[MonoNeuron]

Here is the link to Mr Xu's site for a price list of the tubes and the power supplies.
http://www.modelcn.cn/laser%20tubes%20power.html
I am buying a power supply from him for my 35watt laser. So far he has been very quick with his mails and a little hard to understand sometimes but his english is much better than my chinese. I paid by direct International money transfer and my bank slugged me $22AUD for the transaction and the Bank of China slugged Mr Xu $37USD for transfering to his account. A bit rude of the Bank I thought. I hope he can find a better way of money transfers.
The Neuron.

[MonoNeuron]

I also forgot. He has a sale on now but it will probably end soon at the start of the New Year. Also, once you buy from him then you become eligable
for discounts which are very good.
Hope all this helps.
The Neuron

[cncadmin]

Prices seen a bit high, what is the tube life hours?

[coleong]

Hi mononeuron,

What type of money transfer are you using?

Normally i use TT (telegraphic transfer) or Western union.
TT for me is far cheaper than western union, that's at about one third the bank charges.
So far nobody complain about the bank charges on the receiving side (supplier).

[MonoNeuron]

Paul, The hours specified are 10,000 but in reality, from what I have been reading about glass tube lasers in general you won't get more than 1,500 useable hours out of any glass tube laser. It probably only has 1 watt power after 10,000 hours as the gas composition breaks down. I would like to get some feedback from someone who has had these things for a while and what sort of longevity they had. Hopefully not the sort of experience you are having now.

Celeong, I used a direct International money transfer from my bank to Mr Xu's. I tried a Western Union money transfer when I wanted some Pixie servo driver boards but I would now be an amputee if the transfer went through. They charge an Arm and a Leg for their services. The telegraphic transfer you talk about? is it made at the Post Office? I hope Mr Xu can get PayPal or some other means for his income from overseas.

[coleong]

Hi mononeuron,

In my country i can make a choice from TT (telegraphic transfer), Demand draft and Payment order from any bank.

I believe you could have send him a cheque (demand draft as in my country).
The receiver will have to pay some bank charges to collect the money that you have send.

Talking about Western union, the good thing is that you can send your money even to a "xxx" person. Not much identification is needed to send or receive the money......the bad thing is that you are right about the amputee issue if you have no choice but to use it.

[signbloke]

Hi Mononeuron
I read with interest you details re the supplier in China for glass laser tubes, i have been trying to locate an alternative supplier in China as the logistics of receiving tubes in one piece and educating my supplier about the fine art of proper packaging are bloody tiresome! In my expeience having run our 80w laser for 1 year now, glass tubes if used daily will pretty much only have a usefullness of 3-4 months tops, i am budgeting to use 3 tubes per year.
Have you purchased from the site you mentioned, if so is the service and supply acceptable?
Cheers
Ronnie

[ImanCarrot]

Wow! hold on chucking it away. The major reason lasers fail is the gas inside them eventualy escapes. Get it regassed (do NOT fly it out cos changes in air pressure can cause it to lose gas faster) or get a regassing kit. I had a similar problem with CO2 lasers... keps on dropping off as they were flying across the planet.

Re- gas it! it'll work.

[signbloke]

Imancarrot
Interesting, unfortunately i am not aware of any facility here in Australia for the regass of laser tubes, if any one knows different please post some info, i am guessing though that the cost of regassing will be prohibitive, these chinese tubes are pretty cheap. I have been flying them out with DHL, i am struggling to understand how aircraft pressure could have a negative effect though, considering that the tubes are sealed and airtight, if they could be damaged by pressure the i would have thought that the tube would have been faulty in the first place, if a laser tube has even the minutest leak it just will not function properly at all. 3 tubes a year is something i can cope with, at a cost of around $360.00USD ea + freight, this can be amortised as a consumable expense for the machine and covered in my hourly rate for cutting. My main concern is the packaging ex china, i am soon to place an order for 3 tubes from my supplier, unless i can find a new one.

Cheers all
Ronnie

[coleong]

Hi signbloke,

360usd for your 80w tube is a good price for testing and experiment.

You are saying it last for about 4 months, basically how many hours it is "on" and is it a full 80w power all the time when it is in operation.

When your laser tube fails, what is the problem eg. laser power is too low cause by the output coupler is darken or is it the electrode worn off?

May i know what is the length of your tube and who is your supplier?

Thanks
coleong

[signbloke]

Gidday Colelong

Price i mentioned is if i buy 3 minimum, tube length is 1600mm x 60mm dia. But i have not much faith in the packaging and i will be lucky if 3 tubes arrive here intact.I have located a manufacturer of glass tubes in the U.S and their tubes would be suitable, and guaranteed to maintain full power for at least 15 months, but the downside is that they are about $4500.00USD ea.
The laser is used for cutting most every day on acrylic sheet up to 12mm thick, and a lot of thin carboard for stencils. I was told that the gas eventually becomes used up by the normal operation and this is how the tubes lose power, i have probably 3 tubes in storage that are exhausted, although they will still cut they do not produce much power, ok for cutting the carboard stencils i guess.I am only storing them because i just do not want to throw them away in case i can find someone here who can regass them.
You mentioned if the output coupler is darkened, i would have to say yes it is on the old tubes, does this have an effect on output? how does this occur is it overheating?
I generally run the power at between 10mA to 25mA.

