Problems hinging a compound curved door

[John Zay]

It seems that the door needs to have a dual action to clear the cabinet. Perhaps it could slide forward to clear the cabinet. Then it could pivot. This also means machining a custom hinge assembly.

[Harry Jeffery]

Sam
Sorry about the thumbnail, I suppose it is quite a non informative picture in that sense.

I can see an actuated arm working, but a good point that the lid stay is already made.


Jerry
Thanks for the clarification, I see what you mean now.

I may indeed have to reshape the 'jamb line' although getting the right shape might be difficult... but I suppose a 3D mock up would help though


John
I think I agree with the door requiring some sort of dual action if I wanted to hinge it in this way. however, for the door to clear the cabinet to allow for it to hinge successfully, the movement forward would have to be quite a lot. (I didn't put any dimensions onto the thumbnail, so you weren't to know)

Machining a custom hinge could be quite fun though



Thanks for all the feedback, it has been very helpful
Harry

[Yonak Hawkins]

Harry, you're so congenial. You answer each suggestion thoughtfully and individually.

[Joe Hillmann]

Look at how most car trunks are hinged. They often have large curved arms with the actual hinge point several inches away from the joint between the body and the trunk lid. The curve and offset lets the hinge points to be in line and the lid to swing way out of the way.

[Joe Hillmann]

This set up fits tight when open and close but gives several inches if clearance when opening.

http://www.youtube.com/watch?v=agi4FDZY61I

[Mark Bolton]

This set up fits tight when open and close but gives several inches if clearance when opening.

http://www.youtube.com/watch?v=agi4FDZY61I

When I see something like that I immediately think of the sketchyphysics plugin. The OP is using sketchup and any mock-ups could be done in real tests using sketchyphysics.

Just a thought.

[Harry Jeffery]

Yonak,
Thank you for your comment, I just feel that everyone who takes the time to post something after reading the problem should be answered.


Joe,
Thank you for raising that point, I hadn't thought of a car boot until now.

I think the large curved arms are more obvious on classic cars?...or is that just me?

I video link you posted is a clever idea which I think would work for my design, I'll have to model it to make sure though.


Mark,
I used SolidWorks for the image I uploaded, which I think has many of the features of the sketchyphysics plugin, but I also have made a real life model which I am testing various ideas from this post on as well.



Thanks for the feedback, it is all much appreciated,
Harry

[Mark Bolton]

Harry,
Typo on my part, was suppose to read "if" the op is using sketchup.

It definitely seems like a very tough challenge mainly in dealing with vertical sag. Getting any type of arm type hinge to be robust enough to not sag, even slightly, would seem a chore. I can only assume those doors will be quite heavy.

Will be interesting to see your solution.

[Harry Jeffery]

Mark,
I think you may be right about the doors having vertical sag and them being quite heavy.

I suppose these combined would wear the bottom of the cupboard out, so I might have to add a small roller to the bottom to try and prevent this from happening.



I'll try and remember to post pictures of the manufacture and the completed piece as well.


Thanks for the reply,
Harry

[Brian W Smith]

Just spitballing here and then have to hit the shop....

A regular,two leaf bttm hinge strong enough to support entire door,plus a safety margin.

Top hinge is a ball/socket style,that it's only purpose is to keep alignment.Reckon,you can make a std automotive reference....a bttm A'arm which is guided by the upper balljoint.Not the perfect comparison but you get the idea.

A yes,these would be "custom" made.

[Craig Regan]

Blum type hinges and shopmade mounting blocks on the cabinet? Possibly 180° hinges and creative mounting could get it done.

[Harry Jeffery]

Brian,

Firstly, thank you for the suggestions, but I don't think the structure would be strong enough to have a single hinge at the base of the door, the moment applied to the hinge at that point would be quite large, especially as I think I am going to have to use a frame to hold the door curve in place, which will only increase the weight of the door...

I suppose the way to help the bottom hinge would be to have the top hinge not only to keep alignment but to add support to it as well, but then we're back to the start again...


Craig,

The creative mounting of the hinges is my problem I think, there are too many places and possibilities for creative mounting, but thank you for the reply none the less.

Blum type hinges might work, but would there be enough reach in them to have the bottom swing out far enough to maintain a horizontal swing and have the top not sweeping into the storage space?


Thank you for the replies again, it has given me more to think about,
Harry