HPDFO Universal Laser Worth it?

[George Beck]

Hi All

This is for the Universal Laser folks out there. I am considering the HPDFO accesory for my Platform Versa Laser 60 W. I currently use a 1.5 lens and I am looking for a fine point for intricate carvings and small fonts. Most of my work is on wood. Is this worth the price? Those of you who have this option, what do you think of it?

Thank you for your attention.

George

[Mike Null]

George

I don't own, nor have I used the HPDFO optics, but I do a fair amount of wood and I don't see that you can benefit that much more than what you have with your current lens. If you were working with substrates that can produce really high resolution engraving then my answer might be different.

I use a two inch lens and have been very satisfied with the detail I've been able to achieve.

[Dan Hintz]

For wood? I don't see the benefit... a standard 2"FL lens will net you 5mil focal point, beyond what typical wood can resolve.

If you were doing anodized aluminum or similar, I would highly recommend it for detailed work.

[Scott Shepherd]

Depends on what you want to do with it. I have a sample of the aztec calendar on my desk done with it and it's in alder, and it's amazing. Having said that, I do a job with a 3 point font frequently. I do that with a 2.0 lens. I think it's an amazing option and the work I have seen done with it is simply beautiful. But it's all been stuff like detailed photos, etc., all of which I have never had any luck selling.

Here's a sample of the aztec calendar. Scroll down to my post with the photo.

http://www.sawmillcreek.org/showthread.php?148121-Aztec-calandar.

[Richard Rumancik]

. . . I currently use a 1.5 lens and I am looking for a fine point for intricate carvings and small fonts. Most of my work is on wood. . . .

George, I'm not a ULS owner so can't comment directly on the accessory. I suppose you are the best judge as to whether the HPDFO is necessary for what you want to do.

Before buying it, make sure you have optimized the 1.5" setup. By that, I mean make sure you have a level workpiece (or can adjust it level) and ensure that your focus is optimum. Normal tables are not level enough for fine work and you may need a secondary adjustable table surface. The probes and auto-focus features are not ideal for fine work. Every lens is a bit different and you may find that you need to make a better focusing tool designed for this lens. I think testing on anodized aluminum will help you find the exact focal point as optimum focus is more apparent (wood is not good for calibrating the FL.)

Keeping work level and in-focus over the whole table can be difficult. If your part (work area) is small - say 12" square - it is easier to keep the work area level and in-focus. If this is the case, you could consider trying a shorter focal length lens - 1" or 1.25" FL. There are challenges to this because of decreased depth of field, but it will give you a smaller spot size. You should be able to get less than .005 spot with a 2", about .003 with your 1.5" lens, and perhaps .002" with the 1" FL lens. Might not sound like a huge improvement, but if you are trying to use high resolution (500-1000 dpi) then getting a spot smaller than .003 is warranted. Lasering .003"+ dots .001" apart (1000 dpi) really doesn't make much sense.

A shorter FL lens would cost considerably less than the HPDFO; of course it won't give you as good a resolution. I think ULS claims a spot size of .00125" or so which is pretty much at the limit of a CO2 laser. You won't achieve this spot size without their beam expander spstem.

Maybe you could send a sample file to ULS and see if they will run it with 1.5" lens and with HPDFO optics.

[Chuck Patterson]

I asked for a quote on this yesterday and this is the reply I got back today:

The HPDFO is $2,650.00 plus some freight.

[Viktor Voroncov]

Have heard on one trade show from ULS dealer that HPDFO allowed direct engraving on metals, even on steel? Is it true?

[Dan Hintz]

True, but it's still pretty darn slow. For a true black with a 30W cartridge, speed is around 1%. As speed goes up, the color shifts towards a lighter and lighter gray.

[Viktor Voroncov]

Dan , and what you can say about MUCH HIGHER POSSIBILITY OF REFLECTION with use of HPDFO which can even damage laser tube (also from show, but heard from ULS competitor :) )

[Dan Hintz]

There's no greater chance of reflection with the HPDFO than with any other lens selection.

Tube damage from reflections is a very real concern in high-powered systems (think kW) because the reflected beam has the power to melt metal. Reflecting this kind of power back onto the optics and wave walls is a guaranteed replacement. With our low-powered systems, the worst you could do is hit an optical mount in such as way as to heat it up, or possibly damage any one-way coatings that might exist on combiner optics... this might require a rebuild of optics in the worst case scenario, but it's highly unlikely.

[Mike Lassiter]

I have the HPDFO lens. I can't say that I have tried it against the 2" focus lens on wood, but I do believe there is a visible difference in detail on acrylic going to the HPDFO as compared to the 2" lens. I have ULS ILS laser and the choices of lens for me are HPDFO, 2" and 4". I have done photos on acrylic using the 2" lens and the detail is not as sharp as with the HPDFO lens. As someone else mentioned - when you try to place 500 - 1000 DPI and the beam focal point 0.004" or so you are burning the same spot multiple times and washing out details and sharpness that doesn't happen when the beam focal point is 0.00125". I could see this also for some woods if you are doing photos, but you can also lose details in the grain of the wood, and the 2" lens maybe a good choice generally speaking.
Another thing with the HPDFO lens is you can engrave stainless steel. I did a chef's knife for my daughter for her birthday that turned out so-so. The one thing with it was that I made sure to level the blade lengthwise as it was thicker at the handle end than the tip end, but I didn't think to also level it to compensate for the taper of the blade from the cutting edge to the opposite side. The HPDFO lens did a good job, but because the focus varied due to the taper the color also varied from a good black color to a blueish color when focus was lost.

[Bruce Boone]

I do mainly Cermark on titanium and haven't noticed a big difference using the HPDFO as opposed to my 2" lens. Maybe just a slight bit better, but it doesn't seem to be as sharp as the numbers would indicate. Part of my issue is that I do curved rings, so I'm pushing the focal window. I imagine that the Cermark itself also loses some resolution just due to the fact that it starts as powder.

[Mike Null]

I've always been able to mark stainless steel with my 2" lens 45 watt Trotec. It is too slow for commercial work though. Also, if the ss is very thin (.015" or less) the high heat can distort the metal.

[George Beck]

A lively discussion as usual. My thanks to everyone. I am getting good results with a 2.0 lens and I have a 1.5 which I use for fine fonts (like the declaration) and fine 3d graphics. I guess I am struggling with the cost. I am sure I could do very fine carvings with the HPDFO but at $2,800 it would have to do a lot of work and it has not been my experience so far that people know or are willing to pay for the finer detail. I am constantly explaining that I run most work at 500-900 dpi in lieu of 100-200 dpi and thus can't do a $15 plaque. I have one inquiry for the Declaration of Independence 50 copies done on 12 x 15 cherry but they want to pay $50 each (I am assuming so they can sell them for $150). I would love to have the flexibility of this lens but I think it will come down to a cost vs return decision. I guess I was hoping to hear from the forum that it is the best thing since toast, but that doesn't seem to be the case. Thanks again!

George