SP168 in hospital - moved thread

[Laserman532]

Interesting, very interesting- I love whats left of my glass sp equipment-
I have 20 year old plus 171 argon tubes which still deliever about 22 watts-

Brian at Cambridge is a class act- I haven't had any refurbs since the ion market tanked-
I have enough Coherent's to get me by..

I have dealt with water jacket leaks/cracks using gasket sealer- with good results- LOL- what do you do when it has to work right?

So do tell laserman- does the liquid co2 trick work on overpressure units? ( quartz reservoir submersed- then actuator opened? )

How about the 2000hr power supply service shutdown on the "second" generation units-?

I have done my share of sailing- might have to re-visit those tubes with the sacaraficial anode
technique- kewl..!


peace

co2 trick, never tried it i heard that it "could" work- to bring down the pressure in a PT we would hook a car battery across the across the cathode wires, cathode would start to glow then "flash,flash,flash" un hook battery and you will shave off 10 to 15 volts each time. As a service engineer we would try this first for no start tubes especially when the customer would be agressive and not wait between fill cycles. I have removed many a car battery from rental cars during service calls.

Microprocessor controlled lasers? (with any logo on them)?? I wouldnt doubt it one bit (cant say for many reasons) but I wouldnt doubt it ONE BIT! Our service department was VERY PROFITABLE!

Sacraficial anode- most lasers you will find will have the mod already done. it was usually a white hose (between magnet and glass water in stem on pt) with a small red wire going to the anode. Vastly increased the lifetimes of the glass to metal seal at the anode end.

[Laserman532]

Hi Ritchie

I dropped them an email and Graham replied. I wasnt expecting it to be cheap but the best he can offer is a complete umbilical and lets just say I wont be buying one! Back to making one

Pat

Tufnol is a brown flakey/brittle (ish) synthetic resin bonded fabric which is good to mill, turn, or tap. Its often used for connector insulators - Im sure you have come across it at some point though I guess not under that name. Its often in sheet form of several mm thick and I think is also availabe in rod and tube form. On first glance - without close examination this is what I would have said the slices were made of. People often incorrectly refer to it as bakelite - which as far as I know is far more brittle than tufnol. The actual connector insulators have an almost graphite look to the surface - sort of mettalic loaded look though for obvious resons I know that is not the case
As for anode leak - no Ive not tested yet for 2 reasons. Firstly until yesterday the head was still in my transport crate and so isnt hooked up to the water supply, and secondly because the problem with the connector is priority at the moment. I understand how important it is I check this and will do later in the week when I get a chance and certainly before I try to put power back on. Unfortunately work has a bad habit of getting in the way of lasers and taking up my time!
Will report back when I have hooked it up and pumped water through the head.

Rob

ROB- THIS IS GOING TO BE A STRETCH HERE. if you can, find the material, program the pin layout for machining, and contact Amphenol for the pins you might have a product there to sell to Graham.

Big stretch- maby amphenol still has plans, drawings, or even a couple in their dusty old stockroom. Might be worth a phone call.

Just talked to Brian at cambridge and he needs to honor his relationship with graham as his distributor

IF I WERE YOU. I would buy an old laser from a university with a bad PT and keep it around for spare parts...but that is what I would do

[Laserman532]

[IMG]file:///C:/DOCUME%7E1/ADMINI%7E1/LOCALS%7E1/Temp/moz-screenshot.jpg[/IMG]http://cgi.ebay.com/SPECTRA-PHYSICS-164-ION-LASER-265-POWER-SUPPLY-EXCITER_W0QQitemZ250182707821QQihZ015QQcategoryZ10 9452QQrdZ1QQssPageNameZWD1VQQtrksidZp1638.m118.l12 47QQcmdZViewItem


Look closely and you will see the sacraficail anode mod...this one is orange (light red?) some were orange some where white.

This laser has problems seller is not disclosing. Output mirror asembley is missing, output bellows assembly is missing. AND PT appears to bu up to water look at anode shot. water appears to be in the brewster window.

I would offer him 1k just for the parts- PT looks bad to me, but without more careful pictures one cant tell for sure

[Laserman532]

Link didnt work, here is the item number
250182707821

[mliptack]

http://cgi.ebay.com/SPECTRA-PHYSICS-164-ION-LASER-265-POWER-SUPPLY-EXCITER_W0QQitemZ250182707821QQihZ015QQcategoryZ10 9452QQrdZ1QQssPageNameZWD1VQQtrksidZp1638.m118.l12 47QQcmdZViewItem

[stanwax]

Pat - and all see pix for anode mod - I assume this is what you mean.

