Vecor Burn marks on wood

[Brie -Anne Bryan]

Hi Everyone and Merry Christmas to all!

Just wondering....my boss wants me to vector some hockey stick keychains out of 1/4" solid poplar.....the only problem is that my edges get charred....I have tried many many different settings with no success. This is my first forray into wood and any ideas would be greatly appreciated.

Thanks!

[Dan Ashlin]

You could use a mask to protect the top from smoke residue, but as far as the edges are concerned, the burning is part of the process. I suppose you could give them a light sanding with 400 or 600 grit paper.

[Larry Bratton]

I believe that edges on vector cuts are going to be naturally charred to a certain degree. After all, you are using a burning process to cut the wood. Your quality will be better with proper speed and power settings. Wood does pretty well with low frequencies..500 or so. You might try cutting your wood with multiple passes using lower power settings. Color mapping can be helpful for this process also. However, I don't think you will ever eliminate having a dark edge regardless of what you do.

[Brie -Anne Bryan]

Do you think wetting the wood would improve my results at all?

[Lee DeRaud]

I was told that the solution (useless for me but applicable to higher-power machines like yours) is to keep the beam on any one spot for the shortest time possible: the idea is you want full power and the highest speed that just barely cuts through. In addition I'd run the frequency down even lower, maybe 250-300.

[Michael Kowalczyk]

DO NOT RUN YOUR TROTEC LASER LOWER THAN 1000 hz or you may burn up your power supply. The newer Job control software does not allow the setting to be under 1000 but just wanted to make sure if anyone with a Trotec running an older version, like 7.49, of Job Control, was aware. I was told this straight from Tech support. Not sure if other laser manufactures have a built in protection.

Poplar is not as good a choice as cherry, basswood, or maple because it usually has a higher moisture content and is very fibrous. 60 watts should be plenty of power to go through 1/4" with out charring the edges.

[Larry Bratton]

Do you think wetting the wood would improve my results at all?

I doubt it. As someone else suggested, a different wood might give you better results also. Maple would be a good choice.

[Lee DeRaud]

DO NOT RUN YOUR TROTEC LASER LOWER THAN 1000 hz or you may burn up your power supply. The newer Job control software does not allow the setting to be under 1000 but just wanted to make sure if anyone with a Trotec running an older version, like 7.49, of Job Control, was aware. I was told this straight from Tech support. Not sure if other laser manufactures have a built in protection.

I'm guessing the "1000Hz" you speak of is pulses per second: the frequencies being suggested in this thread are pulses per inch. But at the speeds normally used to vector-cut wood, my ULS routinely runs below 1ips, which means it spends most of its life at well under 1000 pulses per second. In any case, we're apparently talking apples and oranges.

[Michael Kowalczyk]

I'm guessing the "1000Hz" you speak of is pulses per second: the frequencies being suggested in this thread are pulses per inch. But at the speeds normally used to vector-cut wood, my ULS routinely runs below 1ips, which means it spends most of its life at well under 1000 pulses per second. In any case, we're apparently talking apples and oranges.

Lee,
No I am not referring to PPI. PPI for me is when rastering. Hertz is for vector marking or cutting, well at least on a Trotec. Here is a sample settings window to show you.

[Frank Corker]

Brie -Anne Bryan - most definitely has to be the frequency. It should only be 500 max, 5000 which you would use for acrylic would be fine, but when used on wood it will char the life out of it. I have a 45w Helix and it would be able to cope with it.

[Anthony Welch]

All woods I have done vector cutting have some degree of charring. The thicker it is, the heavier the charring. I always use raw/unfinished wood when I cut. I sand the flat sides, stain if neccessary, then spray Deft laquer to seal the whole item, edges included.

[Dmitriy Kumets]

I would suggest cleaning the charred edges.
If you have the time to wash and dry the wood, use murphy's oil soap, a scrubber sponge and warm water.

If you are worried about the water, get gojo or fast orange hand soap. If it's a small job I get the gojo wipes. The orange oil in those products does an amazing job of removing the soot and char

[Dee Gallo]

When I overdo it on wood, I clean the edges by wiping with alcohol. They are still darker than raw wood, but they are clean and smooth and don't leave soot on your fingers. I kind of like the look of the dark edges, gives them a more finished look.

dee

[Mike Mackenzie]

You can also enhance the edges what I did with this 1" poplar sign was to clean the edges real good and then take a rag with a dark stain and wipe them then applied clear coat and the edges are nice and dark which gives a good look to the piece.


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