Author Topic: Fixing a Moore & Wright level  (Read 24707 times)

Offline PekkaNF

  • Hero Member
  • *****
  • Posts: 2124
  • Country: fi
Re: Fixing a Moore & Wright level
« Reply #25 on: September 19, 2018, 03:09:47 AM »
Does anybody have this file in PDF or print with pictures?

I have bought two vials (libel) and like to make level on my own. First post might help on my question on "How to mount vial into tube".

Pekka

Offline seadog

  • Full Member
  • ***
  • Posts: 170
  • Country: gb
  • NE London
Re: Fixing a Moore & Wright level
« Reply #26 on: September 19, 2018, 03:50:24 AM »
Plaster of Paris is the usual way to fix the vial, Pekka.

There's a thread on the Mig Welding forum that ought to help.

https://www.mig-welding.co.uk/forum/threads/boxford-lathe-help.83731/page-2#post-1203582

Offline mattinker

  • Hero Member
  • *****
  • Posts: 1109
  • Country: fr
Re: Fixing a Moore & Wright level
« Reply #27 on: September 19, 2018, 06:04:35 AM »
Plaster of Paris is the usual way to fix the vial, Pekka.

As Seadog says, Plaster is the traditional way, but people are using Silicone now.

Regards, Matthew

Offline PekkaNF

  • Hero Member
  • *****
  • Posts: 2124
  • Country: fi
Re: Fixing a Moore & Wright level
« Reply #28 on: September 19, 2018, 02:12:28 PM »
Thank you. This business with POP is perplexing. I don't get it. Is it stable after it has air cured - week?month?

Pekka

Offline mattinker

  • Hero Member
  • *****
  • Posts: 1109
  • Country: fr
Re: Fixing a Moore & Wright level
« Reply #29 on: September 20, 2018, 05:58:15 AM »
Pekka,

Plaster of Paris is stable once it's "gone off", initial hardening is a reaction in which the de-hydrated plaster takes up the molecules of water that were cooked out of it to make it. It returns to to it's solid form, like the gypsum it is made from. Once hardened, the excess water will then dry out. Plaster is stable once set, although it will shrink, not much, but on large objects, reinforcing can be required to prevent cracking. Plaster is very variable, the fresher it is, the faster it will "go off" (initial hardening) the amount of water will vary the final hardness. I love it, but I've used it a lot and I know how fickle it can be! The theoretical quantities are equal volumes of water and plaster, whenever I buy plaster, I mix a small amount (equal volumes) to see how it goes off. New, freshly baked plaster will go off faster, try and buy from a place that has a high turn-over, old plaster gradually takes up damp, even in in plastic bags! I have sometimes been able to buy plaster that was still warm from the kiln! It is so much better!  Once it's gone hard, it should for all intents and purposes be stable, even before it's completely dry.

I have a project that requires 2 vials (Kingway tool) I am going to use silicone for simplicity!

Regards, Matthew

Regards, Matthew


Offline PekkaNF

  • Hero Member
  • *****
  • Posts: 2124
  • Country: fi
Re: Fixing a Moore & Wright level
« Reply #30 on: September 20, 2018, 07:32:43 AM »
Thank you much Matthew,

I was thinkking that silicon. I presume it is stable enough too? I started to think thermal and moisture properties of it and then started to think that it might not be as big problem as it intilaly looks if there is constant "ring" around the tube and reasonnably symmetrical to both ends. Sagging and thermal expanison shoud be to some extent self canceling.

You probably have a cunning plan?

I'm thinkking of using silicon as sealant/thin O-ring and check if it works. If it does not, then POP it.


Offline mattinker

  • Hero Member
  • *****
  • Posts: 1109
  • Country: fr
Re: Fixing a Moore & Wright level
« Reply #31 on: September 20, 2018, 04:36:00 PM »
Pekka,

Thank you much Matthew,

I was thinkking that silicon. I presume it is stable enough too? I started to think thermal and moisture properties of it and then started to think that it might not be as big problem as it intilaly looks if there is constant "ring" around the tube and reasonnably symmetrical to both ends. Sagging and thermal expanison shoud be to some extent self canceling.

You probably have a cunning plan?
Not yet, I'm still thinking about how I'm going to mount the tubes holding the vials.

I'm thinkking of using silicon as sealant/thin O-ring and check if it works. If it does not, then POP it. This sounds like the right track to me, keeping the thickness of the silicon minimal with something like short thin card tubes to hold thigs in place while the silicone cures.

Regards, Matthew