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View Full Version : Precise location engraving on Yeti with rotary?



Brent Franker
09-10-2016, 2:37 PM
Hey Guys!

Just curious if you might have any tips for the best way to put an engraving exactly where you want it on a Yeti tumber using an Epilog rotary device? I don't do much of this and did some Yeti marking last night and the first one I didn't get centered very well. The rest were OK but were more guesses, based on how far the first one was off, than anything precise. LOL

I'm trying to center a graphic in relation to the Yeti or Ozark (Wal-Mart brand) logo on the 30oz tumblers. The first one I tried I did it like this... logo on cup is 2" wide. Graphic is 3.5" wide. That makes for 0.75" that the graphic should hang over each side of the 2" logo. Simple enough I thought... turned x/y OFF. Moved head down to bottom of tumbler where logo is located. Measured and made sure the tumbler was rotated 0.75" around from the right edge of the logo to the red dot. Put home position back to normal. Placed graphic at the top of the page so it would start engraving immediately without rotating the tumbler. In concept, I thought this was right (regardless of the diameter of the top portion of the tumbler as compared to the smaller diameter where the logo is) but turned out to not even be close to being accurate. After thinking about it (after it didn't work!), yeah, measuring 0.75" with a flexible tape on the smaller portion WOULD rotate the top portion of the tumbler noticeably more.

Since there are so many variables here to get it right, just curious how you experts have found the best way to locate your piece when using a rotary. I could do a ratio of the top diameter to the diameter where the logo is and do something with that. Or maybe do a center type engraving where I just put the logo facing directly UP (which still involves measuring).

Anyway, it'll be a bit before I can play around with this again (work getting in the way of my laser playing!) but wondering if you guys had any recommendations?

Oh, also on a different note but related to the Yeti marking... I'm using a Cermark knockoff and it does fairly well. However, at some angles the marking looks nice and black but then hold it at a different angle and light and the marking lightens up a bit and looks duller or with a hint of dark purple. Do you think this is because it's a cheaper Cermark version or are those results indicative of not enough or too much power? I'm running my 75watt Epilog at 100% power and 50% speed for this. I'll do a test with color mapping but in the meantime just wondering if you guys with a lot of experience recognize that condition as anything obvious I'm doing wrong.

Thanks much!

Kev Williams
09-10-2016, 2:57 PM
I have a 'good' rotary with a chuck. Not sure if the hotdog turners work the same, but lets assume so...

A Yeti tumbler in the middle measures 3.13" diameter. X pi = 9.833". This is the working area height. I use a default of 18" long as my default 'rotary' working area length.

So open a window in Corel and make it 18" x 9.833 inches.

Half of 9.833 is 4.916 inches, so put a horizontal guideline there.

Half of 4.916 is 2.458 inches. Put additional guidelines that far above and below the center guideline.

The top and bottom of the working window is the "zero" point. The guidelines split the circumference of the yeti into quarters.

Assuming your laser considers the zero point the first place it starts engraving, then positioning your graphics should be easy-
The trick is to figure out what you actually want at the zero position. When I do these, I put the Yeti logo straight up
(90% of the time visual alignment is fine), and what I'm engraving goes on the centerline exactly half way around.

When doing coffee cups I put the handle straight up, then the engraving goes on the appropriate quartered guideline,
which puts it exactly halfway between the handle and the the 180 point...

Hope this helps some... ;)


As for your Cermark knockoff, what is it? Cermark changes its 'look' at different lighting angles too...

Brent Franker
09-10-2016, 5:12 PM
I have a 'good' rotary with a chuck. Not sure if the hotdog turners work the same, but lets assume so...

A Yeti tumbler in the middle measures 3.13" diameter. X pi = 9.833". This is the working area height. I use a default of 18" long as my default 'rotary' working area length.

So open a window in Corel and make it 18" x 9.833 inches.

Half of 9.833 is 4.916 inches, so put a horizontal guideline there.

Half of 4.916 is 2.458 inches. Put additional guidelines that far above and below the center guideline.

The top and bottom of the working window is the "zero" point. The guidelines split the circumference of the yeti into quarters.

Assuming your laser considers the zero point the first place it starts engraving, then positioning your graphics should be easy-
The trick is to figure out what you actually want at the zero position. When I do these, I put the Yeti logo straight up
(90% of the time visual alignment is fine), and what I'm engraving goes on the centerline exactly half way around.

