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Autocad LT and 3d/paperspace help req'd.

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Sirius2

Mechanical
Dec 15, 2002
67
Heres a question for you, lol.

We currently use an antiquated 2d system and I want the office to get something better for 2d mechanical design. AutoCad LT is perfect for our requirements (Mechanical is the best, but the budget is stupendously tight).

The dilemma is this:

We currently cant use/create views or manipulate 3d geometery for our 2d designs and have to time consumingly try and (very basicly) get the main bits drawn from scratch ourselves. This is often fraught with errors and is basicly a poor looking job.
I know autocad LT is not for 3d, but we generally only need to construct our fixtures or whatever around customer supplied information. LT has wireframe, a 3d UCS and the oh so important 'align' command.
This information sent is not solid data, but a badly drawn mismash of wireframe and some surface data. We dont always get paper prints, so we have to rely on the CAD data.

*right, on to the question* lol.

I was wondering about the possibility of opening the iges files of wireframe and surface data in Mechanical Desktop and saving them as an AutoCad file. This would open in LT as 'proxy objects'. So far so good.
The problem is now drawing the fixture around the data.

I was hoping to be able to draw the job in Paperspace, using views/viewports etc aligned up etc. The centers/endpoints of model geometry are still able to be picked up in paperspace even when viewports are not activated. The viewports (ie front top left view) would all be corectly aligned and scale to each other and locked.

Can you realisticly do this?. The only trouble I forsee is that when the job is bigger than the largest paper size. If we had to scale the component views in the viewports to half, our fixture would have to be drawn half size too....which isnt good.

Its just a crazy idea, yet it could save us so much time and work from what we have now. I know the proxy thing works etc, but the limitations of the drawing area in paperspace is throwing a spanner in the works.

Is there any further pitfalls or advice on this?


Thanks a lot for any response on this :)

Sirius.

 
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IGES, wow that's a blast from the past. I'm not sure AutoCAD still interfaces with IGES anymore.

I just have a comment about PAPERSPACE and SCALE. You don't have to scale the fixture to show a different scale. You just ZOOM in the viewport to the correct factor for the scale you wish to portray. ZOOM->1/2XP will result in a half scale view of the element in that viewport, just as ZOOM->1/32XP will result in a 3/8" = 1'-0" scale view of the element. DON'T FORGET THE "XP" behind the factor. You can preset the vport scale factor with PSVPSCALE.

Other than that you're on the right track I think, though I prefer solids over meshes and surfaces.
 
Yeah, the files we get sent are abismal. single thickness representations of parts in half surfaced wire frames. They just use wireframe for the most basic of shapes and a contoured face is surfaced.
I like solids too, but unfortuntely with these files we have to use its just not possible, lol.

The plan is to use MDT's iges import and farm it out to the rest of the office on LT.

I dont follow what you mean about scale.

For example, Its an exhaust pipe system fixture. The pipe at real world scale would just about fit on an A0 size sheet of paper. We would have to draw the fixture in paperspace over the top of the viewport of modelspace geometry....the viewports would be top, front and side, locked so they cant be zoomed to an incorrect size.

Therefore, if the exhaust pipe had to be scaled to half its size to fit top/front/side 'window panes' of the component and room for drawing the fixture over the top on one drawing sheet, the lines I am drawing would only be drawn half the size to match the component scale.

What I am struggling to explain is that whereas in normal use you would scale the viewport and scale the dimscale to match, I want to pysically draw my fixture in paperspace rather than just using paperspace for dimensioning.

I hope you know what Im getting at! lol. Its hard to explain :).

Thanks for your reply!. Im trying to understand it, but I dont think its where Im coming from. Imagine using the viewports as a substitute of a 2d orthographic projections of the component....then drawing the fixture on top of that piece of paper.

Thanks again,

Sirius
 
Why are you tracing the fixture? Build the model in MODELSPACE. It sounds like you're going to a lot of trouble to get something in PAPERSPACE that's already started in MODELSPACE.

Putting design elements in PAPERSPACE is a bad idea, those elements can not be xref'd into other design files.
 
How can you draw a 2d fixture in modelspace around 3d wireframe/surfaces 'proxy' information?. Is there a way to do this?

I know you can 'soldraw' and 'solprof' and all that in regular autocad, but we're not talking solid data here, and Im talking LT.
Theres only two packages I know which can create flattened orthographic views off of 3d wireframe data, and unfortunately Autocad isnt one of them(not even MDT can do wireframe view generation).
The management (for whatever reason) are still skirting the bigger issue on software, and therefore I suppose I am trying to replicate 3 true orthographic 2d views without costly software or redrawing from scratch because the data is useless to us.

In paperspace Im thinking you can create three orthographic 'picture frames' of the 'model' data. Therefore being able to draw 2d orthographic around the model *on-top* of the 'paper'. You can still pick up the Object snap features you see, to create the fixture correctly.

