Finishing for a flat surface

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martin54
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Finishing for a flat surface

Post by martin54 »

I know this isn't software related but there are some real expert woodworkers on the forum so for me the best place to ask :lol: :lol:

I have a job to do which has some small text but I would like the surface to be flat so the text needs to be filled, There is to much & it is to small for an inlay & probably to big for paint to give a flush surface without being to thick, thinking my best option would be either wood filler or wax but wondering which might be best & if there is another option.

Just to add, I can't machine the piece after I have carried out this fill, the main part will be stained so I will also be limited in how much I can sand after applying whatever I use to fill the letters.

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FixitMike
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Re: Finishing for a flat surface

Post by FixitMike »

My vote is for wood filler. Much more durable than wax.
After staining and before carving the text, apply several coats of clear finish. This will make it easier to remove excess filler after it is applied.
You can clean up the filler after applying it if the job is left on the CNC and the same tool and setting are used that you used to flatten the piece in the first piece. Maybe raise the Z0 by .002" or so. I'm not clear on why this can't be done.
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martin54
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Re: Finishing for a flat surface

Post by martin54 »

FixitMike wrote:
Mon Aug 01, 2022 4:43 pm
My vote is for wood filler. Much more durable than wax.
After staining and before carving the text, apply several coats of clear finish. This will make it easier to remove excess filler after it is applied.
You can clean up the filler after applying it if the job is left on the CNC and the same tool and setting are used that you used to flatten the piece in the first piece. Maybe raise the Z0 by .002" or so. I'm not clear on why this can't be done.
To be honest Mike it probably could be done but I was worried about the stain, as wood moves so much I didn't want to risk removing parts of the stain, using the same bit would require using a V bit to clean up which would take hours & although my z zero setting is pretty good changing bits still leaves the risk of that happening :lol: :lol:
I have already applied the stain & given it a few coats of clear finish so that part is done :lol: :lol:
Thought that might help if I did have to do a spot of sanding, I experimented using a mask before the engraving but when I removed the mask the wood filler was raised above the surface by the thickness of the film so that didn't work so well :oops: :oops:

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Re: Finishing for a flat surface

Post by SteveNelson46 »

The best option would be epoxy but, if you can't use power tools like a random orbit sander to finish the surface sanding you'll be stuck with plain old elbow grease (hand sanding). That might tale a while. I have some small sanding disks for a hand drill or air sander that are about 1.5" in diameter that I sometimes use for sanding on lathe projects. That might work also.
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Re: Finishing for a flat surface

Post by SteveNelson46 »

To add more to my previous post, I bought the assortment of sanding disks and mandril from WoodTurners Wonders.

https://woodturnerswonders.com/
Steve

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martin54
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Re: Finishing for a flat surface

Post by martin54 »

SteveNelson46 wrote:
Mon Aug 01, 2022 8:21 pm
The best option would be epoxy but, if you can't use power tools like a random orbit sander to finish the surface sanding you'll be stuck with plain old elbow grease (hand sanding). That might tale a while. I have some small sanding disks for a hand drill or air sander that are about 1.5" in diameter that I sometimes use for sanding on lathe projects. That might work also.
I do epoxy fills already but the problem (as I see it) with this is that I can't do a lot of sanding as I risk removing some of the stain although I will admit that I am just guessing with that as I haven't really used any form of stain before :lol: :lol:

I have no real idea how deep they penetrate when applied, using a Colron wood dye on Scottish Oak, I didn't really want to use a wood dye but they want a deeper colour than I can get the Oak in so it seemed to be the only option :lol:

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Re: Finishing for a flat surface

Post by wilkigr »

I appreciate that, for this project, my process will not work. Maybe next time.

I have done vcarves in cherry and maple, filled the carve with epoxy, then sanded the piece flat again. THEN, I have used aniline dye to "stain" the wood. The dye does not adhere to the epoxy, so it is easy to wipe it off.

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Re: Finishing for a flat surface

Post by martin54 »

wilkigr wrote:
Mon Aug 01, 2022 9:26 pm
I appreciate that, for this project, my process will not work. Maybe next time.

I have done vcarves in cherry and maple, filled the carve with epoxy, then sanded the piece flat again. THEN, I have used aniline dye to "stain" the wood. The dye does not adhere to the epoxy, so it is easy to wipe it off.
Now if I had known that then I doubt I would have this problem, maybe I should have asked the question before I started the project :oops:

Bit late to start again now unfortunately but definitely something I will think about if something comes along in the future :lol: :lol: :lol:

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Re: Finishing for a flat surface

Post by Charlie_l »

Another idea.

Use a charcoal stick to get charcoal dust in the text. I just go a little crazy scribbling over the text area. Just a little dust is needed inside to darken the text. Wipe or sand off the surface dust. In my case I then spray some finish like poly to hold the dust inside the text.

May not work for you. I find it works on tiny text.
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martin54
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Re: Finishing for a flat surface

Post by martin54 »

Charlie_l wrote:
Tue Aug 02, 2022 4:10 am
Another idea.

Use a charcoal stick to get charcoal dust in the text. I just go a little crazy scribbling over the text area. Just a little dust is needed inside to darken the text. Wipe or sand off the surface dust. In my case I then spray some finish like poly to hold the dust inside the text.

May not work for you. I find it works on tiny text.
Not come across this before, not got the time with this project but will definitely look to experiment a bit in the future :lol: :lol: I have done something along the same lines using very fine sawdust & then a drip or two of superglue to make sure it is bonded, never thought about just a clear coat to keep it in place. Problem with the way I have done it in the past with sawdust is that the text can end up a little raised & needs a bit of sanding to make sure it is all flush :lol:

As each project seems to be a little different it's good to have as many different techniques as possible :lol: :lol: :lol:

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martin54
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Re: Finishing for a flat surface

Post by martin54 »

wilkigr wrote:
Mon Aug 01, 2022 9:26 pm
I appreciate that, for this project, my process will not work. Maybe next time.

I have done vcarves in cherry and maple, filled the carve with epoxy, then sanded the piece flat again. THEN, I have used aniline dye to "stain" the wood. The dye does not adhere to the epoxy, so it is easy to wipe it off.
OK not got round to experimenting yet but I am guessing that you do not seal the wood at all before the epoxy pour. I have always applied a coat of sanding sealer before doing any work with epoxy but thinking out loud this is going to affect the stain I would think so that isn't going to work for this situation :lol: :lol: :lol:

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Re: Finishing for a flat surface

Post by wilkigr »

Sorry for the delay in replying, Martin.

To seal or not to seal; that is the question. I've played with these projects both ways. It really depends on the type of stain being used. I prefer to do the carve, seal with either a de-waxed shellac or a lacquer sanding sealer, pour the epoxy, sand it flat, then stain. This prevents any bleeding of the epoxy. This process seems to work fairly well, since the sanding removes the sealer from the surface of the material.
However, this is where the kind of stain comes in. If the stain is a penetrating stain, clearly the sealer will at least limit the penetration. On woods like maple, this is not bad, since maple (and birch) can blotch when staining. The sealer helps eliminate this. On other woods, though, the sealer may prevent enough stain penetration to give bad results.
For surface stains, this is not an issue at all. Gel stains, for example seem to do very well with the carve-seal-sand-stain process.

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Re: Finishing for a flat surface

Post by martin54 »

Thanks, something else to add to my long list of things to experiment with at some time should I live long enough :lol: :lol: :lol: :lol: :lol:

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