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Alfred Hoffmann
01-02-2005, 12:40 PM
I tried to post this yesterday but somehow this message didn't post. I would like a recommendation. I will be starting making some gift boxes for my daughters-in-law for next Christmas. It's never too early. I would like their names or pictures of their kids laser engraved. What is the preferred wood to use for the top?

Alfred Hoffmann

Shaddy Dedmore
01-02-2005, 1:58 PM
I've had good luck with Hard Maple, Pacific Coast Maple (a little redder), and Red Alder. Photo's don't show up well on Walnut for me.

Depending on the photo, I've had some really good stuff show up on the PCMaple, I get it prefinished from the Studio Workshop (http://www.studioworkshop.com/). I'm not sure what finish he uses, but I've been able to run a pic using less power than normal, so part of the photo doesn't get all the way through the finish, which effectively gives you a 3rd color to work with... that make sense? I guess if the finish wasn't very even it might be a problem if you came to depend on it, but I've had fair luck so far...

TIP: use a rectangle and PowerClip to select a portion of the photo that you want to test, then you can run it on a test piece. Move the rect around to get more uses out of the test piece.

This photo actually looks a little darker in person. AThis one was run at 300dpi greyscale (not dithered or photograv'd) on an Epilog 24tt 45W, 100spd and 40-50 power I believe, it's been a while, not more than 60 power for sure. For line art and text, I run 100 spd, 75 power, sometimes making 2 runs to get it nice and dark. Her face is a little grey/white, because there's still some finish on it, makes it stand out better.

http://www.shaddysengraving.com/gallery/albums/userpics/10001/LEWoodPhotoPlaque.jpg

George M. Perzel
01-02-2005, 4:02 PM
Hi Alfred;
I have engraved many photos on various woods and rank them as follows for preference, recognizing that a poor grain pattern on any wood can spoil a photo:
1. Alder
2. Hard maple (east coast rock maple)
3. Cherry
4. Butternut
I've tried many others, both domestic and exotic, and have found nothing else worth mentioning. Here's some samples:

Shaddy Dedmore
01-02-2005, 6:29 PM
How do you get them so dark? Is that just from your laser? Looks great.

Shaddy

Alfred Hoffmann
01-02-2005, 6:46 PM
Thanks for the quick reply. Would it be best not to finish the wood prior to engraving?

Alfred Hoffmann

Shaddy Dedmore
01-02-2005, 8:19 PM
Finishing before is prefered. The smoke and resin from the burning process will stain the surrounding areas, not in a good, interesting way. With it finished, you can wipe it right up (with alcohol, or a 409 cleaner type product).

A pledge product will be OK afterewards to sleal the etched area. If it's going to be inside (as most of things will be) a protective coating isn't necessary. But you can play with putting another coat on afterwards if you want... I leave mine plain.

Jeff DeVore
01-02-2005, 10:59 PM
Shaddy,
I have been getting simular results as George is getting on alder using a 75 watt Epilog Legend EX. Have been using 100% power and 65% speed. And to get them darker and deeper yet have been going over them twice however you lose a little detail by doing them twice. I think the darkness is just a matter of slowing the speed down until you start to lose detail. You actually want to burn the wood but not enough to burn it away if that makes any sense. Also I use PhotoGrav which I believe converts the image into black and white because the grayscale image I send into PhotoGrav doesn't look anything like the image that it processes out the other end. Jeff.

Mike Mackenzie
01-03-2005, 1:20 PM
I agree with the choices of wood to laser photos onto. This is the first step in getting a good quality engraving. The other important step is the process of the photo.

It is necessary to clean up, remove busy background and adjust the photos before lasering them. Don't think that you can just scan and engrave a photo on to any pc. of wood. There is some art to getting them to look good.

When you choose the wood you must look at the entire project, Yes Alder engraves very good but will it be a good choice for the top of a box? I think a pc. of hard maple might be a better choice for the project. Try to choose the clearest tightest grain for your tops the more grain you have the more it will effect the photo.

I would get my wood and laser the photo first to see what will look the best you can always plain off or sand off the image Once you get the proper settings and photo image correct Then start the project you will eliminate any guess work before you spend many hours constructing the boxes and then wondering how the photos will look on the finished product.

Remember the rule of thumb measure twice cut once! this would apply to the lasering work as well.

