Author Topic: LED Bulbs Already Failing  (Read 38220 times)

Offline jvanick

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Re: LED Bulbs Already Failing
« Reply #120 on: February 24, 2016, 02:25:54 PM »
I have one of those...

When exposing for best resolution,  I was FAR under cured.

And then delamination!

Resolution excellence is nothing if it all falls off at 10 impressions!

Mesh count and thread thickness also play a part in useable resolution, you have to have threads to hold the dots in place and the emulsion stencil has to survive the required number of impressions or... well fail and that costs money.
10... try 2 lol.  We could hear it failing on the first print.

You havent lived until you hear the emulsion crackling with the squeegee stroke.


Offline DouglasGrigar

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Re: LED Bulbs Already Failing
« Reply #121 on: February 24, 2016, 02:33:56 PM »
I have one of those...

When exposing for best resolution,  I was FAR under cured.

And then delamination!

Resolution excellence is nothing if it all falls off at 10 impressions!

Mesh count and thread thickness also play a part in useable resolution, you have to have threads to hold the dots in place and the emulsion stencil has to survive the required number of impressions or... well fail and that costs money.
10... try 2 lol.  We could hear it failing on the first print.

You havent lived until you hear the emulsion crackling with the squeegee stroke.

And we have officially dragged the thread off topic, but it’s nice to see some good come of all of this.

Good customer service, points on some anomalous problems and I get to “spread some technical love” as it were. Win-Win.
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Offline jvanick

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Re: LED Bulbs Already Failing
« Reply #122 on: February 24, 2016, 03:03:13 PM »
I have one of those...

When exposing for best resolution,  I was FAR under cured.

And then delamination!

Resolution excellence is nothing if it all falls off at 10 impressions!

Mesh count and thread thickness also play a part in useable resolution, you have to have threads to hold the dots in place and the emulsion stencil has to survive the required number of impressions or... well fail and that costs money.
10... try 2 lol.  We could hear it failing on the first print.

You havent lived until you hear the emulsion crackling with the squeegee stroke.

And we have officially dragged the thread off topic, but it’s nice to see some good come of all of this.

Good customer service, points on some anomalous problems and I get to “spread some technical love” as it were. Win-Win.

not so sure about off topic. -- as the delamination, detail and emulsion 'cure' DEFINITELY play into LED exposure unit testing.

Offline Rockers

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Re: LED Bulbs Already Failing
« Reply #123 on: February 24, 2016, 06:49:08 PM »
Exposure times would have been above the recommended ones by the emulsion manufacturer but I can promise you there would be no useable fine details left on a screen. All I`m saying is I can hold a lot more fine lines on a 150-s by exposing it on a MSP3140 then on the LED unit. And believe me we have not changed the way we make film positives over the last few years.

Is not the point right there? You are apples and orange-ing this...

I have a brand new truck and it is the same brand (UV exposure) but one has dual back wheels and and a big block and the newer less expensive one is small block standard - but I don’t get why they won’t do the same job...

Tubes 15-17% loss (but I can still get more and better halftone imaging than 60% of the industry with base level equipment)

LED - 7-8% loss

MH - 3-5% loss

Then the size, features, active life, maintenance, price, energy use....

All different - not bad just different.

I cannot expect my Jeep to be able to keep up with a Mustang now can I? Does that make my trashy Jeep bad?


If that is the case why not being told so right away before the purchase and have the equipment shipped half around the world. Why not say right away you have to expect loss in image quality or you can`t hold as fine detail as on your MH unit, and I`m not talking only halftones here but as well lines which I would expect to hold on a 225-s yellow mesh. Unless of course everyone in my shop`s gone totally stupid coinsidently around the same time as we installed this unit.
« Last Edit: February 24, 2016, 07:11:06 PM by Rockers »

Offline DouglasGrigar

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Re: LED Bulbs Already Failing
« Reply #124 on: February 25, 2016, 03:24:20 AM »
Exposure times would have been above the recommended ones by the emulsion manufacturer but I can promise you there would be no useable fine details left on a screen. All I`m saying is I can hold a lot more fine lines on a 150-s by exposing it on a MSP3140 then on the LED unit. And believe me we have not changed the way we make film positives over the last few years.

Is not the point right there? You are apples and orange-ing this...

I have a brand new truck and it is the same brand (UV exposure) but one has dual back wheels and and a big block and the newer less expensive one is small block standard - but I don’t get why they won’t do the same job...

Tubes 15-17% loss (but I can still get more and better halftone imaging than 60% of the industry with base level equipment)

LED - 7-8% loss

MH - 3-5% loss

Then the size, features, active life, maintenance, price, energy use....

All different - not bad just different.

I cannot expect my Jeep to be able to keep up with a Mustang now can I? Does that make my trashy Jeep bad?


