Hinge 19954 issue.

[Fieldtest]

Before I start I have tried image upload and have never succeeded in many years.

I have searched some images from lego catalogs to try and figure out where I'm going wrong here. I have inserted hinge 19954 into my moc and the door does not close or open properly. I understand there should be a small gap but I have seen many mocs built with no gaps. Is there a solution to open and close with no friction and/or maybe an appropriate link ?

The only way the hinge has worked for me for a door to close and open properly is from the Volkswagen 10220 but it has a 1 brick gap. I am trying to install the hinge seamless with no gaps..

Thank you.

Edited April 13, 2020 by Fieldtest

[imvanya]

Regarding the images, you should basically host your images on another site and link the images into your post. Please check this topic for tips on posting pictures on Eurobricks:

As to your actual question: the reason why the door gets stuck comes down to geometry. Consider these two assemblies:

In the top one the widest part of the door – the distance from the hinge axis to the furthest corner of the door – is greater than the widest part of the door frame. The door fits while it is closed, but as soon as you swing it open, that extra width becomes a problem. If you imagine a circle being drawn by the outermost point of the door, you will see that the door frame gets inside that circle, which explains why it gets stuck.

In the bottom one the widest part of the door is exactly the width of the door frame. Imagine that same circle drawn by the door. In this case, the door frame only touches it, so nothing blocks the door when you open it. However, it will need that 1 brick gap right by the hinge, as the door wants to go inside the wall.

With that in mind, it should now be clear why the gap is necessary. The alternative would be to somehow make the edge of the door narrower on the inside. For instance, you could do it like this:

The cheese slopes could be replaced with 6191, 37352 or other similar parts.

Edited April 14, 2020 by imvanya

[ExeSandbox]

@imvanya Wow that's an excellent presentation you did there! Despite the fact that I've been building for years, I never realized the geometry of the hinge rotation. 

[imvanya]

2 hours ago, ExeSandbox said:

@imvanya Wow that's an excellent presentation you did there! Despite the fact that I've been building for years, I never realized the geometry of the hinge rotation. 

Thanks @ExeSandbox! To me, the most fascinating effect of this geometry is how it is possible to build diagonal sections using this hinge:

Obviously, the same would work for other lengths as long as straight sections are one brick apart. Other configurations would require trickier calculations 

[Fieldtest]

6 hours ago, imvanya said:

Regarding the images, you should basically host your images on another site and link the images into your post. Please check this topic for tips on posting pictures on Eurobricks:

As to your actual question: the reason why the door gets stuck comes down to geometry. Consider these two assemblies:

In the top one the widest part of the door is greater than the widest part of the door frame. The door fits while it is closed, but as soon as you swing it open, that extra width becomes a problem. If you imagine a circle being drawn by the outermost point of the door, you will see that the door frame gets inside that circle, which explains why it gets stuck.

In the bottom one the widest part of the door is exactly the width of the door frame. Imagine that same circle drawn by the door. In this case, the door frame only touches it, so nothing blocks the door when you open it. However, it will need that 1 brick gap right by the hinge, as the door wants to go inside the wall.

With that in mind, it should now be clear why the gap is necessary. The alternative would be to somehow make the edge of the door narrower on the inside. For instance, you could do it like this:

The cheese slopes could be replaced with 6191, 37352 or other similar parts.

Hi I appreciate your detailed comments here. Very useful and informative.  I will apply this to my moc.