I have attached a couple of samples of photos done on the Universal laser system. One done on Alder and the other done on P.C. Maple the one on Alder is greyscale and the one on maple was photograved.

We always like to use a finished wood because it cleans off easily after it has been lasered and if it needs to be darkened up just add a little black shoe polish. The shoe polish only goes into the area that has been lasered and cleans off the finished wood easily with alcohol.

Pat Kearney
01-03-2005, 4:52 PM
Been reading this forum now for the last couple of weeks and there is great information here for someone like mysef who is planning to buy a laser in the very near future - thanks to everyone for sharing their laser experiences so openly.

In keeping with the topic I never noticed birch being mentioned. I have a great local supplier who provides great quality kiln dried birch at a very reasonable price. What result will laser engraving birch provide for graphics or pics?

Thanks again and keep up the good work.

Mike Mackenzie
01-03-2005, 4:58 PM
Most light colored woods will laser or cut well the question is do they darken once they have been engraved. We have done work with birch as well as beech they both engrave well.

Pat Kearney
01-03-2005, 5:00 PM
Thank you for the quick response. As per some of your other postings the same applies here I guess. Try some samples first-it's the only way to know for sure.

George M. Perzel
01-04-2005, 1:55 PM
Hi All;
Unfortunately there are no secret formulas for getting consistent results because photo parameters change as well as wood densities. The two pics I provided were done on alder with one pass on a Laserpro Mercury 60 watt unit at 100% power and 55% speed-pretty close to what others have reported. I always use finished wood and prefer lacquered wood to ploy finished but difference is minor. In some cases it also helps to put a light coat of paste wax on the wood prior to lasering-don't wipe it off unti you're done and then carefully with a microcloth-no lint ot strings.
I don't favor the shoe polish trick as it tends to make all engraved areas the same color and you lose the resolution. I always use Photograv-only because it eliminates a lot of trial/error. I have had good results with direct images from Photoshop but you have to play around with the brighness/contrast and curves features to get a good contrast and retain image details.
Hope this helps someone
George M. Perzel

Rodne Gold
01-05-2005, 1:13 AM
In terms of what a laser does , the better the beam quality and the more power the laser has , the WORSE wood engraving becomes. Why is this ? Well using the "correct" settings should actually vaporise the wood with very little heat affected zones . The heat affected zone is what gives the wood its contrast and thus the dark effect. So in effect the lower powered lasers with bigger spot sizes actually give better effects and the higher powered ones with exceptional beam quality need to be "fooled" into burning the wood. In a laser , burning is NOT what you really want for most applications so one has to either defocus the better laser or use a higher DPI/PPI so the spots overlap and thus do burn. The problem with lighter and less dense woods is that they contain little resin so one actually gets even less of a "burn". In terms of consistency of wood , well no 2 planks are gonna be alike so either you take your chances , buy a few cubic ft of from the same tree or do what we do . We use various woods as a substrate and veneer a layer of light wood atop them. This works very well , especially if you use a dark wood as a substrate as this then "frames" the plaque , the veneers allow a LOT of consistency and you can get various effects by either lasering the veneer or actualy combining this with going right thru the veneer "cap" and revealing the darker wood. Apart from which we were finding it very difficult to get larger areas of thin solid wood to make stuff out of. Taking 3-6mm MDF or light DF and veneering one or both sides (depending whether you need the bottom to be the same as the top) allows us to use flat large sheets to both laser and cut consistently as well as allowing a huge choice of EXACTLY what type of wood you want , from walnut burl to rosewood to birds eye maple etc. We always finish the wood before engraving as this allows both colour filling and wiping off of residues. We also often use a paper based vinyl application tape on both finished and unfinished wood as this tend to darken the engraving somewhat , protects the surface and allows selective paint filling without having to mask after the laser has processed and is very easily removed and requires almost no extra power to engrave thru. Photgrav is our program of choice as it almost always gives pretty good results. We also use polyester based Vinyl as a mask if we want really deep engraving into wood as we then sandblast the wood after lasering it to get the depth we need (doesnt work well with photos unless you use extremely fine grit and a pretty gross type half tone pattern so you get BIG dots)
Part of the attraction of laser processing photos and graphics on wood IS the fact that the grain shows.

Kevin Huffman
01-05-2005, 10:34 AM
Hey Guys,
A lot of great info here. One thing I would like to offer is, after engraving wood to get rid of the overburn we use a little bit of Pledge. It works wonders and gets rid of it all.