Drill Size Incorrect for Tap Size 4

Could anybody link me to a site that may be able to fix the drill size callout problem. I have lived with this for 2 versions now and was hoping that when you invest good money in SW they could get drill sizes correct. (Basic Tap Sizing from a STARRETT drill chart) Examples the 1/4"NC and 8-32 give incorrect drill sizes. Is this a setting problem? I shouldn't have to modify operating files of the system to get this to display correctly?(callout.txt)


TTFN
Captain-Caveman

 

[CorBlimeyLimey]

No problems on my SW2004 system.

1/4"-20 gives Ø.201"
#8-32 gives Ø.136"

Both match Cleveland & Unbrako Tap Drill Charts.




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[mncad]

corblimey,

I guess I'm in between the 2 of you, I know the decimal size is right, but I would like to see SW give the number or letter size of the drill instead of the 3 place decimal. I know this usually gets everyone started on drafting standards, whats right, whats wrong, what a machinist needs, but it comes down to it that our prints have shown the number or letter drill for a long time and the guys in our shop like that.

mncad

 

[Heckdogg]

No problems here on SW2005, also gives you:

1/4"-20 = Ø.201"
#8-32 = Ø.136"

everything matches the charts listed in Machinery's Handbook

 

[drawoh]

captaincaveman747,

Look in the Machinery's Handbook. They vary the tap drill size with the depth of the hole. I would not be sure the machinist does not vary it with the material.

This was discussed at length in thread559-86931.

JHG

 

[captaincaveman747]

I looked a little more into it and what I have found is the actual drill size is correct as you guys have stated.
(.136" for 8-32) but to get to this I have to change the individual properties of the callout to decimal @ 3places.
I work at a welding/fabrication shop and everything is deemed inches usually toleranced to 1/32". Anymore would be a waste of time. We are not building aircraft components here-(Depth to drill size variation has no bearing.) Maybe it is something that can be set in the template or defaults so it reads #29 drill for an 8-32 tap.
It seems to me the callout is driven by the linear drawing unit default of the drawing.-(1/32") in my case. That is why the drill size rounds down to a callout of 1/8"
RSVP / TTFN
Captain-Caveman

 

[TheTick]

Drill sizes can vary depending on material, thread type, thread fit, and various other factors. No way would SW come up with a "one standard fits all" scheme.

 

[aamoroso]

Could anybody link me to a site that may be able to fix the drill size callout problem. I have lived with this for 2 versions now and was hoping that when you invest good money in SW they could get drill sizes correct. (Basic Tap Sizing from a STARRETT drill chart) Examples the 1/4"NC and 8-32 give incorrect drill sizes. Is this a setting problem? I shouldn't have to modify operating files of the system to get this to display correctly?(callout.txt)Could someone email or post a txt file with this taken care of?

Giving a specific drill size is a work instruction not a quality requirement of the part. The Drawing should state the requirements of the part. I am sure the guys in the shop like it but I am also sure they would like it if you glued the correct drill to the drawing. The problem with stating a specific Drill is that you are creating an assumption that you know what type of tap is going to be used, roll taps for instance may require a different drill size. You can achieve a 1/4-20 thread with a variety of tools, if the 1/4-20 thread is the requirement that is all that needs to be and all that should be stated on the drawing.

In closing to answer your questions, you did pay good money for something that does work properly, it does not work the way you wish it too but it does work properly by industry standards. If you can modify a system file to add the custom non-standard information you wish then all the more power to you and good for SolidWorks for giving you the opportunity to do it.

 

[engAlright]

Some annoying things on hole callouts further to what captainCaveman mentioned:

-tap drill sizes default to document units so if you've got a metric tap on a fractional imperial drawing, your tap drill will be in imperial fractions

-drill depth does not always show "Thru All" when it should - even when you define the hole wizard hole as though all, sometimes the drill depth still comes up with a value

 

[captaincaveman747]

I am still at a miss with this. There are many good suggestions above but my point is not being shown. Solidworks and I are in agreement. For the 8-32 tap SW is showing me .136" when I manually change over the unit properties. This is what the software is sizing it at when I am using the hole wizard, and 9 out of 10 tap drill charts will agree with this. What I believe I am seeing now is that the Autolabel function seems to be driven by the linear units default setting in your drawing template. To me this should be handled separately. If it can't show the (fraction or drill size) instead of rounding off to dimesional units (template),then please find me an option to get rid of it all together so the production staff doesn't keep reminding that the callouts on drawings are showing the wrong drill size.-Not because of actual decimal size but because of a roundoff error. I am tired of telling them it is the software, and I should not have to change every callout manually to decimal form to correct the roundoff error.
I can remember using Cadkey Version7 and they had it working right back then. If I can get the software to not even show the drill size I would be happy with that.
ttfn
CaptainCaveman

 

[CorBlimeyLimey]

When creating the holes with the wizard, you have the option of selecting the type of cosmetic thread. Select Add cosmetic thread without callout.


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[captaincaveman747]

Tried that but that has no bearing on it. The second reply to this thread from mncad (Industrial) has said and agreed to what I have been trying to convey.
ttfn,
CaptainCaveman

 

[aamoroso]

I see your pain and the simple most answer is to edit the callouts when you create them to be specific to your companies standard. Alternatively you can probably write a macro that would would search drawings for Hole Callouts and change the note automatically but that is a pretty advanced macro.

The option to get rid of the drill callout:

The default formats for the Hole Wizard types are stored in installation directory\lang\<language>\calloutformat.txt. A second file, calloutformat_2.txt, is a simplified version this one does not put the drill size in a tapped hole note. You can edit either file. If you want to use the second file, you must rename the file to calloutformat.txt, which is the file name the SolidWorks software references so first rename the original to retain it.

You can set the location of the default folder for Hole Callout Format File in Tools, Options, System Options, File Locations.

 

[MElam]

If you model the parts to even fractions, you should be able to set the drawing template units to fraction but uncheck "round to nearest fraction". Then anything that does not hit your set denominator exactly will show in decimals (and the drill sizes usually do not).

If that does not work, select the callout and go to it's properties. Uncheck "use document's units" and then select the units... button right above.


These options should solve the rounding error.

 

[EEnd]

There is a file that defines the hole callouts which you can edit to remove the reference to the drill diameter on tapped holes. On my system the file is:

C:\Program Files\SolidWorks\lang\english\calloutformat.txt

A macro could probably be written to scan a drawing and set the drill sizes to three decimal places. A more aggressive project would be to replace the dimension with a drill number or letter.

 

[captaincaveman747]

Thanks for the info guys (aamoroso & MElam).I am going to use the switchover of the calloutformat files so the drill size will not be shown. Our production staff is competent enough that they know their drill letters/sizes as they use them numerous times a day.MElam found the check mark that I was looking for earlier.(round off to nearest fraction).Thanks again and hopefully SW could set a few more check marks to allow drill letter/size information to be displayed.(Personal wish.)
TTFN
CaptainCaveman

 

[CorBlimeyLimey]

Thanks again and hopefully SW could set a few more check marks to allow drill letter/size information to be displayed.(Personal wish.)

Don't just hope & wish ... submit an Enhancement Request ... that's the only way things will get changed.


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