Cermark and Aluminum

[Chuck Stone]

I'm having trouble getting Cermark to stick on aluminum (6063) I've tried
both satin finish (sanded to 600) and polished to a mirror shine. Cleaned
with denatured alcohol, acetone, degreaser .. you name it. Those things
don't seem to make a difference as long as the metal is clean. DNA was
the final wash.

Always done at 100% power, 30W laser at 10%, 5%, 1% and finally two
passes at 0.1% ! (344 minutes to laser this pen!) This time the Cermark
is sticking enough for me to handle it gently until I can get some sort of
a finish on it. (this one is finished with CA and polished with micromesh)
and I'll probably cast others in resin. But this would never hold up to the
wear and tear of putting it in your pocket two or three times.

I've ordered the LMM14 to see if it works any better than the LMM6000,
but can anyone share any 'secrets' other than what I find in the
search function? I'll wash your car.. :p

[Dee Gallo]

Chuck, that's a beauty! Sorry to hear it was such a bear.

So is the issue with aluminum that the metal does not hold heat enough? So the thinner pieces like your pen would be the hardest to do? If that's the case, could you put a warm metal rod into the barrel to help as a heat sink? Or fill it with lead shot? Just thinking out loud.

I don't have enough experience with Cermark to help you, but would love to know the answer too. Hopefully someone with good skills will post a miracle answer.

Meanwhile, I love your work. I use your pen every day... it's great!

:) dee

[Chuck Stone]

LOL .. you rub Spock's head for luck, right?

I'm not sure why the problem. I know some others are able to do aluminum
but I can only make temporary marks so far. I took your advice on the
airbrush and that makes application easier and more consistent. We'll see
when the 14 gets here..

Thanks for the flattering comments. You're now in my will :p

[Dan Hintz]

Coooooool!!!

10S should be about right for you... going too slow (e.g., 1S) ca burn it right off. Did you cut the aluminum, or did you buy the barrel? You mentioned sanding, I was just wondering if you were getting through any clear coat that might be on a purchased barrel.

[Bob Argus]

We recently had a need to attempt to use Cermark on aluminum. tried the liquid LMM-6000 with no success. Called Ferro Corporation for advice. We were told that a better product to use on most aluminums is the LMM-6018 Black Laser Marking Tape. The tape formulation worked perfectly.

[Chuck Stone]

There's no clear coat, this was a piece of lightning rod. Drilled and bored it
out on the lathe and then turned the outside to the final dimensions. Then
sprayed and lasered.
I tried going down in speed from until I finally ended up at 0.1% and that's
just around 1 inch per second. Two passes and this is the closest it has
come to sticking.

I don't think the tape would work for me here .. this is lasered 360 degrees
around the barrel, so I couldn't have a seam showing anywhere .But some
of the other patterns could be re-arranged to hide a seam..
Maybe I should make that my next experiment..

[Viktor Voroncov]

Hi, Chuck
344 minutes for this beauty - it's fine! Congratulations!

[Bill Jermyn]

For 1/8" aluminum (usually satin finish) I use 20 speed, 100% power, 600dpi on my Epilog Legend 32EX 75 Watt. I use the LMM 6000

You say the cermark is "sticking enough for me to handle it gently". I think that's your problem, the bond should be better than that.

The best degreaser I've found is Mr. Clean. Spray, rub, rinse, dry, repeat. When it squeaks under your finger, it's clean.

I've cermarked aluminum sucessfully that came out of a filthy machine shop, and had been cut with coolant (then allowed to sit to long enough to gather a good coating of crud). Worked perfectly.

[Scott Shepherd]

I do aluminum pieces for a company about every other month and I'm still just using the spray can. It works very well on the aluminum. Not the most economical solution, I know, but it works.

[Chuck Stone]

You say the cermark is "sticking enough for me to handle it gently". I think that's your problem, the bond should be better than that.

I know! I've tried various degreasers at different times, and so far the one
that seems to work best is Incredible Pink. I do get the squeaky clean
surface with most everything, but the Pink works best at removing the
cutting oil I use on the metal. The auto salvage yard even uses it on the
engine parts they pull out of cars before they put it in a big washer with
hot water. I don't think the cleaning is the issue, but I can certainly try
out other things..

When I say 'enough for me to handle gently' I mean AFTER marking. The
black marks seem pretty fragile.
I'm lasering at 1000dpi, 100ppi, 100% power and around 1 inch per second.
The Cermark comes out a lovely blue before I was it gently with a paint
brush and Simple Green. (sort of like an archaeologist on a dig :p )

[Dan Hintz]

Chuck,

The blue color tells me you're most likely overpowering it. Drop back to 500dpi (or thereabout) and run it at 100P/10S. I made the same mistake when I first started with Cermark after seeing so many posts about how much power it took... once I dropped back to 500dpi and stopped cooking it, I found dialing it in much easier.

