Choosing the right laser

[RockyAussie]

After finding out as much as I could about lasers and their practical uses with leather I decided to go with a small diode laser. This video is the first in a series I hope to share with you as I go in finding ways and developing methods and improvements related to leather working and laser. Many reasons along with cost led me to go with the small diode laser to start with and I can honestly say I have been surprised and delighted  on my findings so far. The CO2 lasers that at first looked so tempting lost their gleam when I discovered that the tubes that they come with will often fail within 6 months or less and a good quality honestly branded Reci tube will likely cost around a $1000 or more. Another finding is that the small dot of a 2500mw laser gives excellent detail for fine engraving (burning in) and along with a program called 2T Laser it is possible to get a dxf file once done in a decent Cad program to cut with different power and time settings all in the one file. I have had some success with cutting leather be that it takes several passes but for my prototyping work that is now a major time saver. Even the little one shown here can be moved around over the top of a whole hide if you wanted to do it in sections or as can be seen later a very large version I am working on can do larger than poster size and all for a few hundred dollars. (So far). Watch it and comment and follow if your interested to see more.

 

[dikman]

Thanks mate, most interesting. Unfortunately I can't think of a use for one , otherwise it could be a bit of fun to play with.

Edit: I just had a look on ebay and 2500W units that look to be the same as yours are going for about $280? Any idea what's the thickest yours can cut in one pass?

Edited December 31, 2018 by dikman

[RockyAussie]

8 minutes ago, dikman said:

Thanks mate, most interesting. Unfortunately I can't think of a use for one , otherwise it could be a bit of fun to play with.

Keep a look out as I already discovered way more uses than I every thought to start with and that new printer of yours would come in handy on making one for yourself. I printed up several pieces in the big one I am making like the cable chain holders and some corner fittings and that helps keep the cost way down. I am hoping to try it out on cutting some 3mm black acrylic soon as I believe that is possible.

[RockyAussie]

Here's a couple of pictures of the prints...note: the mounting block around the motor to the cable chain and the piece that alows you to slide along the channel to get the chain positioned perfectly.

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Below a couple of simple little corner block holders that allow the control board to be held and slide positioned into place.

[RockyAussie]

31 minutes ago, dikman said:

Edit: I just had a look on ebay and 2500W units that look to be the same as yours are going for about $280? Any idea what's the thickest yours can cut in one pass?

Pretty low and depends on the leather type ...mostly I go at about 1/2mm at a time but I have accidental cut through about 2mm in about a second before I realised it was not moving. If you turn it on without the safety button on, it starts at full power if it is not being controlled by from the computer program.You can set it in the program to do how ever many passes you like. I am playing around with a 5 watt one at the moment that cost me just over a hundred and it burnt a hole in a 3 ply cardboard box about 12" away before I even realised it. That was a shock and a fast learning lesson.

[bikermutt07]

That is awesome. Keep the videos coming as much as time allows.

[maxdaddy]

Thanks for sharing that information. I'm sure that there's a laser cutter in my future and every time I watch one in action I think of several things that I could do with one.

I like how you use it for a big variety of different jobs. It was obviously a good investment for your shop. 

[chrisash]

Nice video

My worry would be the open structure of the laser as a safety point , where as the closed box normally associated with lasers provides near impossible risk, I imagine there may be a slight risk being open when people become complacent with its use

Do you think i am seeing something that is not there

[RockyAussie]

5 hours ago, chrisash said:

Nice video

My worry would be the open structure of the laser as a safety point , where as the closed box normally associated with lasers provides near impossible risk, I imagine there may be a slight risk being open when people become complacent with its use

Do you think i am seeing something that is not there

No, I believe as you do that there is an unacceptable risk with it being open as it is and is one of the reasons that I have made the big one in the box shape I have. I had ordered before Christmas black acrylic sheeting cut to size for it but unfortunately they did not get it done and I will have to wait a couple of more weeks now before they get back to work. This will also act to keep the structure more square and rigid. Fans,extractors, Z axis lifters, bigger diode lasers are all on the drawing board yet to do. 

