topic Re: US Paint or Broom Stick Thread Type? in Fusion Design, Validate & Document Forum

US Paint or Broom Stick Thread Type?

Anonymous — Sat, 09 Jan 2016 16:55:31 GMT

I've searched for the above subject matter, but found nothing. I'm not an engeneer, and I'm sure that's the problem

Problem:

I'm trying to 3D print a widget, and need to create a hole with a thread type for a standard Paint Stick. I thought that most US Paint Stick threads were ACME, 4 or 5 theads per inch.

However that doesn't seem to be the case. Every paint and broom stick I own will not work with the ACME thread type, I've tried 2,3, and 4G but no luck.

Question:

I was hoping that someone might know which thread type I use in Fusion 360 for the above subject?

Picture below may help...

Re: US Paint or Broom Stick Thread Type?

PhilProcarioJr — Sat, 09 Jan 2016 17:24:36 GMT

A few months ago I had this same issue and found a post on www.practicalmachinist.com/ that helped me a lot.

There is no standard so......most fit this description.

SeymourDumore posted:

"Bout 6 months ago I went through this nightmare of a special project of making a quite intricate device to fit on the end of a plain ol' broomstick handle. Customer had no idea what the handle was going to be made out of, but he absolutely needed that interface.
I can tell you that after testing approximately 20 different makes and models of female devices ( brooms, pushbrooms, cheap paintrollers, expensive paintrollers, polesanders, brushes and you name it ) by far the most were the closest to a 3/4-5 ACME.
The only problem was that using the ACME thread specs, they did not tighten up. My app was 1" deep blind hole, so imagine the chip issue.
Nonetheless, what I came up with was to reduce the major dia by .03 and give it a 5 degree taper.
Since the handles are made of all kinds of garbage using all kinds of garbage specs ( if any ), the taper had allowed something ( and I could not care less what part of ) the thread to lock up and tighten.
Anyway, this was my experience with the broomstick female thread. Straight bore, .02 under spec for the major and a 5 deg. taper.
If this is an internal application, I've found Micro100 the only supplier of a tool which can fit inside the bore and create the thread. Found no taps or threadmills to make a blind 3/4-5 ACME."

0.7500-5-ACME-4G
Allowance,--
Minor Diameter Min,0.5500
Minor Diameter Max,0.5600
Pitch Diameter Min,0.6500
Pitch Diameter Max,0.6562
Major Diameter Min,0.7700
Major Diameter Max (Ref),0.7900
Flat At Root,0.0690
Thread Height (Basic),0.1100

Pitch,0.2000
Lead,0.2000
Starts,1
Lead Angle,5.624

Hope this helps some....

Re: US Paint or Broom Stick Thread Type?

Anonymous — Sat, 09 Jan 2016 17:24:53 GMT

That's about what I've been through, but unfortunately don't have the technical knowledge or experience to know how to do this in my model. There doesn't seem to be any way to really adjust the ACME thread settings to any real degree, so that leaves me in a weak position.

Any help would be much appreciated.

Re: US Paint or Broom Stick Thread Type?

PhilProcarioJr — Sat, 09 Jan 2016 17:35:49 GMT

You might have to create the threads manually using a sweep with a custom cut profile.

You can create the helix using the method in this thread then use the thread specs along with his suggestions to make a custom cut profile.

helix-spline-in-fusion-360

I will try to do some screen caps of the steps soon but my time this weekend is very limited so...

Re: US Paint or Broom Stick Thread Type?

tobycwood — Thu, 18 May 2023 19:23:04 GMT

This has been an ongoing problem with Fusion360 for years and its starting to look like they really do not care about actually fixing it. What is the big deal? Simply give us the settings in the thread tool for an ACME thread that will actually fit the standard thread on a broom handle! Why is that so hard?

Because of this neglected problem I refuse to spend one penny on a Fusion360 license and instead produce tool designs using a different CAD.