# Random Letters Missing During Laser Cut – Only Works Fine One Letter at a Time **URL:** \ **Category:** Community Laser Talk\ **Created:** [July 21, 2025, 10:29am UTC](https://forum.lightburnsoftware.com/t/random-letters-missing-during-laser-cut-only-works-fine-one-letter-at-a-time/176022 "2025-07-21T10:29:25Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![MarcoC](https://forum.lightburnsoftware.com/letter_avatar_proxy/v4/letter/m/54ee81/32.png) [@MarcoC](https://forum.lightburnsoftware.com/u/MarcoC)\ **Post date:** [July 21, 2025, 10:29am UTC](https://forum.lightburnsoftware.com/t/random-letters-missing-during-laser-cut-only-works-fine-one-letter-at-a-time/176022/1 "2025-07-21T10:29:25Z")
Hi everyone, I’m having a strange issue with my laser cutter and I’d love some help figuring it out. As you can see in the picture (from top to bottom, it shows my first to most recent attempts), some letters are randomly missing or partially cut when engraving text. I’m cutting at **speed 50mm/s** and **power 35%**. I’ve already tried applying an **offset** , and then used the **Pathfinder** tool (unite/merge) afterward — but there’s always a small issue somewhere. What’s odd is that **if I cut each letter individually** , it works perfectly every time. But as soon as I send a block of text, I always get one or two letters that don’t cut properly. Has anyone encountered this before or have any ideas how to fix it? Thanks in advance! Marco ![IMG_CA758ED5-BE5C-4BAC-8D16-D1EEA0E93BAF](https://forum.lightburnsoftware.com/uploads/default/original/3X/9/1/91066cd4316d26a67818c455cbb8514216d07920.jpeg) ---
**Author:** ![baricl1317](https://forum.lightburnsoftware.com/letter_avatar_proxy/v4/letter/b/53a042/32.png) [@baricl1317](https://forum.lightburnsoftware.com/u/baricl1317)\ **Post date:** [July 21, 2025, 10:47am UTC](https://forum.lightburnsoftware.com/t/random-letters-missing-during-laser-cut-only-works-fine-one-letter-at-a-time/176022/2 "2025-07-21T10:47:23Z")
If this is a diode laser. Speed is normally set at mm/min and not mm/sec. Try changing that ---
**Author:** ![ednisley](https://forum.lightburnsoftware.com/user_avatar/forum.lightburnsoftware.com/ednisley/32/40455_2.png) [@ednisley](https://forum.lightburnsoftware.com/u/ednisley)\ **Post date:** [July 21, 2025, 12:15pm UTC](https://forum.lightburnsoftware.com/t/random-letters-missing-during-laser-cut-only-works-fine-one-letter-at-a-time/176022/3 "2025-07-21T12:15:05Z")
> [@MarcoC](#): > > encountered this before For a Ruida controller, this is almost certainly due to a communication problem causing a loss of commands & data between the Mac and the controller. If the machine is connected to the Mac through a USB cable, then this is _definitely_ a communication problem. Although you can try a known-good / high quality USB cable, using the controller’s Ethernet connection is generally the best way out. The doc covers the basics: > **[Connect to a Ruida Laser via Ethernet - LightBurn Documentation](https://docs.lightburnsoftware.com/2.0/Guides/RuidaEthernet/)** > > Better software for laser cutters This discussion of a similar problem has some details: > [@Cut off on tokens](https://forum.lightburnsoftware.com/t/cut-off-on-tokens/175078/): > > I make 2" tokens using version 1.7.08 and cutting goes well, The engraving always stops somewhere while engraving. The engraving is well within the circle, but will quit halfway through a word or skip a word entirely (see picture). It doesn’t matter what it says on the token it just stops. If I’m engraving something larger, say 4"X 5"+ it’s never an issue. All help appreciated Folkhero ---
**Author:** ![MarcoC](https://forum.lightburnsoftware.com/letter_avatar_proxy/v4/letter/m/54ee81/32.png) [@MarcoC](https://forum.lightburnsoftware.com/u/MarcoC)\ **Post date:** [July 21, 2025, 7:16pm UTC](https://forum.lightburnsoftware.com/t/random-letters-missing-during-laser-cut-only-works-fine-one-letter-at-a-time/176022/4 "2025-07-21T19:16:09Z")
I have a CO2 laser. ---
**Author:** ![MarcoC](https://forum.lightburnsoftware.com/letter_avatar_proxy/v4/letter/m/54ee81/32.png) [@MarcoC](https://forum.lightburnsoftware.com/u/MarcoC)\ **Post date:** [July 21, 2025, 7:17pm UTC](https://forum.lightburnsoftware.com/t/random-letters-missing-during-laser-cut-only-works-fine-one-letter-at-a-time/176022/5 "2025-07-21T19:17:33Z")
Thank you for your help I’m gonna search on this way. ---
