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Boeing Fasteners 2
- Thread starter Bazzo
- Start date
I don't have a number to number conversion... but I can tell you the following info:
BACB30MY and BACB30VT are protruding shear head hi-loks
BACB30NX is a protruding tension head hi-lok
BACB30NW and BACB30VU are countersunk shear head hi-loks
BACB30NY is a countersunk tension head hi-lok
I can provide more detailed info when I visit my other office next week. The above are for nominal size fasteners. There is additional conversion for oversizes.
BACB30MY and BACB30VT are protruding shear head hi-loks
BACB30NX is a protruding tension head hi-lok
BACB30NW and BACB30VU are countersunk shear head hi-loks
BACB30NY is a countersunk tension head hi-lok
I can provide more detailed info when I visit my other office next week. The above are for nominal size fasteners. There is additional conversion for oversizes.
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Thanks debarra
I have a BACB30NW fastener, I only have the spec for a cres BACB30 (the letter code is in the office) The NW Is probably Ti. It’s a problem I have often as the Airbus SRM calls out HL fasteners, there’s a conversion in Chapter 51 but only includes DAN, FoN and such. It’s a shame Big B do not give a call out in HL, or is there a difference that I don’t know?
I have a BACB30NW fastener, I only have the spec for a cres BACB30 (the letter code is in the office) The NW Is probably Ti. It’s a problem I have often as the Airbus SRM calls out HL fasteners, there’s a conversion in Chapter 51 but only includes DAN, FoN and such. It’s a shame Big B do not give a call out in HL, or is there a difference that I don’t know?
Hi Bazzo.
BACB30NW is an countersunsk head shear hi-lock nominal made of TI 6AL4V 95KSI shear strength
you could use HL11 countersunk shear head hi-lock with the same material and shear strength nominal too.
boeing use X for 1º oversize, and Y for 2ª
R1 of HL11 is HL111, and R2 is HL411
yuo only need add. the finish coating the most usual are
VAP or VAZ aluminium coating
I hope this information could help you.
you can too send me and e-mail
debatarra@telefonica.net![[2thumbsup]](/data/assets/smilies/2thumbsup.gif "[2thumbsup] [2thumbsup]")
BACB30NW is an countersunsk head shear hi-lock nominal made of TI 6AL4V 95KSI shear strength
you could use HL11 countersunk shear head hi-lock with the same material and shear strength nominal too.
boeing use X for 1º oversize, and Y for 2ª
R1 of HL11 is HL111, and R2 is HL411
yuo only need add. the finish coating the most usual are
VAP or VAZ aluminium coating
I hope this information could help you.
you can too send me and e-mail
debatarra@telefonica.net
The Boeing D-590 Parts Standards manual lists, in the individual listing for each standard, the manufacturer's part number for each of their products that are qualified to that standard (the hiloks, that is; this type of coverage is somehwat spotty for other types of standards, esp. the older ones).
What's even more aggravating is Boeing's use of fastener codes. Their repairs contain their own (usually) three-character fastener codes, which you then have to look up to cross to the BACB30 part numbers, which you then have to look up in another table to cross to the HL part numbers.
At least oversize fasteners are easy with Boeing part numbers: add an 'X' to the end of the complete part number for 1/64" over nominal; add a 'Y' to the end for 1/32" over; and add a 'Z' to the end for 3/64" over (though the 'Z's are pretty rare, and expensive when you can find them).
Regards,
Sean Shenold
What's even more aggravating is Boeing's use of fastener codes. Their repairs contain their own (usually) three-character fastener codes, which you then have to look up to cross to the BACB30 part numbers, which you then have to look up in another table to cross to the HL part numbers.
At least oversize fasteners are easy with Boeing part numbers: add an 'X' to the end of the complete part number for 1/64" over nominal; add a 'Y' to the end for 1/32" over; and add a 'Z' to the end for 3/64" over (though the 'Z's are pretty rare, and expensive when you can find them).
