Plastic Hinges a warning

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Dave M
Blackwood
Posts: 250
Joined: Tue Jul 15, 2014 6:44 am
Location: Somerset UK

Plastic Hinges a warning

Post by Dave M » Fri Mar 23, 2018 5:05 am

When I built my binding ledge cutting jig I couldn't source the big plastic hinges that Trevor used (in the UK) but ended up with smaller ones.
I have been reworking the jig to fit a different router and discovered that one of these hinges is very nearly broken through at the hinge point. This could be seriously unpleasant if they gave up while working on a guitar! This setup has only done half a dozen guitars.
bind 1 small.jpg

I have moved to this arrangement hoping for a bit more rigidity:

So if like me you have had top use relatively weak hinges do check them every so often.
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bind 2 small.jpg
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Dave

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Trevor Gore
Blackwood
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Joined: Mon Jun 20, 2011 8:11 pm

Re: Plastic Hinges a warning

Post by Trevor Gore » Fri Mar 23, 2018 9:17 am

Thanks for the warning, Dave. It's definitely worth taking a close look at the specs of anything that's critical. For the hinges I used it was something like 50kg load bearing (per hinge) and a very high number of cycles. They were meant as substitute domestic door hinges and intended to last a few tens of years. The ones I've got are ~10 years old now and are fine.

An alternative which may be easier to find in other parts of the world (were hard to get here) are nylon or HDPE hinges with stainless steel pivot pins. The holes are tight but still move easily enough. Used in the boat building trades (and likely also for caravans).

Here's an example. Can't remember these being around when I was last looking.


The weather looks just like it did when I left the UK....

Dave M
Blackwood
Posts: 250
Joined: Tue Jul 15, 2014 6:44 am
Location: Somerset UK

Re: Plastic Hinges a warning

Post by Dave M » Sat Mar 24, 2018 3:34 am

Yes it's been a seriously dull period this winter but at least the snow has now gone. Yes, 100-150 mm of snow in mid March!


Still makes the warmish, dry workshop all the more attractive.

Finished the reworking of my binding jig today and, along with the much higher quality DeWalt router I am expecting a better performance than my rather crude version of your design.
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Dave

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