Path, Union tool to create a hole with tabs

[adbuch]

This is in response to a fellow member who recently asked the following question.

Hard to explain what I want to do. I want to make a plate that will house a 3157 (automotive) turn and lock bulb retainer.
The inner hole is about 1.070 that will have the cut outs on each side to the socket goes in a then you turn the socket so it locks. There will be cut outs on each side. I am having difficulty getting just one side of the cut out to work. I made a circle and made the stroke width to be .130" wide as that is the tang size of the plastic socket I have. I then manipulated the circle with the wider stroke to the height I want. When I go to do a union the kickout tang size is smaller like it is not taking may arc as an object. I know I am missing a step. I have to do the exact tang kick out to the right side as well but not as tall.

If I am correctly understanding what he is trying to do, then this is my solution as one way to accomplish this task.

David

[TJS]

So an automotive twist light socket is a little different. Here is what I came up with. I drew the minor diameter circle first. I then calculated the tabs by measuring the socket tabs and added that number by itself again. This gets the major diameter of the tabs. I then needed to know the height of these tabs. I measured those. Then I centered the smaller circle in the larger circle. Put a box to the left of the circle with the correct height and double clicked on the outer circle to get the nodes, then manipulated the outer circle to get the tab next to the height of the box, then did a union. For the one on the right I did the same thing but I had to hide the center object so I could see the outer circle.I did the same thing to the right side to get the tab.

[TJS]

Thanks David. I am going to do a cut and see if my bulb socket fits.

[plasmanewbie]

Great info here guys, learned a few things from it, thank you. Curious how it works out for you TJS.

[TJS]

Ok I did a test cut with some junk. Had to make some adjustments so I figure I would re draw it and take screen shots how I did it. I am sure there are other ways to skin a cat with inkscape. I hope these come out in order.

[TJS]

Continued

[TJS]

continued. Once I cut it out and get a good test I will incorporate this into my snowplow light project where the 1157 sockets do not even come close to holding a light bulb. The plow light housings are prob 25 years old with minimal use. Wonder why.

[TJS]

Sorry for the small font in my screen shot. I have to remember in Paint to make the font bold and bigger.

[TJS]

Ok. It worked. Locks in nicely. Now I need to incorporate this into a double socket holder bracket.

[adbuch]

TJ - Thanks for that great explanation showing how to start with a hand drawing and turn it into a useful finished part using Inkscape to create the vector file. I followed along with your process, but I duplicated the larger circle and moved it off to the side before I did the first union. That way when I snapped it back to create the second union, the round node was on the correct side so I didn't need to flip the circle over. Great work!!

David

[Dirtmotor]

Thanks TJ and David for more ideas on ways to use inscape .

[TJS]

Here is the junk sockets in the plow light housing that don't work at all.

[TJS]

Here is my part cut out. Double socket. I had to clock it so the sockets sit correctly in the housing. I will modify the housing a little to get proper fitment. More to come. Some of you may ask why not just make the part longer so the sockets fit. Well I measred the white lense in the pic where the light bulbs would be and center to center they are 2.250".

[adbuch]

TJ - that turned out great! It's really nice when a project comes together like that. I expect you probably fiddled around with your kerf width setting to get the size dialed in just right for a snug fit - but that's "par for the course". You provided a great tutorial from start to finish.
Thanks!!

David

[TJS]

Thanks David. I made one adjustment after I cut the test piece. Then cut the double one out. I changed my lead into a different start point and really have no divot. Just need to make another one and get this project done. Can't wait for winter.

[adbuch]

Thanks for that update TJ. I think your project turned out fabulous!

David