Regards,
Sean Shenold
- Thread starter
- #8
Thanks Sean, that is my problem, I receive the repair drawing telling me they have used BAC whatever on an Airbus and we have no real cross reference, apart from what you can put together unofficially, and working for Airbus, I don’t have access to Boeing standards manuals.
HSThompson
Aerospace
laXXX,
Try the HL48 - Protruding Head, A-286, 95ksi shear, cad-plate.
BTW that is just the basic pin. If you know the fastener code I could be more specific. (ie. BACC30? collar).
HST
Try the HL48 - Protruding Head, A-286, 95ksi shear, cad-plate.
BTW that is just the basic pin. If you know the fastener code I could be more specific. (ie. BACC30? collar).
HST
HI laXXX
There are 3 different hex drive bolts with the same basic
part number all of them protuding head shear type 95 ksi
BACB30FM steel cadmiun
BACB30FM( )A A286 cadmiun
BACB30FM( )A-U A286 passivated
Mating collar BACC30M or BACC30AG
Could you confirm that there aren,t any letter after FM
regards deba
There are 3 different hex drive bolts with the same basic
part number all of them protuding head shear type 95 ksi
BACB30FM steel cadmiun
BACB30FM( )A A286 cadmiun
BACB30FM( )A-U A286 passivated
Mating collar BACC30M or BACC30AG
Could you confirm that there aren,t any letter after FM
regards deba
You might want to go to They have alot of cross reference information on Hi Loks. If you don't want to join, call them and ask for Jennifer. She will probably give the info. for free.
Bazzo...
SOME of the older BACB30** and BACC30** "hex drive bolt and collar" specs have HL-base part numbers embedded on the last pages of the specs.
MOST newer BACB30** and BACC30** "hex drive bolt and collar" specs have NO HL-base part number references... and a detailed 1-to-1 review/comparison of specs [BACB30** to HL**] will allow You to determine "approximate equivalents".
Regards, Wil Taylor
SOME of the older BACB30** and BACC30** "hex drive bolt and collar" specs have HL-base part numbers embedded on the last pages of the specs.
MOST newer BACB30** and BACC30** "hex drive bolt and collar" specs have NO HL-base part number references... and a detailed 1-to-1 review/comparison of specs [BACB30** to HL**] will allow You to determine "approximate equivalents".
Regards, Wil Taylor
When using oversize hi-loks, note that the BACB30MY6()X and Y Hi-Loks are obsolete due to problems with the fastener heads during production. Since the MY is a shear head protruding head hi-lok, when oversizing these fasteners use the NX tension head oversize fasteners. NOTE: this is only applicable to the 3/16" dia, all other diameter MY oversizes are OK. Reference BAC Service letter 737-51-037-A. I would assume this would go for the equivalent Hi-shear HL10, oversize, as well, but am not sure.
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I have an old cross over for most fasteners but.....
Call your local hi shear rep and he can send you a CD with a complete cross over. You can sort it by BACB or by HL. Since the are a primary supplier I have yet to find one, BACB number, not listed. Though I guess there might be. I didn't think it was that tough?
Doooooh!
Al
Call your local hi shear rep and he can send you a CD with a complete cross over. You can sort it by BACB or by HL. Since the are a primary supplier I have yet to find one, BACB number, not listed. Though I guess there might be. I didn't think it was that tough?
Doooooh!Al
- Thread starter
- #16
Thanks for all your posts, they’ve been a great help. The problem I have is we get repairs for Airbus aircraft which we should approve, but the airline has used Boeing Bacs. The allowables that we have are for HLs or Dan. Usually what happens is we get back to the airline and ask for the spec and search through to see if we can find the equivalent HL. With a conversion list this is a bit more easier.
What I’m doing now, with your suggestions is making a list of my own.
What I’m doing now, with your suggestions is making a list of my own.
First, the disclaimers:
1) I speak neither for Boeing nor Airbus.
2) My exposure to Airbus fastener callouts is dated.
3) Take information from any source (including that I’m about to give you and point you to) other than directly the from OEM Part Standards (and Product Specifications) involved with a grain (better yet, a pound) of salt.
