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mikegw1961

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I have just started the trial in Alibre and i am trying to find out how to draw a hole through the side of cylinder like a tee bar handle.

I get an error that I cannot select the plane

:wall::wall::wall:
 
You need to create a new plane, parallel to one of the axis of the cylinder. (insert referance plane is in teh reference group) Then draw a circle on that new plane and use extrude boss to turn it into a bar or extrude cut if you want the t-bar hole, length of extrude will determine if you go through one side of the cylinder or both

J

tbar.JPG
 
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IMHO no need to create a new plane. You can it is one way.
The way I would do it is select the xy plane then 2d sketch. draw your two circles with the centers at the point of origin (0,0) then extrude boss to depth.
then click on the orient right icon. select the yz plane . draw your circle then extrude cut through all. Takes less time to draw it than I took to write this.

Tubesketch_zpse6d574bc.jpg



Tin
 
Thanks Tin, I'm quite new to it myself, just tried your way and it is as you say quicker
 
Thanks Tin for your help. I will try that when I am home from work tonight.

Mike
 
Thanks for your help. I am going to spend a couple of evenings working though the tutorials.
 
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I have an Alibre question. I want to model a locomotive that is here in Maine. I can get access to the original to measure it. Should I draw it in Alibre with the real size dimensions, then somehow scale the whole thing when its done, or should I scale each part as I draw it?

I'd like to draw it full size, because then I could apply a couple different scales depending on what size model I decide to build, but I don't know how to scale a whole model.
 
I have an Alibre question. I want to model a locomotive that is here in Maine. I can get access to the original to measure it. Should I draw it in Alibre with the real size dimensions, then somehow scale the whole thing when its done, or should I scale each part as I draw it?

I'd like to draw it full size, because then I could apply a couple different scales depending on what size model I decide to build, but I don't know how to scale a whole model.


That choice is up to you Ron. When you do a 2D drawing to export to DXF for CNC make sure you scale to the correct size. What I mean is, if you scale your drawing to half scale it will dimension properly (full scale) in the 2D drawing but it will export the DXF at half scale also.
 
Ron,

I don't know Alibre, but drawing full scale and then reducing as desired is a common CAD modeling approach.

Thayer
 
I have drawn several parts full size in Alibre. When you are done you apply a scaling factor to the part and it is reduced to the scale you want. Then when you ask Alibre to build a 2D drawing of the part it will be in that scale. You can then print the drawing and take it to the shop for machining the part.

Dave
 
The problem I see is there are things that just aren't going to scale properly; hardware for one, and piping. I think my choice would be to scale it as I go; if you spend a bunch of time drawing it full scale and then shrink it you will have to go back and fix a whole bunch of stuff that isn't right.

Just my personal opinion,

Dave
 
I have an Alibre question. I want to model a locomotive that is here in Maine. I can get access to the original to measure it. Should I draw it in Alibre with the real size dimensions, then somehow scale the whole thing when its done, or should I scale each part as I draw it?

I'd like to draw it full size, because then I could apply a couple different scales depending on what size model I decide to build, but I don't know how to scale a whole model.

Good question Ron. I think you would want to scale it down first and make things like shafts and bolts a standard size. Down sizing from full scale could end up with odd sizes.
 
Yeah this is a good question about scale; I would do a few test parts on the CAD system first to full scale and add a few of these parts that could be an issue such a pipe and bolts; then do some scaling tests on it to see how things turn out.

Question of my own, how much is this CAD program anyone got the details?
 
http://www.alibre.com/
You can download and try for free. the basic level PE is $ 199 they do have specials. I got my licence for $ 99 and the full support and upgrades for $99 a year.
Tin
 
Tin, Thanks for the info, I think I might test it out.
 
In Solidworks & other 3D cad programs Ive used, its easy to scale individual part entities in 3 dimensions. Some scale commands further allow specification of reference point like the orign vs. the centroid etc. Others just do it & leave you to wonder how.

But from what I can tell in SW, this scaling capability doesn't seem to be available to assemblies, meaning individual parts put together with mates etc. Is Alibre the same?

Coincidentally I was just wondering the same thing - scaling a model engine up/down by some factor. I was able to apply scale it to all parts individually & then re-assemble those together as a new engine. But I could not do the same button-click scale command on the finished assembly original. Maybe I'm missing it or someone knows a trick?

But even if one were to draw the original project at its native scale & change it to something different, the new design would very likely need some TLC & scrutiny on many fronts: fasteners, bearings, clearance & interference fits.... Examples:
- a 0.001" piston clearance becomes a 0.002" clearance at 2X scale (but gas leakage probably still prefers 0.001")
- a 0.875" bearing becomes 1.050" at nominal 20% increase (likely unobtanium)
- a 4-40 bolt becomes ?? threads at even nice nominal scale factors like 50% or 200%
 
Thanks for the replies. I guess like so many computer questions there are always many answers. I think it does make sense to scale first and rationalize the sizes to fit common stock. Id hate to be turning shafts to something like .487 when a .500 would work just fine, even though it was a tiny bit off scale. But it would be easier to enter all dimensions as measured on the real machine and just let the computer do all the scaling.
 
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