Titanium true cycle thread (BSC) bolts

I made these a week or two ago and have been waiting for a 7075 alloy bolt to come back from the anodisers. They are 3/8 and 5/16 true cycle thread bolts, ie 60* angle. you can easily get 26 tpi taps and dies as BSB thread form but they are 55* angle. Which to be honest on small stuff like this doesn’t make a lot of difference, but i like to do it right. I’ve done loads of these types of bolts for a customer, the heads are Whitworth sizes for Whitworth spanners and are slightly domed, i even have a tool ground up to profile the heads just for his bolts!

Titanium BSC bolts

oddly the photo has distorted the 3/8 bolts making them look bent! that would be a feat of engineering – machining bent bolts! Unfortunately i can only make straight bolts!

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