Learning to use CAD

Home Model Engine Machinist Forum

Help Support Home Model Engine Machinist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

tmuir

Well-Known Member
Joined
Oct 30, 2007
Messages
888
Reaction score
9
I decided I really need to learn CAD software so I can draw up some plans of all the parts I've made.

I've never used CAD software before and last time I did tech drawing was over 20 years ago in high school so I'm far from an expert in it.

I have dabbled with 3D software before so I do have some idea though.

After doing a search here I came across a post that recommended Alibre.
http://www.alibre.com/

It's free for their basic version and I must say I love it.

Here is a drawing I produced after playing with the software for an hour or two.
Its for a pulley I need to fabricate, yes I forgot to put the groove on the pulley and the hole for the grub screw but for a first play I was quite pleased with it.

The second drawing is for the safety valve and whistle bush and yes a whole a4 drawing for this bush is overkill but I did this drawing really just to have another play with the software.
This drawing took me about 20 minutes to do and I'm sure with practice I would get a lot faster.

Got to say I really like this software.




View attachment Renown_Pulley.pdf

View attachment Renown_bush.pdf
 
Hi Timur,

I have it too. Very useful and simple enough to use.

Dave
 
Nice work! CAD is an indispensible tool in my shop, even the simplest jobs. I've been a TurboCAD user (2D only) for over 10 yrs....the older free versions and a newer version bought for less than $20 online.

I have of couple questions about Alibre:

1) Did the program generate the isometric view for you after you drew the top & side views?

2) When you say free, do you mean FREE as in a no cost, unlimited use, less capable version? I only do simple plans and have no need for photo-realistic renderings.

3) Can Alibre save your drawings as standard .dxf files?

Thanks,
Milton
 
DICKEYBIRD said:
Nice work! CAD is an indispensible tool in my shop, even the simplest jobs. I've been a TurboCAD user (2D only) for over 10 yrs....the older free versions and a newer version bought for less than $20 online.

I have of couple questions about Alibre:

1) Did the program generate the isometric view for you after you drew the top & side views?

2) When you say free, do you mean FREE as in a no cost, unlimited use, less capable version? I only do simple plans and have no need for photo-realistic renderings.

3) Can Alibre save your drawings as standard .dxf files?

Thanks,
Milton

1) You create the item in 3D and then create the 2D drawing from that

2) For the first 30 days you get all the bells and whistle then after that some of the more fancy parts get turned off but after the 30 days it should still be fine for me and yes its completely free unless you want all the bells and whistles

3)Pretty sure you can export to DXF
 
Thanks! The .dxf thing is important to me. I need .dxf's for conversion to G-Code for my CNC router. I'll give it a try when I get some spare time.
 
I too have found Alibre easy and fun to use. I have tried other CAD programs out there and just couldn't get them to do what I wanted. There are several good tutorials for Alibre available for free. You might have to be using a paid for version to export in dxf format. I just looked for the option in my free version and couldn't find it, though the help does say it is possible. They definitely try to hook you with the full featured version that you get for the first thirty days. They offer it for half price a lot and if you are a student or university employee you can get it for 90% off (~$150 for the pro version).

Peter
 
I needed something that was mine that I could update.

If you can't update or upgrade, it will become obsolete and then difficult to extract and maintain. That defeats the purpose of using CAD.

I bought my version, full up.
I use it ALOT. I even used it at work!

Great package for the money.

Dave
 
pmerritt said:
They offer it for half price a lot and if you are a student or university employee you can get it for 90% off (~$150 for the pro version).

Peter

Gee for $150 I would be happy to buy the pro version but for what I will use it the full price (and half price) is just way too much for me.
 
I worked for 33 years on a drafting board, as a machine design engineer. About 11 years ago I found that I was no longer marketable, and even though I was terrified of computers, (I was 51 years old, and had never used one) I went back to college and learned Autocad 2D, and bought a "state of the art" computer. I found autocad 2D fairly straightforeward, because it was the drafting board all over again---just input lines, arcs, and circles. I worked with Autocad 2D for 3 years, and then found, much to my dismay that the market perception was now changing to "If a person can't design my machinery in 3D with full parametrics and associativity, they must not be very good!!!"---so---Coughed up about $6000 for solidworks and another $3000 for a computer big enough to run it, and went for the training courses that were included in that price. I love the software, and I work in Solidworks exclusively now. Heck, I even teach 3D modelling. It costs me about $1800 a year for my upgrade and software liscence, ut at least I can write it off as a business expense. If ya want to see some neat stuff, have a look at the models in the portfolio section of my web page. www.rupnowdesign.com ---Brian
 
I agree, even half price is too much. This is after all just another toy! I am considering taking advantage of the educational discount. I just hope they don't care that I'm a biologist with no need for CAD!

Peter
 
[size=10pt][size=10pt]Cad rules. [/size] [/size]

Reason to go 3D

1 it's more fun than 2D

2 you make your virtual parts and the software does the boring bits like making drawings and does it faster and more accurately

3 you can see what your designing/drawing so it has a "presents" that you can't get with 2D

4 you can fit the parts together in assemblies to "see" if they will work (first three drawings)

5 shows you that machining might be a real ***** before you start and not after you have invested a lot of time (last 2 drawings)

6 many stock parts such as gears, shafts, nuts and bolts, chains and sprockets, gearboxes etc. can be downloaded off of the Internet from many sources and added into your assemblies or in the more advanced packages the cad software will generate them for you.

