Varnished items from older collections.
 

Hi,
I think some of us if not most of us have come across items from older collections that have had the metal parts of an object varnished in order to protect the piece from rust. I would value the opinions of the members with regard to removal or not of this type of old protective varnish. If removal was proposed then how would you proceed and with what method? I look forward to your opinions and suggestions.
Regards,
Norman.

Hi Norman,

yes, i have some blades which were covered with shellac. Shellac becomes discolored and ugly after some decades.

I use Nitro thinner or Aceton to remove the shellac. After that treatment the blade must be oiled thoroughly.

If i have wood with shellac I use very fine sandpaper (from 1000 or 2000 to 7000 grain) and a metallpolish called "Gundelputz" for the finish (thank you very very much for that tip Alan Maisey!).


Roland

Shellac can be removed by benzine, chemical clean.

Yes you are right, that acetone is quite good.
When it comes to blades it is relatively easy, but when it comes to chiselled hilts, it is not always that easy to remove the lack in all corners - so be very careful when you do it - to get out in all the corners.

and now the mandatory OSHA warning:

remember to use volatile solvents outdoors or in very good ventilated rooms. most are poisonous and some are carcinogenic. i don't want to lose any of us. solvent resistant gloves and goggles/face mask are a good idea. nice strong outdoor lighting from that big white ball in the sky will also assist in improving your removals from corners and areas that may hide in artificial lighting.

acetone has a much lower toxicity that benzine which can cause permanent damage if inhaled, ingested or absorbed thru skin contact. both are highly flammable, so no smoking, or sources of ignition nearby. benzine is the major constituent of gasoline/petrol.

sadly, we rarely see that thing in the sky that gives off all the light here in the UK. i think it's astronomical name is Sol, or something similar. (it is raining here as usual) i have a dim memory of something we called the sun, way back when i was a younger in alabama, usa. might be the same thing.

Wait a minute; have you forgotten the Douro and the Portuguese Sol ? ;)

Hello All,

I would also vote for acetone, having used it with success on several occasions.

Sadly the varnish I normally encounter has usually turned a nasty treacle brown colour, from a mixture of dirt, cigarette and other smoke.

My first encounter with it was on a beautiful horn handled lambendh kukri, which had come from a large display of ethnographic weapons from a country house.

If you need to remove varnish from horn, acetone works well, but remember to treat the horn with mineral oil afterwards, as it soon sucks the moisture right out which can shrink the horn and make it brittle.

Good luck!

Chris

no, i remember sweating like a flea in granny's fryin' skillet on the costa, not quite so hot in the mountains...even a few shady bits. ;) the cure of course is vinho verde in copious quantities. coriander (cilantro), garlic and egg soup over bread also helps. oh, and a nice large port after dinner takes away the last pains and mellows out the world.

Varnish and shellac removal depends on what the lac was mixed with to make the finished product.

In old "classic" finishes methylated spirits will mostly remove the stuff. Metho & 0000 steel wool, then a hand rub with baby oil.

Newer finishes might need acetone, but the old stuff just wipes off with metho.

What would you recommend for this yatagan which is coated with some type of clear lacquer. The hilt seems to be niello.

estcrh:

This might be a silicone wax product. "Antiquewax," a polish for antique furniture, has been used by some people to produce a shine on the metal and slow down oxidation, and it works fairly well. There are similar products sold specifically for blades. Some folks have even used silicone car polish but that is too shiny and thick for my liking.

Once on, it is not easy to remove the silicone finish. I have found an industrial solvent, methyl ethyl ketone (MEK), is fairly good. I apply it with a rag several times and wipe off the residue. The fumes are quite intoxicating and make one feel dizzy, so be sure that you do any stripping in a well ventilated area and away from heating sources.

I treat all of these solvents as highly toxic and potentially flammable/explosive. Impermeable gloves and eye protection are a must and avoid exposures via breathing or skin contact as much as possible--I do no more than 5-10 minutes stripping at a time and take a complete break for 30 minutes or so without breathing the fumes. Dispose of the cleaning rags carefully (not in the general trash)--I burn mine in a wood stove rather than throw them away.

