# Finishing with CA glue



## RussFairfield (May 2, 2009)

There have been a lot of questions about finishing problems with CA glue. The real problem in most cases is one of their expectations, and not a problem with the CA glue or its application. 

A common problem with the CA finish is that people expect to apply the CA glue to the wood and Voila!! - Instant shine. What they will get is a smooth low gloss matte surface, or a glossy but rough surface. Either requires that the finish be finished - additional sanding and polishing to get a smooth surface and a high gloss. 

You should expect to do with every CA finish what someone said they did to fix an uneven and blotchy CA finish- sand with 400 and 600 to make sure it is smooth with NO imperfections, and then polishing it with 4000 to 12,000 Micro-Mesh, or buffing with White Diamond, and whatever else you want to do that is similar. 

The only finish that I know of that will leave a smooth high gloss every time right off the applicator is a shellac friction polish and sometimes a dipped lacquer. Everything else needs a little sanding and polishing to finish the finish. Some folks can get the smooth gloss without additional polishing the other finishes, but they are the exception rather than the rule. The rest of us have to sand and polish the surface (finish the finish) to get the smooth gloss.


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## USAFVET98 (May 2, 2009)

Russ,
   How many coats of ca do you recomend? Is it just ca or ca/blo? Do you start back from 400 after each coat? I know it's a lot of questions, but I figure I ask while your here. 

Thanks in advance
    brian


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## RussFairfield (May 2, 2009)

I have never put my use of CA glue to words, so this is a 1st, but it is pretty simple so there isn't anything important to leave out. It is minimal effort and probly not much different from what Cav described in an earlier post. There are at least 300,000 ways to put on a CA finish, and I swear that I have read every one of them described on this site over the years. Now I am adding mine. 

CA glue isn't any different from any other finish. We sand the wood smooth, put the finish on the wood, let it dry or cure, sand again, repeat as many times as necessary, and then polish the final coat to whatever degree of gloss we want. The only difference is that CA dries faster and is a harder finish than most other things we can put on the pen. The only thing harder is Enduro when done properly, and a coat of pure acrylic plastic. Other than that, it is just another finish and there is nothing magic about it.

Here is how I do it. I use a couple slightly different applications of a CA glue finish. 

I make the final cuts with a sharp skew chisel because the smoother surface requires less sanding.

On all wood I sand with 220-grit, and then apply a liberal coat of thin CA glue to harden the wood and fill the grain. I don't use any of the super dense exotics like Cocobolo and such because I am allergic to them.  On really soft wood that soaks up a lot of glue, I drip the CA glue onto the wood and smooth it out with a paper towel. Run lathe at no more than 1000 RPM or I will get glue in my face. Then I sand back to the bare wood with 220, and then go to 320, 400, and 600.

On porous wood, wood with little holes and voids, or wood with a coarse open grain - I sand with 150-grit to clean up the surface, and then wet-sand with 150-grit and medium CA glue. The 150 creates a slurry of wood dust and glue that fills in the voids. I keep sanding until the glue hardens. Then go to a clean spot on the sandpaper and smooth out the rough surface. Repeat if necessary. Then sand up to 600 grit. 

I use 150 grit for the wet sanding because it will cut through the medium CA glue and make a slurry of sanding dust and 220 grit will skate over the top of the glue. 

There is a final inspection and sanding if necessary to make sure there are no voids or dimples in the surface. No magnification. If I can't see it with a bright incandescent light, it doesn't exist. I go back to 320grit if that is what is necessary to get a smooth surface faster. Then sand back to 400 and 600. 

Now the wood is ready for the finish. This preparation is the same regardless of what finish I am putting ojn the wood. I show this on my website as the sealer under a friction polish.

If the finish is to be a CA glue, I use plain medium CA glue, no oil, if I want a high gloss finish, and 2 thick coats applied with a paper towel folded to 8 thicknesses. The only difference between thin and medium is that the thin cures faster, but I can put on a thicker coat of medium. The thin cures to a smoother surface and requires less sanding, but it takes more coats to get the same thickness. In the end it takes about the same time, but I use the medium because it doesn't soak through the paper towel and the thin does. 