When doing coffee cups I put the handle straight up, then the engraving goes on the appropriate quartered guideline,
which puts it exactly halfway between the handle and the the 180 point...

Hope this helps some... ;)


As for your Cermark knockoff, what is it? Cermark changes its 'look' at different lighting angles too...

Thanks, Kev!

I do follow exactly what you are saying and actually have my "page size" laid out like that. Only real difference I think is that with my hotdog turner (LOL!) it spins the Yeti at the very top so that is where I take the measurement for the page size.

I did pretty much exactly what you describe for laying out my page when I did my first Yeti and marked something on both sides of the Yeti... but mostly "estimated" where to rotate the Yeti in relation to the logo. The problem for me and what I was trying to do was put the graphic centered directly ABOVE the Yeti logo whereas you are putting your graphics so the Yeti logo is centered on the other side of the cup. I could do this with a cup with a graphic on the back just like you because the graphic would be entirely contained on the page in Corel. However, if I want to put the graphic centered above the logo and do the easy thing of just eyeballing the Yeti logo directly straight up, my graphic ends up being half off the top of my page. But... hmm... I could add an additional step (far easier than calculating everything each time and measuring) and simply put a piece of tape on the bottom of the cup and mark the center of the BACK side of the Yeti. Align this 180 out mark straight up and place the graphic on the quartered out page accordingly. That would keep the entire graphic on the page. I'm thinking this would be easier than measuring and calculating :)

As for the product, I bought it a few years ago off eBay. Was less than $30 for 4oz. It was from Color Laser Productions. Bit bummed because it appears as though they are non longer in business. When I did a search, a thread here came up http://www.sawmillcreek.org/archive/index.php/t-180354.html I've got some pics at home of the results of a finished Yeti cup and I was pretty happy with it. Did it last Christmas and the guy uses it daily and it still looks great. I did try the dry moly last night ( this one https://www.amazon.com/gp/product/B0013J62P4/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1 ) and it was a miserable failure. I tried a color mapping test at 50% speed starting at 10% power going to 100% in 10% steps and every marking rubbed off easily with a washcloth. GRRRR. I did some reading here and saw that this stuff might take considerably more power than Cermark or the stuff I'm using? Might need to go to like 100% power and 10% speed or something? I don't know but a lot of people seemed to praise this stuff I got on Amazon but it didn't work at all for me! :)

Kev Williams
09-10-2016, 11:01 PM
Ok, so we're on the same page--

I'm assuming YES to this, but going to ask anyway--do you have a red pointer, AND can you display your laser's current coordiates, either on the machine display, or in the software?

-- I live and die by these coordinates...

I use the pointer to locate the top and bottom of whatever I'm engraving. Example, what I consider the top of a Yeti as being held in my machine is usually about 1/2" or so from 'zero-left', as found by the red dot. Then I find the bottom. Then I put guidelines at these points. Next, use the machine to slew the gantry (X) and rotate the part (Y) to find the location of an existing logo (like the Hydroflask logo f'rinstance). I find the top, bottom, left and right edges of it, write down the coordinates, then make a box on the screen to match them. Yes it's time consuming, but takes less time (and money) than do-overs! :)

Now everything you need to know is on the screen, and you can move whatever you want to engrave relative to your coordinates. Just make sure nothing extends above or below the working area. If it does, then you'll need come up with a new straight-up 'zero point'.

I brought up Hydroflasks because ironically, I'm setting up a job of those right now, and my customer changed her logo, added more text. Now I have to see if I can still engrave them without removing the paper strip they glue on around the bottom. I'll be using the red dot to find the top edge of the strip and the top of the bottle, and HOPE the new logo fits above the strip without having to move the logo up the bottle too far. If it ends up not looking right, I'll be pulling the strips off all the bottles first (which I'd rather not do!)

To set these up, I put the Hydroflask guy straight up, that's my zero-point, and the customer logo will be 180 around on the other side.

Finally-- you can 'test drive' your Cermark (or whatever yours is) by simply engraving it fast (say, 80% on your Epi), at very low power (4 or 5%) and at reduced resolution (like 200dpi, just to speed up the test process).

Find a power setting just high enough that it goes dark enough to see what you're engraving. You'll have an visual you can look at and measure to see if it's right. And it won't EVEN stick to the metal at those settings...

Steve Clarkson
09-11-2016, 8:03 AM
Personally, I prefer a searing hot metal poker in the eye over using my Epilog rotary.

