A Glass smooth finish (How do I get)

[Dan Barr]

I would like to solicit any and all methods of putting a glass smooth (and ridiculously shiny) finish on a cocobolo and Maple jewelry box.

Im sealing the cocobolo with shellac first.

thanks,

dan

[Steve Schoene]

Continue on with the shellac, leveling after every 2-3 coats, until you have an perfectly smooth, evenly scratched surface. Make sure that surface has enough thickness to do the rub out process. Sand it in a couple of grits to about 1500 or 2000 grit, and then shift to automotive polishing compound. You will want to end with the finest compound--often called something like swirl remover.

Shellac will take as high a polish as any film I know, and do so without looking like some patent leather plastic.

[Sam Yerardi]

To achieve a glass smooth finish you will need to fill the grain. This can be done with shellac, but it is a long shellac/sand/shellac/sand.... process. An easier way is to use paste or liquid filler. I use paste fillers that I have thinned down with the appropriate solvent. I choose a color close to the backround color of the wood I'm filling. You don't have to do that - you can choose a contrasting color for different effects but for this I would use something close to the color of the wood you're filling. The maple will be very tight grain to begin with so in order to get the optimum fill, you will need to thin it down to a very liquid state. For the cocobolo, the grain is probably going to be a bit coarser, so you can leave the filler thicker. I apply across the grain with a burlap rag, rubbing it in vigorously. I let it completely dry, and then sand it out. I look at the surface with a raking light to see if I can see any grain. If I can then I repeat the process until it is smooth as glass. Then I apply then next or final finishes, whatever I'm going to do next.

[Sam Yerardi]

As Steve suggests, you can stay with the shellac. Since the grain going to be tight to begin with, especially with the maple, the shellac/sand process won't be a huge effort. When you work with woods than have much larger pores like walnut or oak, the filler route may work better UNLESS you are tackling the surface with French Polishing or padding in which case you would probably stay with the shellac.

[Phil Phelps]

Soak your paper for thirty minutes before use in a water bath and a drop or two of ivory soap. Use an automotive foam sanding pad. Sand until you can't move your arm the next day.

[Steven Wilson]

In addition to the above I would be extra careful in preping the wood. I would take your sanding schedule (prior to finish) and extra grade or two. Next, eventhough shellac (and lacquer) dry quickly and hard, you still want to let the finish cure for a couple of weeks (the more the merrier) before rubbing out. Not important if you want semi-gloss, very important if you want a very high gloss. You will need to be very carefull on how you apply the last couple of coats. Take your time and make sure you leave a perfectly level finish. Every finish imperfection will show when you rub it out.

[Dan Barr]

Thank you all,

im formulating my plan based on your advice.

I got the multi-pack of cloth abrasives ranging from 1500-12000 grit.

Here's my idea thus far:

-Pore filler (all finish surfaces of pieces prior to assembly)
-Sand and apply pore filler on any remaining open pores
-Waterlox on the maple (2 coats lightly rubbed with 0000 steel wool)
-1-2 coats of shellac followed by 1500 grit wet rub (pre-leveling)
-Assembly and cure for 1-2 days
-3-6 more coats shellac followed by 1500-2000 grit wet rub between coats with a cure time between coats of ________________? guessing 1 day here.

Final coat wet rubbed up to 12000 grit or arm failure. whichever occurs first. :D

Is this sound?

Will this give me the "glass" surface im after?

as always,

Thanks for your time and advice.

Dan

[Steve Schoene]

I think you can simplify your schedule quite a bit and still achieve top notch results.

First thing is pore filler. Neither maple nor cocobolo have open pores, like you would find on mahogany or oak, that need filling. The first coat of finish will deal with the very small pores you find in these woods.

I also question how possible it is to pre-finish before assembly. The panels in a frame and panel construction can be pre-finished, but otherwise I'm not very fond of pre-finishing because it makes it difficult to "adust" the surfaces after gluing. There is always some joint that doesn't quite come together exactly as planned.

I suppose the Waterlox in the schedule is to "pop" the grain in the maple. But it's that step that causes you to pre-finish, I presume, because of the danger of an oil based finish not drying well on the cocobolo. I suggest you do a quick test on your maple. Look and the effect of shellac alone compared to shellac over Waterlox, or shellac over BLO. Unless you are using a super blonde shellac, I doubt you will see much difference. Not enough anyway to complicate the assembly process so much.

In any event, don't use 0000 steel wool between coats. The tiny steel shards want to say in the finish and create a bit of a problem down the road. Besides unless you use a specialty steel wool such as Liberion it is likely to have oil on it to prevent rust. Oil and finishes aren't a good match. It has a place on a final coat if you were rubbing only to satin.

So I'd adjust your schedule to prefinish only floating panels if you have them. Then I'd use one of the darker shellacs, mixed freshly from flakes, to start the finishing process. Sand with about 320 grit paper after every few coats to eliminate any defects and level the surface. Padded sanding blocks are very useful in the leveling process. You have to gausge how much shellac to apply. You need enough so you can level without cutting through, but not much more. Then after you have leveled so that all the surfaces have been evenly dulled by the 320 grit, I usually apply one more coat to give enough material for the final rubbing out. I like to give 3-4 days of "curing" here. Shellac is an evaporative finish and doesn't really cure, but I am convinced that there is somehting going on that takes a few days to insure all the solvents have evaporated.

At this point you can start sanding again at about 400 or 600 grit. And sand progressively to where ever you want to stop.--I never go beyond about 1200 grit on the CAMI system or about 2500 on the P system before I shift to polishing compound. You can finish with progressively finer grits of paper instead of shifting but most people prefer to go the the compound for the final steps. Work where you have plenty of light, including some at a low raking angle, so you can really see any scratches.

No reason for your arm to fall off. If you go progressively through each grit with no skipping it will take only a few minutes with each grit to sand out the marks of the preceeding grit. There is no benefit in sanding (or polishing) more than that.

[Larry Fox]

I would say that French Polish would be just the ticket here.

[Steve Schoene]

Larry could well be right. If you have smooth flush surfaces without lots of nooks and crannies, French polish would give the ultimate surface. High gloss, very clear and "deep" in one sense, but at the same time giving the appearance of almost no thickness of the film.

That's a different dissertation on process but French polished surfaces are wonderful, and thought by many to give the ultimate finish. You will come close to working your arm off doing this, and you would want to do a practice board or two before starting on an actual project.

[Dan Barr]

thanks for the tip on the steel wool. i noticed that same thing a while back and should have remembered.

as for the waterlox, im going to stick with it because of the color it gives the maple. i already tried BLO/shellac and shellac alone. i just like the waterlox on these particular pieces.

i'll probably reduce my sanding schedule as suggested. i know i dont need to overkill, but i was prepared to go that far though.

thanks again.

dan