oversize bolt for 5/16-24 bolt repair

[GGU]

We have an aircraft pending repair with some holes damaged. Holes are used on a joint with AN5-6A bolts (5/16-24 steel bolts)
We can't go to AN6-6A cause we don't have enough edge distance in one of the joint members.
The damage can be removed by enlarging hole 1/64 and we have found two bolt references (NAS6705D5X and AIC791H05005X) that could be used but we haven't been able to find them on the market.

Can anyone recommend a more common bolt spec that has a 1/64 oversize to 5/16-24?.

 

[victorzv]

Will HL62-10 or similar fit?

 

[737eng]

Going with a Hi-Lok would provide for a nice assortment of oversize fastener options available and a very good solution, just check your hole tolerances to ensure you are maintaining the fit that you desire. Another option would be to change to another material bolt, perhaps a Ti NAS6805 or perhaps try a Boeing spec like BACBPE, BACB30NE, BACB30LN, BACB30PU, etc..... Ordering from Boeing you will most likely get the NAS hardware anyway, but anything is worth a try.

 

[rb1957]

how about modifying a larger bolt ? (thruning down the shank)

 

[GGU]

Thanks for the replies. HL64 is a good choice for us, now we only need to find a good tension nut.

 

[YoungTurk]

Have you looked at HL75 for the nut?

 

[GGU]

HL87 is the collar of choice for the tension bolt HL64. However, we are trying to use a nut instead of a collar as the joint is supposed to be removable.
We will use MS21133 nut, and are looking for a OS washer.
The only one I have found is MS14226, but spec appears to be cancelled. Does anyone know a newer spec for OS steel washers?

 

[rb1957]

do you Really need an OS washer ?? isn't there enough clearance with the existing or the next size up ??

 

[GGU]

Not enough clearance per spec dimensions. We will use standard washer and ream to an acceptable diameter.

Thanks everyone for your support.

 

[WKTaylor]

GGU..

Old... but usually available [LONG & SHORT Thread embedded in each spec]...
First OS [1/64"] NAS2903--2920 [NAS2905 = 5/16-1OS]
Second OS [1/32"] NAS3003--3020 [NAS3005 = 5/16-2OS]

Newest generation in one spec: Nom Dia, 1/64 OS [X] and 1/32-OS [Y], LONG thread [similar to AN spec]
NAS6203--6220 [NAS6205 = 5/16 Nom] steel
NAS6203--6220 [NAS6205 = 5/16 Nom] A286
NAS6203--6220 [NAS6205 = 5/16 Nom] Titanium [may only use with stress engr approval due to 1/2 stiffness of steel & CRES]

Newest generation in one spec: Nom Dia, 1/64 OS [X] and 1/32-OS [Y], SHORT thread [may require nut adjustment]
NAS6603--6620 [NAS6605 = 5/16 Nom] steel
NAS6703--6720 [NAS6705 = 5/16 Nom] A286
NAS6803--6820 [NAS6805 = 5/16 Nom] Titanium [may only use with stress engr approval due to 1/2 stiffness of steel & CRES]

CAUTION: review fastener specs for appropriate coding [coatings, undrilled or drilled head/shank, OS marking, etc]

Regards, Wil Taylor

 

[Lcubed]

GGU,
HiLoks, including tension HiLoks, often cannot be used to replace a bolt of the same size because of the head design. You may be able to use one, but be very sure of your loads and I suggest discussing with HiShear Co. If the loading is 'pure' shear you are probably OK, but since you are looking at a tension fastener system, I am assuming that there is some tension involved.
Best wishes,
Lcubed