Any suggestions on how to finish wood parts after laser / CNC? Or any links to quality articles / videos on this topic?
Background:
I’m a complete noob when it comes to woodworking.
But I assume some sort of oil application / surface protection is in order.
Particularly for laser engraving I’m curious to know if different oils give better/worse results when it comes to preserving the quality of the engraving.
I’m also unsure how different oils work with different types of wood; I’m mostly working with birch.
PS:
Please excuse if this has been asked before; a quick search didn’t yield any relevant threads.
What kind of projects are you working on? For instance if you are making coasters a more waterproof finish might be important than if you are making something to hang on the wall, etc.
Good point.
I’m mostly working on “display projects”, so no special need for a waterproof finish.
Nonetheless, also curious to know how a waterproof finish can be achieved, in case that will become relevant.
There are a lot of choices.
Some of it is dependent on whether you need it to be food safe.
Is it for outdoor or indoor use.
I like using wipe on polyurethane for stuff I want to be more waterproof. There’s also a product called Emmet’s Good Stuff that’s great for butcher blocks and counter tops.
For oils mineral oil is food safe and protects well enough.(Good for slate too) Linseed oil gives a beautiful finish. Both you just wipe on and wipe off.
Well there are a ton of options, but every woodworker has a few that they go to.
If you are looking simply to bring out the laser and preserve the wood a poly may be all you need. Wipe on poly is great because it is so simple, just wipe on and dry, but it is oil based so make sure you have the proper supplies for cleanup. It should also be noted that with age an oil based poly will slightly yellow, so your piece will gradually yellow with time if it is a light wood like birch. Water based poly on the other hand behaves the same, it can be cleaned up with soap and water, and it also tends not to yellow.
For things like cutting boards I really like mineral oil and bees wax, there are lot’s of store bought products or you can make your own.
If you need a good hard finish Shellac is really nice as well, and durable. I have not played with this finish as much but have it all ready to go when I get some more wood projects finished.
All of the finishes I listed are discussed in this video:
There are so many options, it really depends on what you want in the end. I am a fan of more natural finishes and wood colors, but there are also some really cool stains out there too. Make sure you look at things like application, dry times, durability, and safety when considering your choices.
I’m sure there is a lot more wisdom on here, so if you find some finishes that you want info on I hope you post again. This could be a really great ongoing discussion.
For a complete beginner I recommend shellac. It’s old and traditional, but its very easy to work with, and importantly, it can be reworked easily if you screw something up. The solvent is alcohol, so non-toxic and readily available. You can get it premixed if you’re using it up fast enough, as it has a relatively short shelf life after mixing. You can also buy it in flake form and mix it as you need it (dissolve, stir, wait, stir, done).
It’s not waterproof, but would be just fine for decorative projects.
All the skills you develop to put on shellac are applicable to modern finishes, which have lots of better properties but are less forgiving in their application.
@Atom I totally agree, I think I am getting a sprayer as we just started some bigger wood projects and I don’t want to try to finish those with a brush Spray on is super convenient.
This was a project I did for a neighbor a few weeks ago:
I used a water based poly spray (like this) to protect it once the paint was fully dry and cured, it also allowed me to coat the live edge lightly without destroying it.
@eh9 Shellac flakes are also great to have as they come in a few colors so you can customize your finish.
This is what I usually get, my local big box hardware store offers it in both outdoor and indoor variants witch is great for when I want to hang a project on my front door
Many thanks for all the great suggestions!
After giving this more thought I’d say my priorities are in descending order:
Having something simple / easy to work with / difficult to mess up; as I’m just getting started with this.
Having a nice, ‘natural’, ‘earthy’ finish of the parts; as mentioned I’m mostly working on pieces to be displayed rather than used.
Having durability and protection; not that critical from my point of view, happy to sacrifice this for the other 2 points; nonetheless, if a solution meets 1) and 2) but also offers some scratch or humidity protection, it would of course be preferable.
One follow-up question on the topic of oil finishes, say linseed or tung oil.
How difficult are these to work with for a noob?
Should I rather go for shellac if I’m not sure what I’m doing?
Cheers!
The oils are just oils, you can’t mess them up period. I have acutely used olive oil to finish and season some of the wood utensils I have carved. The only issue with oils is that they require reapplication to keep the wood looking good.
