Replies

1. 
   Westchester | Mar 25, 2012 05:47pm | #1

   Dry Time

   5 days should have been enough - although don't know how heavy this center piece was or what kind of stain you used. 

   I think you're on the right track to repair but I would sand first not try to just amalgamate -

   SA

2. 
   SteveSchoene | Mar 26, 2012 12:45am | #2

   Remember this is pre-cat lacquer.  It doesn't work quite like ordinary NC lacquer, because of the formula that need catalization it is a reactive finish and won't just redissolve in lacquer thinner.  You may have to strip and start over. 

3. 
   R Bohn | Mar 26, 2012 11:51am | #3

   I think I can save you some testing time, but as far as saving the finish, well,,,,bad news!!!!!!!!!  Cat-Lacquer was designed for kitchen cabs.It doesn't strip well and is very hard to repair. and will not stick to it's self after it is cured.If you try to rub it out, it will scratch and make a mess. It doesn't react well to oils or other finishes. The best way to remove it is to cut it off.  If you buy new furniture with cat-lacquer on it we call it throw away furniture. It can not be reamalgamated. In short....Cat -Lacquer or Pre-Cat-Lacquer is not the best choise for furniture, and should be a crime on antiques.  Better choise would be shellac or old nitro-lacquer.  Both are repairable.  If you can't repair it,    it will never be a family treasure.     Do Good Work       Randy

4. 
   donkondra1 | Mar 26, 2012 12:22pm | #4

   Can you clarify..

   You didn't mention what brand of lacquer ?

   Did you use a wood stain first and what type/brand ?

   If the centerpiece marred it after five days of drying I would suspect the product.

   How old is the lacquer ?  Pre cat normally has a shelf life of six months.

   Did you stir thoroughly first before mixing/straining into your gun ?  It's not unusal for the solids to settle.

   Is the "mar" more like a scratch/ indent or along the lines of a water mark ?

   Contrary to popular belief and the manufacturers directions I've had no problems sanding and top coating with pre-cat lacquer after a week and even after a number of years.

   If necessary I've prepped with a light sanding with 320 but usually just a good wipe with a 220 foam sanding pad.

   The product I used for years was Sherwin Williams pre cat.

   Cheers, Don

5. 
   hammer1 | Mar 27, 2012 11:41am | #5

   You probably put way too much lacquer on the top. Spot fixing isn't a good way to go. If possible, I would sand out the problem and recoat the whole top. If that doesn't work, you may need to strip it and start over.

6. 
   MichaelTheFinisher | Apr 01, 2012 08:40am | #6

   Thats not going to work

   d_l_white wrote:

   I recently finished a table with pre-cat NC lacquer. It turned out beautiful until we placed a centerpiece on it and overnight noticed that it had marred the lacquer. (I should have known better that 5 days of drying was not enough)

   Do I need to take it apart, haul it back out to the shop and re-shoot the whole top, or can I just re-amalgamate the spots? (i.e. will a "spot" treatment show an inconsistent sheen with the rest of the table)

   I was thinking of re-spraying the area with a 50/50 mix of lacquer thinner and retarder.

   Has anyone had any experience doing this?

   d_l_white wrote:

    I was thinking of re-spraying the area with a 50/50 mix of lacquer thinner and retarder.

   Has anyone had any experience doing this?

     I really have no idea what you expect to accomplish with this, your best bet is to sand it down and rspray it.

1. 
   donkondra1 | Apr 03, 2012 02:33am | #7

   Uh, no..

   Stripping is a much better alternative if that is the chosen "fix"..  All sanding will do is gum up the paper.

   And if the OP isn't interested enough to provide more information, he's on his own.

   Cheers, Don

1. 
   gofigure57 | Apr 03, 2012 07:42am | #8

   Plus one on the no sand ... a card scraper works great on flat surfaces then a light sanding.

   Tom

2. 
   IdahoDon | Apr 05, 2012 12:00am | #14

   I am curious about sanding gumming up your sandpaper - Kelly Moore/Gemini and Chemcraft sand about like nitro lacquer - quickly and easily.  

1. 
   user-64052 | Apr 05, 2012 01:37am | #15

   if your material

   hasn't fully set as the OP stated after 5 days(soft) it would more than likely load up on the sandpaper. I think that trying to sand a finish off rather than stripping it, is like a bear cub playing with it's dick.

   ron

7. 
   IdahoDon | Apr 04, 2012 12:23am | #9

   Yep a good precat lacquer won't act like nitro lacquer so you'll have to sand it down a bit and shoot another coat.

