What to preserve during equipment refurb and how?

[TorontoBuilder]

I am looking at stripping the entire finish from my lathe, and while I wont be restoring the lathe to original factory paint options I think it is appropriate to preserve some original details such as stamped markings, and inset serial numbers on each component as as those shown below:

The questions are:

Is the stamping deep enough that it penetrates below the original paint sufficiently to be retained if the paint is removed? Especially the clc27 circle...

I don't think that what appears to me to be an anodized aluminum with the serial number can be removed without damaging it. Normally I'd clean this with a solvent, carefully scrape the loose paint away around the disc with my sharpest chisel and then sand as close as possible with sanding sticks.

If I go with sand blasting I can clean the serial number disc with solvent then hand scrape away as much loose paint as possible, then mask it with duct tape and be done with it.

I'm currently souring laser ablation specialists with an eye to stripping the lathe, and as far as I know the laser will vapourize down to the bare metal, but what does that mean for an anodized surface on aluminum?

I suspect I'll lose all the stamped details, and whatever crud and or pigment is filling the text on the serial number disc and unless the operator is highly skilled and adjusts the laser to the very lowest setting for the disc area I'll lose the anodizing.

The good thing is that the laser has a very controlled and sharply defined area so that areas to be preserved may be avoided entirely and left to hand preparation.

So I'm debating the following...

First treat the area with solvent cleaning and a tooth brush. Then make a rust stripper gel and apply to the area and gently rub with a tooth brush to remove as much rust as possible around the hole in particular. Then rub/strike with a sharp edged hardwood scraper to knock off any loose paint and the same techniques with a pointed stick around the disc to remove loose paint.

Then a very light sanding with a fine emery paper to knock the surface of the paint down just a touch and remove some more grime. Wipe with solvent and then cover with painters tape. and Instruct the laser technician not to treat the masked areas.


Finally prior to applying the final clear coat remove the masking tape, rub a bit of the chosen green paint into the stamped figures wiping away the excess with lint free cloth with a little acetone on it and allowing to cure.

Finally apply clear coat to the lathe. The affected area will be left like a little a rat rod spot.

Or just laser it all away and say who cares? I wont while I'm using it, and I don't care who gets it after I die. I already violated the original design by altering the variator housing.

 

[Dabbler]

Back to the 20,000 foot level, it depends on if you are attempting to do a museum level restoration, or 'do your best' to preserve the marks?

I definitely go down these rabbit holes all the time, to my detriment.

A 'good enough' approach may be to fill the letters with a paint resist, clean off excess, then paint and pick out the resist with a dental pick.

I'm sure there are a dozen ways to do this, but the easiest is to paint it and pick out the paint to show the marks.

 

[Susquatch]

I like @Dabbler 's approach if you have to do it. But I myself wouldn't bother doing anything cosmetic at all.

A woman who ages naturally and loves herself for who she is, is twice as beautiful to me as the unhappy one redone with plastic surgery trying to be who she isn't.

That is just a round about way of saying that I'd leave it as is and love it with all its battle scars and natural patina intact. The work it does will not know the difference. If it really bothers you, then turn off the lights.....

Sorry, I know that's not your way, but I couldn't resist adding my contrarian 2 cents.

 

[phaxtris]

I think equipment looks pretty good once it's cleaned/degreased leaving all of the scratches and paint blemishes alone

To me it's the grease and grime that are bothersome rather than the chips of paint missing

 

[whydontu]

Laser will destroy the anodizing. Quick-n-dirty: cut an aluminum disc to cover the existing disc, stick it over the existing disc using Bluetack or hot wax.

 

[TorontoBuilder]

I like @Dabbler 's approach if you have to do it. But I myself wouldn't bother doing anything cosmetic at all.

A woman who ages naturally and loves herself for who she is, is twice as beautiful to me as the unhappy one redone with plastic surgery trying to be who she isn't.

That is just a round about way of saying that I'd leave it as is and love it with all its battle scars and natural patina intact. The work it does will not know the difference. If it really bothers you, then turn off the lights.....

Sorry, I know that's not your way, but I couldn't resist adding my contrarian 2 cents.

I appreciate the contrarian views.

I think painting is necessary because of the projected shop conditions that lend themselves to rust creation. Rather then oil down the entire lathe between uses I'd like to have paint protect 90% of the surfaces and only need to apply oil to bare metal.

I think equipment looks pretty good once it's cleaned/degreased leaving all of the scratches and paint blemishes alone

To me it's the grease and grime that are bothersome rather than the chips of paint missing

Yes, I have thought of the rat rod approach and have given the lathe a high pressure wash of all the painted surfaces and I intend to break it down and put everything in a parts washer. The bare metal ways, cross slide and compound I'd like to remove all traces of rust from, but if I got everything else cleaned up to the point the paint is not flaking and wont flake further then I may just clearcoat it instead.

I have about a month to decide since we need to build a 15M square body shop to do paint work in

 

[TorontoBuilder]

Laser will destroy the anodizing. Quick-n-dirty: cut an aluminum disc to cover the existing disc, stick it over the existing disc using Bluetack or hot wax.

