Making My Own Bolts

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In being interested to advance my knowledge and skills since retiring I have been viewing videos on YouTube as regards tapping dying threads.
But one thing I have been so far unable to find is after threading a rod how would I create a head on it to use a spanner etc.
 
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An alternative is to start with a rod of diameter greater than your thread and lathe turn only part of the rod length down to the thread diameter. Then machine/grind/saw flats on the larger diameter part to make the head.
 
Without knowing why you need to make bolts - Consider the tensile strength (sheer strength) of the raw material and is it up to the standard required if it is for something important.
 
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An alternative is to start with a rod of diameter greater than your thread and lathe turn only part of the rod length down to the thread diameter. Then machine/grind/saw flats on the larger diameter part to make the head.

or start with Hex stock, turning the majority into round, then either using a die or machining a thread onto the end.
 
I am pretty sure that the earliest "bolts" were actually threaded rods with a square plate on each end. Eventually someone decided that one end could be made with a head. Don't know if the first was simply a square heat welded on in a forge?

I did some work once with an archeological blacksmith who made Roman weapons etc. very interesting.
 
I am pretty sure that the earliest "bolts" were actually threaded rods with a square plate on each end. Eventually someone decided that one end could be made with a head. Don't know if the first was simply a square heat welded on in a forge?
The first technique you refer to is often used to stabilise masonry walls which are bowing. We still do something similar today, although resin fiastenings have more or less taken over in recent years

I've seen a fair few old fixings in listed buildings but having done a small amount of forge work a few years back I seriously doubt that a welded head would be strong enough. I think it would also be much more work to forge weld the head of a bolt onto the shank. I suspect that before the invention of appropriate machinery the round, unthreaded bars would simply be heated at one end introduced into a square die with a hole in the middle of the recess and formed by hammer forging (into the shaped recess) in a similar manner to the way that rivet heads are formed by a hammer and die (both cold and hot). Forming a square at the end of a round bar by hammer work alone is possible, but the clean undersides to the many old bolt heads leads me to think they were forged using some form of die or at the very least a swage block.

Early threads weren't turned or rolled (machine lathes to do this sort of work would have to wait for Whitworth) but some show signs of hand cutting, although I wouldn't be surprised to find that they had been formed, at least in part by again heating the metal and using a die box to form the thread. I have seen quite a few smaller wood/coach screws which are definitely cast as a single piece
 
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you could hot-forge steel bar to form a head on the end.

But why would you?
 
you could hot-forge steel bar to form a head on the end.

But why would you?
For A-level metalwork? Been there, done that. :confused: A more difficult thing is to thread it without access to a lathe or threading dies
 
Being the OP I thank you all for your answers to my question.
I realise now that if I wish to bolt two pieces together I drill a hole in one part and create a thread in it using a tap and then purchase a ready made bolt.
 
Check out tapping size drills too.....although for general DIY projects more standard sizes will do- clearance sizes similarly apply.
Only buy quality HSS taps and split circular dies - carbon steel ones are useless.
John :)
 
I got given a set of Goliath taps and dies a few years back, great bit of kit but dread to think what they cost new!.
 

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