If that is the case why not being told so right away before the purchase and have the equipment shipped half around the world. Why not say right away you have to expect loss in image quality or you can`t hold as fine detail as on your MH unit, and I`m not talking only halftones here but as well lines which I would expect to hold on a 225-s yellow mesh. Unless of course everyone in my shop`s gone totally stupid coinsidently around the same time as we installed this unit.

Where has anyone said that any LED unit would hold the same or work the same as a MH? No LED multi-bulb unit will work the same as a MH.

There are some testing, coating, emulsion and mesh choices all going on at the same time, I wonder about the requested or desired results and capacity of all of the above.

I observe "in the wild" almost every shop out there will under-link (far lower than capacity of the emulsion) screens and live with a much lower life and durability thinking that is how detail will get to the print (and it some cases it can - at a cost).

Most students and shops I help are shocked at how much detail can be had even with the low-cost FL tube units when the component parts are matched, clearly not a MH, but lots of other choices are going on.

I am most concerned that I’m seeing the “solid step” listed on this thread and it of course is only showing resistance to a particular level of delamination.

Ninety nine out of a hundred garment screen printing shops will find all of the features of an LED unit a great match - speed of a MH unit, size of a FL tube unit, and lower price and much lower energy use.

At the start of the thread the issue was one of technical service, once everyone got on the phone and started talking solutions started to flow, that is what I expected. My second issue was then illuminated when we clearly started to see the mis-application of a “test” and the subsequent problems.
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Offline tonypep

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Re: LED Bulbs Already Failing
« Reply #125 on: February 25, 2016, 07:33:15 AM »
This is all educational (to a small few I suspect} but I prefer to come in and get product out the door. Sorry but this thread has little to do with the 99% of shops that have figured it out long ago. I'm all for process improvement  but theres laboratory, and boots on the ground. I prefer the latter. To be sure, I am open to beta test products and equipment but with a high degree of reservation. Sorry but its not rocket science.

Offline alan802

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Re: LED Bulbs Already Failing
« Reply #126 on: February 25, 2016, 09:51:33 AM »
Whether or not anyone ever said to expect results below a good metal halide unit, the LED unit that I'm looking at didn't live up to expectations.   I can promise you all the hours I spend reading and researching, I NEVER SAW ANYTHING REMOTELY CLOSE TO "don't expect the LED to be as good as your metal halide".  When we bought our LED there was almost nothing out there about our specific unit.  Now some will say I was banking on the different brands being pretty close in performance because there was enough info about the Starlight and honestly, I WAS.  That's my fault, and I can promise you it won't happen again and I'll make sure that others don't make the same mistake. 

I'm going to go back and re-read the last few pages just to make sure I'm not misinterpreting anything and make an ass out of myself.

I'll say this again, we've managed to get detail that in the beginning we couldn't get, but if you have to throw all the cargo off the ship to get it to float it's not really a cargo ship is it?  Meaning, the screens aren't usable for anything over 100 pieces due to the need to underexpose to achieve the detail.  I wish we had imagesetter quality film and not just the Epson stuff because there is a pretty noticeable difference between the results from the Chromaline expo calculator and our own calculator we made.  At least the expo calculator allows us to burn longer without as much undercutting and risk for overexposure behind the image.  Of course the D-min and D-max of our film doesn't match the quality of an imagesetter and I suppose one could blame that on us for not using the best film possible.

I've been looking at my latest expo calculator results and I'm fine with what we got, but unfortunately I know if we put this screen on press the real proof is in THOSE results.  I've had conversations with guys who have forgotten more than I'll ever know about stencil development who have basically all told me the same thing that match perfectly with what I've seen with real world results.
 
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Offline ScreenFoo

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Re: LED Bulbs Already Failing
« Reply #127 on: February 25, 2016, 11:32:35 AM »
I think plenty of people pointed out that it sounded too good to be true and probably was.  Over at t-shirtforums the "baby joe" guy was telling everyone their MH units were worthless, and his unit was better in every way.  I was not the only person who disagreed with him.
As mentioned in this thread, he went on to make light bars for Vastex.

Funny thing is, LDtronix's account got nuked, so you will never get to read the bat-crap crazy stuff he was claiming.

And the internet marches on...

Offline DouglasGrigar

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Re: LED Bulbs Already Failing
« Reply #128 on: February 25, 2016, 12:16:17 PM »
This is all educational (to a small few I suspect} but I prefer to come in and get product out the door. Sorry but this thread has little to do with the 99% of shops that have figured it out long ago. I'm all for process improvement  but theres laboratory, and boots on the ground. I prefer the latter. To be sure, I am open to beta test products and equipment but with a high degree of reservation. Sorry but its not rocket science.

That’s not exactly fair, it is similar to “nuff said” to try and end any conversation.

