ROUND II: Daguin inventory reduction sale!

[Gun]

You still selling that 1-3mW HeNe? $40-$50 seems pretty cheap, will I have to buy other stuff to run it? Are HeNe's hard to mantain? What wavelenth?

Thanks,
Gun

 

[Sigurthr]

Standard HeNes need pretty much no maintenance. As they age they may get hard to start as the helium pressure changes, but Dave would inform you of such in the listing. For hobbyist purposes if it lights and lases first try, it will probably outlast you. (Keep in mind they used these in price scanners that were on 24/7 for decades).

I use one as a night light, it has been running indefinitely for years.

 

[Speedy78]

Id like to see pictures of this night light.

 

[Gun]

Standard HeNes need pretty much no maintenance. As they age they may get hard to start as the helium pressure changes, but Dave would inform you of such in the listing. For hobbyist purposes if it lights and lases first try, it will probably outlast you. (Keep in mind they used these in price scanners that were on 24/7 for decades).

I use one as a night light, it has been running indefinitely for years.

Sounds pretty good, I'm fairly interested although now I have to choose between getting a new laser, HeNe or flashlight!

 

[Sigurthr]

Id like to see pictures of this night light.

 

[Gun]

That's really cool! So HeNes don't emit a dot or a beam as such, just sort of a glow?

Dave, I'm interested in the 1-3mW HeNe, if you could respond to my PM regarding shipping, that would be great.

What do you guys think? Lab Laser vs HeNe vs Flashlight

 

[Sigurthr]

Yeah they emit a beam/dot too. If you have a bare tube like I do you can see the plasma inside the cavity, which emits broad spectrum light (several bands between UV and IR).

I bought up a ton of Melles Griot heads in auction a few years ago and repaired them for resale. I kept a few of the nicer tubes and heads, this is one of them.

 

[daguin]

Absolutely awesome Dave! I eagerly await receiving this beauty.

Since you've got it up and running full blast, do you know if the linked remote scheme (with 1k limiting resistor in series with 1.5k pot) limits the tube current to the safe/healthy maximum tube current, or are you using a remote with a different current limitation. I just don't want to risk damaging such an awesome laser.

The remote built from that schematic will allow up to 12A.
The PSU will only produce about 10.5A
"Standard" current for 24/7 running is about 7A
I endeavor to run mine about 1A below the maximum
When I do "maintenance burns", I run them at 7A

Running the head at 10.5A for long periods will reduce the life of the tube
At the max current, there is the possibility of the filament to be ablated to failure
We report the output, at maximum current, to show the relative health of the tube

You still selling that 1-3mW HeNe? $40-$50 seems pretty cheap, will I have to buy other stuff to run it? Are HeNe's hard to mantain? What wavelenth?

Thanks,
Gun

I have that one available
It is pretty inexpensive for a tube with a lab-style PSU
It is 632nm (red)
This unit is Plug-n-Play
Unfortunately, this one only runs on 110V mains
Also, it is contained in a housing so you cannot see the plasma
Based on your inquiries herein, it would appear that you are more interested in a bare tube HeNe

The bare tube green HeNe that I have available will run on 110V or 230V mains
It has a brick-style PSU
Shipping on it would also be lower because it is smaller and lighter than one with a Lab-style PSU and in a housing
This one would require you to attach a cord to the input wires so you could plug it in
You would also have to build some sort of display mount if you wanted to use it like a night light
I have a Green HeNe, with the housing cut away, on my desk, that I use as an accent lamp

Also, bear in mind that a bare tube is a bit more "dangerous" than one in a housing
The tube acts as a capacitor
It WILL bite you, if you are careless
It will not injure you, but it will hurt

HeNe's can be run 24/7 for tens of thousands of hours
Also, they make no noise while running (unlike argons )

Peace,
dave

 

[Gun]

The remote built from that schematic will allow up to 12A.
The PSU will only produce about 10.5A
"Standard" current for 24/7 running is about 7A
I endeavor to run mine about 1A below the maximum
When I do "maintenance burns", I run them at 7A

Running the head at 10.5A for long periods will reduce the life of the tube
At the max current, there is the possibility of the filament to be ablated to failure
We report the output, at maximum current, to show the relative health of the tube




