My optical table and breadboard build..

As I mentioned over in Gas Lasers... I have wanted to do Holography for about 15 years or more... I had build a concrete platform for my setup and then lost interest back in the day... Well, its time to get back to work!

Here is the table as it sits:

Untitled by Christopher Purdy, on Flickr

Its basically right out of the old holography book (can't remember the name atm..) Concrete blocks holding up the table top... but I improvised to get more weight. I used 2'x2'x2" thick paver tiles as a base, and then poured 2" of concrete on top of that as well. Doubled up carpet separates all the layers.

I have been experimenting with DIY optical mounts. I came up with these by visiting the plumbing section of home depot. Basically, its a floor flange with three 1/4X20 holes drilled and tapped for leveling screws. Then a 2" nipple and a 90 degree bend. I then hot glued a DIY FS mirror to that.

This is an interferometer setup using these mounts.

Untitled by Christopher Purdy, on Flickr

The beam splitter is some hand cut plate glass per my other post. I milled a 1/8 inch slot in a cap and hot glued it in there, and then screwed it onto the 2" nipple.

The interferometer shows that it is rock solid... and recovers from a tap in well under a second.

All parts can be fully adjusted... albeit they are a bit sloppier than I would like... which leads me to my next project...

Have a look at this:


Untitled by Christopher Purdy, on Flickr

I procured an 18" X 18" X 1/2" thick aluminum plate from the scrap bin at work today. I have laid out a 1" grid of 1/4X20 holes... I got busy and drilled about 1/3 of them tonight...

The bad news is I will likely be hand tapping them as the thickness of the plate will snap the tap I fear if I chuck it in my drill... which is what I did with my last optical breadboard that was based on 1/4 inch thick plate..

I'll post updates as things progress..

Wow, quite a project- the finished product will be very rewarding, though! Look forward to the updates!

The poor-man's holography setup is usually just putting the apparatus into sand. You might want to place the table's feet into sand too.

Bionic-Badger said:

The poor-man's holography setup is usually just putting the apparatus into sand. You might want to place the table's feet into sand too.

Click to expand...

Yup - I know... and I had planned on that... But one problem..

We have a cat now... and we didn't 15 years ago...

Cats use sand for *other* purposes... And trust me - I know this guy very well, he would LOVE to use my optical table as a giant litter box..

So, no sand..

Escher ---
Taping threads in Al is a trick for sure. I'd go with a low % thread and
I use Kero as a cutting fluid. I don't think you need more than a 50%
thread so a larger drill might work for this.
HMike

Thanks Mike - I've been reading up on it a bit and it looks like I need a two flute spiral point tap used for power tapping... so I'll likely get that... until this morning I had no idea there were so many kinds of taps!

A big thanks to Bowtieguy! He's local to me and we met up for a bit this afternoon and he set me up to get this project done right!

Thanks again!

Hope the goodies work out for you. Work safe, and let me know if you need anything else! :beer:
Keep us up to date as your project moves along.

Escher said:

Yup - I know... and I had planned on that... But one problem..

We have a cat now... and we didn't 15 years ago...

Cats use sand for *other* purposes... And trust me - I know this guy very well, he would LOVE to use my optical table as a giant litter box..

So, no sand..

Click to expand...

You could put some cat repellant near the table. You'll probably want to do that anyway, as I doubt you want the cat disturbing the table itself either.

Also you can just put some screen in the vacant sand areas to prevent access.

Done... Its amazing how much the proper tools help.

Untitled by Christopher Purdy, on Flickr


Untitled by Christopher Purdy, on Flickr

I had planned on anodizing or painting it black, but the brushed aluminum looks quite nice..

Another hearty THANK YOU to everyone, especially Bowtieguy for getting me the tap I needed!

That plate turned out great Chris, glad the tools helped!
Anodizing would look excellent, but if you leave it "natural", you can always renew the surface yourself to keep it lookin new!

A +1 for a nice job! :beer:

Thanks again!! Tonight I will be tackling a kinematic mount prototype design I thought up...