Making Fibre Feedthroughs

Making fibre feedthroughs for cryostats

• • Take flange with fine holes drilled (typically 250 um jacketed fibre e.g. thorlabs 1310 HD)

  • Measure out lengths of fibre on bench (~2m), marking each end with permanent marker (e.g. one red dash), a tip is not to mark them too close to the end of the fibres

  • clean feedthrough with air gun/isopropanol

  • mount on clamp (outside of flange facing up).

  • thread clean fibre through holes (air gun/isopropanol)

  • mix epoxy in disposable beaker or glass slide

CURRENT Stycast 2850 FT with 23LV catalyst - in chemical cupboard in front lab 222b

Mix ratio 100 parts 2850 FT to 23LV

100:7.5 by weight

100:17.5 by volume

file:///C:/Users/QSG/Downloads/2850FT%20w_Catalyst%2023LV.pdf

Setting time 60 mins

OLD Stycast 2850 FT with 24 LV catalyst - in chemical cupboard in front lab 222b - see lab chemicals

http://lartpc-docdb.fnal.gov/0000/000062/001/Stycast%202850%20FT.pdf

Mix ratio per 100 parts 2850 FT - by weight 4 parts 24LV catalyst, by volume 17.5 parts catalyst.

Setting time 30 mins

Keep beaker/slide to check setting.

Can be made less viscous by gentle heating (useful for flxing small leaks when pumping on vacuum system.)

• • Heat cure with heat gun.

  • Leak test feedthrough mounted to cryostat. (leak checker available from JWNC)

  • Make breakout box/bellows to protect fiber - suitable black boxes in 222b

RHH 29/9/15