Yongli tubes?

[Mike Lysov]

Hi guys,

It seems I am going with a DLT-280 combined tube from Yongli which has just two separate glass tubes and a combiner enclosed in a metal case. It should replace my two GSI tubes. One of which is dead and the other giving me 125W instead of 140W.

I do not expect anyone here to have a laser with a DLT-280 tube and share their opinion on this exact model but I hope some of you may have just a single DC glass tube made by Yongli and can share their opinion about their tube.

There are no much reviews about Yongli on the Internet. I have seen one member here saying they switched to Yongli because RECI started to supply bad tubes but this is just about all I could find.

[Doug Fisher]

There are a lot of fake RECI tubes being sold these days.

[Dave Sheldrake]

Mid to lower quality, Yongli, not a tube make I would use by choice

[Mike Lysov]

The problem is that I do not have too many choices.
RECI and SPT do not reply to my emails regarding linear polarization on their tubes so I am not sure if their tube beams can be combined into one.
There are some traces on the internet for their specs that their tubes have reasonably linear polarization but it cannot be found on their websites.

And repairing my GSI tubes solves the problem for now but when they are dead again I may not be able to repair them and I will be looking for replacement again. So I think it is better to find replacement now than delay it for a few years. Plus if I buy a new tube before the end of this month I should get almost half of this tube price back as a refund in taxes that I have paid already for this year.

[Dave Sheldrake]

Problem will be Mike if one of the two tubes dies, getting it all re-aligned will be a nightmare, at the factory or on a bench it's pretty easy if you have the kit (I do) but on a wing and a prayer it's almost impossible to combine two tubes of unknown polar depth without knowing the exact details of the polarisation and where to phase stack

[Mike Lysov]

Dave may be I am wrong but I have to do all this with my GSI tubes too. I am not sure about terms you are using but first I need to rotate one tube watching how much combined power shown on a power meter. When it reaches maximum combined power it is done.

With GSI tubes it should be that one tube set fixed in its brackets and the other one set loose and needs to be rotated 90 degrees to the other. You cannot simply turn it 90 degrees by just looking at it as there is almost no point of reference how much you have rotated the second tube in relation to the first one. That where my Gentec power meter comes handy. I believe that what you call phase stacking.

Once it is done and the seond tube is fixed in its brackets I have to manually align two beams by adjusting mirrors responsible for near and far field alignment. That's what I would call two beams alignment. I can say that this last step is the hardest but it can be done. At least I have done three times because I have moved my house and business two times in the last two years plus I did it once or two times when I got this machine.

With the Younli tube at least all this is set up initially so it will be much easier for me to start. The only worry is how long they will last and that's my biggest concern. my GSI tube was dead after 2000h. So unless it is a water chiller problem and my laser manufacturer has given me much smaller unit than it should be it seems that GSI tubes are not worth $6000 they were asking for them.

In the last few days I have found three used Synrad tubes 200W Evolution(model # 57-2) and one Coherent K-300. Their owners are asking for under $7000 for a set before shipping for their Evo tube and $10000 for K-300. I was considering them too. However there is a huge risk I will get something near death plus it has turned out they all need 3-phase power. I have no idea how much it will cost me to add 3 phase to my existing house considering all my electrical wiring are underground. It could be the same price as for any of these tubes.
Actually I have found two more evo tubes (one more # 57-2 and the other is 60-2) but their owners want $15K for each.


I am still thinking about these Synrad and Coherent tubes but it is most likely I am back to two options:

1)repairing GSI tubes through the guys you have recommended, If they do their job right I am back to original power of these tubes and it will be the least expensive option. However it will take 7-10 weeks with two shipping plus there is still no chance to say how long they will last after repair/regass.
2)buying Yongli tube and hopping it will last at least 3000 hours.

I probably should repair GSI tubes anyway as they cost more fixed and re gassed rather than trying to sell one dead tube and one dying tube. However I still want to get the best option to keep that laser running for my business at full possible power.

I have increased my budget to almost $10K USD for a replacement and I still cannot find anything reliable. That's alone driving me crazy.

