OldTools Archive

Recent Bios FAQ

265406 John Ruth <johnrruth@h...> 2018‑03‑13 "Patina" vs. "Crud"
Gentle Galoots:


I'd like to hear some points of view on when is it appropriate to clean off
"crud" vs. "over-cleaning", which removes the "patina"


Case in point is a wooden machinist chest which is going to need some TLC
because somebody pried open every one of the individual drawer locks.  There are crude steel plates covering the key holes. In
other words, it's already wrecked to the point where it will never be a display
piece, but rather a user.


It's got a grimy mess on the outside - one's fingers get blackened from handling
it.  When I brushed it off, the bristles of the brush got dirty. This did remove
a lot of grinding wheel dust and fine metal shavings, though.


My intent is to first give it a wipe-down with mineral spirits on paper wiping
towels.  I can't imagine that the oily mess has NOT stained the wood.


After a couple of wipe-downs, I expect the wood will still be deeply oil-
stained.   I think that's as far as I will take it.


The next step might be a trip to the furniture refinisher's lye tank, to
saponify any remaining surface oil, but I think I'm not going that far.



I don't think I'm hurting anything when generally brush off any loose crud on an
old tool.  Cleaning with mineral spirits, trying it on an inconspicuous part
first, doesn't strike me as vandalism either.


John Ruth

In snowy Metuchen, NJ.
265409 Erik Levin 2018‑03‑13 Re: "Patina" vs. "Crud"
John Ruth wrote: 


> I'd like to hear some points of view on when is it appropriate to clean off
> "crud" vs. "over-cleaning", which removes the "patina"
and:

> In other words, it's already wrecked to the point where it will never be a
> display piece, but rather a user.

I think you answered your own question, here. Make it the user you want it to
be. If it was historic in nature, that is a different issue, but a machinist
chest (presuming it isn't a special, hand mode prototype Gerstner or one
fashioned by Maudslay during his apprenticeship), especially if physically
damaged and already modified, is not worth the trouble to restore, IMHO.


> The next step might be a trip to the furniture refinisher's lye tank, to
> saponify any remaining surface oil, but I think I'm not going that far.

I'm glad to hear that you are not truly insane. Unless, of course, it is
Maudslay's tool case...

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265410 Kirk Eppler <eppler.kirk@g...> 2018‑03‑13 Re: Fwd: "Patina" vs. "Crud"
On Tue, Mar 13, 2018 at 9:28 AM, Dwight Beebe  wrote:

> I know how everyone loves the BORG, but this might be worth trying.  I've
> used it on older, grimy wooden planes.  Removes the filth, but doesn't seem
> to remove the authentic patina.  YMMV.
>
> https://www.homedepot.com/p/Krud-Kutter-32-oz-Original-
> Concentrate-Cleaner-Degreaser-KK326/203396788
>
>
>
> On Tue, Mar 13, 2018 at 11:37 AM, John Ruth  wrote:
>
> > I'd like to hear some points of view on when is it appropriate to clean
> > off "crud" vs. "over-cleaning", which removes the "patina"
>

All

I have used Krud Kutter, here are some before and after pix.  The chest I
was using it on was trashed in so many ways, that I wasn't worried about
preserving, but making it functional.

Before with a nasty spill on the lid

https://kirkhmb.smugmug.com/Woodworking/Tool-Chest-Two-Drawer/i-f5jZjRJ

During, Krud Kutter in view in the background
https://kirkhmb.smugmug.com/Woodworking/Tool-Chest-Two-Drawer/i-j7HqzKs

Before of Drawer bottom
https://kirkhmb.smugmug.com/Woodworking/Tool-Chest-Two-Drawer/i-xJtSdLw

After (poke around)
https://kirkhmb.smugmug.com/Woodworking/Tool-Chest-Two-Drawer/i-JmsFjG9


Here are some pix from another chest I degrunged with paint thinner (Feel
free to flip forward and back to see the amounts of grunge.)
https://kirkhmb.smugmug.com/Woodworking/Tools/Tool-Chest-3-Till/i-ZsD33hT


To John's original question:  I feel that mineral spirits will only take
off crud, not patina.  Alcohol may take off finish, as Krud Kutter seemed
to, so those would be my next escalation.   I use mineral spirits or paint
thinner on almost anything I am certain is not historically significant,
using you guys as a barometer.



-- 
Kirk Eppler in Half Moon Bay, where much needed rain was slowing the
commute.  And apparently the USPS, as a box made it to middle of Ohio
faster than to SoCal.
265412 Ed Minch <ruby1638@a...> 2018‑03‑13 Re: "Patina" vs. "Crud"
John

