I need a pneumatic thingamabobby!

lesrhorer

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OK, one big problem about buying something one needs is one must first know the name of the item, especially if it is an uncommon item, and it is and I don't. My mill has a little pair of metal bars that prevents the lid from opening too far and damaging various things, including the lid itself. They fell off the mill, and now they have come up missing. Of course, I could simply fabricate a new thingamabobby out of steel plate to take the place of the lost pair. A pneumatic thingamabobby that damped the motion would be much nicer. This shouldn't be too hard to fabricate, either, and then I wouldn't really are about the thingamabobby's real name. 'Thingamabobby' would be just fine. These shouldn't be very expensive, though, so I would prefer to buy one. I looked up "pneumatic lid stop thingamabobby" online, and for some reason my search didn't find anything. Should I have looked under "pneumatic lid stop whatsits" instead? What are these things called, and where can I get one cheap?
 

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Gas struts are a PITA to set up!

Hatch lid support springs work really well and the install is easy
 
Gas struts are a PITA to set up!
Um, OK. Why?
Hatch lid support springs work really well and the install is easy
Well, that one, at least, is way, WAY too big, but I am sure I could find some smaller ones. More importantly,however, I don't think this sort of thing would work, at least not by itself. This doesn't look like it provides a hard stop, which is necessary. The mill lid can fold over all the way to 180 degrees, which will interfere and possibly damage various objects. The lid needs a hard stop at just a bit over 90 degrees. Secondly, when the lid is shut, a spring will cause it to snap shut, rather than softly close, which is what is desired.
 
The spring is the hard open stop, it's straight when the lid is open. To close the lid, you push on the center of the spring and it folds in half as you close the door. That was the first size that came up, easy to make your own out of any size extension spring you need.

Gas struts take some trial and error to get the geometry just right, choosing the right force can also be difficult. If you do go with struts, build a simple mock-up to practice with!

McMaster Carr has a fantastic strut selection.
 
 
It took a bit of effort, but I calculated I can just squeeze in a gas strut (aka pneumatic thingamabobby) with a 155mm collapsed span and a 90mm stroke. This is one right here. At $3.98, it's going to be hard to beat.
 
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