Plastic

[steve_b_wales]

I'm looking for a few pieces of plastic sheet (preferably black) that is approx 4mm thickness. I want to try and make a box cover for my homemade NV spotter so that it hides most of the light given off by the screen.

I need 2 pieces of 140mm x 120mm & 2 pieces of 100mm x 120mm. I also need one piece 140mm x 100mm

I've tried making a cover out of thin plywood but this didn't work. Basically, it has to be lighweight and strong.

Any ideas where I can purchase such material from?

[old'un]

Why not use aluminum?

[philm]

Some one with 3D printer could make you one.

[RockySpears]

How about the various enclosures by people like Maplin (or ebay or amazon etc etc) ?  There is bound to be one the right-ish size.

https://www.maplin.co.uk/search/?text=enclosure

Yours,

RS

[steve_b_wales]

Good ideas there. I can make it out of Correx, but it's a bit flimsy.

[Newbie to this]

I'd have a look on ebay, there's load of plastic sellers on there for not a lot of money, be careful of delivery though, I got some plastic rod from ebay with free delivery for a couple of quid, the rod cost slighly more but the free delvery made it way cheaper overall

[Mighty Ruler]

ABS styrene plastic sheet on eBay 8x12 1mm thick for £3.

[steve_b_wales]

Thanks for all the replies. I'll check out Ebay, and also see if I can strengthen the Correx I have.

[JohnfromUK]

I got some pretty much what you want, but in white to keep sunlight off a PIR detector, came from eBay and was just what was needed.

[Westley]

If you are unable to get black, have a look at a sheet of fly tying foam rubber. Thin, matt black and can be stuck with copydex or a spray carpet adhesive.

[sportsbob]

If you have a Model shop nearby they should stock it but it will be white and the thickest is generally 2mm.

[Mice!]

4 hours ago, steve_b_wales said:

Thanks for all the replies. I'll check out Ebay, and also see if I can strengthen the Correx I have.

What about the plastic sheeting you get to replace glass in greenhouses then stick the correx on if its black? The sheets cut easily enough and you can drill it if needed

[Walker570]

 

2 hours ago, Westley said:

If you are unable to get black, have a look at a sheet of fly tying foam rubber. Thin, matt black and can be stuck with copydex or a spray carpet adhesive.

You can get sticky back thin foam from the hobby shop.  Square section plastic down pipe may work and might just be the right size without cutting or pinning.

Edited November 30, 2017 by Walker570

[Westley]

1 minute ago, Walker570 said:

 

You can get sticky back thin foam from the hobby shop.  Square section plastic down pipe may work and might just be the right size without cutting or pinning.

I have used a white, square section, 90 degree elbow with the 'inner edge' cut away, to hide a wash basin waste pipe. It was quite rigid, even with the back removed and is probably around 3mm thick.

[steve_b_wales]

Thanks again for all the advice, much appreciated. I've made a basic one out of the black Correx I have. I'm going to fit pieces of very thin wood inside the box to strengthen it.

As mentioned, there's loads of companies selling plastic board via Ebay etc, and I intend to check them out soon.

[Yellow Bear]

Try here

 

--  http://modelshop.co.uk/Shop/Raw-Materials/Plastics/Black-or-white/Item/Styrene-sheet-black-1-0mm/ITM3862

[Blackpowder]

Bit late but have you had a look at square gutter sections?

 

Blackpowder

[mick miller]

Thin (model shop) aluminium angle for the joints, black correx for the edge - most sign companies have off-cuts of black correx. 3D printing is a nice idea but quite costly to print that shape and prone to damage for a spotter unless sintered or SLA.

[amateur]

I don't think that Correx would be robust enough for field conditions, but a 3mm Perspex container would do the trick and look professional

 

If you need to make the cover to an exact size, I can give you the method that I have seen used to make precise display cases from 3mm Perspex

Obviously these instructions were to make a 14" x 6" display case, but just adjust the dimensions to suit your needs and rather than making end-pieces, you just make a top piece - 

You need 3mm Black Acrylic/Perspex - eBay https://www.ebay.co.uk/itm/BLACK-ACRYLIC-PERSPEX-SHEET-PLASTIC-PANEL-MATERIAL-A5-A4-A3-IN-2MM-3MM-5MM/360875050516?var=630243151951&hash=item5405d44614:m:m62PqpnY8zVaQXb76_FBZ0Q

 

or off-cuts from a local sign-maker.

 

Cut a 14" x 18" piece with a fine-toothed band saw.

 

Get a 2' length of heating element out of a scrap electric fire and stretch it tight between two nails hammered into a plank of planed deal. 

 

Ensure that the Perspex can slip under the wire and is snug against it.

 

Wire up a 12v battery and check that the wire will heat up. You are looking for the wire to be very hot, but not glowing - you may need to introduce a variable resistor into the circuit to adjust the temperature.

 

Remove the protective plastic off one side of the Perspex and slip the Perspex under the cold wire, 6" in on the 18" length, with the naked Perspex against the wire. (You leave the other plastic covering on to avoid scratching the Perspex)

 

Switch on the power. As the wire heats up it will make the Perspex flexible and allow a 90 degree bend. The temperature and time is critical - too hot and you will scorch the Perspex - too cool and it will crack.

 

It is probably better to practice the bending with some off-cuts of Perspex before you attempt this with your final piece.

 

As the "floppy point" is achieved, lift the 6" length through 90 degrees, switch off the power and support the upright at 90 degrees with a block of wood.

 

Move the Perspex to the second 6" line and repeat.

 

You should now have a 14" x 6" U. (Obviously these instructions were to make a 14" x 6" display case, but just adjust the dimensions to suit your needs and rather than making end-pieces, you just make a bottom piece)

 

Get hold of some acetone (glass-fibre supplier should stock it) and put in a small oil-lamp, so that you can burn an acetone flame.

 

With the acetone flame carefully heat the cut edges of the U, which should result in a fine glassy edge.

 

Cut 2 x 6" x 6" pieces of acrylic and test fit against the ends of the U, sanding to size if necessary, then flame polish the edges as before.

 

Strip off the plastic protection off all the Perspex

 

Cement the ends onto the U with clear acrylic fixer.

 

It may take you a few months of trial and error to achieve the necessary skill to do this - but this method was used to make display boxes at a sign-making firm where I worked for many years

 

 

Alternatively the square drainpipe may be just as effective, as long as the dimensions work.

Edited November 30, 2017 by amateur

[steve_b_wales]

Again, there's some good ideas's and tips offered. I'll check them out later. The cover I want to make will be made to slip over the screen and not a permanent fixture.

[steve_b_wales]

Now sorted.

[amateur]

Go on, then, tell us what you did

[old'un]

Well what a let down…..I was waiting for you to come and tell us you had all the materials and were ready to start the project accompanied with hundreds of pictures.

[steve_b_wales]

On 01/12/2017 at 16:08, steve_b_wales said:

Now sorted.

I should have said that Strongman, on here, gave me some pieces of 3mm plastic sheet, cut to the dimensions I wanted.

My thanks to Strongman for helping me out.

[Winston72]

as a footnote i have some white 3mm plastic sheet that's free to a good home if its any use to them, 8' x 4' i could cut it if needs be