Material thickness when using air assist cone?

[Dan Hintz]

I had one of those "Duh, that should have been obvious" moments a few days ago. Due to my lack of a 50 mil hex wrench, my air assist cone sat unused in the box. I thought it would cut down on the amount of lens cleaning I was doing, so the last time I was at HF I picked up a cheapy set (and boy was it cheap... I used one of the larger ones in an attempt to loosen the ruler screws and broke the wrench in two places :mad:).

So on goes the cone... and then it hit me. My material thickness has suddenly gone to crap! I can only etch items that are flat within a few millimeters... tile, acrylic, etc... but I can't do a simple 1/2"-lipped bowl! Oh, for Pete's sake! Grrrrr, I may be forced to grab a 4" FL lens after all.

Just a rant...

[Bjorn storoien]

Air assist is for cutting and i usually dont cut lipped bowls :)


Bjorn

[Dan Hintz]

Air assist is for cutting and i usually dont cut lipped bowls :)
I came across some nice wooden "bowls" (more like a platter) that I wanted to cut a design out of the middle for wall decorations. Not everything we cut is going to be flat.

BTW, the ULS machines have an air curtain optics screen... I thought it would be nice to funnel this air out of the cone for increased protection against particulate matter, not as an aid in the etching process.

[Scott Shepherd]

Whatever you do, do NOT, repeat NOT run the air unless the cone is on. It WILL (and DOES) create a vacuum and sucks debris onto the lens. It'll crack you lens in a matter of minutes.

[Mike Mackenzie]

Scott,

A slight correction Do not have the cone on without air this will crack the lens. It is perfectly fine to run the air without the cone on. It is very important to have air flow through the cone once it is installed.

Dan,

We use a thumb screw on the air assist cone it is much easier than those DUMB set screws. Thread size is 440. Also you may want to consider just getting the 1.5" air cone It is way cheaper than the 4" len's assembly.

[Scott Shepherd]

Scott,

A slight correction Do not have the cone on without air this will crack the lens. It is perfectly fine to run the air without the cone on. It is very important to have air flow through the cone once it is installed.

Dan,

We use a thumb screw on the air assist cone it is much easier than those DUMB set screws. Thread size is 440. Also you may want to consider just getting the 1.5" air cone It is way cheaper than the 4" len's assembly.

Mike, not on my machine. Leave the lens off and the air on and cut some black rowmark and you're fixing to have a cracked lens in no time. It sucks the air right into the lens.

Also, on the 4-40 screw for that cone, mine was installed so the screw was on the right. I took that off and turned it so the screw comes out the left. Made life somewhat easier.

[Bjorn storoien]

ok Dan now im with you

i have the machine as you guys ULS 4,75

and moving the screw to the left side is pretty smart :) i ll try to remeber to do that

Bjorn

[Mike Mackenzie]

Scott,

Assuming that you have STD air assist, You should just close off the valve and then you should have no problems running the air with out the cone. The adjustment valve only controls the air flow to the cone. If too much air pressure is there then yes the air will spatter the debris. Try turning it off or just turn it down and that issue will not happen.

The only other possibility would be that there is a leak in the airline somewhere.