Let us know what you come up with...

[Chuck Stone]

I can try it again, but I know that 10% speed at 500dpi is one of the
settings I've tried. It marked well enough, but would rub off easily..
Someone else recommended bumping it up to 1000dpi and it is
sticking better, but still not what I'd consider acceptable.

I wonder about a different type of aluminum? :confused:

[Gary Hair]

Chuck,
I would send a piece to Ferro and let them test it for you. As long as the settings are right and the Cermark is sprayed on correctly, it should stick to aluminum. Dan is right about overpowering it, you want a black mark, not tan or beige or blue, just black. One thing to try would be to take a piece of the rod and file a nice smooth flat on one side, don't bore it out, and spray and laser it. Laser 1/8" squares at 100% power and 1% to 10% speed and see what happens. Stick with 1000 dpi and max PPI.

Good luck!

Gary

[Chuck Stone]

I'll have to try that tomorrow. I did some testing and it just won't stick
well below 0.1% and even then it still takes two passes to stick enough
to handle it. One pass and it will come off with a small paint brush and
water. Here's a pic of the blue color..

[Gary Hair]

Chuck,
Can you take a picture of the piece coated with Cermark? I have a feeling you are putting it on way too thick and that's why it takes so much power, turns blue and doesn't stick. Make sure you thin it to the consistency of nonfat milk and spray it on so thin that you can still see the metal through the coating. Start with such a thin coating that you think it can't possibly work and then make the next one thinner... you'll be surprised!

Gary

[Chuck Stone]

I'll try that, too .. I sprayed it so it barely covered the metal, and in some
places you could still see the silver color through the Cermark. I didn't thin
it quite as far as skim milk, but thin enough that I was sure it wouldn't work.
It looked like a watercolor wash.

On another note.. I coated one with CA and one with NC lacquer and put
them on the front seat of the car for two days. The lacquer one is faded
on one side. Don't know if that is related to the lacquer or if the settings
were different (I'll have to look up the numbers) but it was an interesting
change. No chance so far on the CA. Still have to try it with polyester
resin too.

[Dee Gallo]

My inclination is to think you have it on too thin. I did an experiment with cermark spraying it across one piece from very thick to very thin. The very thick did alright, but the color was weak. The very thin blew right off the metal and left silver. Obviously the middle ground was the best, sort of like the 3 Bears... just right!

Keep us posted, this is interesting!

:) dee

[Chuck Stone]

Here's one ready to go..

[Scott Shepherd]

Looks thick to me, but it might be the photo.

[Sara Gould]

I wonder about a different type of aluminum? :confused:

It is really confusing, agreed.

I got LMM6000 to stick to a thin aluminum flashing shingle (5x7) but had no luck at all with bare copper, which it is supposed to mark.

Your pen is gorgeous though! I hope you get it. Could you machine stainless steel instead?

[Dan Hintz]

Chuck,

Basic Cermark is not the easiest to photograph, but that definitely looks too thick... as Dee said, that explains why you need so much power.

[Chuck Stone]

I can't machine stainless myself .. not without buying another lathe.
(what? more new tools?? COOL!! :D )
The aluminum can be done on a wood lathe and is light enough for a pen.

I know the cermark looks thick in the photo, but believe me .. you can
still see a slight reflection through it in places. It is as thin as it can be
and still be considered coverage. If it were painted, you'd be looking for
one more coat. If it were sprayed on glass, you could probably see through
it.

I think I just need to find someone with a more robust laser and give them
the patterns

[Gary Hair]

I know the cermark looks thick in the photo, but believe me .. you can
still see a slight reflection through it in places. It is as thin as it can be
and still be considered coverage.

Chuck,
You may be able to see metal through the Cermark, but it's too thick, actually, it's not thinned enough. I know that sounds the same but it's not. It looks like stucco on a wall and it should look a lot smoother than that. It's hard to describe in writing, but that looks like it "splattered" a thick mixture instead of "sprayed" a liquid on to the metal.

I wish I had a digital video recorder so that I could show you how thin mine is and what it looks like while spraying and after it's sprayed.

Trust me - thin your mixture down with 50% DNA and 50% of the mix you have now. Try just a little bit, about 1/2 of your airbrush jar should be fine, an ounce or so. Adjust the airbrush so that it is just a mist coming out and spray on one single, very thin, coat. If it still comes out looking like your photo then there is something else that I'm missing.

