Submariner1
Member
- Messages
- 194
- Location
- Berkshire
I need to point a right angle Elbow bend in a specific direction (to replace the std. drain valve).
I want a mechanical lock-up, so I can use Loctite 577. I SPECIFICALLY do not want to use PTFE tape, or the Loctite 55 cord. (Because its in a chain of 8 joints, that if one were faulty, would mean undoing them one after the other, grovelling under the tank. Other issue is I end up with 10mm ground clearance, that gets smaller as you lift the front handle. Seriously dumb designer, for not putting on bigger wheels ( er as a spare part they cost £120 plus delivery! Ouch!)
As per the photo below, I initially assumed that I could use a parallel nipple and just shorten it.
Discovered quickly that is not the case. So I then assumed, that the point of “lock-up“ was determined by where the thread starts i.e. at 12 O‘clock or 3.00 O'clock etc. ....So Wrong!
It seems to be a function of where the thread starts in the “female” joint only. I deduced this because different fittings lock up at different directions.
But is this correct? But that Seems very odd.
e.g. the bugger locked up in the wrong direction 180 degrees out. So I assumed if I ground down 1/2 a thread pitch it would alter the direction.
Blow me over, it still locked -up at exactly the same direction?? Tried it again by grinding down say 1/4 of a thread ( admittedly guessing ) same thing!
Yes by grinding down the face if the female thread on the 90 deg. Bend, that alters the direction. I.e. one can turn it a bit more before lock-up.
I would rather not grind down the fitting faces, as its easier to do the nipple, and doesn’t weaken the fitting.
So my question is :- Am I right, that one can not change the direction of a fitting by grinding down the parallel Nipple say x % of the pitch, or was I just very unlucky, when I re-ground them in my trial, and by Sods Law coincidentally ended up with the exact length (thread start point) needed to deliver the same direction?
What I can’t get my head around, is the fact grinding the face of the female fitting works, yet changing the point the thread starts on the Nipple does not. Surely they achieve the same thing?
Its now, not so much a question of doing the job, but am I being seriously thick, and am missing a glaring mechanical principle.
can you explain this?
Note I am not over-thinking this, and have bought a variety of bushes (parallel and tapered), and tapered elbows etc.
Tapered elbows or fitting add a few more mm ... all eating into a miniscule ground clearance. The smallest, is by using a parallel nipple and a female fitting. So that the female fitting butts up exactly to the tank female.
I want a mechanical lock-up, so I can use Loctite 577. I SPECIFICALLY do not want to use PTFE tape, or the Loctite 55 cord. (Because its in a chain of 8 joints, that if one were faulty, would mean undoing them one after the other, grovelling under the tank. Other issue is I end up with 10mm ground clearance, that gets smaller as you lift the front handle. Seriously dumb designer, for not putting on bigger wheels ( er as a spare part they cost £120 plus delivery! Ouch!)
As per the photo below, I initially assumed that I could use a parallel nipple and just shorten it.
Discovered quickly that is not the case. So I then assumed, that the point of “lock-up“ was determined by where the thread starts i.e. at 12 O‘clock or 3.00 O'clock etc. ....So Wrong!
It seems to be a function of where the thread starts in the “female” joint only. I deduced this because different fittings lock up at different directions.
But is this correct? But that Seems very odd.
e.g. the bugger locked up in the wrong direction 180 degrees out. So I assumed if I ground down 1/2 a thread pitch it would alter the direction.
Blow me over, it still locked -up at exactly the same direction?? Tried it again by grinding down say 1/4 of a thread ( admittedly guessing ) same thing!
Yes by grinding down the face if the female thread on the 90 deg. Bend, that alters the direction. I.e. one can turn it a bit more before lock-up.
I would rather not grind down the fitting faces, as its easier to do the nipple, and doesn’t weaken the fitting.
So my question is :- Am I right, that one can not change the direction of a fitting by grinding down the parallel Nipple say x % of the pitch, or was I just very unlucky, when I re-ground them in my trial, and by Sods Law coincidentally ended up with the exact length (thread start point) needed to deliver the same direction?
What I can’t get my head around, is the fact grinding the face of the female fitting works, yet changing the point the thread starts on the Nipple does not. Surely they achieve the same thing?
Its now, not so much a question of doing the job, but am I being seriously thick, and am missing a glaring mechanical principle.
can you explain this?
Note I am not over-thinking this, and have bought a variety of bushes (parallel and tapered), and tapered elbows etc.
Tapered elbows or fitting add a few more mm ... all eating into a miniscule ground clearance. The smallest, is by using a parallel nipple and a female fitting. So that the female fitting butts up exactly to the tank female.
