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Discussion Starter · #1 ·
I am making a clock out of 5/4 mahogany, and I really want it have a very high-gloss surface, like glass when I am finished.

I have some 6"x6" scraps im testing some finishes on. I'm using tung oil and it seems to bring out the grain and look of the wood very nicely.

I ordered the clock parts from KlockKits.com. They had a product called KraftKote Clear Polymer Resin. Does anyone know much about this product? I was thinking I would try and put 5 or 6 coats of tung oil, then pour this resin stuff to put a hard shiny surface on top.

I really dont have much experience in finishing so any tips would be greatly appreciated!! Thanks!
 

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Mahogany is a very porous open grained wood. Oil alone will be next to difficult to achieve a "glass like" finish. Each application will take several days to dry (cure), and the grain will still show irregularities. There are a few techniques that will produce a finish with enough "build" giving the appearance you might like. You should experiment with these to see which one you prefer.

There are several types of sanding sealers available for the base of the topcoat you chose, i.e., lacquer, oil base, or water based. The sealer can be applied in a few coats and sanded in between with 320x when dry. The topcoat being either lacquer or oilbase polyurethane, or waterbase polyurethane will then be applied in enough coats, sanded in between coats to give the "gloss". You may have achieved the desired finish at this stage. If not, and you have enough build with the topcoats, you can wet sand the finish with wet-or-dry (silicon carbide) sandpaper starting with 320x and finish up to 1200x to 2000x and then rub out with compounds like pumice, rottenstone, or automotive compounds all of these available in varying degrees of grits.

The oil base polyurethane will darken the wood (amberish color). It can be wiped on, sprayed, or brushed. If wiped on, thin the first few applications with either mineral spirits or naptha (faster dry). If spraying, being heavily bodied and a long dry time, be careful of runs. Lacquer can be brushed (by retarding it), but works best when sprayed. Waterbased can be wiped on, brushed, but also works best when sprayed.

The above methods can be cut short by using a "paste wood filler", not to be confused with a wood filler putty. It, like the sealers is also available in the different "bases" to be compatible with the topcoat being used. The directions for using this should be followed closely.This will fill the grain and provide a non porous surface to apply the topcoats.

Shellac can be used and works as a good sealer all by itself. It dries fast and can be re-applied as needed to get the "gloss". It too should be sanded between coats so the previous imperfections don't "read" through to the topcoat.

The two part epoxy based (pour on) type finish is a high build finish that may only require a minimum of applications. You will have to apply it and let it sit/drain off for the surfaces you cover at a time. The run-off can be sanded off after the coat has been cured. Following the instructions is critical. As in any finish the topcoat material should not be shaken which may induce air/bubbles into the mix.

It would be advisable to make samples and take them to the final finish you are applying to see the results.
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I can't add anything to that except to make sure to pack the pores.Don't think you can skip this process and get anything like glass.I made that mistake ONCE.By the way you can dye the pore packer,lets say black,and the pores in the wood will be black forming their own pattern and design.
Just incase you aren't,don't forget to raise the grain.wet the wood,220grit,wet the wood,220grit.
 

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Discussion Starter · #4 ·
If I understood you correctly. I should start by sanding my piece to 320 then apply a sealer to close the pores correct? After I apply a few coats of sealer I should then apply the top-coat. sanding in between every coat when it dries.

Are there any specific sealers that you would recommend? Also, have you tried the lacquer that comes in the aerosol can? I dont have any spray equippment.

A little more detail on the clock... Its going to be roughly 18"X12"X5/4
Cut on a band saw in the shape of England. There arent any moldings or lids just a blank piece of mahogany cut to shape..
 

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If I understood you correctly. I should start by sanding my piece to 320 then apply a sealer to close the pores correct? After I apply a few coats of sealer I should then apply the top-coat. sanding in between every coat when it dries.

Are there any specific sealers that you would recommend? Also, have you tried the lacquer that comes in the aerosol can? I dont have any spray equippment.

A little more detail on the clock... Its going to be roughly 18"X12"X5/4
Cut on a band saw in the shape of England. There arent any moldings or lids just a blank piece of mahogany cut to shape..

If you're spraying from a can, you'll have to get good smooth coats without runs. You can't adjust flow or air pressure, so you're working with technique. Your passes should start before the subject, pass over it and come off the end at the same height so that you get an even coat.

For that preparation, a paste wood filler would save countless coats of trying to fill the grain with sealer and topcoat. Read about filling the grain here.

As for sealers, use a lacquer based sanding sealer under the lacquer. Depending on your last coat, you may still want to "rub out" the finish.




 

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Discussion Starter · #6 ·
Would this work...
Use the sanding sealer first, then tung oil, then the poly top-coat?
The poly says it can be used over oil-based finishes.
 

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Old School
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Would this work...
Use the sanding sealer first, then tung oil, then the poly top-coat?
The poly says it can be used over oil-based finishes.

If you're using oil base polyurethane, the tung oil is unnecessary. You can use just the poly as a sealer. The first coat or two can be thinned 25 - 50%. Then build up coats sanded in between, or start with a sealer (or paste wood filler if you want to get into that much work).




 
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