Edge finishes and top coats

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Just wanted to see what everyone was doing when the parts come off the machines. I’m mainly working with birch plywood and trying to make things look more professional and clean. I’ve been doing a small chamfer on the parts but of course that is only good for one side.

Currently I give most of the parts a quick hand sand to get the fuzzies off and then either use them as is or put some urethane high gloss on there and then sand with 2,000 grit for a super smooth finish.

I see a lot of YouTubers using the ridgid oscillating edge sander but I don’t see many other manufacturers making them so I feel like it’s more of a gimmick than a tool worth the $250 CAD.

I also just picked up some paste wax so will give that a try soon.

What do you guys think of an oscillating edge sander?

What is your go to finish for plywood parts?

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Oscillating spindle sanders have been around for a long time and so have belt sanders. The combination seems a little extra complicated to me, but I don’t have a good stationary sander anyway.

I have seen them use those a lot when using a bandsaw to just miss the line and finishing with the sander to get precision. But the cnc should be pretty precise already. It would be useful for removing tabs.

You can also use a downcut bit for a better finish on the top.

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Yeah I have not tried a down cut. I’m actually cutting everything with straight flutes these days, both 1/8 and 1/4. Seems to really help save the veneer layer. I’m just seeing some really nice edges, especially on some wooden kids toys that makes me wonder how they are achieved at a hobby level

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Instead of sanding, especially on thin sections, I’ve been putting cut pieces on a board for support and working them over with a tile/grout cleaning brush, works pretty well on the ‘fuzzies’. All I can find in local stores in the line of toothbrushes are rated soft or medium, I’d really like to find one rated ‘bleeding gums’ to try on the fuzzies. Shellacking the surfaces before cutting may also help cut down on the fuzzies and has the advantage of drying quickly.

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I will have to try that. Good tip!

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If you have a router table, you can get sanding drums with a 1/4" shank. That being said, they MUST be used with a speed controller. They are not meant to spin at router speeds. It’s a poor man’s spindle sander… obviously it doesn’t oscillate. I just raise the drum when the paper loses its umph.

I use the cheap-o speed controller. You lose torque at very low speeds, but there is a sweet spot between torque and safety that has been working for me.

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I got myself one of those Rigid oscillating spindle/belt sanders years ago for work. I mostly use it to clean up after bandsaw, scroll saw, and jigsaw work, and occasionally to flush sand an edge joint with thicker veneers. I honestly can’t see it being much of a companion to a Cnc though.

There are otherwise many things you can do the reduce the fuzzies before sanding. First is cut order; cutting contours from the bottom up with an upcut bit reduces fuzz… visa versus cutting top down with a down cut bit is best. Also you can use a wood treatment, which is commonly found at paint stores and wood working places. It is basically a thin shellac or urethane that is meant to soak in and bond the grain. Guys that turn wood like to use it before filling, to make filler bond better. I figure it would certainly help to treat the wood before finish cuts; supposed to make grain woods cut like delrin… sorta. Using a vacuum chamber to treat can get it deeper where you can treat almost the entire thickness.

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Thanks @truglodite, do you feel the ridgid is a good tool to have or not used all that much?

I did pick up some paste wax today and it got some good results with fast and easy application. One of these squares is raw and the other is waxes. It really makes the layers pop

PXL_20210503_032323097.MP
PXL_20210503_032323097.MP3024×4032 2.86 MB
PXL_20210503_032333232.MP
PXL_20210503_032333232.MP3024×4032 2.89 MB

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To be honest I don’t do much work that requires it. So it is far from my most valuable tool purchase. With a Cnc, if you do a lot of tab cuts it may be worth it. Otherwise I would invest elsewhere. My dewalt random orbital sander is by far my most valuable sanding tool, followed by my pc262 belt sander.

