Am I building threads right? Also do you have a link to thread info that you use?

[Tapap]

So im wanting to make correct threads. My example is 5/16-18 threads. what ive been doing I found information on inner and outer thread diameter for the bolt. I set the outer circle to 0.3113". my inner dia is 0.2454". for a small reference i do (0.3113-0.2452)/2=0.03305" This tells me how deep the thread is from the top. The spacing I just figured its 18 tpi so i made a line thats 1/18". for the helix i did 1/18 and rounded up to 0.056" because if i just did 1/18 it wouldnt work

can you tell me what you think of this file?

also here is here I got my info from, do you have something better?

https://amesweb.info/Screws/unc-thread-chart.aspx

 

[HaroldL]

Here is a link to a crib sheet for creating threads that I put in the Resources section. That may help or at least give another method for thread creation.

Crib Sheet and Data for Basic Thread Form to Create Helical Threads

I zipped together the crib sheet that I previously posted in the Tutorials and Tips from the Community section along with some spread sheets of data for the profile size. The thread data was gleaned from the Fastener Black Book and includes...

www.alibre.com

 

[OTE_TheMissile]

The spacing I just figured its 18 tpi so i made a line thats 1/18". for the helix i did 1/18 and rounded up to 0.056" because if i just did 1/18 it wouldnt work

I've never cared to look into why (at least beyond "too many numbers flying around") but yeah, when doing helixes Alibre doesn't seem to like it if the helix pitch is the same as the width of your Sketch. I'm sure I've made it work before so there is a way, but I don't do helical features enough to warrant investigating it.

Only thing I'd suggest is if you're going to fudge something, fudge the Sketch rather than the helical feature pitch. IMHO, better the thread form be slightly off than the pitch of the thread you're trying to make. Were it being made into an actual part based on your model, that difference in pitch could theoretically lead to problems if the part being threaded is long enough.

Recently pulled most of my hair out over trying to match an imported metric part that had a 1.1mm thread pitch that was short enough that it easily fit my 1mm thread gage.

 

[Tapap]

Here is a link to a crib sheet for creating threads that I put in the Resources section. That may help or at least give another method for thread creation.

Crib Sheet and Data for Basic Thread Form to Create Helical Threads

I zipped together the crib sheet that I previously posted in the Tutorials and Tips from the Community section along with some spread sheets of data for the profile size. The thread data was gleaned from the Fastener Black Book and includes...

www.alibre.com

thanks that made a lot of sense.

 

[Tapap]

I've never cared to look into why (at least beyond "too many numbers flying around") but yeah, when doing helixes Alibre doesn't seem to like it if the helix pitch is the same as the width of your Sketch. I'm sure I've made it work before so there is a way, but I don't do helical features enough to warrant investigating it.

Only thing I'd suggest is if you're going to fudge something, fudge the Sketch rather than the helical feature pitch. IMHO, better the thread form be slightly off than the pitch of the thread you're trying to make. Were it being made into an actual part based on your model, that difference in pitch could theoretically lead to problems if the part being threaded is long enough.

Recently pulled most of my hair out over trying to match an imported metric part that had a 1.1mm thread pitch that was short enough that it easily fit my 1mm thread gage.

thanks for the tip. yea i was tweaking the pitch. i dropped the thread size by 0.001 and left the pitch alone so now its smooth as butter

 

[Tapap]

i just found this in C:\ProgramData\Alibre Design\System Files\Threads

alibre continues to surprise me. im going to try to build a thread generator that will model the threads this summer with a script. or at the least make a selection box and itll draw the thread based on your selection and you just constrain it somewhere

 

[albie0803]

Unfortunately, helical boss and cut are not yet available in AlibreScript, neither is circular or rectangular pattern.