Hello everyone.  I recently inherited a bunch of neat old furniture from the late 1800's and early 1900's.  It's all finished in shellac.  Somewhere in the last 100 or so years, someone took it upon themselves to patch scratches and dings with urethane.  One such item is a beautiful old mahogany wardrobe  with careless brown splotches of urethane on the doors.  

 

How can I remove the urethane without removing the underlying shellac or patina?

 

Thanks,

Tom B.

get this man's attention... @kmealy....

What Stick said.

I wish you luck, Keith may have something, but I'll bet it will be iffy. If you find who did it have them arrested for crimes against furniture.

Not that hard, except for the "keep the shellac" part.  There are now water-based odorless* strippers that will remove the finish, but not sure why it's important to keep the shellac when you can simply recoat after stripping.  From your description, the overcoats were attempts to fix breaks in the old shellac?

 

 

*So I hear.  My smellum stopped working a couple years back, so the entire world is odorless.  

Hi Pete - yes, the urethane was actually a repair attempt but a bunch of lazy hoarders. I am trying to keep the shellac intact in order to make color matching easier.  It also give me more confidence that I have not removed the warm color of the wood by going through both the urethane and shellac layers.

 

Tom

10 hours ago, Stick486 said:

get this man's attention... @kmealy....

Huuuh?  Wha? I'm awake (I think)?

 

I'm afraid I cannot think of a good solution.   Anything that removes the urethane will remove the shellac.  You might be able to scrape off the urethane with a fine cabinet scraper, but I'll bet it would be tough since the shellac was probably thin in those spots anyway.  Urethane is tough to strip; shellac is easy.  In other words, urethane has good resistance to solvents while shellac does not.

 

I just "cleaned" a small spice box with an old shellac finish.   I tried to just freshen it up (saving the finish), but customer wanted it "cleaner"   I ended up rubbing with denatured alcohol that lightly stripped the old finish and tons of dirt.   Then applied some fresh finish and toner.  This would be similar to what ATM strippers such as Formsby's would do -- apply with a Scotch-Brite pad and will remove most of the finish and leave a little of the color.   Will have to get an "after" picture

Get some good single edge razor blades and a box cutter as shown in the picture.  The razor blades can be inserted as a scraper blade as shown on the bottom one.  Carefully start at the edge of the poly and try scraping it off.  The tool that did that probably didn't take the time to sand or clean it and the poly may lift off.  It has worked to lift paint in a few instances for me.

 

4 hours ago, kmealy said:

Huuuh?  Wha? I'm awake (I think)?

 

you need me to send the dogs in there...

9 hours ago, Stick486 said:

 

you need me to send the dogs in there...

The smell of fresh cake donuts will wake me up.

10 hours ago, HandyDan said:

Get some good single edge razor blades and a box cutter as shown in the picture.  The razor blades can be inserted as a scraper blade as shown on the bottom one.  Carefully start at the edge of the poly and try scraping it off.  The tool that did that probably didn't take the time to sand or clean it and the poly may lift off.  It has worked to lift paint in a few instances for me.

 

Yep, that would be a "fine cabinet scraper"   Maybe the shellac was waxed and the poly did not adhere all that well.