Jigsaw Puzzles


#1

This may well have been discussed elsewhere, as it should have been tried with existing laser cutters. When Baltic birch plywood is cut, there is a little flame at the point of cutting, and the pieces have an attractive ‘grill seared’ edge.
If cutting a picture pasted to the wood, it will be desirable to protect the edge. This might be done by temporarily adhering another material on the picture, more paper, mylar , or what? If access can be made available to the air hose I could see investing in a cylinder of nitrogen to suppress the flame.


#2

At the speed the head moves and the amount of fresh air coming into the unit for cooling, you would have to use a lot of purge gas. Using a “cover-up” sheet seems to be the best option. Frisket film will be one of the first things I test.


#3

What about having the image face-down and cutting from the back?
Would that save the image from burns?


#4

The bottom side of your cut is also exposed to smoke and grime. If you don’t clean the honeycomb or whatever mesh it is laying on top of, it can actually be that your bottom gets dirtiest.


#5

Blue painters’ tape is the easiest, most widely available protective solution.


#6

You can get the blue painters tape, or other colors and brands, in different levels of stickiness so you might want to go with the least sticky option.


#7

My intent was to cut puzzles out on a cardboard/paper stock and I was assuming that the speed you’d travel would be fast enough to prevent most of the marking.


#8

Thinking more about the original idea of a nitrogen(or any non oxygen) flush, it could be a very small flow if routed to a nozzle just to one side of the laser head. There would need to be a way of sneaking in the tube to supply it, which could be quite small. This may be useful if much more sensitive materials are being cut.


#9

[quote=“cassonh, post:8, topic:979”]
or any non oxygen
[/quote] I think the word you’re looking for is inert gas. “non oxygen” is kind of open, as they learned the hard way in 1937.


#10

Nitrogen assist would greatly reduce or eliminate any charring…


#11

Yes,dlaituri, that was what I hoped. Some welding is done in an atmosphere of Argon for a similar reason.
The reason I said “non oxygen” is that to my mind inert gas implies a limited number of elements, and it is possible that any gas which does not support combustion and is cheap and available, such as perhaps CO2 might do it.


#12

Correct, In MIG Orbital Welding we use Ar as a “shielding gas”, but most of the time on non-High Purity work, we like to have a mix of Ar + He as it helps with penetration. So, if we are doing High Purity welding, then we must stick with Ar 99.999% Ultra High.
Also correct, Ar + CO2 is one of the blends used in MIG as the CO2 helps with penetration.

Ya might want to look up how Charcoal is made. Simply removing the oxygen will not stop any charring. It will only stop it from catching on fire. Trust me on this, I did the test and it stunk up my shop for days.


#13

Good point, Spike, like so many of my inventions this may turn out to be a non starter.


#14

Fun fact: I worked at the location for nearly a decade. The ship is plastered on everything. I still blame the Rocketeer for it going down.