Just checking if someone had the same experience.
I cut and engraved a little koi fish with this settings.
1000/100 0 0.25 1 pass
300/full
Then I decided to cut more things with this settings plus some more koi fishes. Same board of masonite. The engraving came out ok but not the cut. Does the machine perform differently when you cut more than one thing at a time?
What can be the problem?
No, not really.
Ever cut this batch of masonite before? If not, your settings may be the problem. How thick is it? If it’s more than about 1/16" you’re probably going too fast.
Try doing a proper material test on it, as described in #6:
Oh I think I actually just figured out your original post’s wording.
You’re saying that setting worked in the past on that same board, yeah? OK well sometimes boards have variance that can make some parts cut better than others. Warp, thickness variation, density variation, humidity levels, etc. You’ll definitely want to do a little testing.
Beyond that, in theory if the engraving made your lenses dirty the power output can be reduced.
If you did a cleaning between jobs, you might have put the lens in upside down, leading to failed cuts. (does the failed cut line look particularly thick? dead giveaway about upside down lens of focus height issue)
Anyway, pictures and more detailed description might help here.
Thank you so much. Yes, it’s the same board. Few hour of difference.
I wonder how “dirty” it is to cut/engrave that stuff.
you might need to clean the optics after each one perhaps. and yes there will be variation in the material. I discovered how much “fun” that can be with that Chalkboard/Whiteboard product people around here have used.
and it turned out the particular CB/WB product I was using wasn’t the same as what other people had. different SKU.
i am going to clean the lens and I will let you know. I think it was dirtier than plain wood. a lot of smoke.
“Masonite” is a brand, and it’s a type of manufactured material very similar to Proofgrade “draftboard”, but also MDF, hardboard, etc.
Many materials are simply unsuitable for certain uses on the laser. The common “black/white” board you can get from THD works great for certain things, but not delicate designs which you are attempting here. I’ve made large pieces for friends (Sugar Skulls, actually) where the outline cut was offset by a few mm. There’s no way I could use it to make a Koi as shown above, it simply would fall apart.
The Home Depot “tempered hardboard” I like to use does indeed require frequent cleaning. I generally keep my settings right on the edge of success, so I’ll wipe down the two windows (side and head) fairly often, the lens a bit less frequently.
I’d like to add in there that not only do your lenses get dirty, but also the fans. If you’re fans are gunked up from engraving the board, then it’s clearing out less smoke, which could also interfere with the laser.
I clean my lenses when necessary, but if I know the lenses are clean and I’m still having trouble with cuts (every other issue discussed above checked out first), I clean my fans. That usually solves any issue I have. I can also tell when they are really dirty when the inside of my lid or the laser tubes starts looking pretty gross. I have some projects where I will start with a clean machine, but I’m cutting or engraving so much MDF, that within a couple of hours, I have to clean all the lenses and fans again.
Well, I was lucky I guess. I tried again on the other edge of the board and they came out good! It looks like this specific side of the board has a problem. 
Thank you for your input. I did clean the lenses but it didn’t look dirty. I guess the problem was a little part of this board. I tried again in the other edge and I was successful. These materials are not even I guess.
I use the HD tempered hardboard often, and it is extremely “dirty”. Clean your optics after every project.
Is there any other type of hardboard you would recommend. I want something that cuts like butter! Lol
The reason I like the HD stuff is that it’s cheap and it cuts like butter for the most part. It’s just a high maintenance option because it burns dirty. But with regular cleaning, it’s a great medium. Haven’t found any other non-PG mdf even close.
Yes, but sometimes I get great cuts and sometimes I have to detach the pieces and cut the pieces with cutter. I really don’t like to have no control over the results. When I think I’ve got it, the right settings etc I didn’t. 
It’s pretty dense stuff. On the cuts, I had to up the power a little at a time. Engraves, sometimes, if it is a detailed engrave, I’ll decrease the power and make 2 passes.
Yeah, the cheap 2x4 “project panels” from THD are pretty consistent. Rough on one side, smooth on the other. I’ve done a bunch of long pass thru projects with it, especially stuff that was painted then engraved, or engraved (with masking) then painted before masking removed. One material that hasn’t sky-rocketed with all the shortages (still under $4!)
It is, however, very dirty - just like Draftboard or any other MDF.
Engraving is fine. My problem is the cut. I will try lower the speed and put full power. Sometimes I use 3 passes and will not cut through the rough part. May I ask your settings? Thank you!
Mostly, I use full power and 165 speed.
