AlHg and SS stirshaft

[RoundBottom]

would the HgCl2 in a MeAm AlHg attack a 304 or 314 stainless steel stir shaft?

[cublium]

No,probably,and if it does,damage will be very little(like becomes dull-coloured or something).The solution is basic and only zinc and al form hydroxonium complexes with strong bases like NaOH or KOH.Methylamine shouldn't react with this metal nor activated aluminium.Hg salts may react though(cub once heated Hg chloride on SS pan and at some point it(twas over 100C for sure) bursted on fire and pan was covered with some shiny coating,SS got amalgamated cub thinks.).Guess you just have to try.Titanium doesn't react with Al/Hg mix that's for sure and teflon seems to handle it just fine too(personal experience).

[abolt]

According to material charts I have read Hg and salts will affect S/S.

Why not get your stirrer rods teflon coated?

[RoundBottom]

SWIM figured that SS and HgCl2 wasn't a good idea.

SWIM has a glass stirrer and some paddles, but SWIM needs to shave the paddle down to fit in a 24/40 neck.  the SS shaft has a different mount, so that paddle won't work.

SWIM has looked high and low, and can't find anyone who does teflon coating.  SWIM was looking to coat the inside of a large pressure vessel.  coating the SS stirshaft will make it thicker, which will lead to problems with the teflon stirrer bearing, but that can be addressed easily.

[abolt]

SWIM has looked high and low, and can't find anyone who does teflon coating.  SWIM was looking to coat the inside of a large pressure vessel.

They are around......look harder.

coating the SS stirshaft will make it thicker, which will lead to problems with the teflon stirrer bearing, but that can be addressed easily.

You only require a thin coating and the O ring that seals your stirrer bearing will have some give in it. Also, just get the lower half of your stir rod coated.

[Chromic]

You could use multiple layers of stretched teflon tape, then heat it up to about 250C to fuse them together... it's not a perfect seal, but it's pretty close.

[Propoxyfiend]

I've never successfully manufactured any substance of any kind.  However, when swim attempted their first batch of nitro toluene(oh my was that a bummer).  In a jam without access to the store bought stirbar:  Magnets(USD $5.95) were purchased at a school house supply store. Teflon tape(USD $1.50 per roll - I think) in the plumbing section of the local hardware store.  The tape was wrapped around the magnets in an oval shape.  A bic lighter(USD $.99) was used to attempt to fuse the layers.  This was successful & the little guy whirled and bubbled creating a wonderful vortex in the nitric acid and toluene mixture.  However, every now and again the tip of the tape kept insisting on comming off.  Until someone invents self fusing teflon tape. . .  Possibly rolling it around on top of a hotplate using a "pokie-jabbie"(C)(paperclip used to clean bowl) would have proved more effective in total fusion!  BTW the same school house supply store sold me the iron fillings too!  Common sense, yes?  However, I think Labtop mentioned it moons ago.  Thanks. . . .
PS: Ya, what Chromic said!

[scram]

I asked this question a few years ago and attempted it w/ss. I believe it still worked successfully and I remember the shaft being dulled. I was eventually able to find a PP blade through a well know supplier. I ordered 2 or 3 types and only 2 of them fit into a "tooled" neck flask. One of which needed a little sanding on the blades. In all blades they were the "open-fly" type which means the only opened up when the stirring commenced. I can't say for 24/40 if these would fit.

[RoundBottom]

only the shaft is SS.  the blade is teflon.  SWIM has a glass shaft, so SWIM will use that.  this is at the 1600mmol level with about 120g of foil.

fwiw, to make a stirring paddle (not shaft) you can buy teflon in sheets of varying sizes at most plastics stores.  look for 3mm or 1/8" thick.  make a template of cardboard (ensure that is fits in the flask neck), and cut it out with an x-acto knife.  smooth the edges with some sandpaper, and put a hole in the middle to attach to your shaft.