We could then create multiple more 'layouts' and copy/paste the fixture geometry from the first layout tab to the others, or even back to modelspace for detailing out purposes.

Im sorry for not being able to explain myself well enough :). I suppose unless someones in my situation they cant see the thing Im trying to get at, lol.

Its a crazy idea, perhaps totally undo-able, but if they dont wanna spend any money on software, and our current software is causing upto two hours a day of 'problem solving' (like crashing, unproductivity, "why does it illegal operation when we print?" and endless hours fannying about) besides the fact the data we have to use is useless........you can see why its an intresting proposal/crazy idea!.

Thanks for hanging in here with me, I know I must be frustrating with my inane questions.

Sirius

 
Your questions aren't the problem, I'm just completely out of touch with your delimma, and 10 minutes worth of explaination won't give me a complete picture of the situation.

Tha being said, let's clarify a couple of points. ACAD produces the views you desire, it just doesn't flatten the object to do it. ACAD uses different VIEWPOINTs in paperspace viewports to show orthographic projections of 3D objects.

Now you're stuck using ACAD LT, yeah, it's cheap, but you never get more than what you pay for. So your "tracing" idea might be your best bet.

A couple of things that might help, check with the guys sending you the junk. They may be outputting from MicroStation wire frame. If so, there are settings available to them during output that will make the drawing translation friendlier. Next make sure the bosses understand that saving a few bucks on software is going to cost them money in manhours to complete. If it takes you an extra $500 in manhours per contract to produce, better software will pay for itself in just a couple of jobs.

Sorry I can't be any more help, good luck.
 
I believe, I understand what seris2 is saying. And I think he needs to look at this from another view. Remember junk in junk out.
Request from your sources that you recieve a 2D file of the data. There will be static from the source, I know because I complain every time we have to do it for shops that can't or won't get on the 3D bandwagon. Then, do everything in model space. If your just looking at a plan view who really cares. You can still plot, use the plot scaling functions.

Fortunatley, after 2 years complaining, some of our sub suppliers are seeing the light, and moving on up to 3D.
Tteboe
 
If anyone in the loop on this data transfer has mechanical desktop, why not use the export view option that flattens a paperspace viewport?
 
Cheers all :)

In reply to billtati, even if we get a single seat of mechanical desktop, the parts of the wireframe which are not surfaced do not get drawn.

In reply to Tteboe, it causes a lot of hassle requesting 2d data, as you know. The drawings are japanese, then sent to its UK branch who are on Catia CADAM for Solaris. We cant contact japan really, because we are far down in the projects chain. I dont even think thier cad system at the UK branch can flatten wireframe views.
The nature of the job also requires 'true views' down compound faces (like looking direct on an endpipe flange) which we cant really go running back requesting these auxiliiary views too I dont think - which brings us back to trying do draw from scratch what we think it will look like, and errors will still occur.

If the company in japan would pull thier finger out and actually produce quality data (even if its just fully finished surfaces) things would be a whole lot simlper and a dedicated 'new' 3d modeller would get a better look in at our firm I think.
As things stand, a software like Solidworks/Inventor is still not much benifit given the nature of the data supplied.
It really is very basic cad skills, misjointed and often very unfinished, infact I would estimate it costs the big company here in the UK millions of pounds per year. It is not unherd of for complete bracket tooling to be made back to front or 'inside out' becuase the wireframe paper prints are so indistinguishable as to whats bending up/down and generally questioning what the hell youre looking at!.

A nice solidmodel, or even a finished fully surfaced model would eliminate 75% of the hassle. But we simply can not afford to re draw thier components for them as a surface/solid model, they really screw us down for delivery dates. You have to get to work straight away and bits are often made before the full design is complete.

In reply to Cadaver, I have been investigating. I believe you can turn off your paperspace 'sheet boundary' and therefore draw 1:1 ontop of multiple viewports at once. When it comes to plotting you can go back to the old days and set your plot scale to make it fit on a paperprint out.
We havent got LT yet. We really struggle on what we have to use now, the relatively cheap LT would be a 70% improvement! lol.

Im fed up of trying to pull miracles without training and software to do it, perhaps if I stop pulling them out of the doodoo as much as I do they may have to buy us something, but as I said, the data is pretty useless in a solidmodeller anyway.
At the present time, if theres any way to tackle a job using the 3d data we get now, without poorly attemting to redraw it, we will all be a lot faster and stress free! :).

I really appreciate all your replys on this one.

Thanks

Sirius2.








 
CATIA can produce output that is pretty slick, check with them on their end to see if they can fine-tune their product.

Another option is INTELLICAD PRO. It's not ACAD, but it is a powerful 2D/3D ACAD emulator that's cheaper than ACAD LT. (There's even a free, fully functioning demo version). I'd look into it seriously before spending cash on LT.
 
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