[Dave Sheldrake]

Phase stacking is different, if you fire two lasers at a power meter , say 2 x 80 watt tubes you will get a reading of 160 watts, that doesn't mean the beams are combined though.

A GSI should last easily 10,000 to 15,000 hours (My SLC 200 has over 10,000 hours on it) I'd suggest you have chiller problems, anything over a stable 23 degree's C will start killing the tube life, each degree above and it's becomes almost exponential.

For a twin GSI 140 set up you would be looking at a CW6000 or a CW6200 chiller,figure on spending $1,500 to $2,000 to chill a tube set like that.

The 57-2 tube is pretty good, reliable and usually fine out to 15,000 hours or so, re-gas isn't cheap but still manageable. Remember, a decent 200 watt Evo will outclass a twin 140 setup by quite a bit, the beam profile is far superior even when it's a DC GSI tube set.

I think Millenium give you a years warranty on the pipes, so pretty good.

You can refil them yourself (I have the kit to do it) but to be honest it's a pain and getting the mix right is an even bigger headache (I have all the gasses for use on the Industrials so messing with normal DC tubes can be fun)

[Mike Lysov]

I have never run my chiller with water warmer than 20 degrees. Normally it was set to keep water temperature 18 degrees or below. However with my last water refill I only filled the chiller tank slightly above minimum level. Or may be I filled it close to maximum but a lot of water evaporated during hot days. It is really hot in Brisbane for 5-6 months.
When both tubes were ok I could see a lot of bubles rushing down the tubes on every chiller start but all bubles were gone in 10-15 seconds after the chiller started and by the time I fired the laser. I just though it is normal to have bubles and I did not worry about them especially because they were gone in seconds. I filled the chiller with water level siting just a bit below its maximum level a few days ago and there are no bubles now but it is kind of too late for me :-)

The guys are providing warranty but when you are 15000 km away and parts are huge, heavy and made of glass it is almost pointless.

I am still considering sending the tubes to them but I have only one original box from JKLaser and I want to send them both tubes. It can be kind of tricky. If they are broken in transit insurance can refuse to pay for them on the fact that I packed two tubes in a box that supposed to take one tube only.
JKlaser always wanted to have 10cm clearance space from each side of the box to the tube. They have a sticker inside the box that explains it. And with two tubes inside it will be like 6cm from sides and 6cm between the tubes.

As for the refill kit, where I can get one? If it is not expensive I may try to do it yourself if this kit is not expensive.

regarding dlt-280. There is one thing that never crossed my mind until now. If all Chinese tubes come with random polarization, how Youngli combining two glass tubes output inside his case? If he produces some tubes with linear polarization then I can just buy these tubes and combine them using optics I have.

To be honest I used all search engines to find DC exited glass tube with linear polarization. I could not find any at all. Even JKLaser tubes are not showing on the search result. It is strange as their PDF file for their Eco DC exited tubes says that these tubes come with linear polarization.


I have one offer from 57-2 tube owner and they want $6500. It even includes quite powerfull chiller. But looking at the specs these guys sent to me they run it from 3ph power. I do not have it and adding it to my house can cost me a few thousands.

May be USA members can look at the specs below and tell me if it is 3ph or a single one. I can see the chiller runs from 3ph but Poe control says it is 300-400VAC

Manufacturer: Synrad
Model: E200S
Product Code: 220212
Electrical: 30V
Includes TAEevo 015 Chiller: S/N 220 059 377, (Electrical: 400V, 3 PH, 60Hz, 8.5 Amps)
Includes (2) Model RF3000 Power Supplies
Includes (2) Model SQ1506-3F-400-500-AL-DD Power Controls: (Electrical: 400-500VAC, 50/60Hz, 4.5 Amps)

That's probably the cheapest 200W RF on the market but whether I can use it or not on a single phase 230V circuit I have no idea.

[Mike Lysov]

I have found the manual for the 57-2 and it says that it needs 130A at 30VDC. That's 3.9KW and if I understand electricity a bit on 230VAC I need only about 17A. Is it correct?

I guess it sounds right and it explains why this tube needs two DC PS 2000W each.

