Can't find 5/16" bed headboard bolts!!!

Mandrake · Post by **Mandrake** » 28 Feb 2015, 20:06

Hi All,

Not car related in the slightest, but we are moving house so our bed which has been in storage for 18 months while we stayed elsewhere needs to be reassembled only to find that some of the bolts are missing!

It's a solid wood frame using 3" threaded studs with half moon spacers, washers and split washers, This is what they look like:

The head board and foot board have inserts threaded into the wood to take the studs and the side beams have circular cut outs for the nut and half moon spacer. The problem is they appear to be imperial (most likely 5/16") and 99% of suppliers in the UK can only supply M6 or M8!

We've driven to I don't know how many furniture and hardware stores and nobody has them. I ordered a replacement set online before realising the originals weren't M8, so they are no use. (Although the half moon spacers, wood dowels and washers fit...)

I've been scouring the internet today trying to find them but nobody seems to sell them. Although I'm reasonably sure that they are 5/16", and they need to be about 3" long, I don't know what thread pitch they are, whether they are BSF, UNF, UNC etc... I don't know much about imperial threads types unfortunately...

Can anyone help me find some or at least confirm 100% what thread I need ? At the moment we have a £500 bed that is only 5 years old that is just a pile of rubble on the floor, and SWMBO is not happy...

I now only need 8 studs and nuts - I've managed to piece together everything else I need.

addo · Post by **addo** » 28 Feb 2015, 22:19

Use your sliding calipers and the Maryland Metrics thread identification charts, to determine the thread.

NewcastleFalcon · Post by **NewcastleFalcon** » 28 Feb 2015, 23:22

My local Agricultural Engineering outfit I find have all sorts of metric and imperial bolts, fastners and threaded rods. Probably get sick of me rooting around, coming out with a handful of nuts bolts and washers and paying 79p for them! In comparison it makes the occasions much worse when I have to enter Halfords and pay through the nose for a few nuts and bolts in plastic packs.

Regards Neil

addo · Post by **addo** » 01 Mar 2015, 06:36

Worst case you could buy some threaded rod and cut your own.

BTW graphite powder reduces the creaking.

Chris570 · Post by **Chris570** » 01 Mar 2015, 08:58

addo wrote:Worst case you could buy some threaded rod and cut your own.

BTW graphite powder reduces the creaking.

I'm so pleased there was a smutty reference in this thread, I was getting worried for a moment I wasn't on the FCF, thanks for bringing me back to reality

Mandrake · Post by **Mandrake** » 01 Mar 2015, 10:44

Ok I've measured the thread pitch and it's 18 tpi. So looking at various spec charts it appears it will be either 5/16" UNC or 5/16" BSW - as they both have the same thread pitch but a slightly different thread angle and contour.

So which one of those two is it more likely to be on a UK bed ? Are they close enough that they can be interchanged, perhaps in one direction only ? Some of what I've read suggests you can get away with mixing the two standards but it isn't clear whether you can mix a BSW nut with a UNC bolt, or vica versa, or both ways ?

Mandrake · Post by **Mandrake** » 01 Mar 2015, 11:20

I've just ordered both BSW and UNC versions of the studs and nuts from these guys:

http://www.gwr-fasteners.co.uk/" onclick="window.open(this.href);return false;

One of them should fit!

When I have them, what's the best way to determine which matches correctly - will I be able to tell by comparing them by eye to the originals, or will they feel loose if I mix the two types ?

citronut · Post by **citronut** » 01 Mar 2015, 14:22

Simon you will just have to bang your head against the wall

till you sort your bolt whoooops i mean bolts out

daviemck2006 · Post by **daviemck2006** » 01 Mar 2015, 21:13

It will be worse sorting his nuts [emoji12] [emoji13] [emoji15] [emoji35] [emoji33] [emoji6] [emoji1]

Sent from my GT-I9300 using Tapatalk

addo · Post by **addo** » 02 Mar 2015, 11:04

Can you not compare the "feel" of the old and new pieces of fastener screwed together? If it's UK made, most likely to be BSW IMHO FWIW; IOW YMMV.

UNC is much more a US market thread.

Chris: I'm delighted to fulfil a necessary role in FCF. With neither smut nor innuendo, we may as well be an embroidery group.

BX · Post by BX » 02 Mar 2015, 18:28

Where BSW and UNC have the same pitch they are interchangable in practice. The threads are never cut accurately enough for the difference in thread angle to make a dufference. Many agri parts stores have the unc version. They are common on many older tractors and machines. Major manufacturers such as Ford MF and IH even though they had European plants were run from the other side of the Atlantic.

Mandrake · Post by **Mandrake** » 07 Mar 2015, 00:34

Thanks everyone, the bed has been reassembled.

By comparing the thread visually with the old one it looks like the original is BSW - which has the pointy thread profile while the UNC one has a flattened thread profile.

Annoyingly, while the studs were correct (I bought some BSW, some UNC to cover all bases) the nuts that were labeled as BSW in fact weren't - they had the wrong thread pitch to fit, and they didn't fit M8 bolts either! So no idea what they are...

So I ended up having to use the BSW studs with the UNC nuts. And then the day after assembling it the original set of bolts were discovered after 2 weeks looking for them... (I'll save my expletives...)

addo · Post by **addo** » 07 Mar 2015, 02:20

Did you not think they would turn up at such a precise time?

I'm fortunate to have a good fastener shop barely ten miles away. Even picked up some ¼"-20 halfnuts from them yesterday (admittedly, they were surprised to have some in a dusty box).

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