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Pre-Catalyzed Lacquers vs. Polyurethane coating for furniture

Pre-Catalyzed Lacquers vs. Polyurethane coatings for furniture

 

Pre-catalyzed lacquers have been a great invention, they look great and are harder and tougher than regular lacquers, but they have some draw backs and aren’t always the solution to your finishing needs.

 

A pre-catalyzed lacquer is a formulation that has an additional catalyst added to it at the factory that makes it harden when it cures. You can smell the difference in-between regular lacquer and a Pre-Cat as the Pre-Cat has a distinctly more acrid smell. That’s the acid additive that when applied reacts with the air and the other solvents in the mix to make a chemical cure as appose to just an air dry cure. The benefit is a tougher and more water resistant finish.

 

It has the look and feel of a Lacquer but will yellow over time. Some more than others the better the material the less it will yellow. With the exception of one lacquer I know they all do this. Another problem I have had with all pre-cats is that as they are exceptionally harder (that’s  a good thing for abrasion ) they also have the higher tendency to crack on the joints of the cabinet doors and where raided panels have there connection to frame of the door.

 

The draw back is that it’s not and impervious coating which I guess, you could say about any coating but that being said I have had customers tell me that they have had call backs with panels in font of sinks that needed finish repair after a year.

 

What’s the solution? I have found there to be two good solutions  Conversion varnishes of which I have found a water based version that at this time appears to be doing as good as the solvent based version and then there are the polyurethanes which have become my choice of materials. They are more expensive, and harder to handle being a two part material (it comes in two cans and you have to mix one with the other in the right amounts) and it has a pot life, that means that it is going to harden up on you if you let it sit in your spray gun more than about 4 hours.  

 

 Those are the down side to the material.  On the up side you have a finish that doesn’t yellow with age and it hard enough to be use for exterior applications. For example front doors exterior wood trim and wooden patio furniture and as a poly it is made with a certain amount of elasticity, the ability to stretch. Wood will expand and contract with temperature and moisture so you want a coating that will do the same. 

 

I have one customer that used the material very successfully on high end pool furniture   for a classy roof top bar in down town LA.

 

Classically where finishers have finish failures is on the doors in form to of the sinks water splashes out and then isn’t cleaned up after wards. It tends to puddle on the trim and after a while will work its way under the finish and then peels.

 

Two of my highest end finishers are looking at switching to the polyurethane exclusively and while that is something that they can do being as large as they are. What the smaller shops can do that  doesn’t generate the higher costs and yet prevents the call backs is to do the high water areas in the polyurethane and the rest of the kitchen in the Pre-catalyzed materials. 

 

 I  am a sales and service  rep for several different manufactures and would be happy to recommend materials to any one that asks, The Great thing about my job is that I push the products that work the best rather than being constrained to on brand of material I have several and I’m always  looking for new and better.

 

Best,

 

Greg Saunders

ANNEX  PAINT and LACQUER

7450 Reseda Blvd.

Reseda California 91335

818-344-3000

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October 25, 2008 - Posted by | Conversion varnish, polyurethane, Wood finishing | , ,

16 Comments »

  1. Thanks for this post, I’ll have to keep it bookmarked so I can link it when some loony throws up on my blog.

    Comment by elinorloewen | January 9, 2009

  2. ok what ever you need to protect your funiture we can figure it out for you. generally I put the pukers in the tub in the bathroom. There is tile and porcline there and I have no doubt it is impervioius to what ever might come up. On other hand you might watch the people you invite over if there prone to puking then I wouldn’t have them over.

    Comment by Greg Saunders | January 12, 2009

  3. Is pre-catalyzed lacquer being used by the Amish furniture-makers and the (almost bankrupt, “struggling-to-stay-alive” motor home manufacturers) in Indiana and Ohio, for the coatings on their tables, chairs, & cupboard cabinetry?

    I know a furniture retailer, who sells out of his store, who won’t reveal what products the Amish use. It’s supposedly a SECRET! LOL In my experience, if more than one person knows something … it won’t be a secret.