Pic 1 showing where red wire attaches to the anode.
Pic 2 showing the red wire into the hose between the tube stub and magnet jacket

As for making them to sell to graham yes neat idea....
I had already looked up amphenol with a view to asking - after all if you dont ask you dont get! I respect what Brian said about Graham but obviously a little disapointed. Graham has parts to sell me but for too much money for a hobbyist. I can afford to buy off him I just would rather buy something else for that kinda money. If it was in an installation earning money it would be a different story...
As for buying an old head - I have kept half an ear to the ground for a while but I guess I would need to be proactive and go searching knocking on doors & ringing some phones.

Thanks again for all your input.

Rob

[Laserman532]

Pat - and all see pix for anode mod - I assume this is what you mean.

Pic 1 showing where red wire attaches to the anode.
Pic 2 showing the red wire into the hose between the tube stub and magnet jacket

As for making them to sell to graham yes neat idea....
I had already looked up amphenol with a view to asking - after all if you dont ask you dont get! I respect what Brian said about Graham but obviously a little disapointed. Graham has parts to sell me but for too much money for a hobbyist. I can afford to buy off him I just would rather buy something else for that kinda money. If it was in an installation earning money it would be a different story...
As for buying an old head - I have kept half an ear to the ground for a while but I guess I would need to be proactive and go searching knocking on doors & ringing some phones.

Thanks again for all your input.

Rob

Yes thats it and you have it. So i bet you are good there. Is that your laser??? IF so it looks real nice, i wish you would have shot between the anode and magnet (sometimes you can see a water stain if your o-ring has been leaking) but after seeing the condition of your head...all looks good in there mate.

Do you ship with the bellows unscrewed like that? I recommend loose...not completely unscrewed (parts rattle too much) If you get a chance shoot me a pic of the top of the cathode. All in all thats a pretty clean machine ya got there!

Brian mentioned a "couple hundred dollars" what did Graham say???

[buffo]

Hey guys - It might not be pretty, but is there anything stopping you from making your own connector? IE: just trash the existing socket on the head and cut off the plug on the end of the cord... Now use a different (and presumably cheaper) commercially available plug and socket (or several sets of plugs and sockets) to re-wire the whole thing.

It won't be factory, but as long as it insulates properly, what's the problem? (Maybe use Alden plugs for the Anode and Cathode due to the HV starting pulse, but the rest of the voltages should be less than 200V, which is easy to work with...) Gotta be mindful of the current limits - but even so I'm sure there are connectors available that will do the job.

I ran into this problem with a Spectra-Physics 163 head and 261B power supply. The PSU used these obsolete "Jones" style plugs that were impossible to find, so I re-wired everything. (Though, admittedly, in that case I chose to link the head to the PSU permanently, so I didn't have to go scouting around for a replacement connector.) Still, I think this might end up saving you money vs. buying a several hundred dollar cable end connector!

Adam

[stanwax]

pictures - we got pictures
not of what you want between anode and magnet but cathode cold, filament up and plasma up - and another action shot to get you all excited

enjoy

Graham said £750+17.5% hell the whole lot only cost me a little more.....

The stem seals were off at this time as I was aligning and I am paranoid about snapping the stems when searching with the ends. I had also cleaned the brewsters and mirrors - thought I would go the whole hog and didnt close them back off till it was aligned. I built me a little rig to raise and lower my 7mW uniphase hene so I can fire it down the bore of the 168. I used 4mm stud and the bearings from some old cpu fans as thrust bearings in the feet. Worked a bloody treat. Have used this setup twice to do a from scratch alignment.

as for clean - yes its good - I was told it had low hours on it - but they all say that but it had the cambridge refurb in Jan '96 and has only done some hours really since I got it and Ive probably only put about 150 hours on it if that!

Rob

[stanwax]

Hi Adam

Yes that is a thought - the anode needs to hold up to 220ish volts give or take and 35A the only real one as you say is the start pulse and keeping that to its designated pathways.

Im still up for machining my own insulators for the existing con. I just need to select my material and get some in, though I will contact Amphenol in the mean time and see if they have any hidden away in the depths.....

Rob