Bolts and Set Screws

[pmccarthy]

I wasted a couple of hours trying to buy 5/16 x 1 inch bolts. Couldn't get them anywhere. Everyone had that size in set screws. I wanted bolts, with some shank for good location and to avoid side wear in the hole. Eventually I went to Bolts and Fasteners company and was told that you can't get bolts in those small sizes anymore. People just buy set screws and don't know the difference. So that's what I had to do. The world is going to pot.

[spacesailor]

We in Sydney have a very Old company " Lee brothers " known as the ' nut house ' .

They always seem to have any bolt I need .

spacesailor

 

 

 

 

[onetrack]

No problem for me, about three quarters of my equipment is still imperial measure, and I can still buy small diameter nuts and bolts with unthreaded shank.

 

For the uninitiated, a set screw has the thread all the way to the underside of the head, a bolt has an unthreaded portion left on the shank. The unthreaded portion is called "the grip length".

 

https://www.bolts.co.uk/guides-and-tips/nuts-and-bolts/the-difference-between-bolts-and-set-screws/?srsltid=AfmBOorz9uoAZzWGYlnyzAjahbC9_I393ZObZqVf-KhImEWr_2_RS3H5

 

Bunnings Aerospace have them.

 

https://www.bunnings.com.au/pinnacle-5-16-x-1-yellow-zinc-hi-tensile-hex-bolt-nut-6-pack_p0054207?srsltid=AfmBOooMq-k1EoIb4wdKeohacwYrC4igOX30ri5pRdDa6AT60qHjJrJ_

 

 Most automotive parts suppliers have small Champion packs of nuts and bolts on a rotating stand.

 

https://championfasteners.com.au/product-category/blister-packs/bolts-nuts-packs-blister-packs/

 

Bolt and Nut Australia still call them nuts and bolts.

 

https://www.boltandnut.com.au/5-16-x-24-tpi-unf-fine-zinc-hex-bolts-high-tensile-grade-8?srsltid=AfmBOopblKy_pW6MFl1VWtNb8bYa5YUkQlvwOM2sRQQ0tkCPnt8QBObz

 

I buy a few bolts and nuts from AIMS Industrial or Blackwoods, but Caterpillar are the best for high grade fasteners, and for giving you the fastener specifications.

But you do have to have the Caterpillar "One Safe Source" book for the bolt and nut part numbers. It's readily available online in PDF format.

 

Edited August 26 by onetrack

[ClintonB]

Hi PMCcarthy,

did you check out AN bolt charts, AN5-7A gives close to 1/2 inch shank, 1.09” under head length and shouldn’t break due to decent strength.

Aircraft spruce should have them.

all of my work bolt racks have thread on full length at 1”, 1-1/4 on have shank and 1 inch of thread right up to 6 inch lengths I keep. 

[pmccarthy]

Thanks I gave up and used set screws which is apparently what others have done, the advice here will be useful next time.

[onetrack]

I only just noticed, that in the fastener links I posted above, nearly all the shorter lengths in small diameter bolts, are threaded all the way to the head, and are therefore set screws. Even a Caterpillar 5/16" x 1" bolt only has 1/4" grip length. It must be an SAE engineering standards thing (not that Cat follow SAE standards, they like to make their own).

 

I know your pain, and I've had the same problem many times before, where I needed a small bolt with maximum grip length, usually when a bolt shank has the likes of a clevis rotating on it.

What I do, is grab a longer bolt with the required grip length, and cut off the unnecessary threaded section. Trim the cut end on the grinder and wire wheel, so the nut goes on smoothly, and Bob's yer uncle.

[old man emu]

3 hours ago, onetrack said:

cut off the unnecessary threaded section.

Put the nut onto the bolt before you cut the bolt to length. Then unscrew the nut and you'll deburr the thread as te nut comes off.

[facthunter]

Better Also to Fix the thread where you cut it to Make it so it doesn't damage where it's going to Go and starts easily with a Chamfer and a bit of a lead in Especial with softer Metals Like Aluminium and High Tensile Bolts. Nev

[facthunter]

Loose Threads are WEAK threads. Nev