- This topic has 21 replies, 5 voices, and was last updated 19 years, 1 month ago by
Chris LaPanse.
Chris LaPanse.-
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denverdoc
a nutsert device can be had for about 20 bucks at Harbor–there is one in Greely, several in denver/metro and I’ll bet in FC. Great tool, maybe the Chinese clone I bought isn’t as good as the original sold by Spruce Aircraft Supply out of LA, but plenty functional for rockets, and scads cheaper. I have used pem nuts, plastic rivets, etc, and nothing comes close to the ease and strength of these ties. The one area where it may be an issue is into FWFG–the surrounding material has to expand a bit for the nutsert to bite. I heard a cracking sound when I put one into FWFG coupler–no visible damage, but nonetheless, when possible, now will line the interior with kevlar, and drill a 64th inch larger pilot.
John SBruce R. Schaefer
The one area where it may be an issue is into FWFG–the surrounding material has to expand a bit for the nutsert to bite. I heard a cracking sound when I put one into FWFG coupler–no visible damage, but nonetheless, when possible, now will line the interior with kevlar, and drill a 64th inch larger pilot.
John SJohn, the snap or crack you’re hearing is the nut-sert/threaded-insert breaking in half–if you’re using the flush-mount ones, the other ones just smash into place. It separates, and the bottom jams up into the half above causing the expansion and proper seating. I used it in G10 spiral wound fiberglass, and you always hear the crack or snap regardless of the material. I used it on the hatch and screwing some sections together. Going to use it on the rail buttons tomorrow evening, if I’m sure the line up is straight. Just make sure the larger pilot hole isn’t too large, or it won’t seat tightly enough. I have the Chinese version, too, and it’s fine.
Conway Stevens
Ive used these on wood, G10, FWFG, Convolute wound glass, metals, and much more and yes they (if using the flush ones I normally get) will make a crack/snap noise as the lower portion of the nut rivet snaps away and up into the upper portion causing it to expand and bite. I wouldnt worry to much. Belive it or not if the hole is to small it wont even allow for the rivet to insert let alone try to pull back up through itself.
denverdoc
Con,
Maybe. These riivnute aren’t quite flush, but file down nicely owing to the cheap metal they contain. Put them into several materials w/o that cracking sound, but I didn’t see any spider webbing either in the FG. Good tool in any event, but I do know kev takes it better than CF–latter caused an obvious delam from the FWFG tubing in which it was ballooned–I know not a good technique for internal composite reinforcement, but the inside out method with vac is time consuming and eats material like no ones biz.
John SConway Stevens
No worries Bruce we got-er covered. Actually you will need to drill the holes the next size up wich is 1/4 inch. The nutsert inserts o.d. slip into that hole and then with the tool rivet them in place and they flush mount nice and very tight. So that way the retainer isnt setting higher either. The center hole is 8-32 thread just what the doc ordered.. problem solved. I belive that drilling the holes larger to 1/4 is better then turning and drilling even more holes. I wouldnt feel comfortable with that let alone the nutsert insert is way stronger and can be unscrewed and screwed into time and time again. I would bet the glass over time would wear out pretty fast.. and just having all those holes… not my liking.
Bruce R. Schaefer
John, the ones we use are the aluminum ones; you can also get them in steel (http://www.rivetsinstock.com/rivet59.htm). And, yep, I’ve had to file some down to round ’em out, too. No biggie. But the ones on my hatch, for some reason, didn’t need any filing down. Go figure.
denverdoc
These are the aluminum ones. Very soft, easily filed, and when put into anything but FWFG make not a peep. The cracking sound I referred to is real–i’ve only been using them for 6 months or so, so dont have that much experience with the tool. So would still recommend overdrilling the nutsert bore by 1/64 in FWFG. With a hand drill, no need cuz of its built in slop, but using a vise and drill press, something to consider.
John SBruce R. Schaefer
No argument. 🙂 With the ones I used on my aft end to hold the Aero Pack 98mm retainer, I did brush epoxy around them very lightly. Hey, I’m paranoid, gimme a break! 😀
Conway Stevens
Now I know mine isnt FWFG as its Convolute wound glass tube but I used these for my screw points for the upper airframe and lower airframe to screw to the altimeter bay. Didnt have to file them one bit. They slid in pretty nicley and for the #8-32 inserts I used a 1/4 inch bit. If you want to see pics I have them posted at my L3 thread at TRF.
Bruce R. Schaefer
Mine is G10 spiral wound fiberglass. I bought mine from the same source as Conway, so I honestly don’t know about the other FB type, filament wound? Wait, I know… I have rocket that’s filament wound, sometimes you drill into it and end up with a fiberglass filament hanging out?
At least I did on one hole… 🙄
denverdoc
Bruce R. Schaefer
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