eBay K40 CO2 Laser - Step by Step Guide To Replace a CO2 Laser Tube!

In this episode, we will be showing Step by Step how to replace your eBay / k40 40 watt CO2 laser tube! Please be sure to watch the complete video as well as read all of the notes below BEFORE starting!
The first step is to source a replacement tube and we did a lot of home work to find the best price to quality as many vendors wanted almost the price of a complete new machine just for the tube, or some of the cheaper ones were known to ship poor quality or even broken tubes. Here for just over $100 USD with free shipping (at the time of this video) we found this vendor and we have also had good luck with purchasing via Amazon vendors over other third parties in case a return is required: diy3dtech.com/40watt_co2_laser...
Additionally, we also suggest replacing the silicone tubing too as it can degrade over time and it can be affordably sourced here: diy3dtech.com/silicone_tube_co...
To insulate the anode and cathode we used a high grade silicone adhesive (do NOT use the cheap stuff or household variety): amzn.to/2OYJNes
Of course safety is a big concern and if you undertake this project please understand accept this at your own risk and there should be several initial steps taken:
1. Unplug the machine from mains voltage.
2. Drain laser tube of water as best as possible
3. Ensure the high voltage power supply is discharged (see video)
Care should also be taken NOT to break the old tube and especially the new one as they are VERY fragile! This also required increased care when swapping or replacing the silicone cooling tubes.
Replacement of the Zip-Strips, you will notice I did not replace the Zip-Strips (cable ties to some) at the end this is because they "appeared" to be used for transport so the wires did not come loose during shipping. Since this was not the case for use we felt is was not worth the risk to the tube re-apply these as everything you do that tube risks a crack and is very fragile.
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[@Kevin-tc3ob]

I am really glad i watched your video BEFORE reconnecting my tube as at first I thought - ohh, that wiring can't be safe just wrapped around and not soldered! Thumbs up & subbed!

[@bawballs]

A great helpful and clear tutorial. Thank you for giving me the knowledge on how to change my tube.

[@sotm2]

Dawn dishwashing soap works fantastic to lube the silicone tubing to get on the new tube!

[@nickm324]

Using the link for the replacement tubing, which one did you buy, there are like 20 different sizes? its seems to be set to the 8x12mm tubing in a 2 meter length.

[@deonbroodryk4404]

Thank you for the vid

[@jean-marienoyes9918]

Description step by step you dream my boy !

[@kingdavid1227]

so you can just use Astroglide to get the tubes on?

[@blackantler_9thr430]

Hey brother great video thanx for the tips. Had a question though, see I tried to order a bulb an the sent it with the wires attached and I need a bulb like the one you have in the video but ever time I go to the link in your page it just sends me back to your shop page can you please help me get to the link you got your bulb from. I got one from Amazon before but can't seem to find it. Any help would be greatly appreciated 🙏

[@fabsproductions1]

The cap where the water runs through fell off. How can I glue it back on ?

[@carolemattia7867]

how do you open the back??? no one shows that I can't get mine open HELP

[@dwightstebner2345]

why does no one show direction of water travel through tube?

[@woogaloo]

What is the camera that you have inside the laser bed area? Does it help w/ aligning to a workpiece?

[@DIY3DTECHcom]

Just to watch what is happening when the lid is closed.

[@MentaPrints]

wait is this...This Old Tony?

[@pkarza]

Is there any way of identifying the anode from the cathode end?

[@DIY3DTECHcom]

Yes the anode is large red wire and the cathode a small blue wire going to the ground...

[@1010tesla]

shouldn't the coolant output tube be at the 12:00 position to ensure no air is trapped at the output end of the tube?

[@DIY3DTECHcom]

Thanks for commenting, the configuration as it sets work without bubbles. Worth note is you should have enough pressure / flow to prevent bubble. If you get a bubble just tip the machine slightly and it will pass. However again if you have enough pressure / flow, you will not get bubbles as they will be pushed though...

[@matchstickdesignco]

Did you have to pay an additional 25% customs duty since it came from China? Or did the sender under-value it on the customs forms?

[@DIY3DTECHcom]

I purchased it from Amazon here: diy3dtech.com/40watt_co2_laser_tube so no issues...

