505.839.3010
Neutec/Rio Grande™ J-2
r
Rev. F
Page 5-4
Installing the Rod Assembly
1. Place new sealing rod in the holder. Hold the
metal tube with the holder in one hand and
tighten the clamp with a 5mm Allen key.
Please Note: When the sealing rod holder
gets hot, the metal parts expand more than
the sealing rod. Be sure the clamp is well
tightened so the rod will not drop out after
being heated. Do not over-tighten the clamp
because you may break the rod. A good rule
of thumb is to turn the Allen screw until it
starts to offer resistance and then turn it an
additional one-quarter turn.
Tighten the clamp on the sealing rod.
2. Clean the inside of the hood and all sealing
rod parts before re-assembling.
3. Push the sealing rod holder tube up through
the top of the hood and lift the collar as far
as possible.
4. Lightly tighten the collar screw to hold
the sealing rod in the up position. This will
ensure that the sealing rod will not hit the
bottom of the crucible when the hood is put
back on the machine.
5. Re-install the hood on the machine. See
“Adjusting Sealing Rod Tension,” below.
6. Re-install the thermocouple in the sealing
rod and plug it into the machine.
Adjusting Sealing Rod Tension
Good contact and sufficient pressure between
the sealing rod and the crucible prevent molten
metal from leaking. Proper adjustment of the
tension on the sealing rod, described below,
helps prevent leakage.
•
Warning! If the machine has been in use, the
parts involved in this procedure will be hot and
can cause severe burns if you handle them
without protection. Use gloves and other safety
gear to protect yourself.
1. Begin with the crucible in place and the
sealing rod assembly securely clamped in
its holder.
Crucible should be in place and the sealing rod installed.
2. Loosen the sealing rod collar screw on top
of the crucible chamber hood. Hold the steel
tube to prevent it from dropping into the
crucible.
3. Push down lightly on the top of the steel
tube. This will move the whole sealing rod
and ball assembly down.
4. Firmly seat the sealing ball in the bottom
of the crucible.