**Author:** ![MarcoC](https://forum.lightburnsoftware.com/letter_avatar_proxy/v4/letter/m/54ee81/32.png) [@MarcoC](https://forum.lightburnsoftware.com/u/MarcoC)\ **Post date:** [July 22, 2025, 7:49pm UTC](https://forum.lightburnsoftware.com/t/random-letters-missing-during-laser-cut-only-works-fine-one-letter-at-a-time/176022/6 "2025-07-22T19:49:23Z")
I ordered a cable that should arrive tomorrow. While waiting, I did some more tests but couldn’t fix the problem… Why does it only happen with this project and not with other files I cut? If it was the cable, I’d probably see the same issue on other cuts, right? Could it be a problem between my font and LightBurn? I feel like the issue started after the last update… ---
**Author:** ![ednisley](https://forum.lightburnsoftware.com/user_avatar/forum.lightburnsoftware.com/ednisley/32/40455_2.png) [@ednisley](https://forum.lightburnsoftware.com/u/ednisley)\ **Post date:** [July 23, 2025, 10:52am UTC](https://forum.lightburnsoftware.com/t/random-letters-missing-during-laser-cut-only-works-fine-one-letter-at-a-time/176022/7 "2025-07-23T10:52:01Z")
> [@MarcoC](#): > > - happen with this project and not with other files > - see the same issue on other cuts > - problem between my font and LightBurn > - issue started after the last update All of that is new information suggesting different tests: - Use cardboard, not spendy materials, until you are confident of the solution - [Restore LightBurn preferences from an automatic backup](https://docs.lightburnsoftware.com/2.0/Reference/ManagingPreferences/#load-prefs-backup) made before the update - Try different fonts in the same file - [Revert to the previous version](https://release.lightburnsoftware.com/LightBurn/Release/) and restore preferences > [@MarcoC](#): > > ordered a cable that should arrive tomorrow If that doesn’t produce immediate relief, put the Ethernet connection on the top of your to-do list while continuing with the other tests. ---
**Author:** ![MarcoC](https://forum.lightburnsoftware.com/letter_avatar_proxy/v4/letter/m/54ee81/32.png) [@MarcoC](https://forum.lightburnsoftware.com/u/MarcoC)\ **Post date:** [July 23, 2025, 8:32pm UTC](https://forum.lightburnsoftware.com/t/random-letters-missing-during-laser-cut-only-works-fine-one-letter-at-a-time/176022/8 "2025-07-23T20:32:43Z")
I appreciate your help 🙏 Thank you. ---
**Author:** ![MarcoC](https://forum.lightburnsoftware.com/letter_avatar_proxy/v4/letter/m/54ee81/32.png) [@MarcoC](https://forum.lightburnsoftware.com/u/MarcoC)\ **Post date:** [July 25, 2025, 9:03am UTC](https://forum.lightburnsoftware.com/t/random-letters-missing-during-laser-cut-only-works-fine-one-letter-at-a-time/176022/9 "2025-07-25T09:03:35Z")
Just wanted to give an update in case it helps someone else! I tried using a different USB C cable, but unfortunately that didn’t solve the issue. I then went out to get an Ethernet cable, followed all the setup steps carefully… and it works perfectly now! A huge thank you to @ednisley for the help and guidance — I really appreciate your support ! ---
**Author:** ![ednisley](https://forum.lightburnsoftware.com/user_avatar/forum.lightburnsoftware.com/ednisley/32/40455_2.png) [@ednisley](https://forum.lightburnsoftware.com/u/ednisley)\ **Post date:** [July 25, 2025, 12:30pm UTC](https://forum.lightburnsoftware.com/t/random-letters-missing-during-laser-cut-only-works-fine-one-letter-at-a-time/176022/10 "2025-07-25T12:30:37Z")
> [@MarcoC](#): > > and it works perfectly now _Yay!_ 🥳 There’s one more thing to check before doing the happy dance: configure the router so it cannot assign the Ruida’s static IP to another device on the LAN through DHCP. If the PC and the Ruida have a direct connection, without using a LAN, then that doesn’t apply, because there is no router. However, if it’s on a LAN, this detailed discussion covers the problem: > [@Hello fellow laser wizards](https://forum.lightburnsoftware.com/t/topic/139052/): > > HELLO, I have a tech problem. My Omtech AF2028 stopped communicating via ethernet. I replaced the cable and still having message, Data not transferred, controller busy or paused. checked IP Adress and replace cable USB connection works fine my modem and hub is fine suggestions are seriously appreciated Bob My Verizon router has a simple way to set the DHCP IP range, but other ISPs / routers make that impossible. Let us know if you run into trouble, as somebody around here may have roughly the same setup.