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

I think I would just go to the local stationers or visit Amazon and buy a really useful A4 box

John

@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

Can you make the core from one layer each of 1.0mm and 1.5mm which with the other items would give the total you desire.

Or if you want to make sure the structure is balanced then two of the 1.0mm with something 0.5mm in the middle of the sandwich.

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NO … I posted a link to the specific document, especially for your benefit.

MichaelG.

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Clause 4 is particularly relevant to ‘virginity’

Edited By Michael Gilligan on 14/06/2021 13:28:31

My browser (Brave) can't open this link.

J

Hmm... 1.0 +1.5mm isn't completely impossible, but it would mean fundamental changes to other parts of the design. Moreover if the product went into production the unwanted added complexity would add unwelcome cost.

So, yes, if all else fails... I'll guess I'll have to have another think about it but it would be must better to get two layers of mill board of the correct thickness!

J

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Then [if you want it] you will need to choose between using another browser, finding another source, or buying the 2003 version.

MichaelG.

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Edited By Michael Gilligan on 14/06/2021 14:46:33

John Smith 47
 

It seems to me that all your posts are of a business rather than hobby nature. i.e. you seem to be asking everyone else to do your homework so that you can make commercial gain from their advice.

I understood that this forum was for hobbyists.

Edited By Stuart Smith 5 on 14/06/2021 15:28:42

I am doing my best here but...

I have already tried opening that link (ftp://ftp.iks-jena.de/mitarb/lutz/standards/dstan/13/184/00000100.pdf) with several other browsers, however being FTP:// not HTTP:// all of my browsers are deferring to Brave.

I also tried opening directly from Adobe Acrobat Reader, but it throws an error message:

I wonder what "waste" paper really means. Is that the same thing as "recycled" paper?
My understanding was that if the paper has already been used once, then when it is recycled, it now becomes called "grey board" not "mill board", and that "mill board" is a higher quality material that is "virgin" - i.e. it has never got as far as to the consumer.


@Stuart Smith - my hobby is trying to develop a product that might one day become a proper business and I am doing all this on next to zero money! Frankly until such time as I get any money whatsoever back from what I am doing I can't see how anyone could call this a business!

If you want the truth my main frustration in this thread, is that so many well-meaning folks on this forum start trying to give me design advice rather than answer a simple question.

Please know that I am not asking the question lightly. I have already spend a number of hours trying to find a suitable supplier of mill board, but I am finding it exceedingly hard to source mill board of a suitable thickness.

 

EDIT: Okay I have finally managed to get a new app "SumatraPDF" to open the PDF.
So there is a Defence Standard called "13-184/1" which refers to "Millboard And Millboard, Lead Free" which gives "requirements for millboard and lead free millboard for use in ammunition components".

I'm not entirely sure how this might help me... but I tried googling
>  "13-184/1" "millboard" UK

and 

>  "13-184/1" "mill board" UK

But got almost no results....

J

Edited By John Smith 47 on 14/06/2021 17:24:52

Revisiting the design is a common engineering tactic. When a 'simple question' about the material needed to satisfy a design results in unsatisfactory answers it may be worth changing the design. Always done when materials turn out to be Unobtainium, Unaffordium or illegal. Or the manufacturing process is too awkward, or has a high failure rate. Don't dismiss anything.

Another tactic is to defer the problem. When items are put into production manufacturers can resource almost anything, stuff can be specially made if necessary. In the meantime, build and test the prototype with something ordinary : who knows - the wrong thickness or a home-made laminate as suggested by Jason may be good enough.

All a prototype has to do is provide proof of concept - it doesn't have to be perfect. I suspect most products are developed after initial design, and Production Engineering is another game again. Only then dies it gets to the customer, who won't like the colour!

Don't be discouraged by suggestions. As you are finding, original design is the hardest stage in engineering. By comparison making articles from proven plans is a doddle, despite all the evidence to the contrary in my gigantic junk box.

Dave

Yes, all good points.

However where find myself to be conflicted though, is that I don't want to waste everyone's time analysing the full specifications & design constraints of the proposed product itself, which needless to say is rabbit-hole of quite a complicated balance of competing criteria... 

i.e. The design is fine - I am just looking for an alternative supplier who will deliver smaller volumes of the "WholesaleOnlyum".

Meanwhile, against the run of play, the supplier has relented and is now offering to do a one-off small order "to get me going", so I just order some more from them. Nonetheless I would dearly love to find an alternative supplier of 1250 to 1400 micron millboard, who is easier to deal with.

J

Edited By John Smith 47 on 14/06/2021 19:12:07

Can you enlighten us about the fundamental changes that having an unbalanced 1+1.5 laminate would cause? In your stack up:

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)

You make no mention of anything “in the middle”, and by your numbers it would add up to 2.9, just inside your sweet spot for thickness.

If you make it to production then presumably you’ll make an order for the right thickness of custom board, so no complexity there.

Dave

Oh crumbs... I really, don't want to get into the intricacies of the actual design...

[I'm going to regret this!]

OK, yes if one of the layers was 1.0 instead of 1.5, then my stack would now become 2.95mm thick instead of 3.45mm thick... and yes, that would be an ideal thickness.

However My problem is that:

A) To keep the number of different part designs down, the embedded plastic parts have to have rotational symmetry (i.e. the same design of part needs to work upside down)

B) Thinning the plastic connector down to 1mm from 1.5mm may weaken it too much and permit too much flexing - I'm not sure yet.

C) I would have to change my CAD models... and my problem is that my freebie license of my CAD software (SolidWorks) has now expired and so making the change would be expensive & time-consuming.

D) Finally, a potentially greater problem is that I have already got my plastic parts (in blue) 3D printed!

So as I have conceded, if all else fails then could re-do design, however all things considered, it would be VERY much easier at this point to just get some more c.1300 micron Millboard!

J

PS Please don't even try to understand what is really going on in my diagram, because what I have drawn is only a schematic and does not represent anything like the complexity of what is really going on at the pointy ends!

If you put the thicker of the two sheets towards the inside edges then you will not loose any strength as the "leaves" of the hinge will still be 1.5mm. Infact they will be stronger than if they had been 1.3mm.

Edited By JasonB on 15/06/2021 07:05:47

I don’t wish to interfere, John … but this may be of interest:

Many years ago I worked for a company which was an ‘early adopter’ of integral hinges: They found that flexing a polypropylene hinge immediately after moulding blessed it with a much longer service life. Non-flexed hinges were prone to cracking.

I have no real grasp of how the manufacturing technology might have changed since then, but [unless you are already familiar with such matters] this is probably worth a look: **LINK**

https://www.creativemechanisms.com/blog/everything-you-need-to-know-about-living-hinges

MichaelG.

How do you work that out?

We are trying to avoid living hinges because they always seem to have a positional memory if left too long in one position.

While it's wrong to use the forum to 'advertise' there's no ban on discussing professional work, certainly asking for advice on interesting problems or sharing unusual jobs is welcome.

Otherwise, we would not benefit from the input of many jobbing engineers, toolmakers, vehicle restorers, CAD and CAM experts and even on member who discusses his trackers and drones for keeping tabs on wild lion populations!

.

Sorry … I obviously misinterpreted your ‘Design Schematic’

MichaelG.

So there is an implicit symmetry in the stack up.
Fair enough.
can you get ~3mm board and mill the edge to the half thickness?

Thinking production you presumably will cut the parts from a larger sheet, so an additional op to thin the edges first saves a glue stack up op.

Dave