Sweets
What if you screw up the nomex item, are you going to replace it.
What if your work somehow compromises the integrity of the garment and that results in an injury to the wearer can you cover the legal fees to protect you a$$?
Would you work on a NASA pressure suit if you could buy special thread ?
If your answer to the above is YES, YES and YES then go ahead and take the risk

I mean the job

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mooseman