CA over Laquer?

[jking]

I know most have one or two types of finishes they prefer to use. Many use thin CA as a sanding sealer before applying the final finish. I'm curious if anyone has tried CA over a laquer finish? Would this provide a compromise of the look of a laquer finish with the durability of CA? I suppose there's probably some potential issues if the laquer has fully cured.

 

[IPD_Mrs]

John,
I am not sure if you will have chemical issues such as you do with lacquer and polyurethane. (I know you can't put one of the other but I forget which it is) Really I am not sure what you are trying to accomplish. A lacquer finish can look anywhere from satin to high gloss as can CA. It is based on your finish on the finish!!!

Mike

 

[ed4copies]

You would accomplish time savings.

A good lacquer finish takes days, sometimes weeks. CA is much faster.

Are you really saying you started a lacquer finish and would now like to get it done much more quickly so you are considering going over it with CA???

Been there, have NOT yet done that!!!

 

[redfishsc]

As a professional finisher, we have an axiom that we live by that says "never put a harder finish over a softer finish".

Lacquer is, by finisher terms, a lot softer than CA.

If you have a pen with a lacquer finish you would rather have a CA finish, just sand off the lacquer with the lathe.


The main difference between the look of lacquer and CA is that most lacquers will impart a slight yellow color (more than you might think) especially over time. CA does not.


If you are looking for a more durable finish than lacquer, do a Google search for "precatalyzed" lacquer distributors in your area. I know Mohawk sells an aerosol can of precat that seems to be pretty good.

Here's the deal, though-- precat is only a little big harder than regular nitrocellulose lacquer, but it is a lot more chemically resistant which is, IMO, the bigger of the two issues with pens.

Every finish will scratch if you scrape it with keys or drop it, but not every finish will stand up to sweaty hands. Precat will. That, and you can assemble your pen the next day after spraying.

 

[cbonner]

Redfishsc drove the nail home...

If you want to speed up the process, use the CA first, then finish with lacquer. Using thin CA, you are adding coats near constantly and can pretty rapidly fill the pores. As an added benifit, I think the initial CA coats help to stabilize the wood and prevent cracking.

I can't back it up with hard evidence, or tons of professional experience, but I think the lacquer holds up better to the normal wear and tear a pen experiences. Because of this, I like my pens to have final finishes of lacquer.

My current finishing process (when I am pursuing a glassy finish) starts with 10-15 coats of thin CA, sanding between coats (sometimes I will throw in a couple coats of Medium CA, but it takes longer to cure). I then put 3 coats of Mohawk pre-cat lacquer sanding sealer, sanding between coats. I finish with 3+ coats of Mohawk pre-cat gloss lacquer, sanding between coats and stopping when I am happy with the finish. I final sand with 2000 and 4000 MM and polish with an automotive machine polish.

 

[RussFairfield]

You are essentially putting a CA finish over a sanding sealer, and you can expect the same risks as when doing that.

Most people use sanding sealers that are a lacquer with a lubricant added to them so you can sand without the lacquer balling up on the sandpaper. A sanding sealer is intended to be sanded back to the bare wood so it is IN the wood, not ON the wood. Read the directions on the can. That is why the lubricant is there.

A lot of people use the sanding sealer to build up a heavy film finish before they apply another finish on top of it, and some are using the sanding sealer as the finish. However, a lot of those are wondering why they are having problems with their CA finishes. In the first case, nothing sticks to lacquer very well, except more lacquer which melts into the previous surface. In the later, the lubricant in the sanding sealer makes it into a very soft finish that can be polished to a high shine, but is too soft to wear very well. There folks would be better off with a shellac friction polish because it is harder than the sanding sealer.

So, consider your lacquer as a grain filler and wood sealer, and do what Redfish said - sand it back to bare wood. Then apply the CA finish. There is no benefit to leaving the thick lacquer film under the CA, and you can have a lot of problens with it. The coating of CA will effectively destroy all of the transparent and reflective qualities of the lacquer, so there is nothing there to save.

