I need a laser without a bottom to engrave large items

[Chester Lindgren]

I'm in search of a laser that doesn't have a bottom so I can engrave large, heavy items. Specifically 80 maple stumps with a diameter around 20"-24" with an engraving area of 13"x3". The stumps range from 18"-24" tall.
I used a friend's Full Spectrum Hobby laser to do the sample but there is no way I would ever buy one of those machines....frustrating to use to say the least.
I know Vytek makes some large lasers for engraving gravestones but this project doesn't have the budget to warrant buying one of those machines.

Any other options out there?

I've found these possibilities:
http://www.cnc-warehouse.com/cncwl-4024.html
http://www.checkmatelasers.com/equipment/CheckMate-Lasers-XM8-Series-Bishop2.cfm

Any help or suggestions would be greatly appreciated!

Could a galvo on some kind of gantry work for this? Could be fairly difficult to line up each section though...

[Bert Kemp]

Are all the stumps going to be the same. Would a branding iron do the job?



I'm in search of a laser that doesn't have a bottom so I can engrave large, heavy items. Specifically 80 maple stumps with a diameter around 20"-24" with an engraving area of 13"x3". The stumps range from 18"-24" tall.
I used a friend's Full Spectrum Hobby laser to do the sample but there is no way I would ever buy one of those machines....frustrating to use to say the least.
I know Vytek makes some large lasers for engraving gravestones but this project doesn't have the budget to warrant buying one of those machines.

Any other options out there?

I've found these possibilities:
http://www.cnc-warehouse.com/cncwl-4024.html
http://www.checkmatelasers.com/equipment/CheckMate-Lasers-XM8-Series-Bishop2.cfm

Any help or suggestions would be greatly appreciated!

Could a galvo on some kind of gantry work for this? Could be fairly difficult to line up each section though...

[Keith Winter]

Not that I'd advise this as you would take away the ability of the laser to contain a fire. But I have seen a shop that cut a hole in the bottom of an old used universal laser to fit tall objects. I think they just used a cheap scissor table lift below it to raise and lower items after that.

[Jerome Stanek]

Does it need to be a laser. Shopbot has a cnc unit called the Handibot that would do that

[Mark Sipes]

I'm looking at my Trotec. The ability to cut an access panel in the bottom and still maintain the use of the adjustable table ( remove for stump engraving) and place a hydraulic lift for the stumps under the machine is more than feasible.......



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[Matt McCoy]

What was frustrating about using the FSL?

[gary l roberts]

AP LASER makes just such a unit. Check'em out.

[Kev Williams]

My Triumph has a stationary table, and the box walls below the table are tapered rather than straight. The bottom ends with a catch-drawer, which is about 18 x 12 inches. The way the drawer is made, I was able to cut out the bottom below the drawer, and still keep the drawer in place...


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Here I'm doing a 24" tall x about 6x16" thanks to the hole...
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The machine will accomodate up to 38" as it is. So far I all I've had to do is these boxes, but I get a few every month or so, different sizes but none that won't fit! (so far...)

There IS one big issue with engraving like this: the part you're engraving and the machine are 'divorced'... I wedge my parts as shown and this works, BUT- if the machine starts rocking side to side due to laser head movement, the box WON'T FOLLOW! The box will move because it's wedged, but it can't move in unison with the machine. So before I engrave anything I have to run a full test pass to make sure I have the speed set so the machine won't move.

Still, this beats doing these boxes on a pantograph! ;)

[David Somers]

My Chinese laser can take a 32 inch tall object in it if I remove the table and the table frame. Relatively easy to do. mine is a 900x600 bed, roughly 2ft deep by 3ft wide. You can get this in whatever bed size you want though.

I have the same question as everyone else though. Do you actually need a laser for this? Or would a CNC work. The suggest of using the Shopbot Handibot might fit your need without nearly having the expense of a laser. Anyway you could use a simple router with a template and a bushing on the router plate?

Dave

[Rodne Gold]

Buy a 60/80w laser from China ..$3-4k or so and butcher it.

[Bill George]

My 6 watt open frame blue light diode laser would do it, slow but less than $1,000. Right now I am in the middle of revamping the control system to a Arduino UNO with a GShield V5 to drive the existing stepper motors. The Chinese software was very limiting and Norton's found a virus so all that got dumped.

[Chester Lindgren]

Are all the stumps going to be the same. Would a branding iron do the job?

Excellent idea, but the client is set on laser engraving.

[Chester Lindgren]

It needs to be laser engraved. Mostly because that is what the client wants and secondly because there is a lot of small text.

[Chester Lindgren]

Buy a 60/80w laser from China ..$3-4k or so and butcher it.

This seems to be the route we're gonna take. Either a China or a used machine and then going to town with the reciprocating saw!

