【转帖】countersink callou

yang686526

countersink callout
i have a customer drawing with a counterisnk callout that uses 'vd' after the dimension. what does 'vd' mean?
thanks
eng-tips forums is member supported.
is it an actual letter "v", or the v-shaped symbol sometimes used for countersinks?
does the value of the dimensin correspond more closely to a diameter or to a depth?
the callout is as follows:
"90潞 c'sink to *.28-vd" (* = diameter symbol)
quite clearly a letter 'v' and not the angle symbol. so they give the angle and the diameter and then add "-vd"
weird, huh?
i'm stumped - the old books say that 'vd' = van dyke!
is this hole going into a flat surface?  if not, could it mean "variable depth"?
good guess...but there are many chamfers and countersinks on this part both on flat and non-flat surfaces. and they all have '-vd' after the diameter.
i think it means the "v" diameter (the diameter at the top of the angle). which is not correct. a 90潞 c'sink can not be controlled by the .28 tol.
chris
systems analyst, i.s.
solidworks/pdmworks 05
autocad 05
that's confusing. any diameter countersink can be controlled by the diameter dimension - that's the way it is done. i have no questions about that aspect. i just want to know what vd stands for. how do you measure a countersink, chris?
you can dim c'sink by depth/angle, angle/dia or depth/dia (not preferred).
chris
systems analyst, i.s.
solidworks/pdmworks 05
autocad 05
it may be that your customer did not know how to input the countersink symbol, so he used a v instead, and the d could be for diameter.
previous standards
?.25 thru
c'sink 82
to .50 dia
asme y 14.5-1994 standards
?.25
∨? .50 x 82°
flores
if your customer can't explain it, you might just as well disregard the vd and take it as a standard countersink. if they find fault with it, the burden is on them to show otherwise.
the buyer just responded:
she says that  guy went out in the shop and asked. she was told that it stood for "visuallu dull" as in break edges.
think someone's pulling her leg? i do.