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Bert Kemp
12-18-2014, 11:17 AM
Good Morning everyone well todays problem:)ghess does it ever end LOL anyway I cut a piece of velvet to line a box.and it came up short a1/4 inch all around. I measured twice and double checked the measurements in both corel and lasercut, they were rightn so any ideas why I came up short:confused:

Dave Gates
12-18-2014, 11:53 AM
I had a similar problem where the file I was trying to engrave/cut was a different size. Somehow I had changed an option in Print Preview to "Fit to Page" instead of the "As in Document" option.

Bert Kemp
12-18-2014, 12:39 PM
I have a Rabbit so don't know if that would apply to me, I don't see those options.

Jerome Stanek
12-18-2014, 1:06 PM
did you try scoring a solid piece to see if the fabric shrunk when cut. Also did you have it set to cut to scale

Joe Hillmann
12-18-2014, 1:08 PM
Did the velvet itself shrink because of the heat of the laser? Did you have it stretched tight when you were cutting it and and now that it is loose it shrunk?

Mike Audleman
12-18-2014, 3:38 PM
I would cut a piece of paper and see if its the correct size. If it isn't there is something off in the file. If the paper is the correct size, then the fabric shrunk due to the heat of the cutting in which case I would drastically lower power and raise speed to curb heat damage.

I cut some synthetic silk and it shrank. I ran the speed to max and the power to minimum and bumped power up just until the fabric just barely cut and it came out much better.

Another thought, you might be getting bounce back from your plate/honeycomb/grid. Might put a cardboard or wood sheet underneath.

Bert Kemp
12-18-2014, 5:39 PM
Lasercut was set to the size I wanted it to cut don't know about set to scale were is that setting located.?

Bert Kemp
12-18-2014, 5:40 PM
it wasn't streched just laying loosely.

Bert Kemp
12-18-2014, 5:44 PM
I'll try the paper. My settings are good for the material tho I just barley get a clean cut thru. running 70 spd 20 pwr


I would cut a piece of paper and see if its the correct size. If it isn't there is something off in the file. If the paper is the correct size, then the fabric shrunk due to the heat of the cutting in which case I would drastically lower power and raise speed to curb heat damage.

I cut some synthetic silk and it shrank. I ran the speed to max and the power to minimum and bumped power up just until the fabric just barely cut and it came out much better.

Another thought, you might be getting bounce back from your plate/honeycomb/grid. Might put a cardboard or wood sheet underneath.

Bert Kemp
12-18-2014, 6:32 PM
I ran the paper test and as you can see its still short by approx 1/4 inch 302296so what can be causing this??? Iguess its an 1/8 on all sides if I center the paper.


I would cut a piece of paper and see if its the correct size. If it isn't there is something off in the file. If the paper is the correct size, then the fabric shrunk due to the heat of the cutting in which case I would drastically lower power and raise speed to curb heat damage.

I cut some synthetic silk and it shrank. I ran the speed to max and the power to minimum and bumped power up just until the fabric just barely cut and it came out much better.

Another thought, you might be getting bounce back from your plate/honeycomb/grid. Might put a cardboard or wood sheet underneath.

Bill George
12-18-2014, 7:31 PM
Are you working in Metric in Corel Draw and in the machine or converting over somehow?

Scott Shepherd
12-18-2014, 7:43 PM
Maybe the box is coming up 1/4" too long. :p

Bert Kemp
12-18-2014, 7:56 PM
I lost my box stretcher so I don't think thats it:D
and I convert it all to mm before I send to laser


Maybe the box is coming up 1/4" too long. :p

Bill George
12-18-2014, 8:01 PM
I lost my box stretcher so I don't think thats it:D
and I convert it all to mm before I send to laser

Maybe the conversion is the problem. I have my CD set up in metric, also purchased a metric tape measure. Had to order it from McMaster Carr.

Dave Sheldrake
12-18-2014, 8:25 PM
LaserCUT reads in units Bert, based on the metric system. Would the item be 8 inches long by any chance? (think 25.4mm to the inch not 25 units)

cheers

Dave

Bert Kemp
12-18-2014, 8:53 PM
Dave,
The box ID is 6.25 inchs or 158.75mm by 9.875 inches or 250.8254mm the paper measures 3.175mm short on both sides.


LaserCUT reads in units Bert, based on the metric system. Would the item be 8 inches long by any chance? (think 25.4mm to the inch not 25 units)

cheers

Dave

Dave Sheldrake
12-18-2014, 9:34 PM
Check your email Bert :)

Mike Audleman
12-19-2014, 11:58 AM
I ran the paper test and as you can see its still short by approx 1/4 inch 302296so what can be causing this??? Iguess its an 1/8 on all sides if I center the paper.

Well, then that clearly eliminates material shrinkage as the issue. Must be something between Corel and LaserCut. I don't have ro use LaserCut so I can't do much more to help. I use RDWorks (came with the laser) to actually send the job down. When I tell corel to cut a 4" box, I export to DXF, import to RDworks and then download to the laser for cutting. It comes out 4".

What about scaling in the laser itself or in LaserCut? Possible a scale setting got bumped either in the control panel or in your software? I am pretty sure I remember seeing a x and y scale factor in my settings somewhere.

Bert Kemp
12-20-2014, 12:47 PM
Dave S. is pretty sure we have it nailed down to something in the step count or something, I don't totally understand it but he does and thinks he can instruct me how to fix it. Guess he's good with dummies like me :rolleyes: He helps a lot of us.


Well, then that clearly eliminates material shrinkage as the issue. Must be something between Corel and LaserCut. I don't have ro use LaserCut so I can't do much more to help. I use RDWorks (came with the laser) to actually send the job down. When I tell corel to cut a 4" box, I export to DXF, import to RDworks and then download to the laser for cutting. It comes out 4".

What about scaling in the laser itself or in LaserCut? Possible a scale setting got bumped either in the control panel or in your software? I am pretty sure I remember seeing a x and y scale factor in my settings somewhere.

Bill George
12-20-2014, 1:39 PM
So in CD if you make using the Metric set up a box say 50 mm x 100 mm and send to the laser. What size does it make? You would think if the steps were set up wrong in the laser control panel someone besides you would have noticed and Rabbit Laser, Ie Ray would have corrected.

Clark Pace
12-20-2014, 6:07 PM
Did you change the pulse rate? Or it's something like that. If you change it from the factory settings your measurements will be off.

Bert Kemp
12-20-2014, 8:02 PM
Its off by an 1/8 inch and unless you do something that the size is critical, like making a box lining and it not fitting I don't think anyone would ever notice it was off.


So in CD if you make using the Metric set up a box say 50 mm x 100 mm and send to the laser. What size does it make? You would think if the steps were set up wrong in the laser control panel someone besides you would have noticed and Rabbit Laser, Ie Ray would have corrected.

Bert Kemp
12-20-2014, 8:04 PM
I haven't changed anything its just the way I got it.

Did you change the pulse rate? Or it's something like that. If you change it from the factory settings your measurements will be off.

Dave Sheldrake
12-20-2014, 9:28 PM
Dunno if Ray test cuts on them but slightly out pulse to step rates aren't unusual, if no luck with Ray Bert let me know and I'll write up how to adjust it.

cheers

Dave