Thank you for the great solution, I knew there were people here that could out think me and find great solutions.

 

[TorontoBuilder]

Back to the 20,000 foot level, it depends on if you are attempting to do a museum level restoration, or 'do your best' to preserve the marks?

I definitely go down these rabbit holes all the time, to my detriment.

A 'good enough' approach may be to fill the letters with a paint resist, clean off excess, then paint and pick out the resist with a dental pick.

I'm sure there are a dozen ways to do this, but the easiest is to paint it and pick out the paint to show the marks.

I'll try this... I can also use a metal plate stuck over this feature to protect if I use laser ablation on the rest of the machine.

edited to change feather to feature

 

[Susquatch]

I think painting is necessary because of the projected shop conditions that lend themselves to rust creation. Rather then oil down the entire lathe between uses I'd like to have paint protect 90% of the surfaces and only need to apply oil to bare metal.

I take it that dehumidifying isn't an option for you.

I dehumidify my whole barn to 50% and it seems to clobber the bulk of the rust issue. I also use a little spray oil and zerust blocks in drawers as my instincts suggest might be needed. Going well after 15 years in the worst part of Ontario.

Even if you paint you need corrosion control.

 

[Stuart Samuel]

I talked to a laser rep (cleaning as well as welding) at Fabtech last month, and he insisted that, at least with their product, you could dial in the effect it had. I showed him some photos of outdoor lights from the Centre Block of Parliament that I'm dealing with, where there are steel, brass, and aluminum parts connected mechanically (welded forged collars, rivets, etc.) that aren't practical to take apart. He also claimed it could be dialed in to burn off old lacquer from a brass chandelier without affecting the patina underneath. If he wasn't full of... uh, then it's possible you could get the paint off without damaging the anodized part.

On the overall cleaning idea... I'd be extremely cautious about buying a freshly painted machine, but I like to at least be able to find the oiling points on the thing. My lathe is grotty enough (hardened oil mixed with chips) that I'm struggling to locate screw heads to get things apart, especially on the underside of the apron, etc. To me, that's too dirty. I'd also like to be able to do average tasks without coming away filthy.

 

[TorontoBuilder]

I take it that dehumidifying isn't an option for you.

I dehumidify my whole barn to 50% and it seems to clobber the bulk of the rust issue. I also use a little spray oil and zerust blocks in drawers as my instincts suggest might be needed. Going well after 15 years in the worst part of Ontario.

Even if you paint you need corrosion control.

Our shared garage shop only really suffers in the spring and fall, outdoor humidity of 80% or more especially after cold nights when the metal hits the dew point unless we heat the garage, which we do ever so slightly. I expect may garage to be worse since the exterior walls are not insulated. I don't want to heat it but I may dehumidify in spring and fall

 

[Susquatch]

Our shared garage shop only really suffers in the spring and fall, outdoor humidity of 80% or more especially after cold nights when the metal hits the dew point unless we heat the garage, which we do ever so slightly. I expect may garage to be worse since the exterior walls are not insulated. I don't want to heat it but I may dehumidify in spring and fall

Ya, I heat in the winter so no need for the Dehumidifier then.

I only use it spring summer and fall. A medium size unit and an area fan is more than enough to keep my 40x80x20h barn below 50%.

I'm not sure why you don't have a summer problem too.

 

[TorontoBuilder]

Ya, I heat in the winter so no need for the Dehumidifier then.

I only use it spring summer and fall. A medium size unit and an area fan is more than enough to keep my 40x80x20h barn below 50%.

I'm not sure why you don't have a summer problem too.

It's all in the dew point, the fact we have an attached garage and keep the door closed almost all the time so space is semi-conditioned with lower RH and temp than outside air.

Even if outside humidity leaks into the space and raises the relative humidity to 85% the air temperature remains steady around 72F. In those conditions the dew point will be 67.2 degrees. All our massive machines remain stable at 72F and never get close to dipping below the dew point until the RH rises to over 98% relative humidity.

We do open the the garage door on occasion, but only on days where the outside air conditions will not raise the dew point above 70F.. so 84F and lower than 60% RH...

 

[Susquatch]

It's all in the dew point

I get that. I've written extensively about it. But ya, not everyone does. And lots don't understand it.

What I didn't know is that you had some air exchange with the house which provides enough dehumidified air in the summer to keep you below the dewpoint.

As you know, my barn is a stand alone building so summer is as bad (and sometimes worse) than spring or fall. That's why I asked.

Do you monitor humidity in the garage?

 

[TorontoBuilder]

I get that. I've written extensively about it. But ya, not everyone does. And lots don't understand it.

What I didn't know is that you had some air exchange with the house which provides enough dehumidified air in the summer to keep you below the dewpoint.

As you know, my barn is a stand alone building so summer is as bad (and sometimes worse) than spring or fall. That's why I asked.

Do you monitor humidity in the garage?

yes we monitor the humidity in the garage and we prop the door to the house open when working in there to get that extra little bit of cool when we need.

 

[ChazzC]

Mr Crispin did a 2-part video on Reviving a Lathe which may help guide you in the extent of restoration: