curve for engranver

[dom ainza]

brand new to this site as well as engraving
just bought a universal 300 that my brother and i are going to start a small business with, we hope

based on what i seen, it seems that we can only engrave on flat items, i have seen some skateboards with a full engrave on it, they said they use some special rotating clamp to get to the curves, what type of clap would that be or how can this be done, i was looking at doing some art work with curves as well
wonder how hard this might be

any help would be great thanks

[Gary Hair]

Dom,
You can engrave curved surfaces without anything special, the limitation is that you only have about 1/8" focal range on your lens and then it's out of focus. If you need to go beyond that then you need to get a rotary attachment for your laser. I have a GCC so I can't say for sure about Universal, but I would bet that the manufacturers website will have info about it. There are bound to be plenty here that have the same laser and can help as well.

Gary

[Mike Null]

Gary

He's looking to engrave a board about 8" wide x 34" long with both ends curved up about an inch and a half. I've seen the boards and would like to do them as well but am unaware of a way it can be done with a standard cabinet type engraver.

[Gary Hair]

Would it be possible to break the engraving up into sections? You could engrave a bit, refocus and engrave some more. Or, could you clamp the wood down flat and engrave? My laser is plenty big enough to handle this job but the 1" curve is pretty tough to get around.

Gary

[Mike Null]

Gary
Here's a web site showing dozens of these all designed by recognized professional designers.

http://www.flickr.com/photos/7259223@N05/sets/72157594580141913/show/

[James Stokes]

Those engravings are very deep. Some of the boards look flat, they do not look like they have any curve to them. Also some look like they were engraved flat then bent to shape.

[Mike Null]

I believe these are actually skateboards so they would bent and laminated before engraving unless the top layer was added after engraving.

[Rodne Gold]

What about doing the designs in veneer or wood grain formica and applying to the pre bent board?

[Mike Mackenzie]

My guess here,

They were done on a high powered laser probably 500 + watts using a 4" focal Len's.

Using this focal lens will allow you to go 1" in or out of focus they may even be using a 7" focus lens which will allow more focal tolerances. With the depth I saw in some of the pics. It has to be a HIGH power laser other wise this would take forever to do even with 120 watts and a 4" lens.

I have seen 1500 watt lasers do this without any issues anyone have an extra 750K to get one?

[dom ainza]

this is what i saw, in the article as i looked it up more from the link above

they used a epilog 36ext laser with 1200 dpi and "Because a laser can only carve on flat surfaces, Ionescu used a rotating clamp that angles the deck during cutting, keeping it perpendicular to the beam to prevent distortion on the curved noses."
this is not to roatry attchment is it?

still new to this so not sure what pwer that has or how it is any differnt from what i have

is there a specal clamp companies make for this?

[Mike Null]

I'm inclined to go with Mike's explanation but I also read about the rotating clamps. I can't visualize raising the ends up by several inches and staying in focus.

With that, you'd have to have a table 36" wide as these boards are 33"-35" in length.

[Dave Jones]

The 36ext mentioned does have a 36 inch wide bed.

Here's a photo from that guy's portfolio showing some of the boards haging on a wall, so you can get an idea of how curved they are.

http://www.redtengu.com/images/raw/skate1.jpg