BTW I promise I am not trying to be harsh, but everyone’s time is valuable, so I don’t spend a lot of time on padding the message. This information is out there, I promise. You spent hours searching, but when the search was literally “1/4 birch settings” I didn’t think you’d need help figuring out recommended search terms. Sorry if I misinterpreted where you were coming from.
Maybe you read all those already. I doubt it, because what more is there to ask? There’s no magic bullet with settings, eventually you get a general idea and then it comes down to testing. My 1/4" birch can be pretty different from yours. Things like:
slight variations in the piece
how long since you last cleaned the lenses/windows
are you masking or not
moisture content in the wood
…Can all shift settings numbers around. All of this information is out there in the forums, you’re still pretty new, but if you spend the time to really dig, you can learn a ton beyond what we’re telling you here. Especially listen to @chris1, @julybighouse, and @polarbrainfreeze, if you look at their stats, these guys are heavy hitters and know their stuff.
Yeah here you go: If I were to search for this, I would be looking at “inches per minute” as a term and see stuff like the following:
The way a laser works with wood is really complicated, so it’s not often as easy as slowing down the beam by x percent to get x percent more cutting. You get more charring and stuff at slower speeds and so it tends to “gum up” the cut sort of.
I bet your best bet is going to be to do some experiments. If you hunt around, there are lots of posts about cut testing methods that can get you dialed in pretty quickly. They all basically come down to the same thing, make a bunch of test cut lines at different colors and then use the UI to set power and speed across a range. Find the best one, and run with it.
I will be doing trial and error. But man it would have been nice if someone maybe crossed the bridge before and said “hey one time i needed slightly more that 105@100 and xyz worked”.
Isn’t that the point of a community. To be able to share knowledge in an efficient manner.
I have literally spent more time getting told I don’t search and its too hard to answer from you than reading actual insight.
I’ll tell you what, when I’m finished I will post what setting I found hit slightly harder than 105@100 percent in this thread so when someone else asks even a similar question you can get up on the high horse then and tell them they don’t know how to search.
On thick materials, it will also help to change the focal height to a spot below the surface rather than at the surface height. I didn’t see any mention of focal height in the original post.
The beam converges above the focal point and then begin to diverge beyond the focal point wood also works to reflect the beam along the interior of the wood. It also takes a certain amount of energy to pierce the material.
Additionally, flatness gets (more) important at these thicknesses. As non flat material effectively changes how in focus the material is at that particular point.
And even with perfect settings you get imperfect material.
For anyone interested, I have the answer to my questions earlier.
To give everyone the full run down, I have been reading the posts around 1/4 baltic birch for the last few weeks trying several of the different suggesting and still running into inconsistent cuts due to the wood I am using.
I had been trying multiple passes at several different speeds, even going as high as 10+ passes at higher speed to try to overcome the issue of not quite punching through in 5% +/- if the entire path.
Last place I left of before this post was to keep dialing speed down on a single pass to 105 which almost had me there but was too inconsistent. I tried 100 speed and cooked.
This led me to the question as to if anyone had a suggested laser power % that would be slightly more aggressive than 105 @ 100.
I was finding small, simply test patterns inadequate as they would often miss the pins and knots that were causing issues and although they cut fantastically on that small scale, once the full size file was in the glow forge the law of averages tossed me an issue and I couldn’t successfully complete the required cut.
After about 6 hours of trial and error I have been able to identify a speed setting that produces very acceptable results in 1/4 Baltic Birch even when it hits these inconsistencies.
I don’t think any other posts have considered or suggested this but if you are struggle with 1/4 in Baltic Birch. I have had success with:
86 Power Settings
Focal Point (0.21) on (0.23) Material
I found this was the most consistent getting through imperfect materials without becoming overly smoky or causing any char.
I will continue to dial it in over the next few dozen cuts tweaking the 86 power up or down slightly based on results.
So for everyone considering multiple pass as your only option, please consider taking the laser power down too. It saved me on this on.
To reiterate what has been already posted here and countless other threads. Cutting successfully depends on a ton of variables that you might not be accounting for but believe me it makes a difference.
Machine issues first. Are the optics clean including the lense, the Windows, the mirror. Are the fans clean and working up to speed. Are the cameras and the sensor for focusing clean. Are your connections of the head and gantry clean. If you took it apart to clean it is the lens back in the right way?
Material issues specifically dealing with plywood. Is the thickness consistent. Are the plies consistent thickness how are voids repaired? Wood patch vs bondo. What glues where used to bond the plies? How does the glue react to laser beam? Is it flat? Wood moisture content? Where has this ply been stored by you and previously by supplier i.e. Conditioned and moisture controlled? Are your missed cuts along or against the grain? Are they by hidden repairs or knots in the wood. Are you masking one or both sides.
Environmental issues. Temperature and moisture where material was stored and at time of cutting. Was the ply allowed to acclimate. Is the temp and humidity allowed to fluctuate. Is your vent allowing outside air back in when forge is not in use.
I am sure I left out a ton of variables but that is why GF prefers and supplies MDF cored ply. It is a consistent and predictable material.
All that to say that for my supply of 1/4 Baltic birch ply B/BB grade not China made cuts beautifully at full power and depending on the other variables anywhere between 110 and 135 speed. No charring but definitely some cleaning required of the edge to get rid off smoke as well as resin and glue residue. Which brings to mind a whole lot of where did you source your material and what’s in it.
So while I am glad you found a setting that worked for you today. Be mindful that any of the variables listed and possibly missed will cause it to not work in the future.
Try 170 speed, full power, 2 passes. Measure you material with calipers. Set the thickness and focal appropriately via the caliper reading. 170 at full power in a single pass gets me through 3mm baltic birch ply in 1 pass.