need help with a sketch

[Anonymous]

hi everyone,i am sorry if this is the wrong place to ask for this.I have to re-create the file impl_fin.stl but without the hole in the middle,i think that i have done the base semi-decently in part2.ipt but i am having trouble with understanding how to create the four corners of the model(i think that they were made with removing material but not sure).can someone give me some tips on how to do them or if possible share a picture of which planes i have to do or sketches,i will be very thankful.i am using inventor pro 2015 and don't know the dimension because i wasn't told.thanks if you can help and i am sorry if i am bothering you.

[Anonymous]

Can you upload the steps until the extrude next to save some time if possible.

[JDMather]

I am not sure what you did - but you left behind an extra point that should not be in the sketch.

Drag that point up/down vertically.

Where did it come from?

Delete it.

[JDMather]

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@Anonymous wrote:

Can you upload the steps until the extrude next to save some time if possible.

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You missed the two Tangent constraints to the circles as I instructed.

[cbenner]

@JDMather Easy big fella.... bedside manner my friend.

[Anonymous]

sorry i was in a hurry becusei had to help my parents with something and forgot.i added the tangent to the lines.the dot in the middle seems to be connected to the constrain of the bottom lines so i can't delete it.

[Anonymous]

in test 3 i decided to go a little ahead and see how the extrude looks.i thinks that it's pretty nice and if you also think so we can go from there.otherwise we can continue with test part.

[JDMather]

Your instructor will have to become involved for me to continue beyond this point.

I need a complete description of the assignment.

[Anonymous]

well he gave me some detail about the implant.it serves to secure the first two cervical vertebrae in the human neck.it will be made on a milling machine center and is made from a titanum alloy.The screw holes are smooth without threads with spherical sockets to hide the screw head.if this doesn't help then thanks for trying to help me.

[JDMather]

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@Anonymous wrote:

...it serves to secure the first two cervical vertebrae in the human neck....

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Do you have a scan of the vertebrae?

This is an very highly advanced assignment.  I am not sure that your instructor understands the complexity of the assignment - which as an educator is a real concern to me.  Assignments should match the level of instruction that the instructor has provided.  You have been given a nearly impossible assignment.

I would have to complete the difficult portion of the assignment for you and then explain each of my steps (just as I did for the simple sketch, but as you can imagine the difficult portion could take us several weeks.  This is what your instructor should be doing.  When is the assignment due?

If you have a scan of the vertebrae there might be a bit of a short-cut to the solution.

I really think your instructor should be involved directly in this discussion.

Why is your school using 2015 SP0 when students and schools can get the latest version of Inventor for free.

Is this a commercial project.

It makes it all the more difficult to communicate when a very old version of Inventor is being used.

[Anonymous]

i don't have a scan of the Vertabrae.in reality i have to do an analyzis on the implant(constrain,force,etc) and then apply a Lattice structure to it using Autodesk Within but without the central hole.Unfortunately i need a solid model for that but every program i have tried so far hasn't worked for me:Solid Works crashes,FreeCad crashes,Fusion360 can work with only 10000 faces while this one is way over that,MeshLab doesn't have an option to convert to edible file,InStep crashes and Inventor Mesh Eabler also crashed.i though about the sketch but it looks like that will be way too hard.i think that i will just ask in the forum if someone can convert it to solid so that i can edit the hole and do the analizys.

Thanks for helping me.I am sorry for any inconveniences caused by me and sorry if you lost precious time because of me.

[JDMather]

A good portion of the geometry is standard b-rep as you have already extruded.

You need convert only the non-standard geometry to solid body and add to the b-rep.

I would trim away most of the mesh in MeshMixer, convert that to "solid" in MeshMixer and then bring over into Inventor and run the AutodeskMeshEnabler to convert to a true solid body and Combine with your extruded b-rep body.

Your instructor should be very useful in helping you complete these steps.

If I find the time - I will create a video of the steps over the weekend.