Custom Threading XML - Pitch is wrong

[Anonymous]

Hello,

Similar to my other post where I specifically called out issues with ThreadType, I am also noticing issues with Thread Pitch.

I followed this tutorial: https://knowledge.autodesk.com/support/fusion-360/troubleshooting/caas/sfdcarticles/sfdcarticles/Cus...

My XML:

<ThreadType>
	<Name>Test Custom Thread</Name>
	<CustomName>Test Custom Thread</CustomName>
	<Unit>in</Unit>
	<Angle>60</Angle>
	<ThreadForm>1</ThreadForm>
	<SortOrder>1</SortOrder>
	<ThreadSize>
		<Size>2.20-A</Size>
		<Designation>
			<ThreadDesignation>TestThread</ThreadDesignation>
			<CTD>TestThread</CTD>
			<TPI>6.62</TPI>
			
			<Thread>
				<Gender>internal</Gender>
				<Class>2B</Class>
				<MajorDia>2.221</MajorDia>
				<PitchDia>2.149</PitchDia>
				<MinorDia>2.075</MinorDia>
				<TapDrill>2.048</TapDrill>
			</Thread>
		</Designation>
	</ThreadSize>
	
</ThreadType>

As you can see I am looking for a thread pitch of ~0.151 inches (1/0.151 = ~6.62 TPI). What I get is 0.167 pitch or ~6 TPI. Why?

Files attached to replicate issue. I am on Windows 10 running Fusion 2.0.8407.

[HughesTooling]

@denyerec Did you look through this thread? It seems like you need to set the thread type to 8 for whitworth form now.

Also have you seen the custom thread utility here?

[denyerec]

Nope i completely missed that one - including the TheadForm parameter , thankyou! I didn't see that appear in the BSP file, so I just added my own declarations to that and moved on (As they construct with the correct form in that case) - I shall go and take another look at it and rewrite a separate fileset as hacking one of the included files is tedious with the way Fusion now occupies a different folder every 3 days! 🙂

[HughesTooling]

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@denyerec wrote:

Nope i completely missed that one - including the TheadForm parameter , thankyou! I didn't see that appear in the BSP file,

To make creating custom thread files a bit more confusing, the standard XML files that come with Fusion seem to be hard coded for the form. So if you copy the standard files and rename, the whitworth form versions don't create the correct form unless you add the ThreadForm parameter.