I have that one available
It is pretty inexpensive for a tube with a lab-style PSU
It is 632nm (red)
This unit is Plug-n-Play
Unfortunately, this one only runs on 110V mains
Also, it is contained in a housing so you cannot see the plasma
Based on your inquiries herein, it would appear that you are more interested in a bare tube HeNe

The bare tube green HeNe that I have available will run on 110V or 230V mains
It has a brick-style PSU
Shipping on it would also be lower because it is smaller and lighter than one with a Lab-style PSU and in a housing
This one would require you to attach a cord to the input wires so you could plug it in
You would also have to build some sort of display mount if you wanted to use it like a night light
I have a Green HeNe, with the housing cut away, on my desk, that I use as an accent lamp

Also, bear in mind that a bare tube is a bit more "dangerous" than one in a housing
The tube acts as a capacitor
It WILL bite you, if you are careless
It will not injure you, but it will hurt

HeNe's can be run 24/7 for tens of thousands of hours
Also, they make no noise while running (unlike argons )

Peace,
dave

Thanks Dave, I've replied to your PM

 

[daguin]

Thanks Dave, I've replied to your PM

There is some info in my reply to your PM that may be of interest to others

Remember, with this one, where you live, you will have to have a 230V-110V converter to use it.
This PSU is not switchable for voltage

It looks like shipping will be about $50 to Australia
I will only charge the actual shipping cost

One of the reasons that bare tubes are more expensive than housed tubes is that it is so difficult to remove them from their housing

There is barely 3-4mm clearance between the tube and the housing and they are held in place by adhesive silicone.
The silicone is "squished" in via holes in the housing, spaced around the housing, a few cm from each end
There are a couple of ways to remove the housing.
You have to cut it off with something like a Dremel with a cutting/grinding blade
or
You have to cut the silicone by sliding something like a piano wire or sheet metal, that is thin enough to fit between the housing and the tube

Both methods risk breaking the tube

Peace,
dave

 

[Speedy78]

If only I had the money for the green.

 

[Sigurthr]

I found that you can also bake the melles griot cylindrical heads to the point that the silicone softens and then push out the tube safely. I found this to be the best method so far. I did several with piano wire and it was a nightmare. Dremeling the case worked too but way risky; I had a shattered wheel scratch the HR lens exterior once.

 

[daguin]

I found that you can also bake the melles griot cylindrical heads to the point that the silicone softens and then push out the tube safely. I found this to be the best method so far. I did several with piano wire and it was a nightmare. Dremeling the case worked too but way risky; I had a shattered wheel scratch the HR lens exterior once.

I wonder if a heat gun would be enough?

Does the silicone "smear" over the outside of the tube this way?

Peace,
dave

 

[Sigurthr]

I first used a propane torch waved around for equal heating, I think a painters heat gun would work too. Only one of the heads had some minor smearing in one spot, I think it just got too hot there as it came off easily elsewhere. I scraped off the smear with a knife and then got the bits off using a nonstick safe Brillo pad dunked in 91% isopropyl.

Some heads had only a quarter sized blob injected in per hole, but some were damn near potted with the stuff! I wish they had used a more service friendly method of securing it. Likewise they use soft rubber potting for some ballast resistors, and others used a rock hard plastic.

 

[daguin]

I first used a propane torch waved around for equal heating, I think a painters heat gun would work too. Only one of the heads had some minor smearing in one spot, I think it just got too hot there as it came off easily elsewhere. I scraped off the smear with a knife and then got the bits off using a nonstick safe Brillo pad dunked in 91% isopropyl.

Some heads had only a quarter sized blob injected in per hole, but some were damn near potted with the stuff! I wish they had used a more service friendly method of securing it. Likewise they use soft rubber potting for some ballast resistors, and others used a rock hard plastic.

Yea. Many of the "dead" HeNe's out there simply have a burned resistor buried in that rubber/plastic

I'll have to try the heat gun on a couple of "dead" Greens I have sitting here

Peace,
dave

 

[Speedy78]

Would the PSU from my red HeNe work for the green too? If so will just have to hunt around for just the tube.