[garyo1954]

Not sure where you got your information on CO2 lasers. It does paint a pretty bleak picture compared to the reality of having one.

A lot depends on how you take care of your machine as to the life of the tube. Overpowering it for extended periods, not using distilled water,  high water temperatures and extreme climate changes all play a part. Some materials will play a big part in how long the tube, the lens, and mirrors, or even the machine, lasts. Some materials produce chlorine and/or corrosive gases, and even toxic gases (such as chrome tanned leather). PVC/and most plastics should never be cut. You'd be surprised how many times people will laser plastic and then wonder why they ended up with a gooey mass that is nerve wracking to clean up. Or the number of lasers lost to fire due to trying to cut and engrave a flammable material. Leather produces a dead flesh smell and can leave soot on the mirrors and lens which needs to be cleaned with alcohol. (Mirrors should be cleaned as a maintenance task in any case.)

I laser wood, (cedar, poplar, basswood, oak, pine),  extruded acrylic, and veg-tan (tooling leather), glass, and anodized/painted dog tags and ID cards. Timewise you spend more on layout than on actual machine time. Very rare to hear anyone complain of a machine timing out and when it does happen they are generally trying to run an intricate oversized layout at 1000DPI, in other words, pushing the limits of the machine, software, and computer.

Now the last time I replaced my 40W tube was September 2017 and its still going strong. I run my laser 4 to 6 hours daily and there are days it runs 8 to 12 hours.  Yes, the tube is only guaranteed for 1000 to 1300 hours of use.  But most things you buy these days have a 30 to 90 day warranty which is equivalent to that 1000 to 1300 hour guarantee. Some claim the tube has a shelf life of two years due to the gases. Others claim to use the same tube for years beyond that.  Two years seems to be the average in my case.

A replacement tube is costs $90 to $125 for a 40W. You'll even find 100W RECI tubes for less than $800, but you don't need a 100W laser to engrave or cut leather. A 40W CO2 does the job just fine. 

Finally a 40W CO2 Chinese laser can be had for $400 or less. All said and done, the information you were given does not match the reality of actually owning ang using a 40W laser.

[RockyAussie]

On 08/01/2019 at 6:47 AM, garyo1954 said:

Not sure where you got your information on CO2 lasers. It does paint a pretty bleak picture compared to the reality of having one.

A lot depends on how you take care of your machine as to the life of the tube. Overpowering it for extended periods, not using distilled water,  high water temperatures and extreme climate changes all play a part. Some materials will play a big part in how long the tube, the lens, and mirrors, or even the machine, lasts. Some materials produce chlorine and/or corrosive gases, and even toxic gases (such as chrome tanned leather). PVC/and most plastics should never be cut. You'd be surprised how many times people will laser plastic and then wonder why they ended up with a gooey mass that is nerve wracking to clean up. Or the number of lasers lost to fire due to trying to cut and engrave a flammable material. Leather produces a dead flesh smell and can leave soot on the mirrors and lens which needs to be cleaned with alcohol. (Mirrors should be cleaned as a maintenance task in any case.)

I laser wood, (cedar, poplar, basswood, oak, pine),  extruded acrylic, and veg-tan (tooling leather), glass, and anodized/painted dog tags and ID cards. Timewise you spend more on layout than on actual machine time. Very rare to hear anyone complain of a machine timing out and when it does happen they are generally trying to run an intricate oversized layout at 1000DPI, in other words, pushing the limits of the machine, software, and computer.

Now the last time I replaced my 40W tube was September 2017 and its still going strong. I run my laser 4 to 6 hours daily and there are days it runs 8 to 12 hours.  Yes, the tube is only guaranteed for 1000 to 1300 hours of use.  But most things you buy these days have a 30 to 90 day warranty which is equivalent to that 1000 to 1300 hour guarantee. Some claim the tube has a shelf life of two years due to the gases. Others claim to use the same tube for years beyond that.  Two years seems to be the average in my case.

A replacement tube is costs $90 to $125 for a 40W. You'll even find 100W RECI tubes for less than $800, but you don't need a 100W laser to engrave or cut leather. A 40W CO2 does the job just fine. 