There are shellac based sealers available, or you can use pure shellac. It sands quite easilly. CA, and all other finishes, stick quite well to shellac. You can apply the CA over a film of shellac on the wood and expect it to stay there, but not so with lacquer.

 

[RussFairfield]

Originally posted by cbonner


I can't back it up with hard evidence, or tons of professional experience, but I think the lacquer holds up better to the normal wear and tear a pen experiences. Because of this, I like my pens to have final finishes of lacquer.

ANY finish will wear better and be more durable when it has a harder surface on the wood under it. I have been using a shellac friction polish over a CA sealer for years. The softer shellac will wear many times longer than if it were applied to the softer bare wood. The same is ture for lacquer. I started doing this because it was easier and faster to get a higher gloss than with CA glue alone. Then I discovered that it was a more durable finish that way.

 

[dcavazos]

BLO The Proper Way / BLO as a Finish

In order to have the best result preparation and time it needed in order to apply the BLO finish to any wood pen.

This is just an abstract of the way that I do the finish on my pens and I will have a full article and instructions in a near future to share this application

After the pen is finish (live the diameter a little thick than the bushings) proceed with the following sanding sequence 100-120-220-320-400-600-800-0000 then the 0000 Steel wool (if you have 800 and 0000 sandpaper available)

Stop the lathe and remove the bushings; Using pain tape mask the bushings to prevent the CA glue to damage the diameter of the bushings

Set the mandrel with the blanks and masked bushings.

Cut a paper towel and make an shape it into a rectangular shape about 1 inch and the length will be the length of the paper towel

Turn on the lathe and apply a thin coat of the BLO (with no CA glue) into the pen; this will eliminate the dust and will prepare the pen for the BLO/CA Glue

Reduce the speed of the lathe, wet the paper towel and apply the BLO to the pen blank
Then apply the CA Glue and increase the speed of the lathe. Move the paper towel form one end to the other end of the pen blank.

After 30-45 seconds you will feel that the paper towel is hot and that the glue is hard. Reduce the speed of the lathe and do the same procedure to the other blank

My recommendation is that after 2 or three coats of the BLO/CA Glue sand the blanks using 0000 Steel wool with a light touch of BLO Oil

Another recommendation is that the amount of coats be an impair number (3,5,7) and every 2 coats sand the blanks using the steel wool with oil

My next step is to buff the blanks using the 2 PPP (Perfect Pen Polish) First the Dark, No Gloss and then the High Gloss

I leave the lathe running for 3-5 minutes in so the glue can be dry and hard; some times I use the hot air gun just for 30-45 seconds (cracks on the CA Glue my appear)

The no gloss PPP is apply direct to the blanks on the lathe and also to the buffing wheel;
I use a pair of buffing disks to clear pens and another for dark pens (another for acrylics)

My buffing procedure is to use the outer perimeter of the wheel; I start with the left side wheel and I move the mandrel from top to bottom and also moving my mandrel 360 degrees.

After 3 to 4 full turns, I apply the high gloss PPP to the other disk and I use the outer perimeter (the right side) 3-4 times (same as the left no gloss side)

When the pen is ready for assembly, I remove the blanks from the mandrel and I use the
Lateral face of the buffing wheel to remove any CA/BLO or PPP form the edge of the pen this procedure makes a perfect cleaning to the face of the pen and this will prevent gaps or bad assemblies of the pen components

No Friction polish is needed the high gloss will remain and will be better than the oily finish of the friction polish

Send me an email so I can send the PDF file with pictures of this application
And also send me your comments

 

[wdcav1952]

David,

You have posted this same thing three separate times. I find that to be plenty of exposure. There are very good articles in the site library on applying a BLO/CA finish if anyone desires more knowledge on the subject. While there are some good points in your rather detailed "abstract" there are other parts of it with which I find myself in less than total agreement.

If you continue to post nothing but your opinions on the subject of CA and your "abstract" there are those of us who would begin to question your motives in doing so.