Screws for Metabones smart adapter mark v Canon mount

Started 3 months ago | Discussions thread
MOD Tom Caldwell Forum Pro • Posts: 41,931
Re: Screws for Metabones smart adapter mark v Canon mount

VLreviews wrote:

Tom Caldwell wrote:

I think that Ernsts M4 is probably correct - my vernier calipers said 3.8mm - but I might have had them over-tight when measuring. There is no doubt that the “HUA 10.9” refers to the actual screw thread length (add the countersunk head).

No, the 10.9 refers to the strength class: https://en.wikipedia.org/wiki/Screw#Mechanical_classifications

With your measures, this is most likely a custom M4 machine screw with length 13.5. In that case, an M4x13 should fit fine. The more typical strength class is 8.8, so you might need to search a bit for one in 10.9 (higher strength).

Thanks for that - appreciated.  The actual thread only length (portion) I measured was 10.9mm - it must have been the co-incidence that guided me ...  It did surprise a little as it did not include the depth of the countersunk screw head.

The strength necessary is presumably because of the potential size of the lens that could be mounted on the adapter.

This is worth a further comment. All reasonable lenses that I might need to mount on a tripod when used with this adapter have their own made for purpose tripod mount foot.

So with my Metabones adapters I have removed the tripod mount part but kept the part and components in their supplied box in a plastic bag to try and ensure that I also don’t lose the parts.  There could be a necessity to use the adapter for a lens without its own tripod foot in which case I would re-attach mine. My components are not lost.

These remarks beg the question regarding the need for higher strength screws.  Metabones <<has>> to be able to build to contain the largest lens that any user could possibly fit.  However it would be up to the actual user to decide if they might take the risk with a lower strength screw based on their expected need.

-- hide signature --

Tom Caldwell

Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow