Rework and stringing problem solving page
- Name: Kirill
- Synopsis: A high results of tension measurement during wire
replacing.
- Date: Tuesday, July 22, 2003
- Time: 09:42
Description
If we have a too high results of first tension measurement during wire replacing, we need be sure what the spool break lever doesn't touch of plastic screw.
- Name: fred luehring
- Synopsis: DIO error - 10401
- Date: Friday, April 25, 2003
- Time: 07:55
Description
Today stringing station #3 - the new IBM laptop (ATLASPC32) had a tension
program failure. The error message was "DI0 Error -10401". This error both
stopped the program from working correctly and also left the HV on the
chamber. After several tests, I was able to solve the problem by rebooting the
computer. So if you encounter this error with this computer (i.e. stringing
station 3), please go ahead and reboot the computer and report that happened
to me (email is fine). Important: Please close the John's database program
before rebooting.
Problem reported on Thu, 31 Oct 2002
- Name: fred luehring
- Synopsis: run time error for tension program
- Date: Friday, April 25, 2003
- Time: 07:57
Description
Alan discovered a small "gotcha" in the tension program. It turns out that
a run-time error will occur if you enter a comment with an apostrophe (') in
it. This is because adding an apostrophe to a comment terminates the comment
before it ends. When I send data to the data base the comment itself is
delimited by apostrophes and the SQL connection becomes confused when a third
comma is added to the string. The bottom line is to not use apostrophes when
writing a comment. If there is a need for a new version of the program, I will
fix this problem but I am not making a special release to fix it.
reported on Nov 4, 2002.
Stringing tips
Gathered from the IU stringing crew in March
2003
- On tension program, select "single or double":
the frequency range and voltages will change
- Back end of the module is placed closest to the reel;
front end near the wire spool;
- frequency cutoff after re-stringing is 128 Hz for single
joints, 125 for doubles;
- orange tension probe goes inside the taper pin; red one on any ground;
- fix the module with 4 Plexiglas clamps in the stand at one end and two
underneath the module in the middle; the end where the speaker is should be
left unconstrained; the Plexiglas clamps should be trimmed to fit if need
be;
- connect the kapton connectors to the fuse box; connect fuse boxes to
distribution box and distribution box to control box;
- if the remote control fails to work, power cycle the main unit.
If the remote control looses its settings and won't work
- press on the "on" key until it flashes
- then press on the on key twice and hold it until it flashes again
- do the same thing with the second on button
To insert a lead wire when it's difficult to get pass the OWS:
- make a tiny hook at the tip of the wire with fine pliers.
It helps to get past the first twister
- if it still won't go: pull back the nozzle, wiggle the
wire a bit, twist it between fingers, pull some back out
If it stops getting through while feeding the lead wire in:
- if a kink appears, make it get past the nozzle by feeding
it by hand for a few cm.
- if it is at the beginning of the lead wire, cut it out to
avoid having to deal with it later on. Pull all the wire through and cut it
before reeling it back in with sense wire.
- if it stops getting in while using the air blower, pull a
fair amount back out and try again;
- after feeding the lead wire, pull back the nozzle out of
the way to ease the reeling
How to fix the sense wire:
- pull enough wire from spool to get the bead past the
middle post;
- attach the wire stretching the clip elastic a bit;
- tension wire by hand, positioning the bead within the slot
of middle post, bead wedged in place on the spool side of the post.
- cut the wire between the pin holder tool and the clip;
- tight the knot no more than 10-15 cm from the clip
to avoid getting the knot stuck in the nozzle on the way back; use handle of
small hand-tool to thread the two strands through the loop.
- unclip the clip closest to the module; take the slack back
with reel on;
- take tool in hand, fix taper pin on and reel wire in;
- stop 2-3 cm from the module; make sure taper pin and
eyelet are in place; align taper pin as straight as possible; drop the
weight and fix the taper pin in place;
- remove tool and cut excess wire; insert the orange tension
measurement probe and red ground; release weight and apply weight again;
- measure tension with weight on; apply second taper pin if
tension is ok; if wire appears to be off-centered, try to fix it (see
below); if tension measurement is poor, release tension, re-apply weight;
see below;
- insert second taper pin in; align the tool as parallel as
possible to the wire; do not cut the wire yet; measure tension;
- release the weight and cut the wire; make the final
tension measurement.
If there is a bad tension reading:
- increase the voltage
- change the frequency range if the peak is close to the
edge
- increase the scanning time
- if tension is bad at the first pin insertion, release
tension, re-apply weight
- to determine if tension measurement is ok, compare
overtone and fundamental; they should be about equal, single sharp peaks, ~
100 in amplitude
- if there are many peaks, the main peaks should be in the
same position
- if tension is too high after the first pin insertion,
release weight, give some slack, re-apply weight and re-measure;
If the wire is off-center: the fundamental gets much broader
and amplitude reaches ~ 600
- try to release the weight, twist wire with fingers;
re-measure tension to see if it is ok;
- release tension, increase scanning time and run a tension
test with no tension on it to try to get the wire to be shaken back into
place; re-tension and test again;
- wiggle wire between fingers with speaker on;
Taper pin is sticking out; wire get cut as soon as taper pin
is being inserted
- try reaming the eyelet to resize it properly; push the
special tool in, applying some pressure and turn it a few times;
Bad twister: joint got stuck as it went in
- Stop the reel; cast and pull it all out;
- start reel again and orient the wire at various angles
until the joint goes through;
- or: pull back 2-3 cm; from the back end; have a second
person twirl it between fingers and then give it a sudden jolt
- the person at the front end simply holds it properly
aligned, about 2-3 cm from eyelet.
Wire got stuck while pulling out
- twirl it between fingers while pulling gently
- push air through the straw and twirl it to get it going
To fish for a wire:
- if lead wire won't get through or a piece of wire is stuck
in a straw, use a fishing wire to go from the front end to fish it out; make
a small hook at the tip or fold a 10-20 cm piece and twirl it before
inserting; twist between finger while pushing it in and retrieve it;
When removing a wire:
- remove taper pin at back end first; double check that
this is the right straw!
- remove taper pin at the front end;
- pull the wire all the way through from the front end; this way, the wire only
goes through one twister (single-joint wires) since the single-joints are in
front of the central wire supports (CWS)
- do the opposite ends for a type 2 module
If an eyelet comes off when removing a taper pin:
- be careful not to loose the taper pin between the tension and HV plates!
- push it back in place and apply some conductive glue;
- a bad eyelet could also give a flat reading on the tension measurement but
no trouble when checking the HV; the 16-channel tension tester would also
give a strange but non-flat spectrum, more like a broad plateau with lots of
wiggles on top in such a case.
Taper pin insertion tool calibration: (taper pin batch # from IU in March
2003: 3754)
- should be set for 8 lbs (3.5 kg-force)
- turn allen screw clockwise to lower tension; CCW to increase tension
- very sensitive screw: 5 degrees ~ 2 lbs-force.
Taper pin insertion tool repair:
- if the central pin breaks loose, glue it back in place with Locktite.
To load lead wire on the reel
- fix it to the reel with a piece of teflon tape using fine tweezers to get
there
- make sure that the tape corners are completely flat
- secure the feeder spool while it goes holding it with one finger
- reel it on with the reel turned on
- some people like to load a lot at a time
-
If a straw fails twice to be restrung, give up!