Finally a 40W CO2 Chinese laser can be had for $400 or less. All said and done, the information you were given does not match the reality of actually owning ang using a 40W laser.

Thanks for sharing your input on your experience with owning a C02 laser. I am glad to see a positive reflection on owning one and I would love to see more if you have any on how they are useful in the leather working world.

It was not my intention to rubbish a Co2 by any means, as I said there were many reasons I felt best to go with a diode laser to start with. Firstly at the time when I researched into this most people that found their lasers useful with leather were seldom using them for cutting. By far most are using them for engraving purposes. Those that were using for cutting in a business like way were using 100 watt upwards and the prices and the size at that point goes up into the $thousands pretty quick.

2. The cutting size of 8"x12" (96sq") that most of the 40 watt lasers you mention come with is way too small for my uses. The little A3 Eleksmaker can use 12"x 15" (180sq") and that is not really big enough either but is nearly twice as big. A lot of my bag patterns go bigger than A3 size. When I found out I could cut card stock with the little laser I was pretty much hooked as that meant when I drew a pattern up in my cad program I did not have to print it out and then cut it out to recut it out again on leather by hand. The little A3 laser set me back about $300AU to start and once it showed its potential and paid for itself in about a week making product boxes I decided to spend another $300 thereabout to make the cutting area 27"x35"(945sq") There is a few dollars in that for an extractor fan ducting etc that should all go in place this weekend along with the acrylic shrouding. Already before this I cut enough product boxes in the last 2 days to pay for the extra cost.A lot of the pieces in these boxes are bigger than A4. 

3.There are no mirrors to line up + focus or keep regularly clean and no water pump that needs distilled water or chiller.

Mostly cutting the leather leaves some charcoal residue that can be time consuming to clean up and is therefore a reason not to consider it for any production type work. Even the best powerful lasers still have this problem and in most cases if you are doing production like me you would use a clicker press and knives. The cutting time per piece is around 30 seconds from 1 piece to the next. Also knives tend to push the leather down and give a better look to the job. Getting knives made can sometimes be expensive and doing some sales testing on a product that is laser cut can be of help and in some cases like this pattern of an non stitched product shown below the knifing costs would be very expensive and you would really want to be sure its a seller by trialling with a laser first.

AS for the life of the diode laser ....this depends as well on how hot and long you are going to run it but this link was the first one google showed me when I asked how long does a diode laser last? https://www.myomron.com/index.php?action=kb&article=673

If I get 50,000 hours I would be

I am working on a cooling fan over the top of the laser at any rate with the idea of using the blow by to give some air assist at the same time. Will post that when done.

Here is a couple of the progress pictures so far. This one shows the size difference

This one shows the wiring and everything else is working as it should so far.

I will have some more pictures and news Monday I think.

[garyo1954]

RockyAussie,

Very nice! I didn't quote your post due to the pictures but you do wonderful work, not only on leather but the machine as well.

A point you made was the 200mm by 300mm (8" by12") bed is key. Obviously the bed can be, and many have, expanded those to whatever custom size they wish. (A laser guy in Sweden sells an expansion kit for a 400mm by 700mm bed which can be fitted into the existing chassis with some modification). So the size of the bed is no longer a deciding factor.

Prior to purchasing the CO2 I gave serious thought to retrofitting a diode laser to my CNC router, which is no longer used. It didn't take long to realize that a CO2 laser would open up the ability to work with any organic material,  everything a diode laser would plus glass and thicker materials. While there is nothing detrimental to the diode laser in general, there is more upside to the CO2 as this article point out:
 

Commercial Laser Engravers

Most ‘small’ commercial laser cutters and engravers use a CO2 laser, typically with a power of 20-40W (20,000- 40,000mW). A 20W CO2 laser can typically cut 3mm plywood and 8mm acrylic easily at full power and will run at ~5-10% power (1-2W) to engrave wood, cut paper etc.

CO2 lasers are commonly used simply because they are the cheapest way to generate laser light at these power levels.

The power output of common semi-conductor lasers (laser diodes) is much lower and the cost of laser diodes increases above a couple of watts to the point where they are no longer economic to use compared to a CO2 laser.

