Fringe Lockers and Stability

[Jem]

Ahhh... So, drilling the holes would be a good idea then?

Unfortunately, I'm stuck with what I've got and am having to make the best of it I can.

I would love to have a proper lab but sadly it isn't going to happen

I'll look into the feasibility of what can be done to improve matters at the weekend.

Jem

[Tom B.]

You could try to find the source of the vibrations - maybe correlate them with house activity, air conditioning, local traffic etc. and time your shoots to take place during quiet periods.

[jnhong]

When the laser and the recording setup are decoupled, as in your case, would slight movement affect hologram recording? Would the interferometer observations indicate that decoupling as the problem? Since you are in a wooden shed, outside noises are likely to affect your laser to table geometry. Is it possible to bolt down the laser and the table together on a thick wooden beam or plank? Bolt them down tight so they won't budge relative to each other.

Joe

[Jem]

When the laser and the recording setup are decoupled, as in your case, would slight movement affect hologram recording? Would the interferometer observations indicate that decoupling as the problem? Since you are in a wooden shed, outside noises are likely to affect your laser to table geometry. Is it possible to bolt down the laser and the table together on a thick wooden beam or plank? Bolt them down tight so they won't budge relative to each other.

Joe

Hi Joe

Thanks for your suggestions. The laser and table are decoupled due to the fact that the laser I am using is a Coherent 532-200, this laser has a fan inside it for cooling. If I mounted this on the table that would cause me even more problems. Having the laser off the table with the fan running causes no interference on the table at all. the small vibrations are coming from other sources. I have no problem with alignment due to the laser being off the table

I am now looking at a way of mounting through the floor on to the very thick concrete base.

Cheers

Jem

[dave battin]

Can you inject an expanding foam or concrete slurry under the floorboards (near feet)to in effect make direct contact with concrete ?

Or temporarly support the table remove the exsisting legs and cut holes in floor, either fill with concrete or now drop feet direct to concrete subfloor ............it sounds so simple! :wall:

[Jem]

Yes, i'm looking into the feasibility of drilling some 4" or 5" diameter holes into the floor of the shed. I was then going to get some large plastic drainpipe (around 6" long) and put it through the holes, I then thought of filling these with concrete. That would give me a sound 'footing' on which to mount the legs and subsequently my table. I just need to figure out how to move everything around so I can accomodate this :think:

I'm definately going to have to do something though, as I don't feel I can progress until i've sorted out this stability issue.

Once again guys, thanks for all your suggestions and help

Cheers

Jem

[Joe Farina]

Yes, i'm looking into the feasibility of drilling some 4" or 5" diameter holes into the floor of the shed. I was then going to get some large plastic drainpipe (around 6" long) and put it through the holes, I then thought of filling these with concrete. That would give me a sound 'footing' on which to mount the legs and subsequently my table.

I don't know if you were planning on this already, but I would strongly suggest not having any part of your wood floor touching the legs of your table. In and of itself, well-dried wood can be quite strong and stable, but a wood floor in a shed is another matter entirely. If there are any gaps in those areas (near your concrete "footings") which might allow air currents to gain entry to the table area, maybe you could add some type of insulation in those areas, maybe some fiberglass insulation for example.

Wood floors usually consist of long planks, and any disturbance along the plank could telegraph to the the table legs. In addition, since the floor is probably connected to the frame of the shed, disturbances to the exterior of the shed could also telegraph to the floor and then to the table. I think.

[salvee]

Yes, i'm looking into the feasibility of drilling some 4" or 5" diameter holes into the floor of the shed. I was then going to get some large plastic drainpipe (around 6" long) and put it through the holes, I then thought of filling these with concrete. That would give me a sound 'footing' on which to mount the legs and subsequently my table. I just need to figure out how to move everything around so I can accomodate this :think:

I'm definately going to have to do something though, as I don't feel I can progress until i've sorted out this stability issue.

Once again guys, thanks for all your suggestions and help

Cheers

Jem

If you're going to the trouble of drilling those holes- then I suggest you do a proper job.

You're going to have to empty out your shed anyway, and it would be a shame if the holes you made proved to be insufficient- so I would go for 10" diameter holes at least 3 ft deep.
In the uk you can get suitable tubes here
http://www.essextubes.com/column-formers.html


Holography should be built on solid foundations

[Jem]

You're going to have to empty out your shed anyway...

What!!!!!!!!!!!!!!

, you haven't seen my shed

Nah, I think i'll just stick to trying to drill some 5" holes and take it from there.

Thanks for the suggestion though, it gave me a right good laugh

Jem