These are "assembly" drawings of the elevating gear for my artillery piece 1/6 scale.
Elavatinggearassembly.jpg


Elavatinggearassembly2-1.jpg


This shows it with the outer bits visibility turned off to show internals. Having the ability to visualize parts is a big advantage over 2D. The gears were downloaded and modified, everything else was drawn "in house"
Elavatinggearassembly3.jpg


the last two are of the breach block and the "how do I make It factor".
breachcopy.jpg


breachcopy3.jpg



I'm strictly an amateur draftsman so be gentle.

No drafting tools where harmed in the making of these drawings.
 
3D is nice but bottom line is who pays ?
If it's your own in your own time and the program is cheap enough or paid for then fine.

If it's a job or a paying customer will he pay the extra to get nice 3D draings as opposed to simple 2D drawings and a finished job?

Most of my work goes out as work with no drawing but I need some form of drawing to work with. Bottom line is I'm paying for the amount of drawing needed.
If I can save an hour using accurate sketches as opposed to full detailed and dimensioned drawings then that's an hour up to me.

It isn't all about money either as you can get carried away with drawings to the extent shop time suffers.

Tomorrow I have to mill some clearance channels on a load of electric motor casings. The drawing consists of an approach line, a curve and a depart line, all in 2D. This file has been saved as a DXF and the CNC mill will read this in add the depth, tool offset and follow the three entities. The shape of the motor casing never existed.

.
 
#D is nice... But it is still hard to print a real 3d object on a 2D piece of paper. I have worked for several companies that build special machines and we did all our CAD in 2D. Only one company that i visited on service calls used 3D. One of the employees at one of my customers worked in teh Nuclear industry and he worked on plants before and after teh transition to 3D. the 3D plant drawings gave better results.

SO - if you are going to build very complex systems then 3D might be to your advantage. If you are used to seeing a 2D drawing and can visualize the 3D object then a 2D CAD package will be just fine.

There is one package out there that seems to be much more affordable that works a lot like AutoCAD - Progecad. Progecad Smart is a free download and handles DWG & DXF files and is missing a few features of the full version which is under $500.00 which is not a bad price for a CAD package. http://www.progesoft.us is the url.
 
I started out on he boards guys, like Brian.

If I don't use 3D at work, Im not employed.

I prefer CAD and 3D for the engineering benefits it brings

I use the options that come with the package I have.

Brians comments about cost are spot on for Solidworks, and I truly love that package. I can't justify it for home though ( I use UG at work....if you think Solidworks is expensive......whooooo boy, are you in for a surprise with UG Try 3 to 4X Solidworks, and IMHO it's not as good as Solidworks)

If your never going to use linear FEA, or create toolpaths, or need an engineering library of standard parts,(nuts bolts screws ballbearings,gears ect)
and will never need to do any dynamic analysis or rendering,and I conceed that most will never need any of these features, Go with an appropriate package.

Best wishes to all,

Dave

 
Hi all,
I have recently purchased a package called ViaCad 2D/3D from PunchCad ( website http://www.punchcad.com/products/viacad2d3d.htm )
It cost $99, and I have found after a bit of time learning to use it that it is excellent for model engineers. It imports and exports a variety of formats, can create 3-view engineering drawings from a 3D model, and can handle assemblies by putting each part on its own layer. It can also do basic analysis stuff like determining volume, mass, moments of inertia, and a few other things. It does not yet do motion, but there is an upgrade path to a dearer package which will do this.
There is an excellent website support, and an extremely helpful users forum, which is read by the team which writes the software, and they actually respond to user input.
All in all, I am very impressed with it. It seems to do 60-80% of what packages like solidworks can do, for way less cost.
If I can work out how to do so, I will post a couple of my early efforts; it might take me a few days, so don't hold your breath!
Regards, Ian.
 
I forgot to mention the principal reason for my choosing this package - as well as running on PCs, it also runs seamlessly on Macs, one of which I drive. This is the first package (other than GibbsCam, which costs a bomb!) that I have found which allows me draw the things in which I am interested on a Mac.
I also forgot to mention google sketchup, which is free, and seems capable of producing drawings suitable for model engineers, but I have not used it myself. I have only looked briefly at the website; http://sketchup.google.com/ It also runs on both PCs and Macs
Regards, Ian. :)
 
I have tried to do the free thingy with Alibre. Is there anyone out there more in tune with computers thanI am before I just give up on this? I have downloaded the software and tried to install it several times but I keep getting this message..

Can't even load an image now!!!!

It says "Unable to start the application - The Java virtual machine cannot be loaded. Class not registered.

Sometimes I wish I hadn't started some things!
 
Yes as Twinsquirrel says.
You need to install some other software first but don't worry its only a small download compared to the CAD software
 

Latest posts

Back
Top