It is however possible to use laser diodes to engrave wood, cut thin paper, balsa wood and pattern resist layers for PCB etching. Reducing the cutting/ engraving speed is often required.

Of course at the time of the purchase,  leather was never a thought. Prior to October 2018 when deciding to do something different for Christmas gifts I had never worked with leather.  A bag of RealLeather scraps and some testing changed that. Along the way it was learned that some sellers send their leather and/or their patterns to be laser cut. (They sell the patterns which are cut in acrylic.)

With a CO2 laser, different leathers require a different power and feed to produce the best finish and by no means have I mastered that, but a 40W CO2 is plenty capable of cutting 4mm leather with 10% power at a speed of 200-250mm per second. There seems to be no need to run a CO2 at full power. Nor to run speeds of 350-400mm per second as many do. Its not a race and no one gets a trophy for finishing first. So most leather is run between 9% and 11%,  and in some cases such as thicker leather that will only cut about halfway through leading me to conclude one could laser cut and hand bevel a pattern of choice.  That's the plan for this weekend.

But hand tooling is quite intimidating at this point. Starting a basket weave on a belt, wouldn't you know January 1, and seemed to be doing pretty good, getting relaxed when the someone in the neighborhood decided to set off the most ear-shattering, nerve-jarring, very possibly a homemade nuclear device of the most hideous mankind has ever produced. And all this about the same time the mallet was coming down to strike. After that, not being able to get back to that peaceful frame of mind,  and several other mis-strikes, we produce a ruined belt.

So by no means do I consider myself more than a novice/trainee when it comes to leather. Capable, but far from fair to middling. As you can see, bracelets were the eventual Christmas gifts. One of the first pieces laser cut was the Karen bracelet taken for fitting. It did not, so rather than junk the piece she suggested punch a hole and it would become a keychain. (She did get another bracelet.) And she's brought this back asking for a bracelet for her daughter using this as the measurements.

And as can be seen I'm still learning and experimenting with different leathers and trying different things. But as you say cutting leather with a any laser does produce charcoaling which can be a tedious side job. My solution, as yours, is to do the engraving and use a straight edge and utility, X-acto, or even a circular blade. (A clicker press is a new term) 

All told, it wouldn't appear to make a huge difference which laser one chooses if the focus is leather.

[LatigoAmigo]

1 hour ago, garyo1954 said:

a 40W CO2 is plenty capable of cutting 4mm leather with 10% power at a speed of 200-250mm per second.

I'm floored. I use a 100-watt CO2 laser, on 5-6 oz. leather (which is 2 mm), and must make multiple passes at 75% and 20 mm per second. So my cutting (I don't cut veg tan) takes me much more time. Do you have any tips for me that might help speed up my production? 

Slow, or not, I am very happy with the results of this machine.

[bermudahwin]

Excellent thread, thank you

Harry

[garyo1954]

14 hours ago, LatigoAmigo said:

I'm floored. I use a 100-watt CO2 laser, on 5-6 oz. leather (which is 2 mm), and must make multiple passes at 75% and 20 mm per second. So my cutting (I don't cut veg tan) takes me much more time. Do you have any tips for me that might help speed up my production? 

Slow, or not, I am very happy with the results of this machine.

LatigoAmigo, thank you for pointing this out. Its total nonsense on my part to say one can cut through 4mm material at 250mm/sec. It's a misthought that should have never left my fingers nor my brain without some editing on my part.

I engrave leather at 250mm/sec and cut with a straight knife. To laser cut through leather the speed would never exceed 20mm/sec. Most likely it would be closer to 12-15mm/sec since those are personal default values. 

Here's a sideview of the Karen bracelet from the last post. Its 3.47 mils and you can see some of the char line where it was lasered.

 

My apologies for the misstatement. I'd like to say it won't happen again, but likely it will.  Thank you for bringing that to my attention LatigoAmigo.

