Expert: Thomas - 10/23/2005

Question
Hello,
I recently purchased a letter opener that has a sterling silver handle and mother-of-pearl blade.
It must have been repaired at some point because there is glue residue where the handle meets the blade.I removed most of it with "goo-gone" and fine steel wool, but there is a stubborn blob remaining. Can you recommend something (a product or technique) that will remove the glue and not damage the mother-of-pearl? Thank you.

Answer
Hi and thanks for this question.

Janette, you must have nice letter opener!  I would want to clean it up, too and remove unsightly cement. My general recommendation is to soak the glue area with acetone, pretty much the same ingredient as nail polish remover.  Acetone may be purchased in small cans from hardware stores.  The first concern with using solvent to remove the glue is the blade: Is it mother-of-pearl or a plastic stimulant?   Since the mop is the blade part and not simply an inlay in the handle, I suspect the blade is the real stuff and not plastic.  However, if the blade is plastic, a solvent like acetone may easily dissolve and damage the blade.  Acetone will not adversely affect real mother-or-pearl.

Still, to be sure, one little test may be made.  This test is not foolproof but will reveal most plastics.  Be aware the test could make a tiny mark on the blade since heat is required.  Take a needle, preferably a dull one or with a broken point, heat the point in a flame till the metal shows a slight red color. Quickly touch the hot end to a “less noticeable”  part of the blade.  Plastics will generally smoke and melt a tiny bit and even smell like hot plastic.  Mother-of-pearl will not melt or smell like hot plastic.  The test might leave a slight browned spot on the pearl, however.

Acetone is very evaporative. This means it should be sealed off or it will evaporate into the air, with a peculiar smell and some risk of fire if any flames are near by.  The same holds true for some nail polish removers.   If you can fit the entire opener into a jar or zip lock bag with acetone applied to a paper towel wrapped around the glue spots the solvent will stay in the jar or bag and be concentrated on the glue areas.  The fumes in the bag or jar will work on any glue in there and that I why in included info on cementing the blade back to the handle.  Once the glue is dissolved, the blade will likely be loose.

CEMENTING AND FINISHING MOTHER OF PEARL.
Using Epoxy Cement.    If acetone removes the glue ok, the blade will need only to be washed clean.  If the acetone makes the blade loose in the handle, you will need to cement the blade again to (or “into”) the handle.  I suggest a two part epoxy cement of the sort that cures water clear and not an amber color.  A good craft store might be able to recommend a suitable brand of epoxy cement.  One excellent two part epoxy is called Epoxy 330, made by Hughes.  This is often sold by rock shops and some craft stores.  The epoxy cures in about 2 hours and sooner if warmed slightly. The parts must be held in position while the cement cures.  Mix equal parts of the two part cement with a toothpick or similar item.  Slightly warm the silver handle, put a small amount of epoxy where the blade contacts the handle and support in place.  You should work out how to hold the parts together before going for the glue!   By slightly warming the handle(like with a hair dryer or light bulb) the heat makes the cement become much more water-like so it flows easily.  Only a little is needed to flow into the contact areas of the blade and handle.  Leave the toothpick(mixer) on the blob of unused cement and you can use this to judge when the cement is cured without disturbing the letter opener.

Finishing Mother-of-Pearl.   Did you notice the steel wool you used for glue removal left marks on the pearl parts?  A very fine steel wool will leave fine marks but these may be buffed away for a nice shine.  If a satin finish is preferred, a very fine steel wool or similar “synthetic steel wool” pad (as ScotchBrite brand but only the finest grades) may be used to rub the pearly surface.   Even a very fine sanding with sandpaper of about 600 grit to 1000 grit may be used.  Fine sandpapers may be found at auto supply stores since the better qualities and finest grits are used for finishing auto body work and rubbing down finishes.   If you use a sandpaper, it should be a wet/dry type and used with a little water splashed on the pearl to help lubricate the sanding process.  Sand a little, wash off, dry, take a look and continue as needed.

A fine razor blade edge or similar sharp edge may be used to gently scrape the ugly glue away if you do not want to try acetone or another solvent.  First see if an “edge” of the cement will come up so the residue may be pulled away with tweezers, etc.  If not, use the edge of the blade to gently scrape a bit at a time away.   If the cement is a soft kind, not hard like cured epoxy, the normal solvent like acetone will possibly not work and you will have to remove the glue with a blade and scraping and possibly sanding with paper or a type of “steel wool”.   Any scrape marks may be smoothed with the fine sandpaper mentioned in the previous paragraph.

A shine may be restored by rubbing the blade with a stiff to hard felt cloth with a white jewelers rouge on the cloth. A “compound for polishing plastics” will also work pretty well. Do not get the liquid type but the kind which is a solid bar of compound. (The solid plastic polishing compounds actually buff the surface by the rubbing action.  Liquid types often are only “fillers” making scratches less noticeable temporarily.)  Similar polishing compounds are also found at auto supply shops and sometimes at hardware stores.   This will take some rubbing so be ready for that!   With a soft cotton buff on an electric motor or with a handheld Dremel type tool, the work goes very, very quickly. By hand it certainly takes more time.

Use a nice quality jewelry polishing cloth on the handle to clean it up.  One very good one is called “Sunshine Cloth”, sold at some jewelry stores and craft suppliers.  The source of these cloths is RioGrande, a company with which many jewelers and crafts stores do business.    ( www.riogande.com )

That is the answer!  Without having your silver and pearl letter opener in my hands for a good close look, I can only guess at the kind of cement you are trying to remove.  This general information should be helpful to you, nevertheless.   If you need more or have something more to ask,  please do not hesitate to get back to me with a “follow-up” or ask again for a clean page.   

Janette, thanks again for the question.  

Wishing you the best with your clean-up project!  
God Bless and Peace to All.       Thomas.              10/23/2005 2:54 PM