Cutting a Straight line on FO3015

[LaserMark]

My laser programmer and laser operator are struggling with cutting straight parts. The parts are 11ga CRS 3"x 30" rectangular blanks. When they pull the parts they come off in an hour glass shape. The mid section of the blanks are about .025" smaller than the ends. From my 20 yrs experience I only remember banana shaped parts. We are cutting out of a 48" x 120" sheet, we are using nitrogen for clean cutting. Any help would be great.

 

[3DDave]

Sounds like relieving internal stresses; maybe first a cut on the long side about 1/4 inch from the final outline to let the stresses equalize?

It does seem extreme - you sure no one is pranking you with the model? 'Cause that would be a really fun thing to do.

 

[LaserMark]

I think it is the way they program the parts. I always program them to cut top first and then across the sheet. then downward toward the clamp. that way all the stress is relief is away from the part. If it is a joke I don't think it is that funny. The programmer is saying the Amada rep told him the laser won't cut straight lines. I will have to review his programming methods. I have used Fabriwin since it was DOS. But I know nothing.. would be nice if people would listen to the experienced once and a while.

 

[3DDave]

Won't cut straight lines? At some level of inspection that's true, but it seems unlikely a rep at any level in a company would put it that way. I can imagine any number of defects that could produce irregularities but, if it's a pretty smooth transition, relaxing internal stresses as the cut proceeds is the most likely cause.

Best of luck.

 

[LaserSpyder]

I can cut perfectly straight lines on my Amada FO3015 with no problem, can you post a picture of your part?

 

[jetrep]

Review cutting conditions. Make sure feed rate is too low for heat setting. If cutting too slowly then the material is being excessively heated.

 

[LaserSpyder]

ive never had a part not cut straight because of cutting conditions, or the way the part is programmed lol its kinda silly, these lasers are very accurate, it would help if you showed a picture "a picture is worth a thousand words"

 

[LaserMark]

The part has a 0.020" gap in the middle. it is the same on the other side making is hourglass shaped. I'm trying to get the programmer to change how he processes the sheet. I believe material is moving but just wanted some extra input.

 

[LASERNINJA]

I am curious. Are holes dimensionally accurate? I realize there are no holes in this part, I am wondering if something is loose. Can you cut a 2" square with 45 degree rotation (diamond shape)? It doesn't have to be exactly 2". I would like to know if the cut is wavy after it comes out of a corner.

 

[LaserMark]

Yes, I can cut a 2" square @45 deg. No wave lines. I had to adjust the gantry on our other laser. Not too much fun but it worked. The laser head is tight and the springs and pin are in correct area. I still think material is moving and we need to program it different but my programmer is refusing to listen to me. I have over 21 yrs experience on lasers and programming. What do you do?

 

[lightl]

Are you clamping the material? One common method to eliminate the possibility of material moving is to cut something near the clamp with the clamp on? How about the skids? Have you tried replacing them. Giving joints too keep the material from popping up helps sometimes!