(I had a much longer post but a crashed tab lost it. I will rewrite and repost about laser speed and power and factors affect laser performance in a bit)

Edited January 11, 2019 by garyo1954
correct misspelling

[LatigoAmigo]

1 hour ago, garyo1954 said:

It's a misthought

I completely understand. Mine is a homemade laser (not by me), and I always wonder if it is performing at its best. Thanks for the clarification.

[garyo1954]

4 hours ago, LatigoAmigo said:

I completely understand. Mine is a homemade laser (not by me), and I always wonder if it is performing at its best. Thanks for the clarification.

LatigoAmigo, Nothing wrong with a homemade laser. My first CNC was home built as well, and I learned more during the build then any amount of book teaching available. Nothing comes close to learning by doing.

Great leather work as well. I love the look of it! Wish I could show work half that nice!
Just amazes me to see it!

As far as 75% power, that's out of my league. I'd much prefer to do multiple passes. There are plenty of laser guides online that offer predetermined setting, but those setting are compiled in a controlled environment, with set temperature, well aligned machine and well controlled variables. They don't/can't cover all possible situations. Setting for someone in Texas may bomb used by another in the UK. This is the main reason I've found for the hesitancy of sharing setting from one machine to the next. Different lenses, different mirrors, even different water temperatures can make a difference in laser performance.

So anytime someone experiences poor performance/drop in performance the first thing pointed to is to clean the mirrors and lens. Smoke residue can build up occluding the beam. Look for spots, dots, streaks, discoloration and possible cracks or breaks in the mirrors and lens.

Then check the alignment of the beam to ensure it is hitting the center of each mirror.

And check the alignment of the gantry to ensure it is straight and level.

Focal point of the lens is also important. You can buy a lens with a different focal points depending on the job. A 1.5" lens (38.1mm focal point) will have a smaller beam width allowing for greater detail but less focal range tolerance meaning less leeway as to the focus point. It has a poor cutting ability limiting the cuts to about 5mm at best.

A 2" lens (50.8mm focal point) is a good overall lens allowing for good detail with a better tolerance in focal range. The tolerance range of a 2" lens will allow for engraving curved surfaces without a rotary in a limited space (33-37mm). The cutting ability approaches 1/2" depending on material to be cut.

With a 50.8mm lens the focal point should be adjusted to the job. For an engrave the lens should be approximately 50.8mm above the material surface.

When cutting, the focal point can be adjusted to cut at any depth or completely through the material by adjusting the height of the material to the lens. To cut through a 3mm material one should subtract the thickness of the material from the focal point. For example, with a 50.8mm focal point lens, subtract 3mm from 50.8, leaving 47.8mm. 47.8mm is then the height the surface of the material is from the lens. A word of caution: The closer (or farther) you get to and from the lens the greater the divergence of the beam becomes. In some cases multiple passes is the best option.

Ambient temperature is something we can't control. Many have noted that certain chillers will bring the water only to the ambient room temperature which is not hardly ever optimum. For stable laser operation/optimum performance water temperature is said to be +/- 1 or 2 degrees between 17 - 19C for 50mm to 60mm tubes and 20-24C for 80mm to 90 mm tubes. Once above 24 centigrade you're losing tube life.

If the temperature is getting high, drop a frozen half gallon bottle of water in the reservoir. Or put one in 15 minutes prior to starting the job allowing time for the cooler water to circulate and preventing a shock to the system which could crack the tube. (When adding a frozen bottle consider turning the machine off for 15 to 20 minutes.)

Air assist helps in blowing smoke and bits away from the lens and work area and preventing flares-ups (which could turn into fires).

Power and speed are different settings yet they work together to perform a given task. In most cases power and speed are set inversely. Cutting a hard material requires a higher power and lower speed while engraving a glass Christmas ornament requires low power and high speed.

Tips for laser leather?

1. Wet leather, not soaking, cuts/engraves easier. But wet leather also curls more when as it dries which will cause straight lines to squiggle.
2. Use painters tape/masking tape or paper based tape over the area you area you plan to work. Not only will it help prevent smoke/soot for settling on the surface it allows for cleaner edges. Some people tape both sides their leather. I tend to use a strip of double sided tape on the bottom to help prevent curling.
3. Tape is also good for creating a contrast in dark leather which will not produce a good contrast. Once you've done your engrave you can then rub a wax based colored fill (or even spray it) to produce a foil effect. Once the color is dry you simply peel off the tape. Here's a couple I tried. You can see that weeding the smal bits f tape doesn't work out as I thought, but it gives you an idea what can be done.




