine isn't too capable when you have to wait weeks for parts or service, should there be a problem.

Might be safe to assume the vendor is aware of this thread and part of the agreement to swap the machine is that their not named. Cos' in all likely hood if their named a few here will jump on the "I had a crap machine from them too" bandwagon. Maybe some significant issues, or the usual "I'm running my coolant at 5%, why are the way covers rusting on my XYZ machine?" complaints

The moral of this story is if you complain about the poor performance of a machine without naming and shaming it could likely be resolved in a civil and responsible manner. Especially if your civil in your approach here (PM) or with the machine builder.

 

[thesidetalker]

Might be safe to assume the vendor is aware of this thread and part of the agreement to swap the machine is that their not named. Cos' in all likely hood if their named a few here will jump on the "I had a crap machine from them too" bandwagon. Maybe some significant issues, or the usual "I'm running my coolant at 5%, why are the way covers rusting on my XYZ machine?" complaints

The moral of this story is if you complain about the poor performance of a machine without naming and shaming it could likely be resolved in a civil and responsible manner. Especially if your civil in your approach here (PM) or with the machine builder.

Perhaps. You might be right about an agreement. Although no harm in the OP replying so if that is the case.

You also might be right about the bandwagon, but to me that wouldn't necessarily sway my opinion one way or another. It sounds like the mtb is trying to make things right. Although it's not clear whether they were going to replace the machine on their own accord, or only acted so if the OP threatened to smear their name here? I also wonder what the timeline is for all these events? Maybe I missed it

Hopefully the new machine leaves better finishes.

 

[rklopp]

It seems like it must be a serious issue if they have to swap the whole machine instead of fixing on site.

 

[Rcgiovannani]

There is no agreement. I would like to think I handled the situation “professionally”. You can get what you want or need from people by being direct while also being respectful. Being an ***hole gets you nowhere pretty quickly.

They are definitely taking care of me now, and I would like them to continue taking care of me so I don’t want to throw them under the bus.

I posted this thread to get help / ideas about what could be causing this because it’s my only machining center and I need it running.

 

[Rcgiovannani]

It seems like it must be a serious issue if they have to swap the whole machine instead of fixing on site.

They could fix it on-site, but they know that this is a small shop and said that the amount of time it would take to go through and fix it would be “unfair” to me. So that’s pretty good customer service in my opinion.

 

[MaxPrairie]

I thought you had mentioned they had run your same program on a showroom machine and it was better but not great. Hopefully the new one gets you running smooth soon.

 

[Rcgiovannani]

I thought you had mentioned they had run your same program on a showroom machine and it was better but not great. Hopefully the new one gets you running smooth soon.

We were able to improve the finish on that machine with certain codes on the Siemens controller.

Used:

JERKLIM[X] = 50
JERKLIM[Y] = 50

Also tried:
"SOFT" command which also improved the surface finish.

Siemens is super powerful, but sometimes it can be overwhelming with how much you can change right in your program. With those adjustments to my program I was able to get pretty decent results. It actually looks even better than the picture in person.

 

[triumph406]

Dunno what your running for endmills, but I've been very impressed with YG-1 Alu-Power endmills, I rough and finish with the same endmill and they have impressive life running in Aluminum. (until the vise/something steel etc gets in the way)

 

[Rcgiovannani]

That's great news they're doing good for you.
Please report back when (if) you know, what they did to fix your original machine. There surely was a combination of something loose in the Z, and servo tuning?

I will. They told me that they would tell when they figure it out. I think it's mostly something being loose on the head.