I know you remember all the grief Don Newman got for his ideas and frames, how he had to fight for just about every inch, at a time when "boots on the ground” was wooden frames. A time when rope and groove screens were still common and we both remember how that was back then.

I have been telling people that just like the massive contribution Don had for our industry, the LED technology (regardless of who) is going to have an impact as similar as that was.
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Offline alan802

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Re: LED Bulbs Already Failing
« Reply #129 on: February 25, 2016, 01:11:28 PM »
This is all educational (to a small few I suspect} but I prefer to come in and get product out the door. Sorry but this thread has little to do with the 99% of shops that have figured it out long ago. I'm all for process improvement  but theres laboratory, and boots on the ground. I prefer the latter. To be sure, I am open to beta test products and equipment but with a high degree of reservation. Sorry but its not rocket science.

That’s not exactly fair, it is similar to “nuff said” to try and end any conversation.

I know you remember all the grief Don Newman got for his ideas and frames, how he had to fight for just about every inch, at a time when "boots on the ground” was wooden frames. A time when rope and groove screens were still common and we both remember how that was back then.

I have been telling people that just like the massive contribution Don had for our industry, the LED technology (regardless of who) is going to have an impact as similar as that was.

I'm all about hyperbole but I'm going to have to step in here and disagree A LOT.  First off, LED could very well be great...one day, and some units may be close to greatness but some are not.  I'll list a few that are way above LED when it comes to being a huge game-changer.  Automatic presses (and all the advancements that have come along within them), roller frames, metal halide, CTS, and how about the dinky little $200 Epson inkjet printer?, thin thread mesh, advancements in ink technology, and I'm sure there are a few more.  I don't want to get in a debate about how good roller frames are or how many on this forum are able to do award winning work with statics, that's not the point.  When it comes to industry game-changers LED isn't in the top 5.  I don't see how it could even come close to having the same impact that roller frames can have for those who chose to use them to their potential.
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Offline blue moon

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Re: LED Bulbs Already Failing
« Reply #130 on: February 25, 2016, 01:36:07 PM »
I am again going to chime in here. . .

Rockers, the LED unit is different from the standpoint that when compared to MH it will have a very small amount of undercutting. Adjusting your RIP to compensate for this should sort out your thin line issues.

Alan, when I reported, I clearly said that it "was very close to MH and for 99% of the shops it will not make a difference." Only thing we could see in testing was the we were holding a 3% dot with MH and 5% dot with LED. As mentioned above, adjustment in the RIP should address that.

ScreenFoo, Lou's LED units are the only ones I am aware of that have all the features properly designed unit should have. Most manufacturers did not disclose all the details he did so it is possible they have them too, but as of right now I know of faults in many other units on the market that he (and Vastex) are addressing in their design. While I don't know anything about the manufacturer of the LEDs and their standards, information Lou shared on the wavelength, power supply, cooling, proper light field distribution and so on is on par or better than anything else I've seen. While many other units might have equivalent or even one feature that is better than the LDTronix/Vastex setup, every one of them I've measured and tested had at least one significant (at least to me) downfall.

I realize there is an issue with Alan's and Rockers units and obviously I don't know why and what it is, but the one we tested for two months was rock solid and I would not hesitate to use it for our main light.

As Douglas says, measuring and adjustments have to be made when new piece of equipment is introduced into the workflow. We adjusted the exposure times on few occasions, in some cases depending on the mesh color (were surprised to see the 305Y needing as much light as 110W for example), screen placement and with current unit the distance to glass. . .

pierre
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Offline Frog

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Re: LED Bulbs Already Failing
« Reply #131 on: February 25, 2016, 01:37:20 PM »
My take on LED's in general. (and I mean the bulbs in general, not exposure units)
They are definitely the light source of tomorrow. Almost there for home use as soon as they are available in the $1 range like CFL's became whether with rebates, or subsidies, or mere competition. They will be come a near necessity for conservation and economics.

Except perhaps for shops are burning all day long, I don't think that the conservation thing is the driving force here in our industry.
As more and more emulsion makers start tailoring their products to working with the different light sources, they will definitely grow in popularity to eventually become the norm.
Like was mentioned, the possible exposure power of an MH along with the flat compact design of a fluorescent unit is a dream.

That said, there will be growing pains.
That rug really tied the room together, did it not?

Offline ScreenFoo

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Re: LED Bulbs Already Failing
« Reply #132 on: February 25, 2016, 02:01:32 PM »
Rockers, the LED unit is different from the standpoint that when compared to MH it will have a very small amount of undercutting. Adjusting your RIP to compensate for this should sort out your thin line issues.

Alan, when I reported, I clearly said that it "was very close to MH and for 99% of the shops it will not make a difference." Only thing we could see in testing was the we were holding a 3% dot with MH and 5% dot with LED. As mentioned above, adjustment in the RIP should address that.