The surface is kinda rough when the glue has dried, so I have to sand in between coats to get back to a smooth surface. That is usually 320, followed by 400 and 600 grits. Then the 2nd coat of medium CA glue with the same sanding to get back to a smooth surface. 

If I want a soft gloss, I polish it with 0000-steel wool, give it a coat of wax and it's done. Some people like them that way. 

If I want a higher gloss, I polish it with the 0000-steel wool and then go to 4000, 6000, 8000, and 12,000 Micro Mesh used dry. Then a light coat of Renaissance Wax and that's it. Sometimes I use the HUT polish after the 12,000 if it looks like it could use a bit more gloss. 

The entire process takes no more than 10-minutes.

The only reason I would use the BLO at all is to get a smoother surface on the 2 coats of CA glue. The sanding between coats isn't eliminated, but all that is required is a quick lick with 600 to smooth it up and pick up any residual BLO before putting on the 2nd coat. The final coat will usually be a soft gloss that is ready to go as it is. If I want a higher gloss, I leave it overnight for the BLO to cure, and then sand from 600 throiugh the 12,000 Micro Mesh to get to the same gloss as the straight CA glue. 

I expect the finish to be a matte when using the BLO because there are oil molecules in the surface and an oil makes any finish have a duller gloss than if it weren't there. I could use any other oil for the same thing. Mineral Oil works, but the non-curing oil will always be an imbedded liquid in the surface and the finish can never be polished to as high a gloss as with a cured oil or no oil at all.

In the end, there is no need for the BLO. The CA applied to a 600-grit surface does just as much grain popping, and using the BLO doesn't save a lot of time unless I want a matte finish on the pen. I use it more to demonstrate to others on how to do it than I do as a finish.

My reasoning for not putting BLO on the bare wood goes back to the beginning of my using CA glue to harden and fill the wood, and I have never seen any need to do it any different.  I reasoned that if I were to use the BLO on the bare wood, I don't get any penetration of the thin CA glue because the wood is already filled with the oil. I would rather have the wood filled with CA than BLO because the CA is harder. When I have filled and sealed the wood with a CA glue, I could see no benefit for putting a layer of oil between the layers of glue and compromising the bond between them. 

I know others will argue that putting the BLO under the CA is the only way to do it. But, you asked how I apply a CA finish, not how they do it.


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## george (May 2, 2009)

Great advices; doe I have your DVD, I have read few new things that I will try in near future. Thanks for your time.


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## leehljp (May 2, 2009)

Thanks Russ for this. I have been looking for a previous post of yours that gave the "Enduro" statement above. I want to include a link to that in the next revision of my PDF file - that I greet new members with.

While you don't mention it and probably don't see a need for it - I have used BLO on occasion on some woods to give the amber color that oils give (Pop the grain as some mention). I suspect that a single coat of poly would do the same and be less "oily" in addition. Your reluctance and reason for not using BLO directly on the wood makes me think that any quick drying finish like poly, shellac or other slightly amber tone - would be better for the so called "popping the grain". I certainly don't use BLO or other oil on holly or oily woods for sure.

Thank you for your input and your willingness to help so many here. It has sure helped me quite a bit.


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## workinforwood (May 2, 2009)

Great thoughts Russ.  I've met a lot of people that seem to think you put the glue on and the pen is super smooth and shiny.  I spray acrylic urethane on most my pens, which is basically pure plastic, and I still expect to wet sand and polish just like anything else.  The only difference is there won't be any ridges and the dimples are super small, but still dimples non the less.  Any spray finish will have dimpling caused by the impact of the finish and air combination hitting the hard surface, combined with the amount of drying agent in the finish.  Gloss is all about how much reflection in the finish you can achieve.  It doesn't matter if you use CA, or if you use a satin, semi or high gloss acrylic or polyurethane product.  A satin poly for example is called satin because it lays out with a higher content of drying agent, which in turn creates more micro dimples in the finish.  The micro dimples cause less light deflection. If you polish a satin spray finish, it will become a gloss finish.  You go to a bar and you see a deep gloss finish on the bar top.  That's 50 coat resin, but it doens't just lay out and shine, you have to remove the ridges, sand and polish it to get that deep clean shine.  The high class laquer corner tables that you find in expensive furniture stores..same thing, a multitude of coats of laquer and a ton of polishing.  That's the bottom line..a finish isn't finished just cause the finish is applied to the wood.  Application is the easy part.

