Trimming one solid with another... Not happening

[v1406]

Dear all,

I am trying to model an electrical junction box but just cant trim some of the unwanted portions inside the junction box.

I have placed two solids, one merged into the other so that there is no gap between them and the transition is uniform. now i want to remove the extra bit of piece left inside.

surprisingly the trim command is not working ... please let me know where i am going wrong.

thanks in advanceACAD-electrical fittings.dwg

[Dadgad]

Welcome to the forum.

The TRIM command is used on 2D entities.
The command you want to use is the SUBTRACT command.
You might do well to open your MODELING toolbar or panel to familiarize yourself with
a selection of 3D modeling command options.

[v1406]

Welcome to the forum.
The command you want to use is the SUBTRACT command.

I want to retain the external coupler part and delete the internal remainder part. if the main body of the junction box could slice the smaller coupler....... it would serve. but just cant do it.

[v1406]

junction box explained.jpgplease forgive me for not being able to explain properly but i hope the attached image will help clarify the things better.

thanks again

[Dadgad]

I want to retain the external coupler part and delete the internal remainder part. if the main body of the junction box could slice the smaller coupler....... it would serve. but just cant do it.

Sorry, I just looked at your drawing, looks different than what I expected from your description.
Subtract is still a way to do it, but not using the existing solid.
Start by using the UNION command to combine the two parts into one 3D solid item, from which you will SUBTRACT the unwanted parts.
Create a new 3D cylinder of the diameter of the inside of your junction box and use that to SUBTRACT that shape from the
piercing solid. Then create another 3D cylinder and use that to remove the passage through the fitting and side wall into the box, also using the SUBTRACT command.

[v1406]

Sorry, I just looked at your drawing, looks different than what I expected from your description.
Subtract is still a way to do it, but not using the existing solid.
Start by using the UNION command to combine the two parts into one 3D solid item, from which you will SUBTRACT the unwanted parts.
Create a new 3D cylinder of the diameter of the inside of your junction box and use that to SUBTRACT that shape from the
piercing solid. Then create another 3D cylinder and use that to remove the passage through the fitting and side wall into the box, also using the SUBTRACT command.

is there a simpler way of accomplishing the job. may be i am complicating the things unnecessarily. please have a look at what i am trying to achieve.Junction-Box-.jpg

[nestly]

is there a simpler way of accomplishing the job. may be i am complicating the things unnecessarily......

The method you are trying to use is logical, but AutoCAD has some cool tools to automate things as well. Have a look at the demo below showing two of these tools: SHELL and PRESSPULL

http://www.screencast.com/t/enxMvb3UUq17

[StykFacE]

This is the way I would do it using the INTERFERE, SHELL, EXTRUDE, SUBTRACT commands:
*EDIT* After watching Nestly's video, his is definitely a preferred method. Me personally, the reason I use INTERFERE is because I've been caught in the past needing to edit certain "extremities" of a solid body part (for instance, flanged openings to a water tank). Using INTERFERE gives me my desired results, but keeps the objects separate from the "main solid body". For the record, in this tutorial of mine the final SUBTRACT does union the pieces - I wouldn't do this in a real world scenario.

Create solids first.


Use the INTERFERE command to find the interference of the two solids. Make sure to uncheck "Delete interference objects created on Close". Use SUBTRACT to omit this "extra mass" by selecting the secondary solid and the newly generated interference solid.


Reverse angle, main body transparent to see results:


Use SHELL to remove top face and shell the main body:


Create a Circle on the face of the secondary body:


Use EXTRUDE to create a mass into the main body. Use SUBTRACT to subtract this extrusion from the main and secondary body:


Final result is a complete body with the desired results.

[v1406]

The method you are trying to use is logical, but AutoCAD has some cool tools to automate things as well. Have a look at the demo below showing two of these tools: SHELL and PRESSPULL

http://www.screencast.com/t/enxMvb3UUq17

thanks a lot. mission accomplished.

but the basic question remains.... is there a way to trim the smaller cylinder along the inner surface of bigger cylinder? i am sure there is..... just want to know how?.

secondly i would like to know how to place a horizontal cylinder on the middle of the bigger cylinder wall? which osnap should be used as there is no reference point on the walls of big vertical cylinder. i know again this is not needed now.......but just to hone my skills.


img.jpg
thanks again for your help.

[v1406]

thanks for this alternative method....... i was trying to use the intersect command but didnt know how to use the resultant intersection. thanks again.