Try putting a hairline rectangle around your graphic.......then with the red pointer on, "vector cut" the rectangle (with the lid open so the laser doesn't fire) at like 10 speed......see where it is hitting the yeti, then pause it and rotate the yeti until the red dot is hitting exactly where you want it to. Then reset. About 4 out of 10 times it should rotate back to the correct position.

Mike Null
09-11-2016, 9:03 AM
I would make the following recommendations: 1. use Cermark, the other stuff is too unpredictable. There's a reason they're not still in business. 2. Place your image on the opposite side from the logo. There is no reason to believe that the cup maker's logo should be the centerpoint of your work.

On my Trotec I use the red dot pointer as my center point and move my art to that.

Brent Franker
09-11-2016, 2:07 PM
Ok, so we're on the same page--

I'm assuming YES to this, but going to ask anyway--do you have a red pointer, AND can you display your laser's current coordiates, either on the machine display, or in the software?

-- I live and die by these coordinates...

I use the pointer to locate the top and bottom of whatever I'm engraving. Example, what I consider the top of a Yeti as being held in my machine is usually about 1/2" or so from 'zero-left', as found by the red dot. Then I find the bottom. Then I put guidelines at these points. Next, use the machine to slew the gantry (X) and rotate the part (Y) to find the location of an existing logo (like the Hydroflask logo f'rinstance). I find the top, bottom, left and right edges of it, write down the coordinates, then make a box on the screen to match them. Yes it's time consuming, but takes less time (and money) than do-overs! :)

Now everything you need to know is on the screen, and you can move whatever you want to engrave relative to your coordinates. Just make sure nothing extends above or below the working area. If it does, then you'll need come up with a new straight-up 'zero point'.

I brought up Hydroflasks because ironically, I'm setting up a job of those right now, and my customer changed her logo, added more text. Now I have to see if I can still engrave them without removing the paper strip they glue on around the bottom. I'll be using the red dot to find the top edge of the strip and the top of the bottle, and HOPE the new logo fits above the strip without having to move the logo up the bottle too far. If it ends up not looking right, I'll be pulling the strips off all the bottles first (which I'd rather not do!)

To set these up, I put the Hydroflask guy straight up, that's my zero-point, and the customer logo will be 180 around on the other side.

Finally-- you can 'test drive' your Cermark (or whatever yours is) by simply engraving it fast (say, 80% on your Epi), at very low power (4 or 5%) and at reduced resolution (like 200dpi, just to speed up the test process).

Find a power setting just high enough that it goes dark enough to see what you're engraving. You'll have an visual you can look at and measure to see if it's right. And it won't EVEN stick to the metal at those settings...

Yes, using a red pointer. I know the laser displays current coordinates with the regular engraving but not so sure about with the rotary connected. I wasn't paying a lot of attention when I turned x/y OFF to position the red pointer but thought there were coordinates there even with the rotary attached. If so, the X would probably work OK but I don't see the Y working too well with the hotdog roller! Maybe though... will keep this in mind for sure :)

Excellent recommendation on the low power high speed just to see what it's going to do. Thanks!!!

Brent Franker
09-11-2016, 2:10 PM
Personally, I prefer a searing hot metal poker in the eye over using my Epilog rotary.

Try putting a hairline rectangle around your graphic.......then with the red pointer on, "vector cut" the rectangle (with the lid open so the laser doesn't fire) at like 10 speed......see where it is hitting the yeti, then pause it and rotate the yeti until the red dot is hitting exactly where you want it to. Then reset. About 4 out of 10 times it should rotate back to the correct position.

LOL! I've not used the rotary much at all but so far no problems with the handful of Yeti's I've done. I've had some slipping on odd shapped glasses or mugs so do know what you mean as it's definitely not the perfect tool :)

4 out of 10 to go back to the original start? Not much point in precision location with those kinds of odds. LOL!

Thanks for the recommendation with the rectangle!

Brent Franker
09-11-2016, 2:14 PM
I would make the following recommendations: 1. use Cermark, the other stuff is too unpredictable. There's a reason they're not still in business. 2. Place your image on the opposite side from the logo. There is no reason to believe that the cup maker's logo should be the centerpoint of your work.

On my Trotec I use the red dot pointer as my center point and move my art to that.

1) Gotcha. I'm going to get some Cermark and give it a go.
2) I agree. I was just trying to place the graphic on the tumbler so it looked "organized" and not just thrown on there anywhere. But, you're right... I don't care if or need the logo to be a centerpoint and as talked about above... WAY easier to just eyeball the logo straight UP and go from there.

