We were recently asked if we could sample rivets and the infrastructure 
engineer suggested that we could cut their heads off w/ an angle grinder 
(they seem to like angle grinders like some folks like duct tape) and 
then bash the rivet out. That immediately caused me to have suspicions 
as to the sanity of the engineer and put in question the entire RFP as 
possibly being a snipe hunt -- but a really neat structure to work on so 
now what? What I have determined is that to cut a rivet w/ a grinder 
risks overheating the rivet and thus test results may be skewed on any 
rivets so obtained... let alone bashing rivets to try to get them out of 
their holes makes no sense to me either in feasibility or as to what 
would be left over when we got done w/ that. His comment to that is we 
would be surprised. I am sure we would be surprised but I asked him if 
he wanted 5 rivets for samples then how many would we have to bash 
before we stopped being surprised? Samples for what?

So I got ahold of Patrick Sparks in Texas whom I know works on wrought 
iron and steel bridges (he had posted some really neat re-rivet vids on 
FB) and he recommended a mag drill w/ a special bit to core through the 
plate and not destroy/damage/alter the rivet. That came in about $3,000 
for 5 rivets, not accounting for our need to use a bungee cord and wet 
suit to access the desired extraction locations. But he also asked, 
"Samples for what?" He suggested a hand-held portable hardness tester 
(Mic 10)... those are not particularly cheap to obtain and not as 
accessible as a DVD frm NetFlix. The engineer suggested renting one... 
from where I'm still trying to figure that out, certainly not Home 
Depot. Having one in our hands and going around pinging rivets will not 
suddenly mean that we know what we are doing... so I also have to find 
someone that knows what they are doing?

Samples for what? Increasingly I find out that we need to ask that 
question up front. Turns out for tensile strength. We figure out and 
discuss in the field that even with a less invasive extraction 
methodology that what we will end up with in our hands might not clamp 
into a tensile testing machine.

Then this morning I wake up and I have a need-to-know question for BP. 
Do rivets work in compression or tension or both?

Thnx,
][<en

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