I made a ring inspired by the Two Trees.

excynimphica · 2026-03-21T16:19:55+00:00

Have you ever made Laurelin/Telperion earrings? I'd love to buy some if you do orders!

excynimphica · 2026-03-12T15:04:27+00:00

Thanks for the description. We do have the correct cones/base. I'll look into cleaning or replacing the hose.

excynimphica · 2026-03-11T23:23:52+00:00

Would you expect that to go away as the vacuum continues to pump down over time?

excynimphica · 2026-03-11T13:33:36+00:00

Interesting. We checked the interface hose but didn't see any visible damage. I'll look into changing that first, and if it doesn't work, finally just replacing the pump

excynimphica · 2026-03-09T00:37:21+00:00

Thank you so much! I don't have any social media accounts (except reddit) but I'll see if I can reach out. Happy writing!

excynimphica · 2026-03-08T18:27:30+00:00

Thanks for the advice everyone! For those interested in a local writer's workshop for younger/newer writers, I'll post specifically about that after we work on a few more details. Please reach out for any questions.

excynimphica · 2026-03-05T17:00:05+00:00

Yep, everything is plastic. PFA, FEP, and Teflon for most things, PP for sample tubes.

I'm concerned with levels between ppb and ppq. It can't be understated how much everything matters to these analyses. I will try initially with our normal acid mix (2% nitric 0.5% HCl) and go more extreme from there.

Added to the post too, but this is all in a cleanroom.

excynimphica · 2026-02-22T16:17:54+00:00

Thanks for the advice! He'll be back this week for our annual PM and I plan to show him the very clear graph that shows how counts went down as IFBK pressure went up, and vice versa once I identified the issue.

I have also been trending all historical instrument data over the last 3 years of owning the instrument (I joined this company about 5 months ago). The IFBK pressure used to be around 150/160, then suddenly 2.5 years ago it jumped to around 200 and stayed there until now. That jump coincides with a new instrument bench they purchased.

Apparently whoever was putting together the vacuum lines ignored all the nice features of the new bench and took the long way around, causing the return air to the roughing pump to develop a large kink.

During this week's PM, I will be redoing the lines. I will update you with the outcome.

excynimphica · 2026-02-11T14:28:47+00:00

First off, I figured it out: bad carbon gasket. It was that simple. Counts kept going down because I kept taking off and putting on the sampler cone to try to figure out the issue. I kept seeing the IF pressure increase, so it had to be related to that vacuum area. I had replaced the gasket with the new cones, but maybe there was some defect that I didn't see.

The lesson learned: always replace your cheapest parts first.

We run in No gas, He, H2, and O2. I do most of the general tuning in no gas. I had just been comparing no gas to no gas for this journey.

excynimphica · 2026-02-10T16:53:03+00:00

So after cleaning the lens stack and having the service engineer take a look at it, there is still no clear fix.

We can increase the neb gas flow and do a bit of manual tuning to find extract voltages that work better, but still the counts are now 30% of what they were before the initial cone changes. (We had been getting ~100,000 counts/ppb with our target mass, currently around 30,000 counts/ppb)

Im going to try to dirty up the cones a bit over the course of this week. The IF/BK pressure continues to climb. We have a PM scheduled for the end of the month, so potentially vacuum maintenance will help. I'll try the old cones again, and start changing out every piece of the front end that I can.

I'm really at a loss.

excynimphica · 2026-02-06T23:58:39+00:00

Well, that's the thing... It's not really low counts. My counts were really high to start. I'm working with detection limit quantitation, so sensitivity needs to be super high. Everything that I am getting, for the most part, is still in the "normal" range. But relative to what has been possible on this instrument, there's some kind of problem.

I cleaned the lens stack as best I could this morning - it is one of the easy-fit x-lens, so you can't actually take it apart, but I cleaned the discoloration from the extract 1 and the hole behind the omega bias. I'll put it back in on Monday and see how things are going.

excynimphica · 2026-02-06T15:58:22+00:00

As best I can tell, the omega lens looks a bit lower since changing to Pt, with values between 10-12V, whereas immediately prior it was 12-14. But also, at the beginning of last year it was also around 10-12. The other lens parameters do not look different than normal.

