(reci) Tube

[Tone Lesar]

Hello!

I am beginer.

What is typical for (reci)laser tube?



What is the difference between simple and (reci) laser tube?

[Dan Hintz]

What is typical for (reci)laser tube?



What is the difference between simple and (reci) laser tube?

Typical what? Price? Size? Weight?

[Tone Lesar]

:) My English is so good, that sometimes I surprise myself I see, that I surprised you too Dan. I meant to ask what advantages it has for engraving. I saw in the offer that engraving machine with RCEI tube costs more.

[Dan Hintz]

The advantage is supposed to be that the tube will last longer and give more power per unit length than the typical non-Reci tubes... whether or not that claim holds true is somewhat debatable. Those that have them seem happy with the purchase, but few here have used both long enough to make a valid comparison (Rodney Gold is one such person).

They may very well have better quality control than other companies making the tubes, which would lend credence to their claim of longer life.

The claim of stronger power per unit length may be valid, as well, but it's difficult to say without having one in hand to measure important characteristics. From what little Rodney has posted in the past about his tests, it appear Reci may be overdriving their tubes to the point of moving past the typical lasing mode of TEM00 (typical low-power metal and glass tubes) into TEM01. This has the advantage of getting more power of of a specific length of tube, but the disadvantage is the output beam is no longer Gaussian in distribution. This would prove more useful in vectoring rather than engraving.

If I was purchasing a machine for high-power vectoring only, I would consider the Reci tube. If it was for combined vectoring / engraving, I would want to know the answer to the above paragraph before purchasing.

[Rich Harman]

At a year and a half my 80 Watt Reci has shown no signs of diminished power.

I often lower the table several inches and fire the laser onto a piece of thermal paper to verify alignment. The resulting mark on the thermal paper looks like TEM00 to me.

[Rodne Gold]

Same here , my Reci tubes still going strong for 2 years , been thru 2 cheapys , one died , the other we broke.
Overdriving the reci will shorten life a lot , like at max current..we limit current to 90%
As to actual wattage , I dont have a tester so can't say exactly. Beam quality is good

[Ernie Balch]

My RECI 80W tube is 1.5 yrs old and still going strong (knock on wood). I have not analyzed the beam but am getting a single spot when engraving wood as seen in a magnifier.

I do get some extra trailing spots at higher powers as if the tube or electronics wants to throw in occasional extra pulses. This is not observed in the 10 to 20% power range but is seen at 25 and 30% setting while engraving. This is not a problem if you are not inspecting with a magnifier. The problem is seen in both single and bi-directional engraving and is about equal to the left and right going raster mismatch seen under magnification. In other words about one laser spot width in size.

[Gary Hair]

TEM00 TEM01

Just in case anyone, like me, wondered what in the world Dan was talking about, here is a picture:

http://i249.photobucket.com/albums/gg201/imdguin/LaserModes.png

[Walt Langhans]

Just in case anyone, like me, wondered what in the world Dan was talking about, here is a picture:

http://i249.photobucket.com/albums/gg201/imdguin/LaserModes.png

Yeah I still don't quite understand what I'm looking at... is that how the dot looks under a magnifying glass? And if so why? As in why aren't they all just a single dot?

[Dan Hintz]

I often lower the table several inches and fire the laser onto a piece of thermal paper to verify alignment. The resulting mark on the thermal paper looks like TEM00 to me.

Rich,

Useful info... would you mind repeating the test with a block of acrylic when you get a chance? The thermal paper isn't nearly accurate enough, but it's a start. I'd really like to nail down once and for all if those tubes are still TEM00...

[Tone Lesar]

Thank you for useful information about RECI tube.

[Rich Harman]

Rich,

Useful info... would you mind repeating the test with a block of acrylic when you get a chance? The thermal paper isn't nearly accurate enough, but it's a start. I'd really like to nail down once and for all if those tubes are still TEM00...

Sure, I can do that. But why do you say thermal paper is not accurate? I don't burn through it. I fire the laser for a fraction of a second and the paper darkens wherever there is heat.

[Gary Hair]

Yeah I still don't quite understand what I'm looking at... is that how the dot looks under a magnifying glass? And if so why? As in why aren't they all just a single dot?

Those are all good questions, I'm sure most of us have the same questions. I'm assuming that they depict the shape of the dot but I have no idea why they look different. I could research it and find the answers, but, to be honest, I don't need that tidbit of knowledge crowding my brain, it's full enough already...

[Michael Hunter]

I caught a bit on "How Its Made" where a guy was doing final adjustments on a HUGE laser (the beam must have been over an inch in diameter).
He had a big pile of very thick acrylic blocks which he put in front of the laser (one at a time) and fired it for a second or two.
The first blocks were just a jagged mess, but when he had finished adjusting the mirror the final block had a nice round gausian-contoured deep depression in the middle of it.

My Epilog does not allow me to fire the laser without movement of the carriage, but it would be interesting to put a piece of acrylic near the laser output (before the first mirror) and see what the beam looks like.

[Rich Harman]

I think this is the video that Michael referred to, thickest acrylic I have is 1/2" but I'll give it a try...


http://www.youtube.com/watch?v=M_ayRAHezjM

[Michael Hunter]

That is not the video that I remember - but very similar.
The one I saw made more of a thing about getting the beam perfect.
I also cringed a lot as I thought the guy was going to cook his arm!

[Rich Harman]

I created another thread (http://www.sawmillcreek.org/showthread.php?200069-Testing-the-Reci-tube-for-TEM00) to show the results of testing the Reci tube for TEM00.

[Vicki Rivrud]

- again I had no clue what you are talking about but our Enquiring minds want to know

http://www.cvimellesgriot.com/products/Documents/TechnicalGuide/Transverse_Modes_and_Mode_Control.pdf (http://www.cvimellesgriot.com/products/Documents/TechnicalGuide/Transverse_Modes_and_Mode_Control.pdf)

Ahey - I'll definetly work better in the morning :) - perhaps the laser will too . . .

As for the RECI tube - we switched from the standard Chinese tube because the quality & longevity just wasn't there. Had too many go bad sitting on the shelf, short life or weak performance. At least with the RECI the warranty is much better and so far our 1st RECI is out performing the standard tube. There are a few imitations out there so ask about the warranty!

We've been extremely pleased with the RECI - mine is a W-6 and I cut paper to delrin, wood to acrylic, leather to fabric, to engraving on all sorts of glass/stone etc and it hasn't let me down yet - knock on wood.

Happy lasering,
Vicki

[Michael Hunter]

Here are the results of by beam-test firing -

Epilog 60W RF tube. Now 9 years old and power probably down to under 30W.

I'm quite pleased with the result for such an old tube.

The point of the cone is about 5mm into an 8mm thick block of acrylic.
It all happened so quickly that I'm not sure how long it took - perhaps a second.
It started off looking more gaussian, but by the time that I opened the lid (when the flames started!) it had gone pointy. Probably the "waveguide effect" that Dan talks of.

[Dan Hintz]

I can't believe this thread has not prompted anyone to remove their focus lens and try making a 3D image of some sort...