# Range of S values for 45 Watt Laser? **URL:** \ **Category:** General Chat\ **Created:** [July 7, 2025, 2:25pm UTC](https://forum.avidcnc.com/t/range-of-s-values-for-45-watt-laser/4972 "2025-07-07T14:25:29Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![kglasnapp](https://avatars.discourse-cdn.com/v4/letter/k/dfb087/32.png) [@kglasnapp](https://forum.avidcnc.com/u/kglasnapp)\ **Post date:** [July 7, 2025, 2:25pm UTC](https://forum.avidcnc.com/t/range-of-s-values-for-45-watt-laser/4972/1 "2025-07-07T14:25:29Z")
What is the range of values for S in the M3 command? S800 only cut .05 not enough to go all the way through a piece of .2 plywood. I have the 45 Watt Laser. ---
**Author:** ![Eric](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/eric/32/3220_2.png) [@Eric](https://forum.avidcnc.com/u/Eric)\ **Post date:** [July 7, 2025, 4:53pm UTC](https://forum.avidcnc.com/t/range-of-s-values-for-45-watt-laser/4972/2 "2025-07-07T16:53:44Z")
0-100 I f you use the Vectric laser model this is handled for you automatically. ---
**Author:** ![jjneeb](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/jjneeb/32/244_2.png) [@jjneeb](https://forum.avidcnc.com/u/jjneeb)\ **Post date:** [July 7, 2025, 10:20pm UTC](https://forum.avidcnc.com/t/range-of-s-values-for-45-watt-laser/4972/3 "2025-07-07T22:20:10Z")
> [@kglasnapp](#): > > S800 only cut .05 not enough to go all the way through a piece of .2 plywood What feedrate are you using, and are you sure its at the proper Z height to be focused? ---
**Author:** ![kglasnapp](https://avatars.discourse-cdn.com/v4/letter/k/dfb087/32.png) [@kglasnapp](https://forum.avidcnc.com/u/kglasnapp)\ **Post date:** [July 8, 2025, 3:44pm UTC](https://forum.avidcnc.com/t/range-of-s-values-for-45-watt-laser/4972/4 "2025-07-08T15:44:47Z")
I have the 40 watt laser. I set the feed rate to 20 inches per minute, the s value to 100 and I was able to cut out the part with 2 passes. My materail was .2 inches. The height of the laser was 22 mm off the material. The advertisement for the 40 watt laser states it should be able cut 3/4 inch material in one pass. Something seems wrong with the s at 100 it should have cut the part and the spoil board. The PWM max value is set to 100. ---
**Author:** ![Eric](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/eric/32/3220_2.png) [@Eric](https://forum.avidcnc.com/u/Eric)\ **Post date:** [July 8, 2025, 7:00pm UTC](https://forum.avidcnc.com/t/range-of-s-values-for-45-watt-laser/4972/5 "2025-07-08T19:00:49Z")
It can do that at around 10IPM or less. It really depends on the material. At the bottom of this page there’s a good list of feeds and speeds that work well: > **[PLH3D-XT8 45W Cutting and Engraving Laser Head](https://optlasers.com/plh3d-series-laser-heads/xt8-cutting-and-engraving-laser-head-for-cnc-machines)** > > Superior for Laser Cutting and Engraving, this 45 W laser head achieves exceptional precision while easily cutting, e.g.15 mm wood in a single pass. As you can see 15mm Pine can be cut at 7 IPM at 100% power. As cool as it is that you can do that, if you’re cutting material that thick you may as well use the spindle. You’ll get better surface finish and things won’t end up catching on fire. The laser is much better suited for fast engraving. The 45 watt gets you a lot higher engraving speeds… that’s where it really shines. ![image](https://canada1.discourse-cdn.com/flex027/uploads/avidcnc/original/2X/5/52d94a4b29f2859da7929972892265aed6ea40ad.jpeg) ---
**Author:** ![jjneeb](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/jjneeb/32/244_2.png) [@jjneeb](https://forum.avidcnc.com/u/jjneeb)\ **Post date:** [July 9, 2025, 3:41am UTC](https://forum.avidcnc.com/t/range-of-s-values-for-45-watt-laser/4972/6 "2025-07-09T03:41:58Z")
> [@Eric](#): > > It can do that at around 10IPM or less. It really depends on the material. Thats right, and this is a case where can and should are different. You can cut 3/4" in one pass, but it is a really bad finish. IMO, you should not cut anything slower than 15ipm with that laser because the finish will be badly burned. Its better to go to 2 or 3 passes before going slower than 15ipm. 3/4" thick is a stretch for this laser. If you want to cut that thick and you really want the tight corners of a laser vs. a router, then two sided cutting works well if you can manage the alignment. However, it looks like there is an issue with focus, or a dirtly lens, or something, because 0.25" baltic birch plywood should cut at 20ipm easily in one pass.