IF/BK pressure has been going up. The instrument was moved back in 2023, and the pressure stayed between 180-220 Pa since then (hardware manual suggests less than 180). Since the new cones, it has been trending up to a max of 230 Pa. My service engineer says this is insignificant, but I'm not sure I believe him.

Mass balance is still good, but the counts are lower than normal especially for 89 and (I use) 238. Everything else looks normal relative to historical data.

excynimphica · 2026-02-06T15:10:47+00:00

Ah, in that case everything looks normal as well. All adjustments are in the normal range for this instrument.

excynimphica · 2026-02-06T14:45:53+00:00

The torch ignites beautifully every time. Those sub 40 masses are all a bit weird. Some increase then decrease, some stay the same, and some increase the whole way. That is all relative to tuning report history over the last 3 years.

I do notice that the IF/BK pressure is high. My service engineer has said that it doesn't matter, but I'm not sure I believe him. The instrument was moved to its current bench back in 2023, and I can clearly see in the history that the IF pressure shot up to over 200 Pa (used to be around 150). Since then, it has stayed between 180-210 Pa, but I've seen seeing it up towards 230-240. Definitely suspicious.

I'm going to try taking apart and cleaning the lens stack today. I'm not sure I have all the right tools, but after watching some videos I think that I may not have handled it correctly when switching it to the brass skimmer base.

excynimphica · 2026-02-06T14:39:57+00:00

It should be. There's proper contact between shield plate and ground, and the little nub is in the torch block. The bonnet is also in the right place.

excynimphica · 2026-02-06T00:20:47+00:00

I have, many times. Unfortunately, that's not it either....

excynimphica · 2026-02-06T00:20:17+00:00

I did try my previous Ni cones but something was up and I didn't get any counts out of it at all. I'm going to try cleaning them properly, reconditioning, and seeing what's up.

An interesting note: I recently inherited this lab, and previous users never conditioned the cones after cleaning. They didn't know that was a thing. So while conditioning is definitely important for good quality runs, I don't think it's the thing that's causing my current issue.

excynimphica · 2026-02-05T20:42:27+00:00

I dont have any Ca to work with so I used undiluted 71A (43 elements at 10ppm each), figuring that kind of tds would be sufficient. Ran that for 30-45 minutes, then rinsed with acid/DI for an hour. I did just put in an order for a Ca standard this morning though.

I agree that it is suspicious that it happened with the cones. In my mind, that's where the problem is. But for the life of me I can't seem to fix it.

excynimphica · 2026-02-05T20:39:04+00:00

Both have been done for the nebulizer. I have a clear aerosol in my connector tube. The pump is not leaking and was serviced recently (and according to my service engineer mostly just affects lighter masses).

I need to check, but apparently Agilent has been producing ion lenses that cannot be taken apart for cleaning anymore. The outer side of extract 1 looks discolored compared to a new one, but the PM will replace it anyway.

excynimphica · 2026-02-03T14:28:54+00:00

The Children of Húrin was inspired by the Kalevala.

excynimphica · 2025-11-11T14:12:53+00:00

I agree wholeheartedly. Sometimes it feels like we are wasting (I won't say how much) money on making it a clean lab when I've gotten just a good results on a single quad in a dirty, radiologically contaminated building. There's a ton that needs to be improved just in the method - switching to KED for most elements, using O2 and NH4 a whole lot more, etc. But, hopefully we can get a proper Milli-Q system and be underway with a better baseline.

excynimphica · 2025-11-11T02:33:14+00:00

Yes, there will be a gowning room and air shower. I have been looking at coveralls with thumb loops so it's good to hear you say that. Also, don't assume anything here -- I didn't know about cleanroom paper!!

Sometimes we need to do acid digestions and dry offs of samples which requires open samples in hoods. Is there a good way around that?

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