>1) What types of thermocouples are you currently using?
>
>2) If standard wire (Type K), what gage wire?
>
>3) If standard wire, do you buy preassembled or 'roll your own'?

We spark weld our own (type K) using 3thou PTFE insulated wire.

>4) What is your method of attachment for profiling?
>        (solder/glue/tape/other)

These days we tend to use chipbonder cured with a heat gun - quick
and simple.

>5) What specific material/mfr/part #?
>
>6) Do you use a fully loaded board for profiling?
>
>7) How often do you get to use a fully loaded board?
>
>8) Do you keep the board, with thermocouples attached, for later
>oven/profile validations?
>
>9) Do you use a partially loaded board with only large mass parts?

Being a research/education establishment, rather than production, we
tend to have test boards made for specific trials, which we sometimes
keep for a while with thermocouples, or for teaching we use partially
loaded boards (to save time/cost) with samples of a range of component
sizes, which we dispose of when the class has finished.

>10) Do you use a bare board only?

Sometimes to make our experiments simpler (see 11).

>11) What are your main concerns when profiling?

We tend to be gathering data e.g. to compare with models or for testing
advanced oven control technologies, so accuracy of the data and ability
to transfer into other software (e.g spreadsheets) is vital.

>12) Have you previously used other methods of attachment?
>
>13) If so, what type?
>
>14) What were your results?

We have used high temperature epoxies, which while more able to cope with
repeated reflow cycles than chip-bonder, tend to have much longer cure
cycles. We have also used "tak-pak", but this cannot stand more than a
couple of reflow cycles. The main limitation of high temp solder is that
we can't use it to attach to component packages of the PCB surface and
with the fine wire thermocouples that we use the accuracy is OK with glue.

>15) Do you work for a contract assembler or an OEM?

No.

David Whalley
Loughborough University

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