Need Help!- Output coupler leaking

[piranah]

I used hydrochloric acid to clean out the tube and now the output coupler is leaking. Do I need a new tube or can I just replace the coupler or reseal it or something? Thanks!

[bpoulin]

A. Why did you use hydrochloric acid to clean it?
B. Did you get any on the hose? Most hoses are rubber, vinyl or neoprene. All 3 I believe will be eaten by any trace of HCl. Also any rubber seals in the pump, or flow sensor will be eaten up... I would try replacing the hoses first before the tube. Not to mention it will eat just about any metal, so if you have a chiller... Not good.

Here is a link to what is compatible with HCl and what is not. Cole-Parmer: Compatibility Results

P.S. is this a glass tube?

[piranah]

Some metal nuts had fallen into the water and accumulated rust, the tube had scale in it. I searched online and came across this that says use a diluted mixture - CO2 Laser Tube (18W-100W) - China Laser Tube,Co2 Laser Tube,Co2 Laser in Engraving & Etching Machine

On the plus side the tube is completely clean now I'm able to run the water through the tube without a leak by detaching the small hose that goes to the coupler and running directly to the tube. I'm wondering how hot the coupler will get, can I run it without cooling the coupler? Yes, it is a glass tube. I saw some places that will replace the output coupler, does the gas have to be recharged?

[bpoulin]

Once the CO2 is out you're done, you need a new tube. I thought it was a coolant leak. In the future keep your nuts out of the water... Sorry couldn't pass on a good pun...

[piranah]

No, it still works, the gas is not leaking. Only the coolant is leaking around the coupler. I detached the coolant from the coupler and the laser is working. I'm just wondering:

A: If I replace the coupler / cooler assembly will the gas need to be recharged?
B: How long can it cut before the coupler overheats?

[bpoulin]

Ok can't help you there, I haven't been through that, hopefully someone else can chime in.

[geekinesis]

Hi

It will overheat within a few seconds without cooling. The tube is working but I imagine it wont for long as once the seal on the coupling is broken, gass will be leaking, even if its very slow.

[Tweakie]

You must use the cooling jacket on the OC - do not run the tube without it.
These appear to be fixed / sealed with epoxy so clean up the area in question and apply epoxy as necessary to effect a good seal.
If a tube overheats the epoxy holding the mirrors softens and the internal gasses can be compromised, lets hope this has not happened in your case and all will be well.

Tweakie.

[piranah]

Thanks for the feedback so far. I've been able to use it for a few minutes here and there and the coupler hasn't gotten that hot. I'm wondering if I can somehow reseal the coupler - put some fix-a-flat through... Or clamp on an external metal coolant fixture.

[Tweakie]

Risky to clamp anything to the tube, differential expansion and all that, best to use epoxy.

Tweakie.