# Weird Omtech/Ruida issue **URL:** \ **Category:** Community Laser Talk\ **Tags:** ruida, firmware, omtech\ **Created:** [September 29, 2025, 5:49pm UTC](https://forum.lightburnsoftware.com/t/weird-omtech-ruida-issue/180851 "2025-09-29T17:49:30Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![TaranEcoDesigns](https://forum.lightburnsoftware.com/user_avatar/forum.lightburnsoftware.com/taranecodesigns/32/111409_2.png) [@TaranEcoDesigns](https://forum.lightburnsoftware.com/u/TaranEcoDesigns)\ **Post date:** [September 29, 2025, 5:49pm UTC](https://forum.lightburnsoftware.com/t/weird-omtech-ruida-issue/180851/1 "2025-09-29T17:49:30Z")
I seem to have found a strange firmware limit in my OMtech 100W (USB1006c) laser. I was doing some materials tests with a file I had created in Lightburn 1.7 using the Shape Properties to set different power percentages for each speed setting. All went just as expected with the engraving tests, but something really weird happened with the cut tests. Basically I discovered that setting a speed of 8mm/s or lower caused the laser to limit the power, rather than use the power setting I had chosen - so the slower test shapes did not cut through, even though the ones with faster speeds did. I then did a test which was just a small box with power set in the usual way instead of using the Shape Properties and again, if the speed was 8mm/s or lower, the thing did not cut through at the same power setting as a cut that worked at 15mm/s. On further investigation I found a “start speed” setting in the controller firmware that was set to 8mm/s and wondered if this was what was limiting the power on slower cuts? Presumably this is a safety feature to try and prevent fires? However, I’ve often seen people talking about cutting at speeds slower than 8mm/s and wondered if they have had to change this in their controllers to make it work? I currently don’t actually need to cut this slow as I’m only using 3mm ply, but I was testing to find the best cut settings that create the least overburn to try and minimise the amount of sanding required after cutting. ---
**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:** [September 29, 2025, 7:01pm UTC](https://forum.lightburnsoftware.com/t/weird-omtech-ruida-issue/180851/2 "2025-09-29T19:01:44Z")
> [@TaranEcoDesigns](#): > > setting a speed of 8mm/s or lower caused the laser to limit the power As you note, that’s lower than the `Start Speed` for at least one of the axes. You can lower it as you see fit. Some earlier discussions: > [@Why RUIDA doesn't light the laser below 10mm/s (80W)](https://forum.lightburnsoftware.com/t/why-ruida-doesnt-light-the-laser-below-10mm-s-80w/120353): > > Hello, I got a vevor 80W CO2 with an RUIDA RDC6445G/S controler. When I want to use high power 85/90% with low speed, the laser is not fired below 10mm/s. I checked the max power on the controller (95%), and I don’t understand why it refuse speeds between 1 and 10%. 11% is fine. This is happening if I use Lightburn or the controller to pilot the cut. Could someone help? THanks > [@Laser misses corners at high speed](https://forum.lightburnsoftware.com/t/laser-misses-corners-at-high-speed/97336): > > Hey Lasers! My laser stops at certain angles and higher speed, moves very very slowly and then moves on to the next point and then continues. This creates the missing corners, which can be seen in the photo. I’d like to work at faster speeds so the cardboard doesn’t burn at the surface that much. How can I solve this? At slow speeds, it lasers the corners cleanly. If there is a better trouble shooting category please feel free to place it to the right places blush Th… > [@New machine power not right](https://forum.lightburnsoftware.com/t/new-machine-power-not-right/14137): > > We got a new Ruida system and I’ve having weird issue with power settings. Hard to explain but here goes It seems despite Rudia display showing proper power level, The laser is burning hotter the faster I go up to a point. So when I go slow 100% does not cut through put at three times as fast I can cut through at like 30%. ---
**Author:** ![TaranEcoDesigns](https://forum.lightburnsoftware.com/user_avatar/forum.lightburnsoftware.com/taranecodesigns/32/111409_2.png) [@TaranEcoDesigns](https://forum.lightburnsoftware.com/u/TaranEcoDesigns)\ **Post date:** [September 29, 2025, 7:24pm UTC](https://forum.lightburnsoftware.com/t/weird-omtech-ruida-issue/180851/3 "2025-09-29T19:24:17Z")
Thanks for that info which confirmed what I had assumed - and for the useful graph in the earlier threads. I wasted a good couple of hours today trying to work out what was wrong with my Lightburn file and it was only by chance I went and looked at the Machine Settings in Lightburn and noticed the two Start Speeds were set to the very speed that was causing the problem!