[@SarbarMultimedia]

Hi All Please be aware that KHLaser (despite what the label says) do NOT manufacture tubes. Instead, they purchase main factory rejects at scrap prices , retest them to make sure they funtion "in some way". They then relabel then to give the tubes credability. If the internal mirrors are slightly misaligned from perfect during manufacture, the power will be down and there is no rectification possible. If you want to see what you have bought there is a very simple test you can perform using a block of acrylic. see kzbin.info/www/bejne/pJKzq3mpqtuIiLc A very pointed burn =A grade and a blunt burn= B grade

[@tenlittleindians]

How do these wear out? I see a glass tube with a couple of connectors and a mirror on each end, what wears out?

[@DIY3DTECHcom]

The gas both seeps out as well as converts from CO2 to Nitrogen with use because laser tube consists of around 10-20% carbon dioxide (CO2), around 10-20% nitrogen (N2), a few percent hydrogen (H2) and/or xenon (Xe), and the remainder of the gas mixture helium (He). Also it is worth note, the high current you use the faster the tube will wear out. Depending on your usage level, you will likely 2 to 3 years of reasonable performance...

[@tenlittleindians]

@@DIY3DTECHcom They recharge neon sign gas tubes so why not recharge co2 laser gas tubes? The gas is cheap.

[@user240485]

@@tenlittleindians I think is more of where to get it refilled. Fairly sure they use a exact formula of gases that neon shops might not have available. (Edit: I meant the mixture not the gases themselves, pretty sure they don't mix gases on site themselves) Not to mention that not everyone has a neon shop within reasonable distance. Finally I'm guessing it a matter of cost, quick check on ebay says they are about $100. While not cheap its not hugely expensive. And it easy enough to just order one and be done with it. While finding a neon shop and traveling to one then dropping it off to get it serviced will probably cost you the same if not more. The gas is cheap but they are selling you their service not the gas. Expect to pay the same amount that they bill businesses.

[@sotm2]

Your link for laser tube does NOT carry a 40 watt tube!! What did you use? anything bigger than 40 watt is too long for the cabinet!!!

[@sotm2]

Outlet tube should be at 1200 high noon position not horizontal!!

[@3dtexan890]

I take it the the tube you replaced went bad?

[@DIY3DTECHcom]

Yes it was about three years old and was under performing. It served me well...

[@user240485]

@@DIY3DTECHcom which is honestly not bad. I have heard of people over charging the tube and not following the recommend amperage and burning them out early. But never heard the approximate lifespan for average use. I haven't nearly used mine as much as you so its nice to know I could expect mine for years to come.

[@GeorgeZaharia]

everybody saying high quality silicone... but is it just regular 1000 degrees Celsius silicone ? or dielectric silicon? or glass/ ceramic silicon... i tried butyl tape which is rubber basically with a 7000V rating on 1 turn and used 3 turns on the caps and still got shocked back to childhood memories... problem is even if the butyl tape is electrically resistant... current for starting the tube is 14kV double whatever the tape can hold... now that silicone... and piece of 8mm silicone hose it comes with over the silicone from manufacturer is it smth special? cause i tried all arrangements and i keep getting zapped like the Doc in back to the future... i think il start a youtube channel and give a run for the money to electricboom cause at this point im getting zapped more then electroman from spider-man.

[@DraveS21]

i came here to watch how to wire HV to tube and this is skipped XD

[@el737rs]

Heh... First viewer... Hopefully won't be needing this guide any time soon :)

[@DIY3DTECHcom]

But when you do, this video will still be here! :-)

[@DavidinEssexUK]

Now for the miserable job of aligning the mirrors.

[@DIY3DTECHcom]

UG! Yes your right! However I created this way back to assist: kzbin.info/www/bejne/gqSzp6utadxgitE

[@darkflux]

so you didn't bother filming how you connected the tubing, the wiring, or the clamps...what was the point of making a video? i mean, ANYBODY can see WHERE things are connected if they own one of these...

[@mingleSTREET]

I honestly have no clue what this machine does...

[@DIY3DTECHcom]

It makes a very bright light which you can not see and will cut things...

[@sotm2]

Don't think this advice is very accurate!

[@jppalm3944]

Ebay? Watch the news. Scary. Company