4. Another good thing using tape. You can use very low power and high speeds to do a test run without marking the actual leather.
5. Only engrave leather once. Even if the engrave looks like it can be darker, its more likely you'll ruin the piece by burning through than deepening the color.
6. Although I haven't tried it, some prefer to cut leather flesh side up. They say by cutting it upside down they are able to retain a crisper edge on the surface.
7. For cleaning I was originally using Leather CPR which worked great on most leather. Then I ran across a couple of pieces where it faded the engrave terribly. Since then I use Fiebings 4 Way Care. I've also seen people who get great results with a soft toothbrush and plain water.

I'm sure there are more. Just as there is way more about laser than can be put in one post.
But this is getting too long so it's time to stop. Until later.

 

[LatigoAmigo]

4 hours ago, garyo1954 said:

I'm sure there are more. Just as there is way more about laser than can be put in one post.

You have provided quite a lesson on laser cutters/engravers. Wow. Maybe you could put it into a document that people could download. This information is not readily available, and can easily get lost in the abyss of postings here on the website.

[garyo1954]

23 hours ago, LatigoAmigo said:

You have provided quite a lesson on laser cutters/engravers. Wow. Maybe you could put it into a document that people could download. This information is not readily available, and can easily get lost in the abyss of postings here on the website.

Took a lot of work, reading forums, making mistakes, and making more mistakes to learn some of that. Being a member of a couple of laser pages on FB where they do nothing but diagnose laser problems and talk about how to do things helps a lot. 

Started a new wallet. Not sure I can bevel it like I wanted. I may try just to to see what happens. Thinking to use the black for the inside......

We shall see how it goes. (Don't expect much since this is wallet #1)

 

[chrisash]

Like the fine engraving , but the font design style is poor with the link between the r and Y

[Mark842]

Thank you to everyone contributing info on this. I'm looking to purchase something this year. Ran into a local Epilog rep a few days ago and he invited us to their shop to do some testing. We are hoping to go get some laser time on our leathers with him sometime next week. I'm more interested in engraving than cutting as we have clicker dies for most of our products already but I had never thought about using a laser to cut our own packaging. We have several products that are problematic when it comes to packaging and making our own could be the ticket!

[garyo1954]

9 hours ago, chrisash said:

Like the fine engraving , but the font design style is poor with the link between the r and Y

chrisash, good point. If/when (and you know I will) do it again, I'll likely use the initial G. Maybe circle G and bevel it. After using block fonts a thousand times it was  nice to see something different for Christmas. Script is, IMO, a more personalized touch. Nonetheless a block  font would  or just an initial would work better for this application.

Thanks!

[garyo1954]

3 hours ago, Mark842 said:

Thank you to everyone contributing info on this. I'm looking to purchase something this year. Ran into a local Epilog rep a few days ago and he invited us to their shop to do some testing. We are hoping to go get some laser time on our leathers with him sometime next week. I'm more interested in engraving than cutting as we have clicker dies for most of our products already but I had never thought about using a laser to cut our own packaging. We have several products that are problematic when it comes to packaging and making our own could be the ticket!

Great! If you haven't already, check out the Epilog site. A ton of information there with downloadable samples you'll be interested in.

[RockyAussie]

Sorry guys. I have been in this all weekend and with the fitting of all the T nuts in place and drilling the holes,sanding and polishing the acrylic edges,wiring in external switches, fitting the suction motor and more shelves along with taking pictures and videos of the testing I just ran out of time. For now here's a couple of pictures of where I am up to. Good news is that it all works and well and the video of the testing looks good. I just have to find some time to do the video editing and uploads now.

This first one shows where I am applying the foam around 3 sides to direct the air flow. The video will show that later.

Will get more of the building progress pictures through later this week along with the videos.

[dikman]

Brian, mate, you've definitely got some hidden geeky nerd in you!