Aluminum Can Tables - what's new?

John Klayer · Post by **John Klayer** » Mon Oct 25, 2004 12:01 pm

I'm still at it. I finished a breadboard last night that has the 1/8 inch pipe sections in the spaces between the cans. I'm letting the JB Weld set for 24 hours with a lot of bricks for pressure. I plan to test it tonight with an interferometer.

Tony · Post by **Tony** » Mon Oct 25, 2004 12:52 pm

It's been a while since a post appeared on this thread. Thought I'd mention that my hexcan table has been working great! Since I worked out the thermal issues, I've had very consistent results. I think a lot of my earlier questions about brightness, especially in reflection holograms, were attributable to table stabilitiy issues.

To summarize:

Laser is thermally isolated from the table, using foam core to block radiated heat from getting into table skin; also foam core divider between laser and rest of table to block thermal air currents.

2x2' hexcan table, 16 gauge steel skins. Four 1x1' patio blocks for mass, 22" bicycle inner tube.

John Klayer · Post by **John Klayer** » Tue Oct 26, 2004 5:09 am

I did the first test of the hexcan breadboard with the pipe sections in the spaces between the cans tonight. I like what I saw. I set up an interferometer on the breadboard and placed it on a desktop with no isolation material of any kind. The desk was setting on a wood floor. I got a rock steady interference pattern that wasn't affected by the traffic on the highway in front of my house or the nearby train. When I stomped on the floor the pattern would jerk and snap right back to steady. I could hold the board in my hands and watch a steady pattern. I think I'll bring it to the PCGG-II.

John Klayer · Post by **John Klayer** » Wed Nov 03, 2004 5:34 am

I did the 10 minute Liti test on this hexcan breadboard with pipes setting on a desk. The test was a one beam transmission. I'll try it with a two beam transmission.

John Klayer · Post by **John Klayer** » Wed Nov 10, 2004 8:02 pm

I did a split beam transmission hologram on the breadboard with no type of isolation, just the pipe/hexcan setting on a wood table with a HeNe on a lab jack next to it. The beam entered a 50/50 beamsplitter half went thru a lens and bending mirror to the PFG plate, the other half bounced off a mirror to hit the back of a white plastic skull to illuminate it to be the object light. It worked. I took some pictures of it that I will try to post tonight. I am taking the hologram to the PCGG with me.

Tony · Post by **Tony** » Wed Nov 10, 2004 8:07 pm

John-

What was:

-exposure time
-laser power
-beam area at film

How bright is it compared to silver?

Sorry I won't be at PCGG 2...

John Klayer · Post by **John Klayer** » Wed Nov 10, 2004 9:35 pm

Tony,

I did 5 and 10 second exposures. The beam was about 2 inches diameter. The laser was 11 mW. It was silver, PFG-01. No it isn't real bright, the beam ratios aren't right and the plate is old. I'm just glad that the breadboard is stiff enough and stable enough to make a hologram, especially since there was no isolation.

John Klayer · Post by **John Klayer** » Thu Nov 11, 2004 12:15 am

This is a picture of the breadboard on a table top. It is more like a cabinet, it was part of my wife's dressing room before I took it over. The HeNe is on a jack and separate from the breadboard. Notice that there is no isolation material between the breadboard and the wood top. The cardboard box is just there to hold the black card shutter in place. The beam enters at the far corner and splits at the 50/50 beamsplitter and half is directed thru a lens, bounced off a mirror and then to the PFG-01 holo plate in the near corner. The other half is bouncing off another mirror then to the back of the white plastic skull near the holo plate.

This is from a different view point:

This is the plastic skull object:

This shows the object beam hitting the back of the skull to light it up:

This is a picture of the resulting hologram. It was not very bright because of the bad beam ratio and the plate is old. The digital camera is very basic. The image looks better to the eye than the camera:

I wasn't trying for beauty, just testing if the hexcan works.

Tony · Post by **Tony** » Thu Nov 11, 2004 1:24 am

oops, I got my threads confused, I thought you were fooling with the litiholo film in this post...

I notice two things from your photos-

-Some of you magnetic bases hang over the unsupported area at the corner where there's no can underneath. This seems like it could be a problem if the skin flexes. I try to avoid that.

-Also, I think even with a hexcan table, you still need isolation from the floor with an inner tube, etc. Even if the table is infinitely stiff and rigid, it will still transmit vibrations to the optical mounts. If they are not infinitely stiff and rigid, they will vibrate.

John Klayer · Post by **John Klayer** » Thu Nov 11, 2004 1:45 am

Tony,

Yes I am quite aware of the gaps along the sides. I've been thinking of ways to fill them in efficiently with different size pipes. This is one of the things I want to talk about at the PCGG.

When I build the bigger table size hexcan, I will have inner tubes under it. Not using any isolation material was just an acid test of the concept.