Autodesk Inventor

[#1]

Hi,

I am currently having a lot of difficulty trying to constrain an assembly.

The scenario is this:

I have a sleeve which I am trying to put on a shaft.The hole is quite large in the sleeve.  On the side of the sleeve (at 90 degrees to the big hole, is a smaller hole which which goes all the way thorough the sleeve.  This hole takes an L shaped handle in order to turn the shaft once it is all assembled (like the handle on a vice).  I am trying to insert this L shape into the small hole using INSERT, but the large hole keeps getting selected.  I have done the select other button(green button with little left and right arrows) but no luck, it is selecting the big hole as if it dominates the component.

Please tell me:

1. What I am doing wrong
2. How to make constraining these assembly parts easier and to be successful at it all the time instead of hit and miss
3. Is there a series of steps that make constraining parts much easier

I am really open to suggestions as this is the most difficult part for me in Inventor.

Thanks,

David.

[#2]

Can you share your parts with us? Just attach them here.

[#3]

As Jeff says, it will be easier to help if we actually have the parts, or at least some screen shots.  But it sounds as if you are trying to constrain a pin into a hole that is radial through a cylinder, correct? 

The insert constraint requires a flat surface and a hole normal to that surface, so you can't use that in this case.  Use a mate constraint between the pin axis and the hole axis, then some others (angle, tangent?) to further constrain the pin.

[#4]

The small hole probably isn't eligable for an Insert constraint if is cut through the bigger pipe. The insert constraint needs a round (flat) feature to work.

You may need to add some workplanes to use as constraining surfaces.

Paul 

[#5]

David, It is not possible to constrain the items you describe using the Insert command, there is no flat surface or plane to constrain to!

Instead, you can use the mate constraint to mate the axis of the shaft to the axis of the hole, then you can possibly use a tangent or another mate constraint to loacte the shaft in the hole, assuming you have suitable geometry to do that, or you could use an offset mate to constrain the origin planes.

Another way is to draw a sketch with a point or intersecting line drawn at the point you wish to constrain and use that sketch to constrain to. You can turn off the visibility of the sketch afterwards.

The possiblities are endless and it will mostly depend on the actual geometry you have to work with as to how you constrain the parts together.

I put together a demo assembly for you, but then realised, you have 2010 and I only have 2012 or 2013, so you wouldn't be able to open it.

If you would like, I can do a video that shows a few different ways of doing it.

[#6]

Hi, Yea thanks for your reply and for helping to do this. I find constraining really tricky as I often get warnings that something is wrong with the constrain and that I need to delete one constrain to make another. There was one particular time where it seemed that I could only use one constrain and couldn't use another one to complete the alignment of the parts (warning kept popping up). There was one part where I had to put a transitional constraint on a ratchet wheel and pawl (the arm that drops into the teeth space on the gear wheel). I tried every face of the pawl and the gear but it didn't constrain. I actually did an introductory course in inventor, and this was the hardest part I think for most people, including the instructor at times. I had a play around with solid works and found that it constrained a lot easier, but it wasn't the same parts that I tried. Also Inventor can keep you guessing, like when you are constraining lines before you extrude. It often says, one constraint needed, sometimes you can pull your hair out trying to figure out which it is, I am sure the programme can make a guess as to what it is or a suggestion and speedup things up (it seems to be super clever in other areas and tortures you just on that one constraint! - just give me the answer so I can get on with it, I feel like telling it). Anyway if you have a video link for me to go to I would appreciate it. I think what needs to be taught is the sequence of constraining. If you do it in a particular order of operation, you are more likely to constrain. Put down some basic rules; maybe where you place your planes as you construct parts, mate before tangent, etc . Also I find inventor dialogue boxes to be very primitive in comparison to the complexity of the programme. The command line at the bottom left of the screen is so 'after thought', diagrams in dialogue boxes are so small (bending sheet metal for example) and order of operation is not clear with some of the buttons, unless you have spent a lot of time with it. It puts people off when they are learning it because you have to remember a lot of stuff and if you leave the programme for an extended period of time and come back to it (like 6 months or so) the dialogue boxes aren't intuitive enough so that you can get straight back on and get going with it. The price that is charged for the full blown programme is like the cost of a small car and you would expect that it would give the average user an immediate advantage and a smooth learning path instead of having to be a doctor of it before you could really benefit from it. Anyway, thanks for getting back to me on that and look forward to your help. David.

[#7]

---

dcl1967 wrote:
 I actually did an introductory course in inventor, and this was the hardest part I think for most people, including the instructor at times. I had a play around with solid works and found that it constrained a lot easier, .... sometimes you can pull your hair out trying to figure out which it is, I am sure the programme can make a guess as to what it is or a suggestion and speedup things up (it seems to be super clever). 

---

You need to find a different instructor.  Constraints in Inventor are completely logical.
I have not found any significant difference between Inventor and SolidWorks (I teach both).

The program as absolutely zero cleverness.  It is a software program.  Neither the software or the computer has thinking ability.

Once you understand constraints they should be rather obvious.

Inventor is a professinal program and deserves (demands?) a professional level of preparation.

Attach your assembly here if you want instruction.

[#8]

David, while it would be nice to have some of the icons be a little larger and more descriptive, you have to remember that this software is aimed at professionals. That is, people who have degrees or at least a lot of experience in the work that they do, and for them, the enhanced icons etc... are simply not needed. And that could be the case for you too, soon we hope ... lol

I agree that Inventor, like any professional software, can be difficult to learn, but that in itself is the challenge don't you think?

Imagine what you can achieve if you have a first class knowledge of Inventor.

It's good that at least you have sought some professional help in learning Inventor, but if the Instructor is having difficulty, then as JD said, find another Instructor, because that one is seriously lacking knowledge and that is something that you NEED!!.

I will put together a quick video that shows a couple of ways of constraining for you. I'll post the link when it's done, in an hour or two.

[#9]

Hi JDM,

Thanks for your comments, I appreciate your help.  I managed to constrain all the parts except for the transitional contraint on the pawl and ratchet in this particular assembly.  I am getting the warning that i need to delete some other constraint before i do the transitional contraint.  Attached is the file, excuse the colours i was experimenting.

[#10]

Hi Andy,

Thanks for your encouragement and for the help from JDM.  Yea I look forward to the day i am natural with Inventor.

Thanks.  Look forward to your video.

David.