Good luck!

Ian.

P.S. Use an organic solvent only on metal surfaces. Not on wood or other organic materials. Solvents can seriously damage these materials.

Thanks Ian, I will try this on a small area first.

Roland, Post #2

With apologies, I don't think I can take credit for that advice Roland.

Hi,
Many thanks to all those who took the time to answer. I take it from your replies that nobody would advocate leaving the varnish as is and that removal is the best option.
Regards,
Norman.

Norman,

Personally and professionally, I'd say that if you're careful then removing the varnish is generally preferable. Primarily this is for four reasons:

1) The lacquer's composition is unknown, and undesirable impurities may have been added to it during mixture (i.e. the purity of the original solvent is unknown, in addition to potentially damaging impurities entering the compound from the crushing and liquefying stages).

2) The lacquer's integrity is unknown; an uneven coat may have worn away in certain spots while remaining thick in others, or may never have been properly applied at all. Liquid coatings such as shellac (and also nitrocellulose lacquers such as Frigilene) are always problematic in this regard since they tend to run, and I tend to think that a coating that gives a false sense of security is as bad as no coating at all.

3) The lacquer is likely not to be up to scratch vis-a-vis long-term conservation properties. Shellac undergoes hydrolysis into acids (aliphatic and alicyclic acids, no less - from what little chem I understand, the more unstable sorts of organic compounds), which are in turn likely to cause damage to the object if they aren't neutralised. Frigilene and other nitrocellulose lacquers, in accelerated aging tests, have tended to peel off, discolour, and become difficult to remove. I myself have observed the characteristic yellowing of frigilene lacquer on a sword in the RDG collection, the lacquer having been in place approximately 20 years by that time. There's a rather good publication from the Getty Conservation Institute for anyone interested.

4) Frankly, that's a bloody ugly finish!

Let us know how you get on; there are a few objects in our collections that have been lacquered in their long (and long-suffering) lives, and I'd be interested to see the results of your work when planning any on these objects.

- Meredydd

Be very careful with the niello - a type of oxidation easy to take off and not to place back on. In fact, I'm not sure if anyone does niello anymore since the chemical fumes are very toxic.

Niello is a horrible mix of lead, and a little copper. When it's thoroughly mixed and still completely molten, a handful of powdered sulfur is mixed in, stirred, and poured into long thin (1/4") strips and allowed to cool.

Once a decorative design is chiseled into a piece of metal, the metal is heated and the niello strip is "mushed" into the design leaving excess. Or, it can be ground into a fine powder and applied like vitreous enamel and then fired. Allow to cool, and file the excess away, using a coarse single cut file. It's like filing graphite, soft, with a tendency to chip if you rush it. Polish any file marks polish with emery.

I did some of this while a student forty years ago, under a laboratory vent hood, and, believe me, it's a smoky, sulphurous, stinking mess. Glad I did it once or twice, but I don't think I ever want to do it again.

There are many formulae recorded, each with slightly different compositions and working attributes coming from early sources from around the world, but, I post this here for reference and not as a recipe, so unless you have laboratory ventilation, don't do it.

If repairs are absolutely necessary I would look into using an epoxy based mixture instead.

Hi,
Many thanks to all for your continued interest. I have taken on board your advice and suggestions and will proceed accordingly. The items in question are Zulu type spears, 1x Iklwa and another as yet undefined, which would appear to have been collected in the latter part of the 19thC or very early 20thC. I will post said items shortly.
Thanks once again to all who participated in the thread and gave of their experience and knowledge.
Regards,
Norman.

These three pieces were covered in thick yellowed old varnish. I took it off with Nitomors varnish remover from B&Q. Then ran the pieces through my hand smothered in olive oil, only the very best cold pressed virgin. If the wood has any patina It is brought back. If the item had no patina at the time of collection and varnishing it will be as it was, old with no patina.

I wonder if you could get it to boil, flake, and become peel-able with something like hot air from a hair dryer.