4) I am of the opinion that some treat aerospace fastener substitutions cavalierly. A disturbing, and potentially dangerous, “any part that fits” mind set is not uncommon. This observation is not directed at anyone in this thread.
“Hi-Loks” vs. “Lightweight” Pin Systems
BACB30VT and BACB30VU are not “Hi-Lok” Pins. Go to and type in “BACB30VU” and then “BACB30VT”. Note that the descriptions given for these part numbers starts with “LTWT” (for “Lightweight”). Neither BACB30VT or BACB30VU are “Hi-Lok” Parts, but rather “lightweight” pins (“Hi-Lite”, “Aero-Lite”, “Veri-Lite”, etc.). My 7 Jun 05 2:04 post in thread31-121526 details some of the reasons why “Hi-Lok” and “Lightweight” components should not be mixed, and why a certain amount of precision (pickiness, if you like) is warranted in labeling/describing them.
Finish Codes:
Take a look at I filtered this spreadsheet on the first column for either “Boeing” or “Airbus” and then sorted (descending) on the third column (Hi-Lok Part Number) and scanned the result. It appears to confirm my memory: Even in the instances where Boeing and Airbus have developed company standards based on the same “basic” Hi-Lok Part Number, they typically specify a different coating/finish for their parts. Before accepting any such substitution, one of the things that I would (personally) be very sure of was that I fully understood any potential ramifications of these differences in specific application/location where they were installed.
Airbus And Metric Hi-Loks:
1) I speak neither for Boeing nor Airbus.
2) My exposure to Airbus fastener callouts is dated.
3) Take information from any source (including that I’m about to give you and point you to) other than directly the from OEM Part Standards (and Product Specifications) involved with a grain (better yet, a pound) of salt.
4) I am of the opinion that some treat aerospace fastener substitutions cavalierly. A disturbing, and potentially dangerous, “any part that fits” mind set is not uncommon. This observation is not directed at anyone in this thread.
“Hi-Loks” vs. “Lightweight” Pin Systems
BACB30VT and BACB30VU are not “Hi-Lok” Pins. Go to and type in “BACB30VU” and then “BACB30VT”. Note that the descriptions given for these part numbers starts with “LTWT” (for “Lightweight”). Neither BACB30VT or BACB30VU are “Hi-Lok” Parts, but rather “lightweight” pins (“Hi-Lite”, “Aero-Lite”, “Veri-Lite”, etc.). My 7 Jun 05 2:04 post in thread31-121526 details some of the reasons why “Hi-Lok” and “Lightweight” components should not be mixed, and why a certain amount of precision (pickiness, if you like) is warranted in labeling/describing them.
Finish Codes:
Take a look at I filtered this spreadsheet on the first column for either “Boeing” or “Airbus” and then sorted (descending) on the third column (Hi-Lok Part Number) and scanned the result. It appears to confirm my memory: Even in the instances where Boeing and Airbus have developed company standards based on the same “basic” Hi-Lok Part Number, they typically specify a different coating/finish for their parts. Before accepting any such substitution, one of the things that I would (personally) be very sure of was that I fully understood any potential ramifications of these differences in specific application/location where they were installed.
Airbus And Metric Hi-Loks:
My (dated) memory is (oddly enough) that the vast majority of Hi-Loks specified by Airbus were “inch” and not “metric” parts. The cross-reference file link provided (assuming it is relatively complete and current, a couple of pretty whopping assumptions) appears to confirm this. Filtering for part numbers with “HLM” (Metric Hi-Lok) and “HSTM” (Metric Hi-Lite) prefixes reveals not a single “Airbus” or “Aerospatiale” part number.
'Tis true, Airbus uses inch bolt sizes. They're usually quoted as the size in mm (1/4" will be called out as a 6.35 mm), but inches they are. Not sure how exclusive this is; anyone know of any true metric bolts used on Airbus?
I've always assumed this was a cost/availability/repair decision made early on. It does seem a little odd. I'd have expected the French to have pushed for metric even if it was going to be initially costly.
I've always assumed this was a cost/availability/repair decision made early on. It does seem a little odd. I'd have expected the French to have pushed for metric even if it was going to be initially costly.
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