Hello

Can any of you recommend a UK supplier for good quality "mill board"?

(Clue: My understanding is that "mill board" is very much like grey board, but it is a virgin material and tends to be very much stronger. It is recyclable and it does not have to toxic/carcinogenic chemicals contained in MDF)

I need a thickness of about 1400 or 1300 microns (1.4 or 1.3mm) thickness. I have found some good stuff by the supplier has a Minimum Order Value of £330!

It is for a model-making project. Grey board is WAY too soft.

Many thanks

J

I have been off-grid, hence the delay in responding.

Yes, I have already experimented with a wide variety of materials.

MY REQUIREMENTS

1. I need a material that is as broadly "eco-friendly" as possible.
"Grey board" (being made from some kind of recycled paper/"dead trees&quot is the default material for hardback books and the like but it is way too soft and creases permanently very easily. "Mill board" appears to be a virgin material that is a much better engineering material. Yes, there are many different grades – I am open to suggestions. From what I can see most suppliers just seem to call it "mill board".

2. Thickness: The walls have to be made up from 2 layers of material bonded together. The total wall thickness must be no more than 3.0mm, ideally more like 2.6 to 2.8mm thick… Hence each layer should be about 1.25 to 1.5mm thick. Any smaller or any larger will be of no use to me.

One complicating factor is that for added strength and durability I may possibly bond a layer of craft paper, or 'eco-friendly' (recyclable/biodegradable) film onto the base material.

APPLICATION
Since you ask, my application is that I am creating a sort of A4+ sized box for indoor, room temperature use. I have already tried plywood but when you get less then 3mm thick the price seems to go through the roof. Also some plywood grades seem to be vastly more flexible than others of the same thickness.

For our 'box' structure to more rigid and generally strong the better. But resisting permanent damage through bending non-elastically is much more important. i.e. It is fine to be somewhat elastic/flexible if necessary, but it is not fine to be brittle nor to crease/crumple/wrinkle when bent.

If all else fails, I would also consider "Tawny Board" i.e. Kraft double-lined greyboard. The craft paper lining on both sides seems to greatly help the overall strength of the material.

All suggestions much appreciated.

J

@Bill Phinn

Yes, I have already had a few samples from JPP about 3 weeks ago – thank you so much for the suggestion.

Having spoken to them (James), they thought that their "JPP ARCHIVAL FOLDING BOXBOARD" (as per your link) would be too soft, as it is specifically designed to be folded and will not have the rigidity that I seek.
[No, I can't use creasing of the card in order to create a hinge for a number of of reasons – not least because such creasing has a positional 'memory' and I shall use some sort of fabric /cloth or liner material to create the hinges.]

JPP suggested their Heritage Conservation Board 1380micron, and sent me a sample of it, but it is way too soft and is for example very easily bent beyond it's elastic limit (i.e. creased!) between 2 finders and a thumb.

However much more to the point is their "Gemini Mill Board" – which is fantastic stuff!
e.g. I definitely cant bend their 1.5mm Gemini board between fingers and thumb. However my problem is that they simply don't make anything between 1.0mm and 1.5mm.

To get clear 1.0mm is too thin to have much strength and 1.5mm is too thick for my requirements.

[Part of the problem with the 1.5mm thick Gemini Mill Board is that it is unlined, and in order to make it durable and give it attractive, cleanable, moisture-resistant finish, I will need to bond some kind of paper, plastic film or book cloth onto both the sides of it once it is bonded into the 2 layers I need. And that will make it quite a lot thicker than my overall thickness (of the 2 layers) of being 3.0mm.

For example most of the protective papers & films that one can obtain from the likes of Winter & Company are between 0.15mm and 0.20mm thick. So assuming 2 layers of film – one on the inside of the box one on the outside of the box (especially allowing for a little adhesive) the total thickness in mm would be something like:

0.15 – Protective film (minimum)
0.05 – adhesive (guess)
1.50 – Gemimi Mill Board
0.05 – adhesive (guess)
1.50 – Gemimi Mill Board
0.05 – adhesive (guess)
0.15 – Protective film (minimum)

==> nearly 3.5mm (i.e. 3.45mm), which is a LONG way past my target of maximum of 3.00mm.

@SillyOldDuffer – all true. However I am trying to make something that a high volume, mass production licensee company would be interested in making, is low in cost, can easily be recycled as well as having a reasonably good strength-weight ratio.
– Steel that is tin-plated will be too heavy for its rigity
– Aluminium & brass are both too expensive

@Michael Gilligan – I googled DEF-STAN and got lots of UK MOD stuff. Is that what you meant?
I wasn't sure how to apply that to this situation.

@Roger Best – Yes, a Box file is close to it, however all the walls have to be the same thickness, and they have to be hinged accurately.

@Journeyman – Yes, I am extremely familiar with the Really Useful boxes. However they do not have collapsible side walls.

REQUEST: Please can everyone stick to my original question. I am just looking for UK suppliers of good quality "mill board"! For some reason I am finding them hard to locate through Google…

So still I need a strong Mill Board that is about 1250 to 1400 microns thick.

Cheer

J