Proofgrade setting on cherry plywood did not cut through


#1

I’ve seen a bunch of closed threads on this, so I guess I’ll add my own. Just wasted a perfectly nice piece of medium cherry plywood by trusting the proofgrade cut settings. The back of the sheet barely registered any markings whatsoever – not even close to cut through. Switching to manual shows speed=163. After some trial and error, speed=140 seems to be the correct setting.

  • Sheet is flat and held down by magnets
  • Crumb tray is clear
  • Did not clean any parts, but my GF has seen pretty light use so far so I’d be surprised if that’s the issue

I guess I’ll test first going forward, but it sure would be nice to have some confidence in the PG settings since that’s one of the perks – in theory – of this machine.

EDIT: This thread was closed before I had time to follow up. As instructed, I tried a test print of the standard ruler with default settings on draftboard and got the same results, no cut-through at all. After emailing with support they determined that a warranty replacement of my unit was the best course of action, so I am in the process of doing that. Bummer, but hopefully the replacement will solve this annoying issue. I’m happy that GF is willing to stand by the product like this.


#2

Usually get good cuts right off.
BUT I have also learned it is a good idea to test for full cut before moving anything. It becomes automatic once you start doing it religiously.

Hold board and pull with tape.
Or (my favorite) pull on a cut edge or two with a pick and observe for shift.

That said, the PG settings ARE suppose to work and reporting here that it did not cut through is the way to go.
It could well be a bad batch of PG materials and you would be giving them a heads up to check and verify.
Mistakes happen. I just got some plastics in that were suppose to be 1/16. It even said so on the labeling. It was 1/32 though. They were fast to make it right, since they apparently had a lot of it still around with the wrong labeling and were happy for me pointing it out before they shipped even more of it.
Proof that companies can drop the ball at times.

Giving support the time zone and date//time of the failed cut would also allow them to investigate it easier on their end.


#3

Use the Cherry mostly. Never had a failed cut with the automatic settings. I’m pretty anal about my setup and cleaning.

So, you can be pretty sure the problem is either with your specific machine, a fluke with the material, or your process. Not with the settings.


#4

The last time this happened to me it turned out to be a dirty camera. Try using the lens wipes on all the cameras and see if that helps.


#5

Slight clarification… Windows, lens and mirror can cause cut through problems. A dirty camera lens will not but should be cleaned regularly. Still, good advice and understand the intent of the comment.


#6

I had this happen to me for the first time last night, as well, but with PG Walnut ply. I had cleaned the camera, side lens, etc. carefully before starting the job, as it was for a commission. Nothing cut through. I had to recut everything; not sure yet how it came out as I’ve got to go to work and if I start peeling things I’ll make myself late. I hope the parts are usable, though… sigh


#7

Same happened to me with PG Clear Acrylic medium. It seemed to have a lower power on the vertical lines and could not get through the paper. I chose “manual” from proofgrade setting but rather than give me the actual settings it just said 100% power at 1000 speed, which I am pretty sure isn’t true (maybe engrave has its own custom settings?). Has that older option to edit PG settings disappeared?


#8

Thanks for the responses. This happened last night, approximately 1-2am central time. I will try cleaning the components just in case and will report back if that changed anything. Curious how frequently other people typically clean their components like that?


#9

My process: I shine a very bright LED flashlight on the two windows every couple days inspecting for haze, smudges or dust. If they don’t appear perfectly clean I gently wipe them with the Zeiss wipes. At the same time I wipe the lid camera lens and camera LEDS.

About every week or so, depending on use, I inspect the head lens. If the lens has any noticeable haze I pull it, clean it and at the same time shine the light up at the mirror to see if it has any dust. I try not to wipe the mirror any more than necessary. If the mirror doesn’t show anything visible I don’t touch it. Usually I do all of this without disconnecting the ribbon cable from the head. When the head is removed I also wipe the head camera window and the laser diode window.


#10

Not sure what you meant here. Never been able to change Proofgrade settings other than to select manual. That option is still available.


#11

Believe it used to be that you could click manual and it would show you the proofgrade settings for editing. May be going back to PRU days though. I would love to have that capability. When I click manual from my proofgrade defaults it displays 1000 speed and 100% power.


#12

Those are engrave settings, I’m guessing. Haven’t checked. But sounds like SD Engrave.


#13

Maybe those are the correct numbers. My Pro says 1000 and Full power for Draft and SD engrave with different LPI. The HD says 300/16/450. I get similar engrave numbers for Proofgrade plywood and have been using close to that in manual with decent results on non-Proofgrade. They used to have numbers that used less speed and a corresponding lower power but they changed that to faster/more power quite some time ago. Faster increases the size of possible engraves.


#14

So (pardon my ignorance) does that mean Engrave has a max speed that is limited differently than Cut’s max speed is and power is? Because the engrave was clearly much slower than the machine has moved before (it actually seemed slower than previous engraves, without being all that powerful, which was why I wanted to mess around with the settings in the first place).


#15

The engrave speed is generally much faster than the cut speed.


#16

Eventually, the numbers come down to an inches per minute setting - but the speed scale used in the interface is arbitrary and not any particular unit.

Engrave has a faster max potential head speed than the max potential cut speed.

Engraves will take longer than a cut or a score because it goes line by line. The number of lines is dependent upon the LPI (lines per inch).

If it’s a very small area that’s being engraved (or a cut with lots of sharp bends) the head may never even reach the speed setting shown because it needs time to accelerate and decelerate.

The max power is the max power. Full is full. And everything below that is the same for a cut or engrave. The difference is that you have the potential for less energy to be applied to the material with the faster potential head movement of an engrave process.


#17

Thank you for the helpful info. I will keep an eye on it to see if I can determine why it was moving glacially. Sounds like LPI is worth playing with as well. It’s good to know this 1000 speed 100 % power on engrave isn’t functionally the same as 1000 speed 100% power on cut, I was somewhat expecting it to burn a hole in the table (kidding, mostly) if I chose those settings for manual.


#18

Sorry for the confusion - the displayed speeds and power are the same for both cut and engrave. Cut/score operations are limited to 500 max speed though. Engrave has a limit of 1000.

So a 500 engrave speed would be the same speed (all things being equal) as a 500 cut speed.

Max power is the same between the 2 as well.

What it really comes down to is the total energy delivered to a particular point, which is a function of both speed (time) and power. The laser doesn’t just instantly vaporize through material with a given power setting. It needs the power, and then the time (speed) to do its thing.


#19

No the speed scale for cuts is slightly different to the speed scale for engrave. So 500 engrave is not the same speed as 500 cut.

500 cut is 153 ips.
500 engrave is 147.1 ips.


#20

Thanks. Guess I should have referred to the spreadsheet to doublecheck that statement!

Reading back through this, I see @mnemosyne mentioned something about it not making it through the masking. You should probably start a new thread about that to get it figured out.