   Having said that, many pre-cat lacquers have the cat as an extra cost and to make the product easier to sell to the price concious consumers they often sell pre-cat without even mentioning the cat!  In those cases your lacquer will probably disolve in lacquer thinner like nitro lacquer would.  A week after a buddy sprayed a casino bar with pre-cat sans the cat, there was some overspray on laminate that came right up with lacquer thinner.

1. 
   donkondra1 | Apr 04, 2012 12:03pm | #10

   Pre-cat is just that, the catalyst has already been added.

   If the catalyst has not been added the product is a post catalyzed lacquer.  

   Two entirely different animals.

   Cheers, Don

1. 
   IdahoDon | Apr 14, 2012 02:22pm | #21

   I have to admit to being wrong about Chem Craft precat being disolved with lacquer thinner - I assumed it was that product, but.....

   Last week I was at the same establishment spraying the project I've worked on for the last 5 weeks and found some of the Chem Craft precat that was used last year - sprayed some on a laminate scrap and two days later lacquer thinner wouldn't touch it.  

   The overspray I wiped off last year must have been either some nitro lacquer the guy was getting rid of on the first finish coat, or simply sanding sealer.  

2. 
   gofigure57 | Apr 04, 2012 11:00pm | #11

   I use a lot of post cat , Lacquer thinner won't budge it.

1. 
   IdahoDon | Apr 04, 2012 11:47pm | #12

   I looked up the product based on some leftover material (I'm just finishing building a bar addition in the same place) and it's Chemcraft Chemguard II (without the optional cat)....and I can say that at least in Reno on this bar that lacquer thinner took the overspray off of a laminate top a week after it was sprayed   (see chemcraft.com/pre-catalyzed)

   Edit:  What kind of funky spam filter is being used here?  WTF? 

   Here's the rest of my post that triggered the spam filter:

   I'm not saying it's not technically precatalized, but I'm saying it has a limited amount of cat (or else they wouldn't be selling additional cat for "higher performance").

1. 
   user-64052 | Apr 05, 2012 12:00am | #13

   the reason that

   the lacquer thinner removed  the lacquer so readily is that perhaps it didn't adhere very well to the laminate.

   ron

8. 
   R Bohn | Apr 05, 2012 10:13am | #16

   I think we are missing the point as far as pre cat / post cat lacquer.  These finishes were designed for kitchen cabinets. They are not easy to repair or remove . It can get all the damage other finishes can but is not designed to be repaired.It is a bad choise for furniture because it cannot repaired. All finishes were designed for a reason, the trick is to match the task with the right finish. For furniture, nitro lacquer, shellac will insure that the furniture you build today, will be repairable and be the family treasure you intend them to be.  Do good work   Randy     Conservator Wood Artifacts

1. 
   roc | Apr 05, 2012 11:17pm | #17

   Right You Are

   R. Bohn,

   Well said.

9. 
   roc | Apr 06, 2012 11:07pm | #18

   The way to go for MOST people

   IdahoDon,

   I hear you.  You are talking the families with kids and people who don't use "protection" and end up with wet what have you on the table.  The people who want to buy tables but don't want to take responsibility for damage they inflict

   For the FINE woodworking crowd here is the other  perspective.

   Relatively durable.

   I did what many would call a mistake and finished our dining table with Shellac/french polish.

   Right after I finished it, a couple of weeks, I pushed my laptop computer across the surface and put a very large V shaped scratch in the table.  I am positive the lacquer would have been scratched in the same way but perhaps to a lesser depth.

   I had to learn my lesson :  Slide nothing across the table; pick it up and place it.

   anyway.

   I whipped out the french polishing accoutrement and before dinner I had repaired the scratch to where it was completely gone and we ate dinner on the table.  No significant fumes.  I didn't have to take the table to the shop or send it to a finisher for repair , let alone sand or strip the whole surface.

   We use place mats, hot pads and coasters.  For us with no slobs in the family the shellac is just great.

   For the slobs and kamikaze kids I recommend a stainless steel table until they get it together.

   In other words the lacquer is still going to scratch even if more water resistant.

1. 
   Westchester | Apr 07, 2012 08:25am | #19

   Big Scratch

   Those Apple computers are dangerous !

   SA

1. 
   roc | Apr 07, 2012 09:12pm | #20

   Ah Ha !

   There is where I made my mistake.

   Neeeever mind.

10. 
    IdahoDon | Apr 14, 2012 02:25pm | #22

    My only other thoughts on this is that I wouldn't sand the whole thing down for a scratch - buff the scratch out, or sand it out and spray a few coats in the buffed out area, followed by block sanding to level the fix, then a coat over the enitre surface to even it out.

11. 
    swannyww | Apr 22, 2012 12:57pm | #23

    Magna shield from hood finishing is a pre cat and allows recoating anytime.  I don't know the brand you used but customer service might be able to tell you about its spefications.