Welcome to the Onshape forum! Ask questions and join in the discussions about everything Onshape.

First time visiting? Here are some places to start:
  1. Looking for a certain topic? Check out the categories filter or use Search (upper right).
  2. Need support? Ask a question to our Community Support category.
  3. Please submit support tickets for bugs but you can request improvements in the Product Feedback category.
  4. Be respectful, on topic and if you see a problem, Flag it.

If you would like to contact our Community Manager personally, feel free to send a private message or an email.

Countersink head size for M4.5 is not correct

Fox66Fox66 Member Posts: 4
edited July 2017 in Community Support
I think the numbers provided by the hole wizard are not correct for Countersink ISO Clearance M4.5

Close clearance M4: hole=4.3 head=8.96
Close clearance M4.5: hole=4.8 head=4.8   <--Head size: 7.5?
Close clearance M5: hole=5.3 head=11.2

Normal clearance M4: hole=4.5 head=8.96
Normal clearance M4.5: hole=5 head=5   <--Head size: 7.5?
Normal clearance M5: hole=5.5 head=11.2

Loose clearance M4: hole=4.8 head=8.96
Loose clearance M4.5: hole=5.3 head=5.3   <--Head size: 7.5?
Loose clearance M5: hole=5.8 head=11.2

The tapped and drilled numbers are also wrong.

Best Answer


  • owen_sparksowen_sparks Member, Developers Posts: 2,660 PRO
    edited July 2017
    I had the same issue I believe when I messed about adding sizes to the default feature.  I believe the countersink sizes there are for knocking the edge off the lower face of a counterbore cap-head clearance hole (where the bottom of the head meets the threaded portion of the screw), and  are not for a countersink "head" hole at all.  They're shown in a lot of data tables as "countersink" but have nothing to do with countersink head profiles so it's an easy mistake to make.

    Owen S.
    Business Systems and Configuration Controller
    HWM-Water Ltd
  • owen_sparksowen_sparks Member, Developers Posts: 2,660 PRO
    edited July 2017
    Not sure if @Silver reported this as a bug, and if not if whether an OS dev has read this post?  @lougallo / @philip_thomas are you the right guys to ask? 

    As an example I've just checked and the updated hole command is still bugged as above.  An M4.5 countersunk hole gives a 5mm countersink which is actually the clearance hole size so gives no countersink at all.

    I've not known OS release anything incorrect before, so would have thought it would have been jumped on if they're aware of it.  Making incorrect holes is worse than it not working at all after all.

    Cheers, Owen S.

    Business Systems and Configuration Controller
    HWM-Water Ltd
  • philip_thomasphilip_thomas Member, Moderator, Onshape Employees, Developers Posts: 1,381
    ooops - i will look into this - thank you.
    Philip Thomas - Onshape
  • owen_sparksowen_sparks Member, Developers Posts: 2,660 PRO
    Hi Phillip.

    No worries, OS has built up a pretty hefty bag of good-will so this won't dent it! :)

    If on the other hand you'd care to throw us an extra year's pro subscription for an additional user as a finder's fee I'd not argue :p

    Owen S.
    Business Systems and Configuration Controller
    HWM-Water Ltd
  • PeteYodisPeteYodis Moderator, Onshape Employees Posts: 473
    We are aware of this.  Hole feature generation 1.0 had countersinks that only worked by default with countersunk socket head cap screws and counterbores that work by default with socket head cap screws.  Obviously the world wants to create countersinks and counterbores that work with far more than just these two fastener types.  Hole feature generation 1.0 also only had tapped hole sizes that worked with these fastener types.  There were a lot of user requests to make far more tapped hole sizes available (and rightly so!).  When we released all the new tapped hole sizes last release we had a decision to make on the new sizes where there were not countersunk socket cap screws at these thread sizes available.  We did not want to block users from being able to make countersinks and counterbores for these new sizes, but we also did not have a valid fastener to size to - so we elected to do what you see here as an interim step.  It's not great, but we did not want to block our users.  Currently for these sizes you can make the countersink and counterbore diameter anything you like, so we provided flexibility rather than restriction in the interim.   

    In the future we plan on allowing a fastener type selection after the counterbore and countersunk hole type (along with a recess parameter to ensure the fastener type is to be recessed below the face).  This really provides a far greater level of support in the hole feature than what you see today.  I hope users understand.  We're working to make this a far better area of the product.
Sign In or Register to comment.