Hi gerry,

Do you have a fixed steady you could use to support the work without the tailstock?

Congratulations on having a high precision comparator! Well worth taking care of it.

Maybe the way is the hard, manual, way with a hand held wire brush?

The thread is there to adjust the head up and down the column,ratheyr than to provide a great axial thrust.

So wire brush with regular visual inspection.

Other than that, rwsort to chemical means of rust removal

Howard

Fixed steadies are awesomely useful once you've made one, especially for big long pain in the neck jobs

Also allows you to use 100% of your lathe bed

Clean the first couplr of turns manually. Bore out a block (tufnol, alloy, wood) to the OD of the post. drill two holw onf pitch apart 90 deg to the bore. fit a pin with diameter = groove width in one and a clean-up cutter in the other. run it up the thread with the guide pin behind the cutter.

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In a similar situation I found the rotary wire brushes made for Dremel's, Multi-Tools et al were narrow enough to get down into the grooves. Life time was distressingly short and care was needed to start teh whole brush into teh groove without poking strands outside. I found putting the brush in stationary and winding up from minimum speed worked best but my slots were pretty much exactly brush width.

Results were good.

Clive

Hi Gerry and all,

Bill has beaten me to it (and stuck his head above the parapet first) – I would support cleaning it of all grease, wire brushing by hand to remove excess rust, then immersing it in Evaporust in a tube. Wire brushing to remove excess rust reduces the amount of Evaporust needed to clean away the residual rust or the degree to which the Evaporust is "used-up" on a given component.

Alternatively (and this is what I do when the component is too awkward in shape to immerse properly, or if I haven't enough Evaporust in stock to do full immersion), I "bandage" the component in paper towels well-soaked in Evaporust,.then cover it in a plastic bag or cling-film to stop it drying out. That way may need multiple applications (and where feasible I often use wire between applications), but it's probably more effective than just brushing on (others may have different experiences). Be careful not to let the towels or component dry out though, as (in my limited experience) you can end up with a hard-to-remove black deposit when it's been allowed to dry out.

If the rust is very light, you may not see any significant traces of it after treatment. If it's more heavy, the formerly rusty patches will probably be darker and I don't think there's much you can do about that without removing metal.

As I have bought quite a few of my tools and machine accessories at knock-down prices simply because they were covered in rust and looked absolutely horrible, yet cleaned up well with Evaporust, I've had positive experiences of this overall approach! I'd certainly suggest trying it over and above a highly abrasive approach that might cause unnecessary wear. Obviously if the screw surface is really pitted with rust and likely to act as a "file" on any nut etc. that engages with it, then all bets are off and a more aggressive approach may be needed to get rid of the pits.

That's my suggestion anyway! Other experiences are welcome. Usual disclaimer, I have no connection with Evaporust other than finding it useful.

Kind regards

Arthur

Pete,

as per Gerry’s opening remarks

”the main support post”

MichaelG.

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Edit: __ I obviously don’t know which model he has, but the general principle is presumably like this one:

https://www.ebay.co.uk/itm/256201549864

Edited By Michael Gilligan on 27/09/2023 06:53:06

You can get "Evaporust" in gel form: I have seen it used on Hand Tool Rescue on Youtube.

Alternatively, the oxide removal solution supplied by the Allendale Group, for their ultrasonic cleaners seems to do a very similar job to Evaporust. I have used this solution by itself – to remove rust without the ultrasonic cleaner – and it is almost magical how you can place a rusted piece of metal in the solution, and a day later, it comes out completely rust free, and smooth, and in some cases as good as new.

Much easier than laborious scraping, grinding, or brushing off the rust – wire brushing can simply polish rust rather than remove it, and you are going to have a very difficult job to get rust out of that thread manually without damaging the thread walls or profile, and introducing lots of random irregularities.

Chemicals are the answer in this instance, I reckon.

With the Evaporust and maybe wire brush treatment, at that point I'd probably use what I have for years Gerry. Made in Germany with the brand name of Simichrome. And probably not too hard to find if your in the UK. With a quick check it looks like Your Amazon UK has it. It's not exactly cheap, but a little goes a long way. Those Sigma gauge stands look to be high quality, the shaft OD and groove should polish up as good or better than factory new. And that polish is pretty gentle so it wouldn't be removing a measurable amount of metal. So far I haven't found anything better than that Simichrome with any metal type unless you go to a whole lot more effort with the felt buffs and industrial polishing compounds that would definitely remove more than you want to. The OD would be most easily done with the shaft in your lathe and that polishing compound on a cloth rag. The groove will be a bit more tedious, but a Dremel or similar rotary tool and the small felt buffs they sell for them, plus that polish is what I think I'd use.

How about trying these mops being loose leaf will enable it to clean in the thread. Pick a fine one so not to round over the edges too much

Nice result, Gerry

MichaelG.