----- Original Message -----
Sent: Wednesday, March 17, 2004 8:12
AM
Subject: [PSUBS-MAILIST] thru hull
stress
OK, I'm having a thru hull stress out.
I've learned so much in the past year
I've been with this group and I would like to thank everybody. This is
an incredible group of people. The core group who started this
forum along with everybody else have really enriched my life
measurably!! Just wanted to make sure I said that if I
haven't said it before. I've learned to operate the lathe and mill
along with many other skills of measuring and so forth. And as an added
benefit as well is that I have the whole new area of machining to
talk to my Father about. He was/is a hydraulics engineer, we have always
talked tech but now there is an added dimension to it.
I'm still learning however, it's amazing to me how
when you jump into something how you encounter the problems head on,
something your not going to get working on Auto Cad!! I am still
not entirely clear on this thru hull assembly that I'm trying to do. I
machined this part but now it is becoming apparent that I should have first
obtained a standard "O" ring and made the shaft based on the size of the
"O" ring that is off the shelf so I'm not fighting correct tolerance
problems. The other thing I'm in a quandery about is the fact that the
"O" ring needs about 10 thousanths space between the shaft and the hole.
It seems to me that this is going to create a bit of slop when turning the
valve handle once the thru hull is in place, hence the need for a concentric
larger diameter shaft with closer tolerance that does not have an "o" ring. or
maybe reduce that diameter just near the "o" ring. Also the fitting
or female part where the shaft goes into needs to have a rounded or tapered
hole so the "o" ring does not tear when being inserted into the hole.
And I'm not sure how long I should make the part, how much it should protrude
on each side of the 1/4" hull.
Anyone have some thoughts on some of my quanderies?
What I might do is proceed with what I think is right and then put up a
picture of what I've got and get some reaction from the group. Thanks
all !!
Brian "stress-out" Cox