Positioning of slots

peter_paton

Hi all, first plunge into CAD today, a ruler and pencil man usually!

Got on ok at a basic level with a bit of frustration here and there!  I was drawing a part that required two slots on the same plane, the slot tool worked fine but I had some difficulty with positioning.  Can anyone advise an easy way of doing this?

Cheers, Peter

henry_feldman

So here is an example of a very simple slot example (base square) with a construction line constrained to the origin lines. I will create a slot, and then mirror it over the axis line. That is a simple way, but you can also do the position of the lines that make up the slots, which can be constrained to each other (e.g. relative distances/angles/etc) or mirror over a custom line you make.

henry_feldman

So if you can show either a screenshot or the document, it would be extremely helpful. Also understanding what you mean by "difficulty positioning". Understanding constraints, construction lines, etc makes all the difference between wanting to drink coffee or vodka when dealing with parametric CAD, and so happy to help but need a bit more info.

henry_feldman

So here is an example of a very simple slot example (base square) with a construction line constrained to the origin lines. I will create a slot, and then mirror it over the axis line. That is a simple way, but you can also do the position of the lines that make up the slots, which can be constrained to each other (e.g. relative distances/angles/etc) or mirror over a custom line you make.

peter_paton

Thanks for the quick reply Henry.  
Link to file is https://cad.onshape.com/documents/4283581ceff19c4bf3f35e47/w/ea2b120bea0bb73828283e5f/e/6dbb19fcd923b8de1d42cec9  -  hope that works!

I used construction lines to help positioning but couldn’t work out if there was a way to get the slot to snap to a position.  I placed them manually but it was a bit of a fiddle.

Cheers, Peter

peter_paton

Thanks again Henry, the demo is really useful.  I didn’t think to try the mirror function though I did see it in a tutorial. 

henry_feldman

peter_paton said:

Thanks for the quick reply Henry.  
Link to file is https://cad.onshape.com/documents/4283581ceff19c4bf3f35e47/w/ea2b120bea0bb73828283e5f/e/6dbb19fcd923b8de1d42cec9  -  hope that works!

I used construction lines to help positioning but couldn’t work out if there was a way to get the slot to snap to a position.  I placed them manually but it was a bit of a fiddle.

Cheers, Peter

OK, not sure what you mean by snap to a position. Do you mean you want to drag them into position (transform) them rather than use sketch based constraints? Or do you mean you want automatically generated slots based on your first placement (e.g. one every 20mm or something x N number of occurrences). The second case is a feature pattern (either linear, curve or circular). In the example above I mirrored it over a axis line, but you could have simply placed the mirror line halfway between the 2 items and mirrored. The mirroring is the best method to get identical geometry since any change you make to one is reflected in the second one. There is also no reason in your sketch to have 2 sketches for 2 slots. If you put them both on the same slot it's easier to dimension between them for instance.

peter_paton

Thanks Henry, I am using some desktop publishing lingo when I say snapping - that is what I have been using for simple line drawings up to now.  CAD is a whole new language so I need to do a bit more study to get to grips with the basics.  Thanks for your help, it is much appreciated. 

henry_feldman

peter_paton said:

Thanks Henry, I am using some desktop publishing lingo when I say snapping - that is what I have been using for simple line drawings up to now.  CAD is a whole new language so I need to do a bit more study to get to grips with the basics.  Thanks for your help, it is much appreciated. 

By the way Peter, let me show you what pattern means, which is so handy. Linear patterns takes an object and makes copies along some axis of the shape at some interval, while a circular pattern makes a pattern around a point. You can pick the axis point to rotate around, and with some constraints (in this case I made a constraint against the origin) you can do some really cleaver things. Also patterns are not limited to sketch items, you can of course extrude something (a feature) and then pattern that. I have a very complex part which has 554 copies of the same feature around a circle, then selecting the circle copies the whole structure up in a line making an object that sort of resembles an ancient mace head. But I only drew one thing to make all that happen. And of course being parametric cad, if I modify that thing, all 554 change automatically. By the way I deliberately clicked on each line segment to apply the pattern as you may note it started doing the pattern as soon as anything was selected, which lets you make crazy patterns...