Cheers
Ronnie

[MonoNeuron]

Hi Signbloke,
I ordered a power supply from Xu Haixang (AKA HKXY) and his emails to and from me were excelent. He had an interuption in his services with the undersea cable being broken due to earth movement around Xmas time but was only out of service for about 5 days.
He is a bit hard to understand at times and if he knows he can't get his ideas across he sends an email with pictures then numbers all the relevent bits you request. I think he has a student translate for him as emails got better overnight. AS for tube packaging I cannot answer that as I haven't bought one yet but his packaging on the power supply was just fine. He seems to be going out of his way to let everyone know of the very average dealers in China and warns from buying cheap brands as Paul the site owner has attested to. I nearly bought from Steve Lou as well as their website says they are ISO ##### certified. Not true as Paul found out. I bought my tube from PK Unlimited on one of their Ebay auctions but it says 10K to 12 K hours on the tube. Maybe if you want a neon light after 1 year that would probably be true and I will find out in a few months when I get it up and running.
Xu says he only sells the better brand of tube and it does cost a bit more but you get a much better life out of it and after you buy from him then you get nearly a 40 -45% discount on subsequent ones (you can check on his website) I will buy my next one from him and try them out.
I asked him if I can open the power supply and photograph the insides and also the tube and then post the pics here and he says "no worries" and would like for me to do that. he says he is trying to build a better relationship with people outside China as there are a lot of ripoffs there that he wants to expose. I wish him the best of luck. lasers are a secondary buisness for him with the main one being his kit models.
I have no idea if he is like all the others out there that promise the world and deliver an island but he seem a very affable guy to me judging from his emails. I say give him a shot......What can go wrong ?????????
Richard.

[coleong]

Hi signbloke,

As far as i know it is true that the laser gas will degenerate over time.

If the output coupler gets darker, most probably it is from the fumes that attached to it while using - that's what i presume.
This will affect the output coupler lifespan as it will be damaged from the laser beam (heat) on the long term.

Maybe if you can try to clean one of the "worst condition tube's" output coupler with aceton and test it the cutting improves.
Make sure there is no residue remains on the output coupler after cleaning.

4500usd is a lot of money for 15months - approx 300usd per month or maybe less so i presume the chinese tube is still cheaper.

Maybe one day i will get a cheap air fare to china to bring back the tube and also have a visit / tour.

best regards
coleong

[MonoNeuron]

Hey SignBloke,
Just had a thought. Linde gas has bottled laser gas for sale. I don't know the quality of it or even if it is for a flowing gas laser but you may be able to give it a shot. Then all you need is someone willing to make a hole in your tube, keep out the air, then fill with just the right amount of gas and pressure then seal it all up again making sure the lenses wern't moved in the process.
Mmmmm, might be cheaper and easier to buy a new one !!!
Just a thought though and may be worth looking into.
The Neuron

[KTP]

"keep out the air, then fill with just the right amount of gas and pressure then seal it all up again making sure the lenses wern't moved in the process."

You just listed three things that are quite difficult to accomplish without equipment that will cost a good deal more than several laser tubes.

I have tried filling up a small rf excited 20 watt laser but only managed to get around 7 watts for a few hours before it needed refilling. I blame this on not knowing the gas mix/pressure and not processing the tube like was done when it was first made (I think they fill it with a mixture of oxygen/helium or something and ionize it for 24 hours). Also, lots of lasers use Xenon, but a bottle of that will set you back hundreds of $$.

[MonoNeuron]

Hi KPT,
I did a great deal of research into the gases and have come to the conclusion that it is way cheaper to buy the tubes. Flowing gas lasers don't interest me as I hate waste and the cost of the rent on a gas bottle here is as much as the contents and the only way you can build a laser at home is by using flowing gas without knowing the active constituents.
I ended up buying a glass laser tube. It's a shame the manufacturers don't have a return policy as it seems a waste of glass tubing and mirrors to just let the thing die of natural causes and then throw it out. As I said before, I hate waste. I get into trouble at work for not throwing stuff out that I think could be used again or refurbished but sometimes I have to bite the bullet when everyone gangs up on me and calls me "Steptoe" from the TV series.

[jinweike]

You had better cover insurace for the laser tube or laser machine.
The tube is fragil. If you get a bad tube, you can ask for claim from the insurace company

[jinweike]

If it is the problem of the laser tube, there is no light from the tube , the seller should send you one laser tube for replacement during warranty time . We also sell laser engraving/cutting machines, we can offer good after-sale service for our customers.

[Laser Doctor]

Here is a bad laser tube


http://cnczone.com/downloads/laser.wmv

Dear Paul:

This tube shows classis signs of a poor gas mixture. It also appears to be a high concentration of O2 which is bad for any tube. Because the mixture is so poor you have burned the anode which has caused the darkening. We also refer to it as Electron Jumping.

The Laser Doctor

[cncadmin]

That makes total sense!