[Ntl]

I posted it as a joke since my rails are out by about 3/16h, my frame is not square, and have and am still having to fix just about everything on the machine. At one point Nate offered to take the machine back...I should have taken him up on it, but I thought I could get it sorted out. Dumb mistake in keeping it.

I got the joke when I watched the video. I still haven't heard from Finline about my machine. So much for Life Time support right.

[wmgeorge]

I posted it as a joke since my rails are out by about 3/16h, my frame is not square, and have and am still having to fix just about everything on the machine. At one point Nate offered to take the machine back...I should have taken him up on it, but I thought I could get it sorted out. Dumb mistake in keeping it.

No amount of heat treating is going to fix your machine. I would have opted for my money back. Its too damn bad he has or had a decent product and now its gone down hill. Mine is still working great, but my build is an exception.

[Erik F]

No amount of heat treating is going to fix your machine. I would have opted for my money back. Its too damn bad he has or had a decent product and now its gone down hill. Mine is still working great, but my build is an exception.

I wasn't aware about the frame issues until I tried for a while to fix the drives. When I got the drives fixed and things still were not right is when I chased it back to the last place I would have expected...the frame. The frame is the main selling point and why I went with this machine. I don't use it for my livelihood and have limited amount not time to get on the machine...so I have had it for a while. Trouble shooting these kind of issues an hour at a time once a week when I have free time has proven almost impossible. I have spent a tiny amount of time trying to cut and the last year and a half of my free time trouble shooting.

[Ntl]

No amount of heat treating is going to fix your machine. I would have opted for my money back. Its too damn bad he has or had a decent product and now its gone down hill. Mine is still working great, but my build is an exception.

I'm curious, have you measured your tubing to see if it's metric? I'm wondering if your machine was built in the US or China? I wish Finline would comment on what is going on so we can stop speculation about the cause of the problem.

[wmgeorge]

I'm curious, have you measured your tubing to see if it's metric? I'm wondering if your machine was built in the US or China? I wish Finline would comment on what is going on so we can stop speculation about the cause of the problem.

Well it measures 3.16 3.17 so thats pretty close to 80 mm. But if it was 3.0 you would need to add on for the powder coating.

[micknm]

On the upside, if my earlier assumption is correct - lack of stress relieving of the frame - over time the stresses will equalize and the frame should be stable. Once that occurs, shimming and leveling and paralleling, etc should leave us all with a decent machine. I believe that's the case with ours. It's been running much more smoothly since we realigned everything, but it's been 18 months, so the frame should be stable by now.
On another note, does anyone else have issues with the driver board on the CNCRP P&P box vibrating loose and "causing issues" like spontaneous motor reversals? If so, have you figured out a way to secure the board. We're planning on moving the control box to the wall to keep it from happening again.

[Ntl]

On the upside, if my earlier assumption is correct - lack of stress relieving of the frame - over time the stresses will equalize and the frame should be stable. Once that occurs, shimming and leveling and paralleling, etc should leave us all with a decent machine. I believe that's the case with ours. It's been running much more smoothly since we realigned everything, but it's been 18 months, so the frame should be stable by now.
On another note, does anyone else have issues with the driver board on the CNCRP P&P box vibrating loose and "causing issues" like spontaneous motor reversals? If so, have you figured out a way to secure the board. We're planning on moving the control box to the wall to keep it from happening again.

Pljack had a similar problem with his gecko drives because of the connectors. I'm not sure if his was self built or if he got it from fineline though. I built my own controller so I can't help you out with that unfortunately. Have you gotten your machine leveled out yet? Just curious to see how you dealt with the issue.

Dan

[Ntl]

Well it measures 3.16 3.17 so thats pretty close to 80 mm. But if it was 3.0 you would need to add on for the powder coating.

Mine is about the same 3.18 so much for that theory. It's probably what someone else said awhile ago that the factory screwed him. It's a bummer since the table was still a decent chunk of change. I'm thinking that when I build a new machine I'm going to take this one down to the frame sandblast it weld some flat bar to it and have it machined. I just need to call around and see what the machining cost would be. Or I have a couple other ideas that wouldn't require a full take down, I just need to weigh out the cost.

Dan

[wmgeorge]

Dan if the flat bars were added to the top and they were squared would that be enough? Otherwise I am not sure what the grinding would do other than make it flat but it would still be out of square. How much off is it?

[Ntl]

Dan if the flat bars were added to the top and they were squared would that be enough? Otherwise I am not sure what the grinding would do other than make it flat but it would still be out of square. How much off is it?