   Another thought is strength.  I too do not want to debate the best finish, as all finishes have postives and negatives, but there is a difference between strength and hardness.   The have completely different meanings.  The harder something is, can make it become weaker.  CA might be the hardest finish you can ever find, I do not know if there is something harder.  Acrylic urethane however, is probably the strongest finish you can find.  In order to have strength, you must have flexibility.  It is like comparing PR to urethane resin.  A urethane resin is stronger than PR.  Doesn't mean it's better, as you have to give up one thing to obtain another.  An acrylic urethane finish will not polish quite as high as CA, although it can get extremely close, it just doesn'tt quite make it, but the acrylic urethane will outlast CA for endurance, and it will expand and contract with the wood.  CA being slightly harder will get you that slightly deeper shine, but if the wood hits the floor it can crack the finish, if the wood expands, the CA has no give due to it's hardness factor.  CA will not allow any moisture in the wood to escape, so if you make a pen on a humid day perhaps, then your wood might have an extra percent of moisture in it and if that moisture tries to leave, it will be trapped behind the CA creating a cloud, much like a water ring on a laquer table.  An acrylic urethane will allow the water to leave. If you clean a CA pen with most everyday household cleaners, it'll look great.  An acrylic urethane will be destroyed by harsh cleaners or alcohol.  Adding BLO to CA, definitely cuts down on the hardness, but I find it also weakens it in the strength category as well.  Acrylics can be catalysed, which will up the hardness factor, but as I said, you add more hardness, you give up your strength.


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## DurocShark (May 3, 2009)

Thanks Russ. I like the emphasis on prepping the wood before finishing. That's the part missing from most finishing discussions.

I would like to note that I do occasionally use blo, but it's used as a lubricant and accelerant. It allows the use of CA in situations where it would be impractical. Such as 9 months out of the year here. ;-)


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## wdcav1952 (May 4, 2009)

Great thread.  Thank you Russ for starting it.  You and Jeff made some excellent points.  I  had never considered that the BLO might weaken the CA.  I  gave up the CA/BLO because all I knew was that I got a better finish without the BLO.


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## Bikerdad (May 4, 2009)

workinforwood said:


> Gloss is all about how much reflection in the finish you can achieve. It doesn't matter if you use CA, or if you use a satin, semi or high gloss acrylic or polyurethane product. A satin poly for example is called satin because it lays out with a higher content of drying agent, which in turn creates more micro dimples in the finish. The micro dimples cause less light deflection. If you polish a satin spray finish, it will become a gloss finish.


  It does matter, a lot.  All clear finishes start out at the factory with the same "base", a clear gloss.  Semi-gloss and satin have flatting agents added.  It does not matter how much you sand or "polish" these, you cannot raise their gloss.  The flatting agents are micro particulates (usually silica, IIRC), and since they are part of the finish, you can't polish them out.  An absolutely scratch free satin finish will not have as much shine as an absolutely scratch free gloss.  On the other hand, as your statements imply you CAN lower the gloss of a high gloss finish, simply by leaving a more "aggressive" scratch pattern, i.e., don't go as far in the sanding/polishing regimen.


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## Manny (May 6, 2009)

Love this topic. 

I would suggest cross sanding after each grit (both sand paper and micromesh) before and after coating. If you see any scratchs at any point go back a grit and work them out then move on. 

Manny


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## RussFairfield (May 6, 2009)

Thanks, Manny. That's the one detail I left out. Sanding in both directions is a good thing with ALL grits, even the 12,000 Micro-Mesh. 

And trying to remove scratches with a finer grit is always an exercise in futility. The most difficult decision for all woodturnewrs is going back to a coarser sanding grit and starting over.


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