I forgot to mention, for finishes along the lines of what you are talking about, you can also try some of the common rub on finishes. Tung oil, boiled linseed oil, and wipe on poly are good cans to have around the shop. All of them are super easy to apply, don’t obscure the grain (makes it pop), and dry to a decent sheen after you build up a few coats. Wipe on poly is the most modern of the 3 I mentioned. Both the poly and BLO finishes can be waxed after cured for a very durable finish. Tung oil is best for non toxic uses… excellent for endgrain cutting boards.

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No personal experience, but this seems close to what you’re looking for:

https://www.precisebits.com/products/miscellaneous/fuzzbrush-tools.asp

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I use one of those on my drill press. It works ok for small jobs.

As for finishes, shellac is my new favorite. It isn’t easy to clean up, but you can just let the brush get crusty and then soak it when you start next time. But it leaves a strong finish, dries quickly. I think I did 3 coats and then sanded with 320grit then a finish coat and I buffed it a little with 0000 steel wool. It literally dries in 15 mins.

Polcrylic is also a good choice. Water clean up, doesn’t stink. It doesn’t have any color to it, so pieces end up a bit lighter in color.

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That polycrylic seems to be awesome, I always hated the cleanup with regular polyurethane, I just bought cheap brushes and tossed them.

This sounds like a better protector than the minwax I picked up

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COOL! New (at least to me) stuff to try on the shelf at Lowes!

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Unlike many woodworkers, I really like putting finishes on projects. Depending on what you’re doing I prefer Deft Spray-on lacquer (recommended by Rob Cosman), Waterlox tung oil finishes (preferred by many woodturners), or Minwax Polyurethane (or Varathane). All these come in gloss or satin finishes.

Lacquer for jewelry boxes, small projects, and items that get occasional use.

Waterlox for durability and keepsakes, because it will truly last a long, long time as it continues to polymerize for weeks after application. Other tung oils with accelerants are also good, like Formby or Tru-oil. You can get wonderful high gloss finishes with it. It really shows off depth in figured wood.

Polyurethane for heavily used surfaces, such as tables, chairs, rocking horses, etc. I have used but now stay away from polycrylic because the water base tends to raise the grain on a perfectly finished project and it tends to not build up as well as regular polyurethane.

I used to use Danish oil, but it never hardened as well as tung oil. Shellac is great if you put in the time for a deep shine (many, many coats) and can be repaired, but a good lacquer is nearly as good. You can also get a very nice catalyzed lacquer at Sherwin Williams for larger projects that is very hardy also (higher end tables). I’ve used epoxy and resin, mostly for fill and the resin polishes for the various brands are usually very nice, but expensive.

I have come to really hate straight wax on wood. It remains soft and keeps you from ever applying another finish. I’ve never understood the appeal and think it’s just a misunderstanding since the wax on top of another finish (like lacquer) is traditional furniture care. But straight wax… shudder.

If you want to spray polyurethane, then thin by about 10%. In fact, thinning by 50% gives “wiping poly” which works nicely for touch-ups. With some thinning polyurethane also brushes and levels very nicely, but you need to wait long enough for recoating.

If you really want a glass-smooth finish, then 2 coats of sanding sealer followed by lacquer is very hard to beat. Think Steinway pianos…

Really, though, try a few things and see what you like…

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Oh, and as for bits for baltic birch plywood, I spent the money on a couple of compression bits that work great. They cut to the center of bit, so upcut on the bottom and downcut on the top so that both top and bottom surfaces come out extremely cleanl with no fuzz or chips. Make sure you do a 20 thou (or so) finishing pass on side cuts. You still have to slightly relieve the edges to soften them up, or you could literally slice your fingers on the wood.

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Fantastic info thanks for your real world feedback. I was stoked on the wax and it left the finish I wanted and was easy to apply…and then it dried and it looks boring and like I never applied it in the first place. Also realized I put it on parts that will get another part glued onto it…so that will be fun. I might try to find some Waterlox I had tried a generic brand spray on lacquer and was not that thrilled. Might have just been a shitty brand though, it was a Canadian Tire special.