What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Is BSPQ-5-4 rivet a Q rivet or N rivet?

S

seattleworm

Well Known Member
Sponsor
Here is what happened to me. I messed up the rivet hole for a 470AD4 rivet that attaches HS405, HS702 and HS714 by drilling it out twice, all because I want to have a better looking rivet. The hole is enlarged and I have to drill it to next size rivet hole using #21 drill. I wanted to put a 470AD5 rivet there, but none is available at the moment. I found the 6 BSPQ-5-4 pop rivets that came with the empennage kit. Really 4 is needed, so I have 2 spare. I checked the shear strength of BSPQ-5 rivet to be 525 lbs (http://www.avdel-global.com/fileadm...ial/Breakstem/Q_Rivet_BSPQ_BSLQ_BSCQ_inch.pdf), while the shear strength of 470AD4 is about 360 lbs. So I went ahead using the BSPQ-5 rivet to replace the 470AD4. No long after, I found on the bag that packs the BSPQ-5 rivet reads "N Rivet BSPQ-5-4", hmmm...... I then checked the shear strength of BS serious of N rivet, it's about 260 lbs, lower than the 360 lbs that 470AD4 will give. Shouldn't be BSPQ-5 a Q rivet because the fourth letter is Q? Also, one of the difference between N and Q rivets is that N rivet will have a hollow rivet (the steel shank will be pulled out after popping). My I checked BSPQ-5 after popping and it has the steel shank there. Anyone can help to clarify?

90r0nb.jpg
 
Right!

Cherry "Q" rivets have the "Q" as the fourth letter.
Cherry "N" rivets only have 3 letters.
 
If the end of the mandrel that deforms the aluminum body of the rivet has these little serrations on it, it's almost certainly a Q rivet:

q-rivet_serrations.png


Thanks, Bob K.
 
Thanks, Mel!

So, it should be a Q rivet that with a higher shear strength. I don't know why Vans calls it "N rivet BSPQ-5-4". But I think as long as the steel stem is in there, I am good. Just need to check it regularly when it is flying time (hopefully within 4 years, I just started building 3 wks ago). this place looks to me should be easy to do a visual check.

Lesson Learned Number 1: DON'T DRILL OUT A RIVET JUST BECAUSE IT DOESN'T LOOK GOOD! It will end up an even worse one, especially in this kind hard-to-reach area.

__________________
Shawn
RV-7 Empennage
HS - 90% done
 
Thanks, Bob! The steel stem has serration on the end. This just confirm it should be a Q rivet. I can sleep better now

_____________
Shawn
RV-7 Empennage
HS - 90% Done
 
Just to get this clarified by Vans answer. "The BSPQ is a Q rivet, the N is part of our number system which is not relevant, so it will be OK (to replace 470AD4 rivet using BSPQ-5-4)"

Shawn
 
Good and Better

You have just discovered the Talpos Principle:

The worst enemy of Good is Better.

Best regards,

Jonathan Bodine
 
Hey Shawn,

i had exactly the same issue. i put in some BSPQ-rivets but replaced them later with cherry max rivets. the best solution would have been to leave the ugly 470 rivets as they were.

Kay
 
You must log in or register to reply here.
Back
Top