[David Somers]

Chester, Depending on the Chinese company you work with, they may either have a model with the Deep Z height you need, or can modify a machine for that Z depth at little cost to you. Not that a Recip Saw is not a good option as well. My main thought is that if you reach a point with the machine and you want to sell it, it may sell more easily if it has not been wacked to modify it, but instead has a clean modification to it. Just a thought. Plus having them do it saves you some time.

Good luck with this!! Interesting project.

Dave

[Bert Kemp]

Laser engraving is just branding the wood with a machine. I don't get the "HAS to be laser engraved" for a few hundred dollars vs thousands you could get a custom Iron made and no one would be the wiser.



Excellent idea, but the client is set on laser engraving.

[Glen Monaghan]

Laser engraving is just branding the wood with a machine. I don't get the "HAS to be laser engraved" for a few hundred dollars vs thousands you could get a custom Iron made and no one would be the wiser.

Branding on wood looks nothing like laser engraved wood... Often, branding is uneven in depth, usually not nearly as crisp as lasering, and frequently exhibits charring in a way that lasering does not because the laser gets depth by vaporizing the wood where the brand burns it. Brands tend to be limited in size and fairly simple, where lasering can be large and complex.

[Bert Kemp]

A custom made branding iron, heated to the proper temp and applied with a press, can give you results that would be difficult to tell it wasn't engraved.


Branding on wood looks nothing like laser engraved wood... Often, branding is uneven in depth, usually not nearly as crisp as lasering, and frequently exhibits charring in a way that lasering does not because the laser gets depth by vaporizing the wood where the brand burns it. Brands tend to be limited in size and fairly simple, where lasering can be large and complex.

[David Somers]

Chester,

One last thought for you. Be super careful if you are using a laser without a bottom! If you inadvertently fired it off without a suitable material in it you could end up boring a hole clear through to China before you caught your error! I can only imagine the horrible international consequences of such an act. Or worse yet, if your laser weren't level and you angled the hole you could pop out into an ocean or a really deep lake, and then all that water would come pouring out onto your side. Probably affect the wobble of the planet, global humidity, the Asian Monsoon season, etc. Please take suitable precautions OK??

Sorry....it just took me 3 hours to drive 40 miles from Everett, WA to our house in West Seattle. I am toast!! And please......don't hit me with that old joke where I talk about how long it took to go 40 miles and you tell me you understand cause you used to have a truck like that too! <grin>


Dave

[Bert Kemp]

Dave sounds like you could do it a lot faster on a Bike and not the pedal type:D. Bikers can use the HOV lane Huge difference in rush hr traffic. If there's a wreck and traffics at a dead stop I scoot down the breakdown lane.
Were not suppose to but do they really expect bikers to sit in the burning sun at 110+it could kill us pretty quick:o



Chester,

One last thought for you. Be super careful if you are using a laser without a bottom! If you inadvertently fired it off without a suitable material in it you could end up boring a hole clear through to China before you caught your error! I can only imagine the horrible international consequences of such an act. Or worse yet, if your laser weren't level and you angled the hole you could pop out into an ocean or a really deep lake, and then all that water would come pouring out onto your side. Probably affect the wobble of the planet, global humidity, the Asian Monsoon season, etc. Please take suitable precautions OK??

Sorry....it just took me 3 hours to drive 40 miles from Everett, WA to our house in West Seattle. I am toast!! And please......don't hit me with that old joke where I talk about how long it took to go 40 miles and you tell me you understand cause you used to have a truck like that too! <grin>


Dave

[David Somers]

Oh Bert. 40 miles in 3 hours? I could do that on a bicycle in waaaaay less time than that. Heck with an engine! Holy cow! I do love Seattle, but our wise city fathers need to have their noses rubbed in the merde they are creating with growth and traffic and construction.

On the other hand....I got to listen to a bunch of radio programs I love, and some podcasts on my phone. And in the long stops I did a bit of sketching while I sat with the engine off. Amazing.

Oooooh! What would happen if......I mounted my laser on the hood of the car facing forward? I would have to buy a fiber laser to get through the steel of the cars in front of me. But if I boost the power could I clear the road in front of me as I go????? Oooooooooh! Bet the courts would look askance at that though. Curses! Another brilliant idea down the tubes.

[Rodne Gold]

I was thinking of mounting a laser source on my balcony to lop off my neighbours overgrowing vegetation that is partially blocking my view...crew cut for the win...

[Klaus Madsen]

I have just bought a RedSail M900 100W.
It has a motorized Z-Axis and it can go down to 400mm.
I know it's not enough but it is nearly there :)

[Robin Powlus]

What was frustrating with the Full Spectrum Hobby laser? I have been happy with mine, but have not done engraving with the bottom removed.