Modding How to stop a hinged lid?

Hi all, looking for ideas on how to stop a hinged lid at a particular angle.

My current build is a cube-style custom built case. The top and sides form a lid that is hinged to the frame, allowing the whole lid of the case swing allow access to the components inside.




Here is what the case looks like:








Here is the action of the hinged lid:








I'd like the hinge to stop at approximately 135 degrees, like in my sketch:









Here's my first attempt as a possibility--a chain stop.








Open the lid, and the chain pulls out, then stops:








Any other ideas?



Thanks,
navig



ps. My work log is found here.

 

how heavy is the lid?

 

Pretty heavy as far as cases go. It's made entirely of 1/4" acrylic, with aluminum brackets, and the steel kikboxes grill. Maybe 5 lbs.

I think the chains will hold it--I'll probably reinforce the mounting points with some aluminum plates.

 

How about some sort of bumper or stop on the back that would physically limit the hinge from going too far? Make them so they look like part of the case back and not just "stuck on"?
John

 

how about a gas strut
if its mounted right it will open exacly how u want

 

I like the bumper idea on the back. Easier than trying to get ahold of a gas strut, not to mention they cost alot more. The chain will wear any paint off/scratch whatever it touches if that matters.

 

I like that idea as well. The only thing is that type of system will run him quite a few dollars/pounds. In this situation, it might just be best to KISS.

 

just an idea..
what about mounting a pair of these
http://www.diy.com/diy/jsp/bq/nav/n...refview=search&ts=1206693749371&isSearch=true
vertically on the back panel
the handles would then serve 2 purposes. they would act as a stop for the lid and also as a protector for the electrical connections at the rear.
all that would be needed additional is a small contact point on the case lid where the 2 would meet when it is opened.
could be something as simple as a rubberised thumb tack as long as its placed right

 

Hi all,

Thanks for the ideas. I went ahead and tried the chain stop method--and went down in flames. It's simply not strong enough. In fact, even a wedge stop is probably not strong enough. The lid exerts a huge torque thru the hinge, actually bends 3/4" MDF.

So I think I'm going to have to go with a strut of some sort, to get a more stable angle. Here's my basic idea:






The case is already huge, I could consider a rack like cobramods linked, but I think it would make the case take up way too much space. My current idea, the strut would fold back to the back panel.

 

http://www.rockler.com/product.cfm?page=16

Something Like that might help your case, but it opens 165*

 

Height (cm): 3.2
surely that couldnt be too much room considering the power lead itself sticks out more than that and the proposed strut design you would be looking at wouldnt be too much smaller .
would also save you the hassle of fabricating a pivot point and locking mechanism for the strut itself.

 

Could you not put a wedge down the whole length of the back? as per:

 

Thanks for all the suggestions.

Here's a small part of the problem, of using a wedge, or any strut that contacts the opened lid, close to the hinge:







Part of the forces involved--the contact point is going to act as a fulcrum. If the fulcrum is close to the lid, a greater force is going to be exerted at the hinge, which translates into torque at the back panel. Trust me, I can tell the quantity of torque by actually seeing the panel bend (and creak and moan).

Cobramods suggestion is good, tho, because the bracket itself will add stability to the back panel.



Being definitely impatient, I went ahead and attempted to fabricate my own hinged struts.

I had some aluminum channel sitting around, which I cut up:







With some temporary screws to act as pins, the channels came together to form hinged struts. By carefully placing the holes, the hinges actually have their own stop points.







And here it is action:







This works well, is quite stable, as a lot of weight is transmitted directly into the table. There is still some torque, so I beefed up the angle with some corner braces. And here is the point of having the hinged lid:


Completely tool free, and in a matter of seconds, I can have full access to pretty much all of the components in the system:






Now I just got to work on some of the aesthetics of my strut system.


Thanks again for the suggestions!

navig

 

Okay, so I finalized my design. Again thanks for all the suggestions.



Short of black paint, this is pretty much it:




For my feet, I picked up a cheap square of medium hard neoprene. Cut it with my scroll saw and a utility knife. Mounted within the channel like so:











For my hinge, I simply drilled a 1/8" hole and used some 4-40 screws with a keps nut.










Closed:









Opened:








And a nice little video:







Nice little bonus, I lubricated the hinges, so more squeaking.


Thanks,
navig

 

Nice! I seems to have worked out alright for you. Maybe if you paint those struts the same color as the case in the end, it will not be so noticeable and blend in with the case a bit more.