Lofting (I suppose) 1

[Creigbm]

Here is my situation. I have a cylindrical can and I wish to mill an 1/8" deep slot all the way around it. This slot however needs to be tapered such that the tool itself will move downward ('z' direction) as it is rotated around. This will give the appearance that it is spiraling downward as you rotate the can. I am trying to us a loft, however, I am having trouble establishing guidlines that will curve with the outside of the can while moving downward as well. I have some pictures that I can e-mail if that would clarify. Thanks for your help in advance.

Brian

 

[CorBlimeyLimey]

TheTick
OK, ignore that last post ... FYI, if I "open" the file direct from your site it works fine ... but I cannot do a "save" from it.

Creigbm
After seeing the files I am now more confused than ever (admittedly an easy task) but ... what are we supposed to see???

Other than the profile not being drawn on a plane perpendicular to the helix (which would be correct if a round cutting tool was used) & an undercut being shown in the jpg (but not in the part), I cannot see what is wrong.

So ... apart from working brain cells ... what am I missing?

from (the City of) Barrie, Ontario.

Everyone has a photographic memory. Some just don't have film.

 

[Creigbm]

The problem with this picture is the profile of the helical cut is the same as the revolved cut. I figured since both profiles are the same, I wouldn't get two different cuts as shown in the picture above. I was hoping that the two surfaces would mesh into one (like it should). I sent TheTick the model to so maybe he could post it on his website and look at that one to see exactly what is going on. All I want to do is make a revolved cut and a helical cut mesh together.

 

[CorBlimeyLimey]

OK ... finally I see what your concern is. The depth of the Extruded cut is the same as the depth of the Cut Sweep ... so there should not a visible line where the two surfaces join.

As your machinist correctly pointed out, the difference is so small as to make no difference in the real world, but if you were needing to do further work with surfaces in SW, this could cause problems.

I have tried various methods to eliminate the mismatch but without success & unfortunately I can offer no explanation.

Anyone else have any ideas? If not I would submit this to your VAR or SolidWorks to see if they can offer a solution or reason or identify it as a glitch.



from (the City of) Barrie, Ontario.

Everyone has a photographic memory. Some just don't have film.

 

[Creigbm]

Now we are speaking the same language!!! I am about to submit this to our VAR to see if there is a glitch and how to resolve this. Any ideas are welcome!

 

[TheTick]

You might be able to use Replace face or delete face to replace the split faces with a common surface.

 

[CorBlimeyLimey]

You got it TheTick ... Delete face (the helical base) worked like a charm.

Creigbm
You should still submit problem to VAR & SW.

from (the City of) Barrie, Ontario.

Everyone has a photographic memory. Some just don't have film.

 

[CorBlimeyLimey]

Oops ... that should have been Delete face & Patch

from (the City of) Barrie, Ontario.

Everyone has a photographic memory. Some just don't have film.

 

[Creigbm]

Indeed it did, nice work. I just submitted it to our VAR to see what exactly is going on here. Thank you all for your help, TheTick gets a Kudos for the day!

 

[Creigbm]

FYI: I spoke to our VAR yesterday and said that what I was trying to do was not possible because when SW creates a loft/sweep, it uses approximations which restricts it from creating a true curve. I was looking in the 2004 whats new in SW book and it claims to have improved the loft command so perhaps it will get better in '05. Thanks again for all your help.