Sourcing true 5mm Plexiglass?

[smorgasbord]

I'm trying to find some actual 5mm thick plexiglass for some jigs I'm building.
I had some old (as in several years or more) plexiglass lying around that was slightly thicker than 5mm, but definitely not ¼"

I recently bought a small piece from Amazon that claimed to be 5mm, but is actually 4.6mm thick. And I saw a listing on Amazon for ¼" plexiglass that admits it's only 0.220"-0.236" thick.

Since the thickness of the plexiglass affects the depth of cut on my Domino, I want as close to 5mm as possible - if not exact then slightly thicker.  I'm thinking of going with the ¼", as 5mm is just about 0.2" so a couple/few hundredths more is probably just fine.

Is all so-called ¼" plexiglass actually just 0.22"-0.236" thick? Is there anything closer to 0.20" without being under? Am I being anal-retentive? (that's rhetorical [embarassed])

 

[woodferret]

US Plastics jumps from 4.5mm to 6mm, skipping 5mm.  I'm guessing that's where most of your full sheet plastics is coming from.

 

[Cheese]

Tap Plastics also offers metric sized acrylic sheets, but they too go from a 4.5mm to 6mm thickness. [sad]

 

[Packard]

I did not realize that Lee Child, the author of the Jack Reacher books, was British until he used “Perspex” in one of his novels.  It was a give-away that the author was British (though the person speaking was supposed to be American).

The British term for “Plexiglass” is “Perspex”.  When I google “5mm Perspex”, I find some at 3/16”, and at 0.1875”, but also a few at “5mm”.

Amazon, EBay and Etsy all list 5mm inventory.

You can also use your Amazon account to buy stuff from Amazon.uk (England); Amazon.es (Spain) and Amazon.de (Germany).

The UK site is in English; The .de site has an option to give English translation, as far as I could find, the Amazon.es does not offer a translation, so you need to be able to read Spanish.  All of them should carry 5mm sizes.

Here’s my Google search:
https://www.google.com/search?q=5mm+perspex+sheet+price&client=firefox-b-1-m&sca_esv=a9cf2f83da618f78&sxsrf=ADLYWIJfA6wGQH3wMsFDGc--XC_L6cmgAg%3A1736281176233&ei=WIx9Z572DcyuptQPjfjmmQQ&oq=perspex%2C+5mm&gs_lp=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&sclient=gws-wiz-serp#pvs=0

 

[Michael Kellough]

McMaster has 3/16” cast acrylic that is supposed to be between .021 and.023”.

But I recently bought a couple pieces of 2x2 aluminum 90 degree angle that measured 96 degrees so…

 

[Steve1]

At least the McMaster Carr pieces give you the actual tolerance on thickness.

Their standard 3/16" cast acrylic tolerance is -.043 to +.007", which gives a middle of .163" = 4.14mm
They have a few different types which have slightly different tolerances, but I don't see any particularly close to 5mm

I would expect the pieces to tend towards the lower end of the tolerance zone, because that means less material and less manufacturing cost.

 

[woodferret]

I would expect the jump to be more inline with the J channel extrusions which also jump from 3/16 (4.762mm) to 6mm.  While technically, most 3/16 J channels are wide enough at the bottom to accept a 5mm, it's gonna be really tight and a PITA to get anything in.  The bias in tolerance towards the lower end also reflects that tight fit.

 

[bobtskutter]

Could you thickness a piece of wood to the required 5mm thickness?  Or maybe 3D print a suitable component?

Bob

 

[Packard]

This EBay seller’s site (found by googling “Perspex”), has all dimensions in millimeters.

Ships from Wellingborough, UK with an estimated shipping charge of $27.00 which dwarfs the part cost of about $6.00.

I did not search any other Perspex vendors, but it is likely that all of them are going to be UK locations.  It really becomes:  How important is the 5mm thickness.

Note:  Perspex is not a lower quality product.  The name stuck from WWII fighter plane cockpit windshields. 
https://www.ebay.com/itm/232405252828?gQT=1

GBP 21.67 (approx US $27.04) International Priority Shipping to United States via eBay's Global Shipping Program. See detailsfor shipping
Located in: Wellingborough, United Kingdom

 

[squall_line]

From reading other threads:

This is for a see-through jig plate for the DF700 and/or DF500.

Clear is important because it's for a see-through jig.  This likely rules out 3D printing.

5mm (or, more specifically, a known thickness) is to minimize the overall effect on the plunge depth.  6mm would reduce the effectiveness of the jig for deep mortises, 4mm may or may not work if it was known to actually be 4mm.

In that sense, milling and polishing 6mm down to 5mm would be one of the only ways to get a uniform 5mm thickness, and that sounds like a lot of additional effort.

I only mention these items to help guide the recommendations, since some of the suggestions are good but just not for this application.

 

[Packard]

Fielect lists 0.200” thick Perspex (vs. 0.19685” = 5mm) through either direct or Amazon.com or Amazon.ca (Canada).  I think they are Canada based. 

You will have to contact them for tolerances.
https://www.google.com/search?q=fielect+clear+5mm+perspex&client=firefox-b-1-m&sca_esv=0da12726fba0ca1f&sxsrf=ADLYWILlAfCwyC-qUoIQDKy1Ki_Dqr_kug%3A1736352273072&ei=EaJ-Z5aBBN7Tp84PtvvVwQQ&ved=0ahUKEwjWzcOjwOaKAxXe6ckDHbZ9NUgQ4dUDCBA&uact=5&oq=fielect+clear+5mm+perspex&gs_lp=Egxnd3Mtd2l6LXNlcnAiGWZpZWxlY3QgY2xlYXIgNW1tIHBlcnNwZXgyBRAhGKABMgUQIRigATIFECEYoAEyBRAhGKABMgUQIRigAUirvwFQ2QtY5boBcAJ4AJABAJgBmgKgAfYeqgEGMC44LjExuAEDyAEA-AEBmAIVoAKUIcICCBAAGIAEGLADwgIHEAAYsAMYHsICCRAAGLADGAoYHsICCxAAGIAEGJECGIoFwgIEEAAYHsICBhAAGAoYHsICBhAAGBYYHsICCBAAGIAEGKIEwgIFECEYqwKYAwCIBgGQBgqSBwgyLjYuMTIuMaAHlUg&sclient=gws-wiz-serp

The Plastic Shop (UK) compares Perspex with Acrylic sheet.
https://www.theplasticshop.co.uk/perspex-faqs.html#

What's the difference between Perspex® and acrylic?

Perspex® and acrylic are essentially the same thing. Perspex® acrylic is a premium branded acrylic and, as such, is manufactured to the highest industry standards possible. Perspex® acrylic has an enviable reputation as the very best acrylic available.