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Bjorn storoien
04-11-2008, 4:46 PM
Hi

I am new to this forum and i am new to lasers

I am having a hard time trying to choose between Laserpro spirit and Universal pls 460 both 40 w

I have read all treads i could find aboat the subject but im still confused

Anyone with a Universal pls460 or similar that can help me with some questions


Bjorn

Norway

Mike Mackenzie
04-11-2008, 6:41 PM
Bjorn,

What would you like to know?

Scott Shepherd
04-11-2008, 8:35 PM
I have the PLS4.60 and can try and answer any questions about it as well.

Bjorn storoien
04-12-2008, 2:07 AM
Some of my questions are maybe general to all lasers

will there be horisontal lines engraving acrylic even on highest resolution ?

Laserpro says its unavoidable Universal sales rep says that i should get a sandblasted finish without lines



Bjorn

Rodne Gold
04-12-2008, 2:27 AM
No matter what laser you buy , you will get a ridged engraving IF YOU GO DEEP!!!!!!!!
If you engrave normally , ie with little depth , you will get better than a sandblast finish.
I have 3 explorers and 3 spirits , the explorers were problematic , the spirits are wonderful ultra relaible machines.
Go with the machine where you have the nearest and best support if both are similar and do what you want em to. All mainstream lasers in the same price/power/size class are basically alike. Merc or beemer, ford or chev, honda or toyota.......

Bjorn storoien
04-12-2008, 2:53 AM
Hi

It is not deep and the lines/ridges are stronger in parts of the lettering !

It almost looks like the power level has changed during engraving .


I get a feeling that the laserpro rep isnt the expert he claims to be :)

He also had a problem vector cutting rowmark lasermax Black/white with an acceptable result


Bjorn

Rodne Gold
04-12-2008, 3:14 AM
Pass on the laserpro then. I know the spirits are capable of perfect engraving and cutting etc , however if the rep is not clued up and up to speed , neither will the service be.

Scott Shepherd
04-12-2008, 8:34 AM
I think the most important advice I have given and will continue to give is to make the reps show you. NEVER believe their claims, make them prove it to you.

I was at a trade show yesterday and stopped by the Xenetech booth (because we have a Rotary from them), and it was our machine with the new electronics on it, so we stopped. The rep from the factory came over, started talking to us, we told him we didn't have a Xenetech laser because their poor after sales support to us. He then proceeded to talk down our ULS system, speaking poorly about stepper motors, and saying how our laser was the slowest machine in the building.

Nice, really nice.

First of all, our laser is anything but slow. It's faster than our same model year competitor's model we owned, but aside from that, it's been running for close to 8 months without a minute downtime. Keith Outten has had an issue with his Xenetech driver since it was new and they won't fix it. So it was amazing to me how arrogant these reps were when their service and support is so poor. Having the fastest machine on the planet doesn't mean much if you don't support the drivers that run it. I think I offended him. If I did, then good, he deserved to be offended after their treatment of our company. I'm offended by that.

SOME of these sales reps will tell you anything you want to hear. Make them work for the sale and make them show you real life examples while you are there. If they can't give you a quality product while you're there, then skip them.

I do acrylic all the time. What type of acrylic are you speaking about? Colored, clear, 2-ply? It matters on what is possible.

Bjorn storoien
04-12-2008, 12:00 PM
Just plain clear acrylic

He engraved my name with 5mm high italic font nothing fancy

to me it looks like some setting has changed during the engraving process ?

i will try to post a picture of it



Bjørn

Scott Shepherd
04-12-2008, 1:11 PM
In my opinion, engraving clear acrylic is a trial and error process. You can really tweak the settings over time to get excellent results. There are many things you can tweak on it to get the best results, but it does take time. I do a lot of reverse engravable material and it's taken me a while to get the settings dialed in to where it's just about clear once it's burned. Not an easy process.

You can adjust power, focus, DPI, and on the ULS, a couple of other things, to make the results better.

Maybe a better question to you would be - What will you be doing with it? Explain in as much detail as you can without giving anything you don't want us to know away.

Rodne Gold
04-12-2008, 3:19 PM
Scott , getting good results on pex is easy. Any rep demoing a machine should have that dialed in.
The rep lied when he said banding etc is unavoidable, bad to start out a relationship with a lie.

Scott Shepherd
04-12-2008, 3:31 PM
Rodney, it's easy for you :)

On my previous machine, we had a real time trying to get a good result on clear. In fact, we were told by the factory that clear would always have banding on it.