Thanks!

Brent Franker
09-11-2016, 3:10 PM
1. use Cermark, the other stuff is too unpredictable. There's a reason they're not still in business.

Do you or anybody else have a favorite place to buy Cermark from for the best price/service? And is the spray can method or brushing method the best value? The generic stuff I have right now is a brush on and there seems to be a lot of waste! :)

Thanks!

Kev Williams
09-11-2016, 3:28 PM
I've bought from both Laserbits and Engravers network, both via ebay, prices are pretty much the same...

Cermark thins with denatured alky. The waste involved is simply the part the doesn't get engraved. Think of Cermark as vinyl signage. More vinyl goes into the garbage than goes into the sign...

I have a bottle of premixed Ceramark and a bottle of alky that I rinse my brushes in. Half the time I don't bother rinsing the brush until I'm about to use it the next time...
The rinse-alky is what I use to thin the Cermark. No waste.

I thought airbrush spraying was fantastic once trying it after using cans, but since using brushes, I don't bother spraying anymore. I used to go thru almost 2 airbrush bottles worth on a 24 x 32" stainless panel. Brushing the same panel uses not quite ONE bottle's worth. A 50% savings works for me, as do brushes in general, they're much less finicky than an airbrush! ;)

Brent Franker
09-11-2016, 4:19 PM
Dang, I would have thought brushing would have been more wasteful. And what I meant by brushing seemed wasteful was that, at least when brushing this very thin stuff on the curved Yeti tumblers, a bunch of it would run over to the "back" of the tumbler (gravity is a funny thing LOL). Also, what didn't help was I only eyeballed how much I needed to apply so of course used way more than needed to ensure I had covered enough. This stuff is expensive enough I should probably take a little more time and not brush on as much excess. The same is true for the spray though if not exactly sure how much area the graphic is going to cover, extra is required. Doing this as a beginner on the curved/round Yeti cup as opposed to a flat surface, which is easily measurable, doesn't help either! :)

Also, in looking at the prices between the spray can and stuff you add denatured alcohol to, when accounting for adding the denatured alcohol, they look to be very close in price when comparing overall product.

As for airbrushing it, yeah, that's probably not for me the every so often laser user who does a few things here and there. LOL

Thanks again for the assistance!

Mike Null
09-11-2016, 5:11 PM
Brent

Many make the comment that Cermark is expensive. Once you begin doing some volume numbers you will realize that Cermark is one of the cheapest but most profitable materials you can use. I typically get $2500 to $4000 out of a 250 gram bottle that costs $129. I can see jobs that might produce less than that but not much.

For most of my work I use a foam brush. If the air brush weren't such a nuisance I would use it more frequently, especially on large orders of Yetis.

Brent Franker
09-11-2016, 5:18 PM
Yes, that is a good point when looking at what you get out of it. I primarily do vinyl stuff and only small graphics. I use the high quality vinyl which is 3 times more expensive than cheap "sign vinyl" but since all my graphics are pretty small, that cost difference is pretty much irrelevant.

Thanks for the foam brush tip! I did notice that the regular brush that came with my generic stuff (came built into the cap) tends to leave streaks which makes me go over the same spot again sometimes using more product than I need to since I'm double coating most of it.

Thanks!

Kev Williams
09-11-2016, 8:01 PM
Foam brushes are great! A 2" brush loaded up, I can sometimes cover almost a square foot before a reload. 1" brushes are great for 1-shot coverage of 1x3 plates and such, several plates on one load is easy-

BUT- foam brushes don't last long, the alky's hard on them. And getting the excess out can be a messy pain.

Unless I'm doing really big things, these are the dirt-cheap dollar store artists brushes I use. The bristles are a bit coarse and loose-fitting, probably not all that great for painting, but they're perfect for Cermark! They hold quite a bit, and they put down a pretty smooth swath. You can see from the 2 used brushes that I just set them aside when done, and soften them up with alky before using them the next time. Occasionally they need a good cleaning, and these 2 used ones are about due. (they tend to streak when they need cleaning). I rinse the cermark out as much out as possible in the alky bottle, then take a toothbrush and warm water to them and let them dry. Hard to wear these out, and they seem to work better the older they get! ;)
343939

Brent Franker
09-12-2016, 9:58 AM
Excellent! We've got a few dollar stores around here. I'll check that out. I'm going to be a pro in no time with all this excellent advice and help! Thanks guys :)