Engraving is skewed.

[Shevaun Garcia]

Hello, I am having a problem with my engravings coming out skewed. It's completely random as to when it happens. I created the last file in RDWorks and downloaded it to the laser. On the first try, I realized that the speed setting was wrong. {However, it wasn't skewed.} After fixing the speed and re-sending the file, it engraved skewed. The only thing I changed was the speed.

My laser is also engraving very inconsistently. I sent one file to the laser and it was engraving very deep but looked really good {except for the skewed part }. I then did a new engrave file with the same settings, only to have that scan be very light and hardly making a dent in the wood. Any suggestions to either of these problems?

[Jeffrey Aley]

What speed changes did you make? Did it skew when it was running faster, or did it skew when you were running more slowly?

Can you upload a photo of the problem (a picture is worth a thousand words ) ? Ideally, just engrave a square; it can be hard to diagnose problems with a complex image.

As for inconsistency in the engraving depth, is it possible that you're seeing this because of inconsistency in the density of the wood? Have you tried other materials like MDF or even Corian or acrylic?

[Gene Uselman]

If the machine is new you might want to tighten all screws and bolts, especially the set screws on the cogged pulleys [usually 2 per pulley].

[Shevaun Garcia]

Jeffery, I increased the speed. I do have pictures of the original engravings and will attach them, however it's so random, that I'm not sure if I can recreate it on purpose with a square.

Gene, It IS a new machine and you have a good point. I will for sure tighten everything up.

So, I'm thinking you're both right. The combination of higher speed and loose screws may very well explain my skewing problem.

As for the inconsistent engraves, I was using the same piece of wood for images 2 and 3. Hopefully it was just human error on my part and not the laser.

Thank you both for the help!

1.jpg

2.jpg

3.jpg

[Willy Ivy]

As Gene said, there are two screws. You must remove the outer screw to get to the second screw that is under it. The bottom screw secures the pulley to the shaft and the upper screw locks the bottom one in place. Once you get a little wear in and use on the machine, they need to be re-tightened. Usually you don't have to revisit this problem again.

[Gene Uselman]

Also, I think 500mm/s is probably pushing the limits for these machines- I usually use 100, 200 and 300 speed and max safe power, the speed determines the depth. On the set screws, I have heard of two set screws per hole but never actually seen it. There are two different set screw locations tho- and each may have one or two set screws.

[Jeffrey Aley]

I think 500mm/s is way too fast. One thing we have to bear in mind about these machines - the software doesn't prevent us from trying to do things the machine can't accomplish. What I mean is that we can program 100% power (don't!) even though it will damage the tube. We can program 500mm/s, and the machine won't work properly.

If you're interested in pushing the limits of the machine, try reducing the acceleration - you might be able to achieve higher speeds than you can with the default acceleration. You'll also need your mechanics to be perfect - rails properly lubricated, belt tension perfect, no slipping of the drive gears (set screws / grub screws tight), etc.

If you want to reduce your engraving time, try increasing the scan interval. You can trade off image resolution for time (higher resolution = more time). And depending on the material you're engraving, the higher resolution may not be visible anyways.

Regards,

-Jeff

[Shevaun Garcia]

All of the above is great advice. I'm still learning and very new to this, so any input is helpful. Thank you all for your time.