I have done literally thousands of stainless steel parts and you would be amazed at how little Cermark it actually takes to make a mark. I haven't done near as much aluminum but what I have done seemed to take the same amount of Cermark as the stainless, just slower speed. With my 30 watt machine I use about 15% speed (of 80ips) for stainless and about 5% for aluminum - depending on the thickness and finish.

Thin, thin and thin again...

Gary

[Mike Null]

I agree with Gary. I don't measure my mix but I thin it more than 3 parts DNA to 1 part Cermark.

[Chuck Stone]

I thinned it 1:1 with DNA and then thinned THAT 1:1 with DNA again, so
I'm at about 3:1 now. The 'splatter' you see is when it 'sputters' coming
out of the airbrush. No matter how much I shake it, it doesn't seem to
even out more than that.

I know what you mean about the difference between a thick coating and
a thick consistency. The coating is as thin as I can spray it, and if I thin
the consistency any more it simply flows off of the metal.

The LMM14 should be here this afternoon.. we'll see if that makes a
difference. Fingers crossed .. I really want to do more of these pens
(and people want to order them!)

Thanks for the suggestions, I'll keep you updated

[Chuck Stone]

Well .. the LMM14 got here, but it was the spray. They sent a call tag
and shipped the paste. That stuff doesn't stay on for anything! I think
you can wipe it off with a psychic nod.

Same deal, tried different thicknesses with the same results. It looks
good when you're done, but even a small artist's paint brush is all it
takes to pull off the marking.

30W laser, 100% power, anywhere from 30% to 0.1%. This didn't turn
blue, it goes on dark gray and turns white/tan/yellow. Still comes off.

I can't afford any more of this stuff!

[Dan Hintz]

Chuck,

If you'd like, send me a pen and I'll try a sample in my machine, make sure it's not the pen...

[Dee Gallo]

Chuck, have you tried any of the various Cermarks you have on a plain flat piece of metal to narrow the problem down to EITHER the Cermark OR the metal?

I have not found Cermark to be that finicky at all, even if it gives you poor results, at least you should be getting something better than wipe off powder.

cheers, dee

[Chuck Stone]

Dee .. I haven't done that yet.. it's on my list, but I am on the last
piece of material in my stock right now. (have wiped it off and redone it
a few times) but might be picking up more this afternoon. I'll try a flat
spot.

Dan.. that's a generous offer. Should I mark it first so you can see
how thick/thin I am putting it on? Should I send the file and settings?

Have a regional penturner's meeting today, so I'm packing up to go there.
Someone is (hopefully) bringing some drilled/turned tubes to the meeting.

I just need it to stay on long enough to get a topcoat of either CA or
polyester resin

[Dan Hintz]

Chuck,

If you can get it here without the Cermark wiping off (not an easy task), that would be best... I could tell right off if you're putting it on too thick. Otherwise, I'd still be able to test if it's the item itself causing the issue.

[Mike Christen]

Hi Chuck

Have you tried using 6061 aluminum? I make a lot of motorcycle parts using 6061, occasionally I mark it with thermark and it works great and is very durable. I would think 6061 could be machined the way your doing it now.

[Chuck Stone]

I haven't tried the 6061 yet. I tried the 6063 because it was here. :p

I was going to pick up more today, but they're not cut/drilled out yet so
I'll probably get it later in the week. I think one piece was 6061 and the
other was something like 4711? (I don't know aluminum) I'm told they will
both cut/turn with woodturning tools, so that was my main concern.

I still have the last 6063 tube, it's been sprayed and marked many times.
(with both LMM14 and LMM6000) but it's clean now. I'll spray it again and
wrap carefully and get it to Dan this week. At least I'll know if it is the
material or something I'm doing wrong.

[Mike Christen]

6063 is softer aluminum and usually extruded, the type of shapes you would find in home depot. It does not mill very good, gets gummy. 6061 is much harder and mills very nice. Maybe the 6063 being soft is dissipating the heat faster causing the problems, not sure though, I'm no expert, but I know i was able to mark 6061 without a problem. Hopefully Dan can give you a answer.

[Uma Duffy]

FWIW we just tried the Cermatk tape and it has worked perfectly each time we've used it, unlike the spray or mix it Cermark. We never got reliable enough results that I'd be tempted to take a big order using the spray. We must never have perfected the art of applying just the right amount and the tape handles that problem nicely. But it's definitely pricey and doesn't come in enough widths for every kind of job...but for a pen or a flashlite...PERFECTO!

[Chuck Stone]

But it's definitely pricey and doesn't come in enough widths for every kind of job...but for a pen or a flashlite...PERFECTO!

If I were simply engraving a few lines on a pen, that would work. But I'm
doing a 360 degree pattern, so any sort of seam would ruin the effect.
Might be worth having some on hand for other projects, though.. :D