    Comment by G. L. Forsmo | March 25, 2009

  4. HI G.L.,
    Sorry I have no Idea what the amish furniture makers are using these days or what they used in the past for that matter. I would try googleing the matter and see what you find

    Best,. Greg

    Comment by Greg Saunders | March 25, 2009

  5. I’m just finishing up building a bunch of library cabinets. I used quarter sawn white oak and have been looking at different finishing products. I’m thinking about using a dye and a filler then a final finish with polyurethane. I have a new HVLP system and would like a professional looking finish.
    The library has a built in desk with a veneered top and will probably get about as much use as a dining table. Do you have any suggestions for a finish. I like the low toxicity of water based finishes but have had poor luck with them in the past, and they are a real pain to clean out of the gun.

    Comment by Steve Smith | August 11, 2009

  6. Hi Steve,
    I have found the Renner brand of water based materials to be far and above the best around, they an Italian Import the only draw back it that it is priced like a Ferrari, on the plus it is 80% solids so you as apposed to the Lacquer based products that rarely get above 25% solids. the point being that you get greater square foot coverage. Renner has a interior poly that is tougher than nails and fairly easy to work with. Gemini, an American Company has another product call Titanium water based coating that is very good as well. It is a “modified water based acrylic urethane which is not as expensive and yet tough. there are a few thing to know about Water based materials. For one as they are thicker they require a larger tip size to have it spray out well. I have seen more than one finisher think the materials were bad because they used two small a tip size and or so much pressure to get it out of the gun (either through conventional HVLP or a Air assisted airless) that actually sheered the materials on a molecular level which produced a very grainy surface. The other thing with any and all W/B materials is that they take a while to fully cure and until then are soft. after a full 30 days they are harder and more moisture resistant than lacquers but until then you have to be gentle. example I had a guy do a dinning room table with the Gemini and it looked great, he delivered it the day after it was finished, then customer had a party where there were a lot of drinking glass rings left in the finish. needless to say everybody was upset. Another finisher did a High end cafeteria counters with the same product but (fortunately) waited several weeks before install then more time went buy before the abuse hit it and the finish held up for two years looking brand new. when they remolded the place they used the same counter tops. They cleaned them up, wet sanded them then buffed them to look like they were new.
    As far as clean up of water based things: warm soap and water after you have used your guns works the best. Acetone However, with turn the stuff into Glue which is complete hell to get off. (been there and done that) There is an article on the blog about the Homeowner that did his Kitchen in the Gemini White, It turned out great but a few days after the finish went on the wife cleaned a spill with 409 and that ate clean through to the wood, needless to say the freaked out. They wanted to sue me for the cost of the material all the labor and to redo the entire Job, We touched up the spot and got them to wait a few more weeks and all was well.

    As far as the dye and the fillers go, I would play around with the dyes and stains and see what look you want to have. The Dyes are a little more flat and are a tint where as the stains give you a little more “grain pop” which would be a nice thing on the 1/4 sawn oak. As for filler I would suggest a Clear high build Polyester primer. that builds up and fills the grain on top of which you can put a top coat of most anything you want water based or other wise. If you want Glass smooth and industrial/commercial Hard do the polyester primer and then the polyurethane topcoat either solvent or W/B. These products are professional products and I would recommend doing a few test/practice panels first if you are new to the finishing game.

    best of luck send me pictures if you will.

    Greg

    Comment by Greg Saunders | August 12, 2009

  7. Greg,
    Thanks for all your great advice. I have a lot invested in this project so I’m happy to spend a few extra dollars to get a great finish and I’m not pressed to make a profit or keep to a tight budget. I’m going to give the Renner a try as it sounds like a great product and I’ll experiment with the tip size before shooting the final finish.
    I’ll send photos when done!

    Steve

    Comment by Steve Smith | August 15, 2009

  8. Hi Steve,
    Glad to hear it, You’ll be happy you did. you can send me a message to greg@annexpaint.com when you are ready to order.
    Best,
    Greg

    Comment by Greg Saunders | August 18, 2009

  9. We absolutely love your blog and find most of
    your post’s to be exactly I’m looking for. Does one
    offer guest writers to write content in your case? I wouldn’t mind writing a post or elaborating on some of the subjects you
    write concerning here. Again, awesome blog!

