Taps and dies

[AndyT]

Re starting a die, I second what AES says - you must have a taper on the rod that you are threading, whether you leave it there afterwards or not.
The way we were taught at school was to clamp the rod vertical in the vice, make sure we had the tapered (leading) side of the die downwards resting on the taper, and concentrate on keeping the handles of the die stock horizontal, not worrying too much about pushing down. Probably a good idea to start on something not too tiny - say, about 3/8".

One other tip nobody has mentioned when using hand taps or dies - rotate clockwise for about half a turn to make a chip, then go back a quarter turn until you feel a click as the chip is broken, then go clockwise again for half a turn. This avoids getting long bits of swarf trapped with nowhere to go, which could lead to a broken tap or ruined workpiece.

 

[Eric The Viking]

Thanks. I was sort-of taught by my dad, but metalwork wasn't an option at school, sadly (ere my life might have taken a very different path!). Always done the backing-off thing, too - I can't imagine not doing it now. And i've always threaded with some sort of taper, on the end of the workpiece, but not a long one.

 

[Phil Pascoe]

Don't forget that to clean up a thread in a hole or a nut, if you have a spare bolt that fits you can grind a section off it up to just before the diameter and run that through. It'll clean up enough damage to get you out of a jam.
Likewise, metalwork was first taught when I was in my fifth year so what I learnt I learnt off my my own back. I wanted to go to college to do engineering drawing but my father (a very successful builder) wouldn't allow it as the college was in his words "full of f****** hippy junkies".

 

[Phil Pascoe]

People have always thought I was a little nuts when I've built/installed a bench of any description and taken great pains to ensure it was level in both planes. You can see within reason whether something on the bench or in the vice is vertical or horizontal side to side, but not back to front.

 

[AndyT]

People have always thought I was a little nuts when I've built/installed a bench of any description and taken great pains to ensure it was level in both planes. You can see within reason whether something on the bench or in the vice is vertical or horizontal side to side, but not back to front.

+1 to that. My bench is horizontal, but the floor beneath it is not - it's probably about 1 1/2" lower at one end, and the floor goes in a gentle wave. That doesn't matter - but the level of the bench does.

 

[AES]

+ another 1 to that - it doesn't matter if the floor is level or not (within reason) but the bench & vice MUST be, both ways. Reason is just as Andy T says, when setting up to do anything in the vice (not just thread cutting but even "just" sawing & filing), half the battle is to get the job level in both planes before you start.

BTW, this thread hasn't 'arf drited - it started out with some poor bloke just innocently enquiring what taps to buy!

AES

P.S. While we're drifting, another useful tip to clean up a damaged female thread is to get a scrap bolt the same size/thread, then use a triangular file to carefully file three grooves into the bottom length of the bolt, spaced roughly equidistant around the periphery and set at about 15 degrees to the long axis. You ruin the bolt for normal purposes but it's a useful way of getting out of a problem if you haven't got a spare nut handy - you have of course just made a crude "tap".

AES ("bodgers united"!)

 

[Phil Pascoe]

I'm sure if he didn't know he's learned quite a lot by now.

 

[Eric The Viking]

While we're drifting, another useful tip to clean up a damaged female thread is to get a scrap bolt the same size/thread, then use a triangular file to carefully file three grooves into the bottom length of the bolt, spaced roughly equidistant around the periphery and set at about 15 degrees to the long axis. You ruin the bolt for normal purposes but it's a useful way of getting out of a problem if you haven't got a spare nut handy - you have of course just made a crude "tap".

AES ("bodgers united"!)

Haven't tried that, but I often hacksaw down across a diameter of a bolt, to make an impromptu thread cleaner. Works well for spark plugs, in particular (with a dab of grease so the crud doesn't fall into the cylinder).

Thread drifting? Serious doughnuts now!


Sorry I know I'm one of the worst offenders.

E.

 

[Bm101]

Brilliant, thank you all for your answers. I couldn't ask for better responses. As for the 'drift off topic', that's not drift that's just the sort of information that's really useful to someone like me. I'd read the tip about retapping the thread every half a turn but all the other information is new to me so feel free to carry on!
Reading summat in a book is one thing , the experience of people who have done it is sometimes far more valuable especially on a forum (the back and forth of it) so thanks for sharing and valued guidance. I've found many times that it wont help with that first step, you need to do it yourself, when it helps is when you make your first mistake or come to your first problem, then you remember all the little snippets and it's a lifesaver.

Cheers again guys
Chris

 

[MCB]

If you were looking a buying your first ones would you go for joblots offf ebay, a set or pay a little more for selected sizes and build up your collection as you went. With the last option, any particular make or seller I should be looking at? I've always been wary of buying sets of anything tbh.
Cheers
Chris.

I inherited a lot of Taps and Dies in various thread standards (BSW, BSF, BA , lots unidentifiable(!) and a few metric) but when I've needed new ones have bought from both Tap & Die company in north London and Tracy Tools in Devon.

Tap&Die will sell empty wooden boxes with pre-cut hollows for the taps and dies.

Tracy Tools have provided a first rate service - proper catalogue by post when requested.

MC

 

[bugbear]

Re starting a male thread (using a die), yes, it's a pipper that, I sympathise. I only use a lathe for that now (run by hand or VERY slow motor) but always had trouble before I got the lathe. About the only thing I can suggest without a lathe is to make a very exaggerated taper at the start of the rod to be threaded (file it in the pillar drill so it's pretty symmetrical) and then after the thread is cut, saw the offending taper off (assuming you have the necessary extra length to start off with).

There's a really handy gadget for braces - a die holder. The extra length of the brace allow much better control of the die's angle, and the brace's torque and speed are also handy.

This one's from an old eBay listing;

BugBear

 

[Bm101]

I inherited a lot of Taps and Dies in various thread standards (BSW, BSF, BA , lots unidentifiable(!) and a few metric) but when I've needed new ones have bought from both Tap & Die company in north London and Tracy Tools in Devon.

Tap&Die will sell empty wooden boxes with pre-cut hollows for the taps and dies.

Tracy Tools have provided a first rate service - proper catalogue by post when requested.

MC

Thanks MC. That's great. I'm really not sure how many sizes I'm going to need hence not yet buying a set although the old mouse finger has hovered dangerously a few times over the set Phil suggested. I need two specific sizes for my current little project. I'd rather build up a few as I go or indeed break them probably. I'll take a look. Thanks again all.

 

[AES]

That's a really natty little gizmo bugbear, thanks for posting. I'd never seen/heard of such a gadget before but it obviously makes a lot of sense if you don't have a lathe.

AES