If you want easy i would do the spray polyurethane. Its as easy to use as spray paint has the same type of clean up as spray paint. It keeps wood looking good for a very long time, and it adds protection against humidity. As a reference polyurethane is what is used to finish hard wood floors in houses. So think about how beautiful wood floors look
In my opinion shellac is best for high weare environments (tables, coasters, etc)
But that is my 2cents as others have said there are a lot of options and people tend to pick there favorite and stick with it.
I agree with @Atom oils are really easy and beautiful, but have more upkeep.
I have oils that I ocassionally use, the key here is looking at product specific information. For example, old school raw linseed oil takes days to properly dry between coats, there are modified linseed oils that take less but expect a few days worth of finishing work if you are using that. Here is a good article: https://ardec.ca/en/blog/22/linseed-oil-a-natural-solution-for-wood-finishing
Vegetable oils will turn rancid over time. @atom, I’m glad you’ve had good luck with that, but for new people just getting started I think there are better finishes. Mineral oil would be better than vegetable oil.
This is why I recommended shellac. It’s about as as simple as a wood finish gets and it’s friendly. Use it to practice basic application skills with a brush, pad, or if you have one, a sprayer. If you screw up, wipe off excess finish with an alcohol-soaked cloth. When you’ve got some experience with this material, then you can transfer your application skills to whatever you choose next.
Now having said that, shellac is not a top-finish that I’d ever use any more. There are some fantastic high-chemistry-tech finishes being made, and I use those. Shellac does retain currency in this world, though, as an undercoat, where it’s an excellent sealer. It can also be used for undercoat tinting.
Shellac, when first collected, is dark brown and then refined for finish uses. Degrees of refinement give rise to a variety of shades, from light brown to orange to yellow to to white, with their own color names like garnet, amber, and blonde, The earthy tones you want are easily available from orange and yellow varieties. It likely what you’ll get anyway if you pick up a small can of premixed finish, but check the label. Zinsser, carried by Home Depot, has products labelled “clear” and “amber”.
More difficult than shellac. Easy to apply, but they can be harder to get looking how you want.
Oils aren’t “just oils”; there’s more to it. The most important distinction is between drying and non-drying oils. Drying oils, which include linseed and tung, will naturally polymerize when exposed to air. Non-drying oils, which include olive oils, do not polymerize and do not solidify. Non-drying oils are typically used for food-contact products such as utensils, bowls, and cutting boards. Drying oils can either be “raw” (unmodified oil from the press) or processed (typically by heat). Drying oils can also be formulated “driers” (metal ions; toxic for ingestion). Both processing and driers decrease the curing time of the finish and often improve its hardness. Read the label and the manufacturer’s spec sheet.
Wood finishing is a large subject. Best to start simple. Proceed as far into its details as your interest takes you.
A beautiful quote that made me smile!
Many thanks for all these suggestions;
I will have a chat with the folks at the local hardware store and see which products they have.
In any case, I have a much better understanding of what’s out there now.
@brent113 yes vegetable oils can go rancid. That is why I only use it on food items that get washed and retreated regularly. The nice think about olive oil is that all olive oil is food safe, not all mineral oil is food safe
@eh9
You make a good point about the variety of oils. I only use wet oils and only for food grade items. In that application they are super easy. Apply oil let soak in, wipe off. Repeat as needed until wood looks “wet” even when dry.
@SabinSnorlax I also reccomend looking to see if there is a local woodworkers supply/hobby shop near you too. The guys at those shops are usually there because they love the craft and like to share the knowledge. l’d love to hear what you find.
Also don’t forget that the esult of any finishing product will hugely depend on the quality and preparation of the surface you apply it onto. Most finishes (especially those that don’t create external layers, like oils) will rather accentuate than mask defaults… So sometimes it’s simply better to leave the wood raw
Anyway, one simple rule: always test and refine your finishing on some scrap or sample piece obtained with a similar process before applying on your real piece. You’ll gain confidence and avoid a lot of disasters!
If I’m trying to figure out what finish to use, sometimes I’ll take a scrap piece and do some side-by-side tests. See how it reacts and what it does to the character of the wood. Testing will save you a lot of time and heartbreak. I had a brand new can of spar varnish that I was going to use on an outdoor swing. I went and did a test just to double check. Something was off and I couldn’t quite tell what. I just chalked it off to being a new brand. (they were out of what I’d previously used) I came back to check 24 hours later and the test hadn’t dried. Not sure what it was, if it was an old can or a bad batch. Found my usual brand at a different store and no problems.
Spray on is super convenient.
