Home » Uncategorized » (Wonkish) Here is the precise description of the gasket material

(Wonkish) Here is the precise description of the gasket material

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Note the material is 0.02 inches thick, and if it were mild steel, would provide ample protection. The specs I found on the product reported a blockage of 45 dB at 1 GHz. Nothing is listed for VLF frequencies, although the blockage will be not as good. What I will do is cut a 24″ by 24″ hole out of the top of the box, smooth the edges, glue the gasket down, then prepare a 25″ by 25″ piece of steel that will simply lay on top of the hole. (There will of course be an overlap. The gasket is 3/4 inch wide). Then, perhaps 20 kg of weight will be applied to the “hatch” door when the unit is being used. Virtually any participant will be able to push his or her way out of the box should any urgent need arise. As for a micro air hole, I still have a few days to decide how to handle that one.

20150908_184017


4 Comments

  1. George G. says:

    Glen,

    CAUTION!

    Is the ‘glue’ an insulator???

    You may be defeating the purpose of the seal if you spread a film of insulating material between the box and the seal.

    G.

    • My understanding is that the gasket has an adhesive backing, and so electrical properties should not be affected.The gasket itself will be the only gap between the two pieces of steel.

      • George G. says:

        Very good.

      • jimvandamme says:

        The key is to keep both the door and the box flat, so that they contact the gasket material. You don’t need much compression to make a nice low resistance connection, but if you put too much pressure on and the wall deforms a little you might not get a continuous seal.

        You might be able to read the resistance between the pieces with an ohmmeter, but it will (you hope) be almost like a dead short.

        I’ve seen similar material used on many RF-tight boxes in military applications.

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