Mine is square thank God, it's just the rails aren't flat/level so I have high and low points and have my bearing blocks not tightened all the way so the gantry doesn't bind up. On day I'll try to post some pictures, I'm sure it can be shimed out but it's working how it is for now.

[Erik F]

Mine is square thank God, it's just the rails aren't flat/level so I have high and low points and have my bearing blocks not tightened all the way so the gantry doesn't bind up. On day I'll try to post some pictures, I'm sure it can be shimed out but it's working how it is for now.

Perhaps so thin hard rubber sheeting under your problem areas would help take up some of your issue

[peteeng]

On the upside, if my earlier assumption is correct - lack of stress relieving of the frame - over time the stresses will equalize and the frame should be stable. Once that occurs, shimming and leveling and paralleling, etc should leave us all with a decent machine. I believe that's the case with ours. It's been running much more smoothly since we realigned everything, but it's been 18 months, so the frame should be stable by now.

Hi Mick - no amount of time will help stabilise the internal stress of a welded mild steel frame. Stress relieve can only occur if the material is stressed above the yield point of the material. This is achieved in an oven as at temperature steel gets weaker so the high strain areas stretch to the hot strength of the material reducing the internal stress to the hot strength. Or via mechanical relief in which the frame would be shaken or cold set to stretch the material making the high stress spots reduce its stress over a greater area. This is not as good as heat treat but large structures need a large oven. see https://en.wikipedia.org/wiki/Vibratory_stress_relief

You can stress relieve the frame joint by joint by using an acetylene torch and bringing the joint to red then letting it cool slowly if you can't get it to an oven. If it's a small frame for instance. Not as good as heating the entire frame but better than nothing. Peter

[wmgeorge]

The frames were suppose to be Jig welded and stress relieved. How do you know thats not been done? Just because the tops of the rails were not ground means nothing. My machine is fine and there are more out there as we only see a fraction of the machines he has sold on here. Perhaps 1% or so, but who really knows? The Link to this Forum is still on the FLA website.

BTW Pete have you ever seen a Saturn 2 machine?

[micknm]

Peter, I guess my assumption was based on stress relieving as they used to do with cast iron by putting it out in the "bone yard". I didn't know that steel did not behave in the same manner.

So that brings up another question - would repeated movement of the machine back and forth in the same area tend to relieve residual stress in that area if there were any, similar effect as vibratory stress relieving?

[peteeng]

Hi Mick - There are various metals that "age" like cast iron and heat treatable aluminiums. These have internal metallurgical mechanisms that change over time. This allows various internal strains to redistribute as the grain structure changes. This does not happen in MS. Movement from the machine is unlikely to be big enough to go anywhere near the yield stress of the material so unfortunately this won't relieve stress. Stress relief (SR) is carried out around 600C 1000F at this temp the hot strength of structural steel is about 40% its ambient strength. So a 250MPa steel would only be 100Mpa strength. So any area over 100Mpa would relieve to 100Mpa. There is debate over whether a static structure like a bench needs stress relief at all. If its a dynamically loaded structure like a truck chassis the internal stress contributes to fatigue failure. Since a bench sees very little stress then the internal stress state does not matter and since the metal does not change over time it again does not matter. What does matter is if you plan to machine the bench after fabrication then it will move when you remove metal due to geometric changes. So SR helps in stabilising the bench for that purpose ie it will move minimally when you post machine it. One strategy in benches is to not fully weld the connections. A 100% welded connection is not needed for a bench. So perhaps only 2 sides of a square section perhaps and weld the side that contributes less to distortion. Benches tend to be constructed in a rectangular format to allow storage underneath but this shape tends to warp. If they were triangulated the movement would be less but they would be less user friendly. Another strategy is to braze weld the bench (TIG or torch) so you do not melt the tubes so you do not strain the joints due to the parent shrinkage. This will result in a bench with very low internal stress. Cheers Peter S

[micknm]

Thanks for the detail, Peter. I guess I'm never too old to learn!

[mactec54]

Thanks for the detail, Peter. I guess I'm never too old to learn!

There are many ways that you can stress relieve a steel frame, Heat treatment it just one way they have ultrasonic /Vibratory which in some cases is better then Heat, if the area is small it can be done with a Torch by hand and induction Heating works very well also, shot peening has been used for a long time as well, but each has it's own place and where it is best used

Vibratory has been as successful as Heat treating fabricated steel parts like these machine tables, and does not need blasting after heat treating for paint prep

A way to check your machine to see if it has had any type of heat treatment, is if there is any paint missing and you see shiny places where a disc- grinder has been used then you will know it has never been near any heat, I doubt that any of these machines have ever been stress relieved