It was only once we got the ULS that we found out that you could indeed get some really nice results without banding. On the 2 ply, that's the part that's taken some time to get dialed in. Too many dpi or too much power and it clouds it up rather than making it clear (at least from my limited experience). If you have tips for getting rid of the clouding, please share. I think I'm dialed in, but you might have some tips that make it even better.

Bjorn storoien
04-12-2008, 4:43 PM
I have started my own business as a side project ,i have a job but i want to do something more creative and see if i can make something more out of it .

I will make signs for the industry and public to get an income and finance the project .

For the creative side i will use the laser for whatever i can make a mark on :)

I am really looking forward to work (play) with it .



Rotary unit ? i read somewhere that you could engrave a round object on 1/3 of the diameter as if it was flat with a good result is this a fact ?

Bjorn

tanx a lot for helping me

Scott Shepherd
04-12-2008, 8:03 PM
i read somewhere that you could engrave a round object on 1/3 of the diameter as if it was flat with a good result is this a fact ?

Not really, no. Depends on the radius of the part you're engraving. With a 2" lens, I think the number is something like 1/8". So if the surface drops off more than 1/8" over the length of the graphic then it won't work. Don't quote me to that number, but I think it's somewhere in that ballpark.

Bjorn storoien
04-13-2008, 4:05 AM
Ok next question :)

While cutting Rowmark lasermax the rep had problems making a fine cut (he is also the Rowmark rep for Norway )

The pieces came out scorched and out of angle (vertical angle not straight )

when i comment this he claims that it allways will be like this using a laser for cutting :confused:

I tought that this was the whole point of using a laser getting precise cuts
and that should be possible on a 1,5 mm 1/16 piece of rowmark ?


Am i wrong ?



Bjorn

Craig Hogarth
04-13-2008, 4:21 AM
not wrong at all. Rowmark cuts nice and clean with the proper settings. Not sure why it didn't cut straight, but he was either out of focus or entire too much power when cutting.

Mike Null
04-13-2008, 7:51 AM
There are only a handful of reps who really understand their equipment and how to use it. Too often they rely on the owners manual and operate accordingly. That sounds great but as you get more experience you'll find that each machine is unique, even those with the same specs. Settings for one 30 watt machine may be different than settings for another 30 watt machine of the same brand.

Saying this another way, reps know they are expected to produce perfect results in their demo but they do not have the time or experience to know what settings to use with every material.

This is why they tend to rely on specific and standard demo items. When you ask them to run a material out of their comfort zone they are likely to produce less than optimal results.

Rodne Gold
04-13-2008, 11:42 AM
If the cut isnt straight , the laser is out of alignment. I dont understand why you persist with this , the rep is clueless and the laser is not set up right. Are ther no other choices for you?

If you read any recomendation here about which laser to buy , you will see that support is the major criteria
What sort of support do you think you are going to get with so many problems right now?
I dont understand why excuses are being made for the rep. If you sell a $20 000 machine, surely it should work 100% right and surely you should be able to work it and not have to bulldust the customer and tell them that defective engraving and cutting is normal..............worst of all , hes the material rep too!!!!!!!
I would never buy a machine that has been demoed to me with such poor results.

Richard Rumancik
04-13-2008, 1:04 PM
Rotary unit ? i read somewhere that you could engrave a round object on 1/3 of the diameter as if it was flat with a good result is this a fact ?

I don't know where the 1/3 rule came from because something is missing from this rule.

The depth of field depends on lenses as well as the quality of the beam. The definition of depth of field is not really based on a scientific phenonema, it is really a convention that is used. Since the laser beam is the shape of an "hourglass" the energy is a max at the "waist" where the diameter is a minimum. Any distance from that increases the diameter and reduces the energy per unit area. So someone decided that if the beam diameter expanded 40% then the beam was still "good enough". This condition occurs on both sides of the waist of the beam. The distance between the two expanded beams is called the depth of field.

To actually calculate a depth of field requires some info about the lens and laser beam which we don't usually know for these laser systems. But for a 2" lens it could be only 2mm (.080"). In the end, however, it is very subjective as the real issue is the quality of the mark you make. Rather than calculating anything, I suggest you do an experiment on a round object. Usually you would focus the beam not on the "peak" elevation of the cylinder but at the half-way point based on the curvature (half-way between min and max elevation.) This is to split the difference. A larger cylinder is more forgiving as it is "flatter". Your eyes will tell you what works better than the equations or "rules".

Without a rotary, don't expect to be able to wrap an engraving very far around a cylinder. But you can engrave successfully along the length of a cylinder (say a pen) without a rotary.