Help me in finishing the Walnut Plywood

[Raj Shukla]

Hi;

I am a novice trying to finish a CNC cut plywood panel(walnut) which look like the attached pictures.

Experts could you please advice on what could be best way to finish it ? If you doing this, how would you go about it?

I am open to all suggestions but initially that I thought that getting a finish like the one shown in the panel image attached might look good.

Please advice and recommend? As I mentioned i am a novice so any suggestion will be a good one.

TIA

[Jamie Buxton]

Finishing the front (the walnut) is pretty straightforward. The challenge is what to do with the edges -- all of those laminate layers. Most finishing materials -- for instance paint or varnish or lacquer -- form rather thin skins on the surface. By thin I mean a few thousandths of an inch. The edges will telegraph through that thin skin. Perhaps that's okay with you. You might make a sample on a piece of scrap plywood.

[Raj Shukla]

Thanks for the reply.
What are my potential options for the edges? Any advice suggestion ?

[Jamie Buxton]

What’s your budget? Would you be willing to invest 200 man-hours into the finishing task? If not, how much?

[Raj Shukla]

I did not have a budget in mind, this is my own DIY project and would like to make sure it looks good for a reasonable effort. I am not sure what should i be doing?
Hence looking for some guidance from the experts like you. Please advice, if it require too much time i might do it in portions etc.

[Jamie Buxton]

Your plywood has a walnut face. Usually people use hardwood-veneer plywood because they want that walnut wood to be the visible face of the panel. However, your sample panel is all painted. Which effect do you want?

[Raj Shukla]

I was leaning more towards staining so that the walnut wood is visible, this panel will go on area with dark brown(Kona) color, so need to keep it light

[Robert LaPlaca]

Raj, it’s kind of tough to see the scale of the piece, but maybe since you want to show off the Walnut, you might be better served if the panel was cnc’ed from a glue up of solid Walnut. It would make staining a whole lot less challenging..

[Raj Shukla]

Thanks for response.
As a novice that was a mistake I made, would have been better off, if I went with a solid walnut. This is 4 ft by 8 ft in size. I can also look into painting it like in the sample, if it will be very challenging to stain.
Please recommend ?

[Robert LaPlaca]

I am with Jamie here, it’s going to be quite the challenge to treat the plywood core, which is some secondary wood that will not stain the same way a the face veneer of Walnut. So the challenge is how to treat the core, masking off that much detail to treat it differently on a 4x 8’ panel is something I wouldn’t want to do and is going to take a lot of hours.

I have seen hot rod painters use a stick on masking sheet when painting flames on hot rods, the sheet masking is place on the surface, then painstakingly cut with a exacto knife...I think the product was something made by 3M. But once again most hot rod paint jobs are 40-50k paint jobs.

[Jamie Buxton]

One more question...Will you see both faces of this panel? Like maybe you’re using it as a room divider.

[Jim Becker]

Since the panel is already cut, you might consider taking the (extreme) time to paint the cut edges, lightly sand the faces afterward to clean them up (with a block not a soft pad) and then coat the entire piece with varnish or other clear finish that retains some amber properties to highlight the walnut. Walnut generally gets lighter over time with UV exposure and oxidation. Were it me, I'd use a dark paint for the edges, such as black or dark brown (or a darker color like red if you prefer) and then complete as described.

This kind of lattice like project could benefit from laying up your own "blank" to simplify things in the future...glue up a solid panel that will provide the contrast you prefer and then veneer the panel with your choice of wood species. By example, you could use maple for the panel and walnut for the veneer. In that way, you take care of everything in one shot. Of course, you need to be very careful when you machine it on the CNC with regard to cutter choice and tool-path cut parameters to avoid shredding your edges.

[Mel Fulks]

Agree with Jim. Paint. And it will look better than solid walnut. The face is the star.

[Al Launier]

This is a beautiful piece and I don't wonder why you'd like to finish it off proudly. However, I think with the amount of detail involved, the risk of contaminating adjacent surfaces with stain or paint, regardless of what process you use, is very high. Masking will be an everlasting nightmare with all the curves adjacent to the walnut face.

If it were mine I think I might just spray the entire piece with a clear polyurethane to let the contrasting plywood plies speak for themselves. Several light coats of Poly would preserve it well over time. The walnut would be darker, as would the ply joints which I think would look good, plus the naturally pleasing effect of the irregularities present the piece well.

You could then use this as a demo, if you are doing this for income, and then make the client's piece as a layup, as Jim suggested, using whatever wood they want. That would still allow you to "clear coat" the entire piece for the client.

[Bernie Kopfer]

How about spraying it with a waxless shellac. It will show you pretty much what it would look like if you were to use poly.
then if you don't like the look you have the edges undercoated for paint.