    Comment by www.bati.szczecin.pl | February 3, 2014

  10. I wouldn’t mind posting your article I would have to approve them first and of course they would have to be on topic. what is it that you would like to write??

    Greg

    Comment by Greg Saunders | February 19, 2014

  11. Greg thanks for the advice..

    Comment by Mike Woodworth | September 10, 2015

  12. Greg,
    I am building kitchen doors and drawer fronts for our new kitchen. The drawer fronts are completed and I have almost completed the first door. As a hobbyist without a dedicated finishing area, I cannot spray a finish inside my one car garage because my shop is in our basement. I am using an Omega stain (from the company that made the cabinet carcasses) which looks like a Varathane Gunstock stain. The wood is quarter-sawn white oak. So far my process has been to apply the stain, wait overnight, spray 3-4 coats of Mohawk E-Z Vinyl Sealer (M102-8000), apply Minwax Satin wipe on-poly, wait about 24 hours, lightly sand and repeat the polyurathane process three more times for a total of four coats of wipe-on poly. The results are beautiful but is time consuming. However, here is my problem: The stain requrires a barrier before applying the poly because the wipe-on poly will lift the stain off the wood – even after waiting 24 hours. Thus I use the Mohawk E-Z Vinyl Sealer which CANNOT be sprayed indoors. Here in western North Carolina Fall is in the air and my days of spraying the Vinyl Sealer are numbered. So, I went to my local woodworking store and was told that Mohawk Pre-Catlyzed Clear Lacquer Satin (M102-0412) would provide just as much protection as the wipe-on poly. I have tried a test peice and the results are great – especially since the lacquer dries in 30 minutes. In a kitchen, can I use the lacquer instead of the poly and do I need to apply the Vinyl Sealer first. Also, how many coats of the lacquer do you recommend?
    Thanks,
    Steve

    Comment by Steve | October 28, 2015

  13. Hi Steve,
    well done on your work, I don’t know that the pre-cat lacquer is going to give you as much protection as the Mini wax wipe on poly, I have never been a big fan of the minwax line but that being said I have had several people report good result, “poly” is like saying “soda” its pretty generic and manufactures have a lot of latitude in what they can get away with calling a poly, But again I have had several good comments about it. to get to your question, yes you would need to have the vinyl sealer under the pre-cat. I have found that is a key to using the Pre-cats at lease two good coats of vinyl sealer sanding in-between and making sure to catch the edges well and then two coats of the pre-Cat. with a scuff sand in-btween. If the poly is in fact a poly it will not yellow on you over the year where as the pre-cat and any lacquer product will not much but a bit, generally you don’t notice it especially if the stain is dark. But if you are doing 1/2 the doors with one process and the other half with another process you might begin to see a slight ambering difference in a few years, especially if there is a lot of sun light in the room.
    Hope that helps. Let me know how it turns out

    Greg

    Comment by Greg Saunders | October 30, 2015

  14. Thanks for the information. This has been a huge learning curve. I’ll let you know what I eventually use and how it turns out.
    Steve

    Comment by Steve | October 30, 2015

  15. What is the best hardy end coat/finish for a soft wood camphor laurel slab dining table with a mat finish for a household that is hard on their furnature please

    Comment by Jane WEEKES | November 7, 2017

  16. a Two component polyurethane, by that I mean a polyurethane that has a part A and a part B that you mix together, you’ll find single component products on the shelf that say polyurethane they are not the same. there are water based polyurethanes and solvent based products I carry both in my store. when using these products you should have some spray experience or be willing to learn how to spray or Hire a professional. Automotive Clear Coats are polyurethanes but you’ll want a clearcoat designed for wood. the Pinnacle brand is what we have and has proven its self over the years, you can see several videos on it on the blog. If you are in California you are somewhat restricted in what you can use. if you are elsewhere you have more choices as the restrictions are less.
    Best of luck,

    Greg

    Comment by Greg Saunders | November 8, 2017


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