This is a living document, with one section header corresponding to each date with a notable entry. It acts pretty much like my diary for the lab, and honestly, its more for me than it is for you, but if you find it interesting here it is.

I am starting fresh with this new document today, but I may occasionally back port some old entries from my old local diary to fill in some gaps & interesting anecdotes throughout the future.

2026

02-27 - Friday

Coolant Swaps and Electrical Work

Today is mostly a maintenance day in the lab. I got in early today to let our electricians at Votaw in for the 4th day in a row. Votaw has been re-working our electrical system to offer more surge protection for our sensitive devices at the breaker-level, and adding more outlets and amperage in the lab so I don’t keep taking out the entire circuit with our High Vacuum Evaporator. They have been overall very pleasant to work with, and I would recommend their services.

Time for a coolant swap

I got started today by preparing to do a coolant swap on the SEM. It needs its coolant swapped because that coolant is about to experience its first birthday, which our fancy sticker here very explicitly warns against:

Observe the horribly faded 2-28-25 date on this sticker. Thank you past me for condemning me to always having to do this at the end of a hectic and short month.

Honestly, I’m glad for the sticker, because I forgot I only need to flush ~1.5 gallons, I somehow had it in my head that there were 5 gallons of coolant in here. I already have a 5 gallon jug of pre-diluted OptiShield sitting in the lab right now, so I am all set probably for next year’s swap as well.

Learning from mistakes

Last time I emptied this thing, it was mostly distilled water I was running in the loop, which is a lot less nasty to get on your hands than the OptiShield that is in there now. I spilled so. much. water. on the floor. I spilled so much last time for 2 reasons:

1. Our oil pan was not perfectly flush against the back of the chiller, I cut a hole in it for the chiller drain spout to fit through almost a year ago, but the ridge still caused the pan to sit out from the drain plug a bit.
2. Last time, I had to open this drain valve with a pair of pliers, which slipped a lot, mangled the plastic a bit, and overall was very difficult to quickly open and shut.

I fixed the first issue by trimming the back rim of the oil pan down so that it is now flush with the back of the chiller.

For the valve issue, I quickly whipped up a new design in fusion 360 that acts as a turn handle for that valve.

After 1 quick revision to make the length that grabs the valve stem a bit longer, and the knurls just a touch deeper, this tool is ready to help us open and shut this valve with record ease and speed.

The new handle installed in its temporary location for draining. Also seen here is the expert and perfectly straight cut I made to make said pan sit up against the machine a little better.

Luckily, I had to disconnect and move all our pumps for the electricians to do work in our space earlier this week anyways, which would normally also be part of this process, so perfect timing on that. I took some extra time to re-position some equipment and give myself a comfortable and ideal work area for this coolant swap.

It may not look like much, but its about 100% more standing / kneeling room than usually exists in this corner of the lab. We need all the space we can get to get this thing drained and cleaned out properly so it can take its new coolant.

As always happens when I reach this phase in a project, I realized I don’t have the last thing I need to actually start it, a 5 gallon bucket. So I need to go run to Menards to get one. Its questionable at this point in the day if I will be back in time to do a full coolant swap and re-assembly of the equipment corner this evening, so likely the next update in this doc will be on Monday or if I get some time this weekend, we will see. I am not worried that leaving coolant un-circulating for 2 days past its expiry will damage anything, we just definitely need to get it swapped out before the next time we power it all on.

Code work

On another note, I’ve done a lot of code work today both on this blog and the site at large, cleaning things up and getting Bri set up with an editor so she can start adding some content to this site as well.