not vector cutting all the way through

[Nadia Zois]

hi guys :)

i have another issue lately...

when i am cutting stuff [i usually cut wood] it does not vector cut all the way through. even when i put the correct width size in the printing software. i have even added extra power to see if that works. a few times it has. but most of the time it will not go all the way through.

most of them are enough where i can pop them out. some of them get damaged when i try to pop them out though.

i have a versalaser 25watt

the lens is in forcus, the correct width is put in the printing software. i have all the settings correct. [that i know?]

what am i doing wrong??

today for example i cut a lot of stuff..........a few were all the way through as they fell off when i lifted it off the laserbed. but most had to be punched out which caused them to get damage.

it is very frustrating because i have wasted a lot of wood this past week having to redo them because they do not cut out completely.

i am kinda new to using a laser. so i don't know what is up with it and if this is a common problem?

[Darren Null]

First and most obvious question. Are your lens and mirrors clean? They can cack up awfully quickly when burning, particularly with wood, and you'd experience the sort of performance loss you're having.

What sort of wood?
How thick?
Are you using air assist?
Are the non-cut bits in a particular area/s of the table?

[Nadia Zois]

First and most obvious question. Are your lens and mirrors clean? They can cack up awfully quickly when burning, particularly with wood, and you'd experience the sort of performance loss you're having.

What sort of wood?
How thick?
Are you using air assist?
Are the non-cut bits in a particular area/s of the table?

they seem to be clean. i do clean when they look dirty, i do not want to over clean them because i read that is also bad for the lens.

should i clean it even if it doesnt look obviously dirty? like perhaps the wood residue does not look bad even though it is?

i don't remember what kind it is. it is the basic wood you can get at craft stores,

it is 3mm thick

i do not have air assist

nope it is not just in certain places.

it cuts it but not all the way through. if you hold it to the light you can see the tiny holes like in the shape of what is supposed to be cut out. so it is cutting a little but. just not enough to cut it completely off.

[Darren Null]

should i clean it even if it doesnt look obviously dirty
Easy enough to tell if you take the lens out. Sometimes it can look clean in the machine & it's only when you take it out that you can see.

Your mirrors also cack up. This happens quicker without air assist to blow smoke away from the head.

Air assist would also help cutting, as you can laser harder without the wood catching fire.

Presumably you have successfully burned 3mm wood before? Wood wood, or plywood? I have a local supplier & my laser just will not go through their 3mm plywood. I have to buy from a more distant supplier. Something about the glue makes the local stuff laserproof (to me, anyway).

So. Assuming:

Clean lens & mirrors

Even burning (that rules out an alignment problem)

The wood you're burning is the same wood that you've cut successfully before: not an oilier wood.

That your supplier is getting the same sort of wood and hasn't substituted a cheaper/different sort

That it is wood you're burning and not plywood (you can get big variations even in the same sheet...and some brands are tougher than others)

That you're SURE your focus is OK. If you're using autofocus which focuses on the top of the sheet, you're better off dropping the head so your 'X' shape of beam does the most good. If you focus on the top, your beam is cone-shaped, so you get maximum dispersal by the time it gets to the bottom. Try dropping the head 1.5mm & see if that helps.

Having tried all the above:

Is the performance drop sharp or gradual?

and (most disturbing question)

How old is your laser?

[Michael Hunter]

Worth following all the cleaning tips already given - lasering with a slightly dirty lens is probably more damaging than over-cleaning, since the dirt can get "cooked" onto the lens and eventually cause it to crack.

Also be aware that wood is very variable and it could be that your latest batch is denser/heavier than the stuff you got before.

To get consistent results from wood I have the following rules of thumb -
Solid wood : find the optimum setting on a sample and then add 50% more power.
Plywood : find optimum setting and then double the power.

[Joe Pelonio]

A second pass can ensure a clean cut all the way through. If you can still cut acrylic normally then it's not the laser. This is a common problem with warped material if you have no vacuum table. The focus is off at parts of the wood
because it's not totally flat. You can overcome this by applying the wood with a few bits of double sided tape to a piece of sacrificial material that is flat. like a piece of 1/4" acrylic that has had parts previously cut out of it.

[Jim Coffee]

How slow are you going when it fails to cut? What percentage of power are you applying? What is your laser frequency?

On my 45W Epilog I cut 3/32" wood using 100 power, 15 speed, 500 frequency.

[Scott Shepherd]

Could be many things, as you're seeing. Could be the honeycomb pattern on the vector cutting table if you are using that. It'll create a flashback when it hits that grid and if you power is barely getting through anyway, that can leave an attached point.

It could also be the driver. What driver are you using? Make sure it's the latest driver for your machine. ULS has had some issues with that, but I think that was mostly fixed several releases ago.