ScreenFoo, Lou's LED units are the only ones I am aware of that have all the features properly designed unit should have. Most manufacturers did not disclose all the details he did so it is possible they have them too, but as of right now I know of faults in many other units on the market that he (and Vastex) are addressing in their design. While I don't know anything about the manufacturer of the LEDs and their standards, information Lou shared on the wavelength, power supply, cooling, proper light field distribution and so on is on par or better than anything else I've seen. While many other units might have equivalent or even one feature that is better than the LDTronix/Vastex setup, every one of them I've measured and tested had at least one significant (at least to me) downfall.

First off, I didn't mean to imply the guy hadn't done his homework on the EE/ME side of the issue.  It was just another pitch that sounded to me just like the "Sell your presses, DTG is here" BS that we've all read a million times now.

Second, when you say "Light field distribution" do you mean you measured how close the light is to collimated, or that you measured to make sure one area of LED's wasn't brighter than some other area of LED's? 

IMHO the former is at least as important as the latter for a quality stencil.

Anyway, keep up the R&D guys.  ;)

Offline blue moon

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Re: LED Bulbs Already Failing
« Reply #133 on: February 25, 2016, 02:11:57 PM »
Rockers, the LED unit is different from the standpoint that when compared to MH it will have a very small amount of undercutting. Adjusting your RIP to compensate for this should sort out your thin line issues.

Alan, when I reported, I clearly said that it "was very close to MH and for 99% of the shops it will not make a difference." Only thing we could see in testing was the we were holding a 3% dot with MH and 5% dot with LED. As mentioned above, adjustment in the RIP should address that.

ScreenFoo, Lou's LED units are the only ones I am aware of that have all the features properly designed unit should have. Most manufacturers did not disclose all the details he did so it is possible they have them too, but as of right now I know of faults in many other units on the market that he (and Vastex) are addressing in their design. While I don't know anything about the manufacturer of the LEDs and their standards, information Lou shared on the wavelength, power supply, cooling, proper light field distribution and so on is on par or better than anything else I've seen. While many other units might have equivalent or even one feature that is better than the LDTronix/Vastex setup, every one of them I've measured and tested had at least one significant (at least to me) downfall.

First off, I didn't mean to imply the guy hadn't done his homework on the EE/ME side of the issue.  It was just another pitch that sounded to me just like the "Sell your presses, DTG is here" BS that we've all read a million times now.

Second, when you say "Light field distribution" do you mean you measured how close the light is to collimated, or that you measured to make sure one area of LED's wasn't brighter than some other area of LED's? 

IMHO the former is at least as important as the latter for a quality stencil.

Anyway, keep up the R&D guys.  ;)

I have no means to measure the light collimation, but the field distribution so far has been better than anything else we tested (and few manufacturers declined to have us measure it).

Biggest problem with Lou was that he was so jaded that nobody would listen to what he was saying so he started arguing with ppl. Once he brought the unit to our place and we tested it, it turned out that his claims appeared to be true. We were getting significantly shorter exposure times and the stencil held up to the printing and washout just as he claimed. He was on the site here and discussed things pleasantly for months. It started off shake before the testing, but everything calmed down afterwards.
Lou and I talked about several changes to his unit that were addressed in the Vastex model we tested. Then after we used the Vastex version for a couple of months, several updates to the unit were suggested (the vacuum pump being one of them) by Richard Greaves and myself. To their credit, anything related to performance of the unit was changed pretty quickly. We brought the meters and took some measurements few months after returning our unit and confirmed it all in person. From what I can remember there were two suggestions that were not changed, one hand operation of the lid and digital timer (rather than the analog version they use).

pierre

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Offline DouglasGrigar

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Re: LED Bulbs Already Failing
« Reply #134 on: February 25, 2016, 06:56:55 PM »
I'm all about hyperbole but I'm going to have to step in here and disagree A LOT.


It happens - and yes we are going to disagree.


Quote
First off, LED could very well be great...one day, and some units may be close to greatness but some are not.

I’m not saying great, identifying it as a “game changer” a “black swan” in it’s ability to force us to look at things with exposure we have never seen before (like the queer bits about linking acceleration).

I’m not even saying the roller frames are “all that” (have a major place yes) I’m saying that we learned a LOT about mesh and tension directly from a singe NEW innovation/technology - LED is just like that. Automatic presses a continuation (impact yes but not the same) there is no former pathway for the LED technology as with much of your list - All big impact yes, but I stand by my prediction that by the very nature of LED it will be a game changer for many reasons including what we are going to learn about emulsions and exposure.

We had mesh already, we learned about tension with the aid of Don and his product, and that I what I am pointing out - it is the same with the LED, and I am convinced this will play out in a similar way.
« Last Edit: February 25, 2016, 07:49:36 PM by DouglasGrigar »
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