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Problem constraining Flat head screws?

I have tried several things to position a flat head screw, but without success. Is there a trick to this?

The top of the screw should be below the surface of the part. The edge between the shoulder and the shank should also be below the "break" edge in the hole. I have thought about the potential of adding a plane but this is still contingent upon how the hole was made.

My first appoach was to attempt to constrain the conical surface under the head to the conical surface in the hole. But, this doesn't seem to work. Is this a bug? Does anyone know if SW is planning to add this as a constrait?

Thanks,

Reply to
Ed
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Make sure that the conical angle of the flathead are the same as the csink. You can then mate the conicals coincident. Another way you could do it is to put a sketch point at the point of the cone on the screw. Then you could mate the point coincident to the csink with a concentric mate of the screw shaft with the hole.

Reply to
j

Rather than making the conicals coincident, I make the circular edge coincident to the countersink. It has the plus side of being able to still mate the screw as it will be in real life even if the angles don't match. On the other hand, you may not notice that the angles don't match.

Another advantage of either way is that it only takes one mate to put the screw in place. Granted, it doesn't constrain it rotationally, but I usually leave those free anyway.

WT

Reply to
Wayne Tiffany

Reply to
That70sTick

I always make the conical surfaces coincident. I had a problem with this once, but it turned out to be user error. I use flat heads with the 82° included angle for the conical surface. However, in the SW hole wizard there are options for the 82° and also for a 100° variety.

When I had problems it was because I had inadvertantly created the hole at

100° and was attempting to mate an 82° fastener to it. That doesn't work.-:)

jk

Reply to
John Kreutzberger

I would add a Primary Mate Reference with a mate reference type of any to conical surface when you drag it into assembly, fastener should snap to a concentric mate with countersunk hole. You do not say what version you are using.Works on 2006 SP4.1. Concentric mate is established regardless of different angles between components. Wayne's suggestion for height positioning is probably the easiest to apply.

The Mate reference box gives the user the opportunity to establish a primary, secondary, tertiary mate all in one shot, but I have never been able to get it to work the way it's descibed in the help subject. Seems to have been half baked/broken now for many releases - sigh.

Neville Williams Z-Axis Design - NZ "remove the KNOT to reply"

Reply to
Nev Williams

Great! Thanks guys!

I checked the angle of the C'sink and when I got it to match with the screw it worked great, and as expected... Always some little trick.

Thanks for the help.

j wrote:

Reply to
Ed

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