Here is a sample screw selector

[LewisA]

Watch this and give me your thoughts, please.
http://delta-eng.com/video/CapScrew

 

[DavidJ]

Looks neat to me. Especially since the long promised Intelligent Part Generator was dropped from Geomagic's plans.

I must look at how stuff like this works - so far the Python stuff has gone over my head (even though I have programmed in the past).

 

[Lew_Merrick]

Lewis,

I assume you are unaware that I have posted "libraries" of most common and specialized (inch-size) screws & bolts over at http://www.GrabCAD.com -- these "libraries" come not only with a complete set of part models of the screws & bolts, but also a (LibreOffice Calc) spreadsheet index to provide selection support information such as maximum allowable tensile load, maximum allowable single-shear load, torque to 85% of yield values, and the like.

My argument here is that generating such fasteners on the fly misses things such as the variations in threaded end length, a reference plane to establish the (by the various standards) minimum thread end position, material specification, and the like. My libraries provide a (normally suppressed) reduced shank diameter for the threaded length of the screw or bolt that can be used to eliminate false positives when performing interference checking (and also aid in applying FEA constraints). My libraries of graded screws & bolts also show the markings that identify the specific grade. Etc.

Yes, I now use WizoScript to generate such part libraries. I am a very strong booster of Andy Ayre's efforts along these lines. (I hope to be posting my first efforts at writing "tutorials" for WizoScript here shortly.) Now, having said that, there are limitations to what can be accomplished with WizoScript. Most of such limitations derive more from the limitations of the GMD API than Andy's efforts, but they do exist.

I will further grant you that the description coined by the people at Generic Software in the 1980's (There are the few -- and then there's Lew) still applies. A not insignificant portion of my work has to be completed within government standard specifications (DoD, FAA, NASA, NATO, etc.) which provides a rather severe review qualification on my models and parts lists. (i.e. it cannot be a 1/4-20 thread, it has to be a .2500-20UNC-2A thread -- and the difference between common commercial and formal specification on metric fasteners is even more pronounced.) These are some of the reasons I turn into an OCD type on the subject.

 

[RocketNut]

That looks like what I have been looking for a long time. It sure would make my life easier for sure.

Where can I down load the script? Does the script make different configs for clearance,tap, and bolt shape (I.E. flat or standard heads)?

Rocket Nut

P.S.
I'm also a very strong booster of Andy Ayre's efforts along these line. His Wizo Script has save me untold time in designing like my Segmented Jack Screw. Keep up the great work Andy. You have unlocked the power auto design work.

 

[dammerel]

Great work, nice and easy ..i like it

 

[RocketNut]

I have been working with LewisA on this screw selector program. It's a very powerful tool. What makes it so powerful is it only draws the screws you want or need. Unlike other parts library which waste hard disk space with thousands of screws you will never use. LewisA does not do that because it only draws the screw(s) you need or want.

It's very easy to use. Just start the program. Then you select the the series of the screw you want (right now there is only 1960 an M (mertic)). Now just select the screw you want then either enter or select predefine length of the screw. Then click on build part button (top left corner). Wizo script windows opens up an GM starts. About a sec or two Wizo screen closes. Now you can edit the screw part if need and then you casn save it with the default name or your choice of the file name.

I just know what to say, but it's a very power tool. As I said early it does not load up my hard with parts I will never use.


LLAP

 

[RocketNut]

EDIT # 1
I forgot to mention External Threads. Wizo does not have a command to generate the External Thread's, this means that you will have to add External Threads when the screw/bolt in complete.

LLAP

 

[ajayre]

EDIT # 1
I forgot to mention External Threads. Wizo does not have a command to generate the External Thread's, this means that you will have to add External Threads when the screw/bolt in complete.

LLAP

I could add it, but... there is a bug in GD that stops parts with external cosmetic threads from being saved through the API. Well, there is an error the user has to ack and then the save happens anyway.

Andy

 

[RocketNut]

ajayre
My personal thoughts about External Threads being add to Wizo is no. I feel that there is a API bug that might cause an error, then I would add the external threads by hand. It very easy and only takes a few mouse clicks ( it takes a second or two). Doing by hand I am assured there is no errors.

LLAP
Rocket Nut

 

[Lew_Merrick]

To be clear, the Cosmetic External Thread "bug" opens an error screen that you have to "accept" to dismiss and the Save As works fine thereafter. It falls into the PITA, but not a Problem class of issues.

 

[RocketNut]

Again for me it's just simpler and error free to do the threads by hand after the script is finished.

 

[dammerel]

hi guys
check out an example from the freecad web
freecad is starting to become a usable system


http://www.freecadweb.org/wiki/index.ph ... w_maker1_2

 

[RocketNut]

LewisA is looking for some one using Exel spread sheet to test his screw selector program. I'm using Libre Office an works great with out errors. Please P.M. or email him so he can debug his program.
The program in very easy to use and very intuitive. It has become apart of my tool kit. I have redone over 12 of my bolts (use in several projects/model).

LLAP
Rocket Nut

 

[shmbry]

Lewis,

I assume you are unaware that I have posted "libraries" of most common and specialized (inch-size) screws & bolts over at http://www.GrabCAD.com -- these "libraries" come not only with a complete set of part models of the screws & bolts, but also a (LibreOffice Calc) spreadsheet index to provide selection support information such as maximum allowable tensile load, maximum allowable single-shear load, torque to 85% of yield values, and the like.

My argument here is that generating such fasteners on the fly misses things such as the variations in threaded end length, a reference plane to establish the (by the various standards) minimum thread end position, material specification, and the like. My libraries provide a (normally suppressed) reduced shank diameter for the threaded length of the screw or bolt that can be used to eliminate false positives when performing interference checking (and also aid in applying FEA constraints). My libraries of graded screws & bolts also show the markings that identify the specific grade. Etc.

Yes, I now use WizoScript to generate such part libraries. I am a very strong booster of Andy Ayre's efforts along these lines. (I hope to be posting my first efforts at writing "tutorials" for WizoScript here shortly.) Now, having said that, there are limitations to what can be accomplished with WizoScript. Most of such limitations derive more from the limitations of the GMD API than Andy's efforts, but they do exist.

I will further grant you that the description coined by the people at Generic Software in the 1980's (There are the few -- and then there's Lew) still applies. A not insignificant portion of my work has to be completed within government standard specifications (DoD, FAA, NASA, NATO, etc.) which provides a rather severe review qualification on my models and parts lists. (i.e. it cannot be a 1/4-20 thread, it has to be a .2500-20UNC-2A thread -- and the difference between common commercial and formal specification on metric fasteners is even more pronounced.) These are some of the reasons I turn into an OCD type on the subject.

Please can you tell me where on Grab Cad can these be found ?

 

[HaroldL]

Please can you tell me where on Grab Cad can these be found ?

I think these were uploaded to the Resources section.