"Terry" wrote in message
...
On Thu, 24 Feb 2011 01:07:37 -0500, "Ed Huntress"
wrote:

I don't know if this is a factor, but keep in mind that breaking cell
walls
in food products opens up a path for bacteria to get a grip. The
marking
with a laser is the result of burning. Even a tiny amount may invite
bacterial attack. Once they get a colony going, they can attack cells
that
are still intact. Rotten apples in barrels, and all of that.

Or it may be that skin cells alone don't lead to this problem. It's
something that you might be able to research in the technical
literature.

Mark them when they're green, then put them back in the tree to finish
ripening.

LOL! But how do you stick them back on the tree?

I think this was answered earlier in the thread. Super Glue. Just
gotta get the right kind... ;-)
--
Best -- Terry

My grandfather, who owned a tree nursery and was a specialist in grafting
multi-species novelty apple trees, would roll over in his grave. g

I learned to slip-graft apple trees by the time I was six, usually on a crab
apple stock. And to wring and pluck chickens by seven. d8-)

--
Ed Huntress

"Pete C." wrote:

Rich Grise wrote:

Pete C. wrote:
Rich Grise wrote:
Pete C. wrote:
Karl Townsend wrote:

I built ten little SS apple labeling units a few years ago. The
last unit polishing took maybe 20% of the time that unit one did.

When are you going to start laser marking the apples and eliminate all
the little stickers?

Do you mean burn the mark into the apple itself?

Exactly. I know they have been testing the process, not sure how much
progress it's made to commercial implementation.

Well, I'm no greenie or anything like that - I buy day-old bananas because
they're about 1/2 off, and that sort of thing[1], but envisioning apples
with burn marks on them (a brandin' ahrn springs to mind) kinda gives me
pause - like, how well did the wound get cauterized? Breaking anything's
skin is essentially ringing the dinner bell for hungry wild microbes. And
when apple flesh is exposed to air, it starts reacting - when I'm going to
use the apple, how much of it under the burn mark do I have to throw away?

The laser certainly cauterizes just fine, that's why it's used on human
surgery. The depth that the laser burns to is also easily controlled, so
it only affects the surface, not all the way through the exterior.

Patent 5660747 from 1997 seems to be relevant.

"tnik" wrote in message
...
Hey guys, maybe you can help me out a bit here..

Here's the situation. We do some work for the food industry, so almost
everything we weld for them we need to grind smooth and polish the welds
and surfaces. Now this can be on an OD, or ID, or flat area.. Sometimes
its as big as 5" ID, or as small as 2" ID.. At the moment, and this is a
rough estimate, but we'll spend about an hour welding something, and 3
hours polishing. We grind with stones and flap wheels or sandpaper discs
on a pneumatic right angle or straight grinder, then polish with finer
flaps and or scotch bright wheels.

I really have to explore different avenues because this polishing time is
killing us. So, I come to you to ask, how the hell can I make these jobs
profitable?

Thanks for any insight


Tom

Take the resulting work to a finishing (plating) house and have it electro
polished.

Harold

On 02/23/2011 10:07 PM, Ed Huntress wrote:
"Tim wrote in message
...
On 02/23/2011 01:52 PM, Ed Huntress wrote:
"Spehro wrote in message
...
On Wed, 23 Feb 2011 15:02:13 -0600, Karl Townsend
wrote:


The laser marking is supposed to be the solution to all those little
stickers. It's not my idea, they've been testing the technology
already,
I've seen news reports on it.

I've marked a few of the very best Jazz apples with a company logo
using my wee CO2 laser. Went over very well with the founder.

KEWL, I've not seen this but i want one. How much will it cost me to
build a couple units?

The water cooled laser tube, power supply and optics maybe $1K (?) and
you need to scan it. Maybe galvo mirrors or a mirror on x-y. Under 2K
each, I should think.

I don't know if this is a factor, but keep in mind that breaking cell
walls
in food products opens up a path for bacteria to get a grip. The marking
with a laser is the result of burning. Even a tiny amount may invite
bacterial attack. Once they get a colony going, they can attack cells
that
are still intact. Rotten apples in barrels, and all of that.

Or it may be that skin cells alone don't lead to this problem. It's
something that you might be able to research in the technical literature.

Mark them when they're green, then put them back in the tree to finish
ripening.

LOL! But how do you stick them back on the tree?

That's definitely out-of-the-box thinking, Tim. I offer my applause.g

Surely Loctite has something -- don't they have a glue for anything?

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" was written for you.
See details at http://www.wescottdesign.com/actfes/actfes.html