hide glue may not survive the dunk

Ed Minch
265415 Thomas Conroy 2018‑03‑13 Re: "Patina" vs. "Crud"
Erik Levin wrote: "...a machinist chest (presuming it isn't... one fashioned by
Maudslay during his apprenticeship), is not worth the trouble to restore, IMHO."
Layers of oily filth coming off on the hands wouldn't be a problem with
Maudslay's chest. If ever a man was obsessive-compulsive....
The conservation orthodoxy is that you start with the gentlest method of
cleaning and get what you can with that before going on to the next roughest.
You can't leave actual dirt in place, not if it endangers the object itself or
could be transferred by someone's hands to another object. Unless, of course,
its something like the Donner Party diaries and papers, which they have in the
Bancroft Library here, from which no-one would dream of cleaning the soot,
grime, water stains, fat, blood... Back to the point, a conservator will use
water (or, actually, damp on a paper towel); then detergent foam; and slowly up
through alcohol to rougher solvents if you actually must. And you re-evaluate
what you are aiming for after each step.
It doesn't always work out that way in practice. I restored a huge late-
Victorian finishing press. 4" square cheeks and 28" long, filthy and with the
wood rough. I went through the water and detergent,and found that no matter how
long I wiped, I still got dirt transferred to the wipe and the wood had a dirty
surface. Went to alcohol, figuring to take off the shellac and the dirt with it.
Things got no better; in fact worse. Then went savage and started using steel
wool instead of paper towels, then started scraping with a wooden scraper. The
alcohol semi-disolved the degraded wood on the surface, and it mixed with dirt
and old finish to form a gloppy viscous mess that looked like diahorrea but
smelled a bit better. Eventually I debrided down to solid wood, planed the
insides of the cheeks where they hold the book, fixed broken parts, and soaked
in linseed oil with mineral spirits. I won't go into the practicalities of
soaking a 4x4x28 balk in BLO. Where I planed the cheeks it was pretty clearly
maple, but the other surfaces were heavily rounded and "organic" in shape, and a
deep brown like old cherry or walnut. The brown color, I could see on the planed
surface, sank in a half an inch, but the wood was solid. It came out beautiful,
but I have never used it. Not once.

I've worked with salvaged chestnut saturated with machine oil (it was part of
the frame of a pen-ruling machine, and had been catching spurts or drips for
decades.)The oil penetrated deeply, and even light scraping left a gummy-feeling
residue on the surface. If I recall correctly I had to plane off about an eighth
of an inch, then had a surface where the oiliness was mild enough that I could
soak the piece in BLO, and the combinationof oils dried sufficiently to make the
wood handleable. Don't count on being able to reduce deep oil stains by rubbing
the surface with solvent, or even with a soak tank. Deep oil may still seep out
over time. BLO is your friend.
Tom Conroy
265416 Claudio DeLorenzi <claudio@d...> 2018‑03‑14 Re: "Patina" vs. "Crud"
Cleaning machinist boxes

I agree with the stepwise approach proposed, but considering all the damage
and filth on some of these, I would go right to a detergent based cleaner
after wiping down with a solvent.  I happen to like old fashioned
turpentine, since you can use it safely on old shellac as well as old BLO
surfaces.  No one mentioned it, so I thought it might be worth
consideration.   I have used crud kutter as well as the Castrol Degreasing
spray which worked better for me.  If a lot of the old finish is damaged
and flaking, I try to figure out what it was, and proceed accordingly.  I
have tried those citrus based cleaners which don’t really work for me,
although they help deodorize.  I hate that old fermented gym sock smell
found on some of these.
  Sometimes the lacquer thinner/acetone/denatured alcohol is your only
solution for the badly damaged finishes.  I like BLO for all workshop stuff
(you can use it over just about any of the old tyme finishes without
issues, and I will then use shellac to seal the insides of drawers,
followed by a wax rub made from beeswax and turpentine.  It gets rid of the
old mouldy smells of barn finds.  I make sure everything has dried out
properly before starting any additional finishes.  Sometimes the moisture
level on these is really high from being stored in damp basements.
I enjoyed the repair photos- thanks for sharing.

Cheers
Claudio
265421 paul womack <pwomack@p...> 2018‑03‑14 Re: "Patina" vs. "Crud"
Thomas Conroy via OldTools wrote:

> Back to the point, a conservator will use water (or, actually, damp on a paper
towel); then detergent foam; and slowly up through alcohol to rougher solvents
if you actually must.

Interesting - a lot of museum conservation is done with manual mechanical
methods (picks, scalpels etc), because they can
be stopped instantly. Any solvent (even water) can be hard to STOP.

I guess books (perhaps fabrics too) require different methods.

  BugBear
265427 Thomas Conroy 2018‑03‑14 Re: "Patina" vs. "Crud"
On Wednesday, March 14, 2018, 2:17:13 AM PDT, paul womack 
wrote:
 
 Thomas Conroy via OldTools wrote:

> Back to the point, a conservator will use water (or, actually, damp on a paper
towel); then detergent foam; and slowly up through alcohol to rougher solvents
if you actually must.

And BugBear replied: "Interesting - a lot of museum conservation is done with
manual mechanical methods (picks, scalpels etc), because they can be stopped
instantly. Any solvent (even water) can be hard to STOP.

"I guess books (perhaps fabrics too) require different methods."

  An excellent point, and one that I overlooked in trying to get to principals.
A dry wipe or hard brushing would be earlier steps. And notice tht the water
steps are done damp, not wet, and the detergent used is just the foam, not a wet
soapy rag. The idea is, as you say, to be able to stop immediately.
The actual procedure with books is quite a bit different, mostly because any
solvent except water is too rough for most books, but also because so few books
will bear the cost of wet treatment. Art-on-paper conservators do a lot more wet
and with solvents, but they have to deal with one piece of paper that may be
worth thousands of dollars rather than hundreds of piece of paper worth a
cumulative couple of hundred if everything is perfect. The cost is borne better
by art on paper. You can take your time, and still get paid for it.

Tom Conroy

Recent Bios FAQ