Does anybody know how much an internal DC-2000 power supply from Synrad cost? I will need two of them. Or can I just buy any 2000W DC with 30V output?

I have another guy who wants to sell his(or probably resale some else's) 57-2 as a complete set. I have found him on ebay. But he is asking more than other plus shipping through him is almost $1700.

[Dave Sheldrake]

Figure on a filling kit being about $3,000 + gasses, plus you need to add the fill valves to the tubes (at the full reflector end)
The electrical input side I can't really help will (Bill George?) as I have 3 phase anyhows for the bigger machines

You can combine any DC tube, it's getting the phase stack right that causes the problems, DC tubes in general are "mostly" linear polar, it will depend what your mirror is though, most firsts are 1/4 or 8th phase retarders.The thing to avoid is the cancellation effect (one beam in effect kills the other) it's even possible to badly stack two 100 watt tubes and end up with a null output (perfect cancellation) although outside of a lab it's VERY hard to do.

I built a couple of combined units for fun, but I do have a wave front analyser so that made it a lot easier, for a 150 watt unit they start at around $7k for a basic model and go upwards

I think it's Yongli that do a refil kit...Mine is a Mitsubishi but Yongli do refillable tubes from memory?

[Mike Lysov]

Thank you Dave. It sounds complicated with the refill kit. What does this kit usually called?

As for the RF tube I sent all details to my electrical guru who is by the way is very knowledgeable with everything related to CNC. He looked at configfiles and cnc code generated by my system and he said there would be no way he could help me with integrating the RF tube into my system. So If I do not get any help from the guys who built my laser I will have to drop that idea.

So I am back to dlt-300 tube and repairing my GSI tubes. At least I can install either of them without any problems and knowledge in electrical stuff,
I am waiting for a reply from Yongli technicians to confirm if I can use my power supplies from GSI but it looks like I can. If I have to swap them then I will use my CNC guru to help me.

I have watched a lot of videos with DLT-280 cutting timber and it seems it matches what two GSI 140W tubes could do in terms of cutting speed. Since I am going to go with DLT-300 it may be even slightly better.

[Dave Sheldrake]

Lemme see what i can find Mike, the refil kits come with tanked gas at the right mix for CO2 DC tubes as well, a Vac pump and a monitor, you can even buy empty tubes ready built with the valve gear

Back in a bit

[Dave Sheldrake]

Dianman Laser


https://www.youtube.com/watch?v=_EjXaSnyATM

[Mike Lysov]

Thank you Dave. I will check with them later.

I have paid for the dlt-300 today. I just cannot spend all my time on all this research and I need my machine working again asap.

I will postpone adding a RF tube to that laser. May be in a year or two I will just replace all electronics in that machine and buy a controller that can work with a RF tube. I am pretty much sick with a level of support its manufacturer is willing to provide. Instead of answering my question about which Synrad tube will work with their machine with their help they they are just trying to sell me an upgrade kit with a new Synrad F201 for $35000. Told them many times that I cannot afford it and that's why I am looking for a used tube and just need their help to integrate 57-2.

If I replace everything leaving just motors it should unhook me from dealing with them again.

[Joseph Shawa]

I am going to try the built in red laser by SP Laser on my next order. Anyone have it yet? I'm still a few months out. Love their power supply.

[Dave Sheldrake]

I am going to try the built in red laser by SP Laser on my next order. Anyone have it yet? I'm still a few months out. Love their power supply.

True combining of multiple wavelengths always causes power loss, it's an effect of the combining that can't be avoided. I don't have red dots on any of my machines now, only one has a green combiner added and that was for demo purposes

[Joseph Shawa]

I believe it is emitted INSIDE the tube. So it isn't combined in the traditional way.

I too haven't been a fan of the red dot because it is always too bright and needs adjustment with different heights. But in the SP Laser it is a true indicator of where the beam is directed from what I gather. Makes beam alignment a cinch.

[Mike Lysov]

While I was looking for a replacement I found one glass tube that comes with a red laser integrated into a tube. I believe that was a tube made by SP lasers.