Tap & die set advice, please.

[MusicMan]

Worth mention that solid hex dies are usually for thread chasing and split round dies meant for cutting new threads. There are of course rules to every exception.

Pete

True. You start the die thread with a split die, mounted so as to be as wide open as possible. Then close down and repeat. The equivalent of graduated taps.

If you buy the wrong sort, it's easy to slit a sold die with a Dremel and thin slitting wheel.

 

[J-G]

2. ... aluminium is harder (lubricate with WD40)...

Most of that is good advice but I must take exception to the WD40 suggestion ! (hammer) (hammer)

WD40 is a water repellent not a lubricant.

Lubricate Aluminium with paraffin.

 

[Inspector]

WD40 makes a better lubricant than it does a water repellent.

Pete

 

[Rorschach]

WD40 is an excellent lubricant for cutting and tapping and aluminium, it is better than paraffin and smells nice too.

 

[MusicMan]

I would not use WD40 for lubricating anything but aluminium, but it is good for that, in my experience.

 

[AES]

J-G wrote, QUOTE: WD40 is a water repellent not a lubricant. UNQUOTE:

and Music Man wrote, QUOTE: I would not use WD40 for lubricating anything but aluminium, but it is good for that, in my experience. UNQUOTE:

The first statement about WD 40 comes up so many times, but sorry, it's just plain wrong. Q: What is a "lubricant"? A: ANY liquid (or semi liquid/paste/slimy stuff) which will keep 2 pieces of metal apart while they're rotating or sliding or rubbing. In other words, water (OFTEN used as a lubricant, AND fuel of various types) and even raspberry jam COULD be used as a lubricant - though perhaps there are better uses for raspberry jam (my wife's is lovely)!

And although WD 40 IS primarily a water dispersant, it definitely IS also a lubricant - and maybe even better than raspberry jam for that purpose! Seriously, in certain special applications, WD 40 is a very GOOD lubricant and for some special purposes (in aviation for example) it's sometimes specified for exactly that purpose.

Coming back to the practical hobby workshop world. Music Man (amongst others) is perfectly correct when he states that although you'll find paraffin (kerosene) specified as lubricant for ali in all the text books, WD 40 works just as well as paraffin for cutting ali - that includes threading and lathe turning when you're after a fine finish. In addition, when turning brass, (which always "squeals" at you) though it's impossible to stop that squeal completely, a judicious squirt of WD 40 does a lot to at least reduce the teeth-jarring frequencies!

I also use WD 40 as a cleaner/lubricant for all my garden tools, with and without cutting edges. Some of these tools live in the relative warm/dry cellar workshop, the bigger ones such as the lawn mower and tree lopper live outside year round in a small timber tool store (unheated but with a small high level ventilator). In all cases cutting edges remain clean, sharp, and untarnished, and there is no rust at all on any tools, stored inside or out. And WD 40 is ALWAYS used (a quick squirt) as a lubricant on the pivot points on my wife's secateurs before and after use.

The "trick" of course is that after the "carrier fluid" has evaporated off, WD 40 leaves a thin film of silicon, which I think is why its use is frowned on in many wood working applications (where I understand silicon can adversely affect many traditional wood finishes).

But to say WD 40 is not a lubricant is just plain wrong, sorry - and to repeat, in some (limited) special applications it is actually specified as the only lubricant to use.

 

[Rorschach]

While I agree with a lot of what you say, I am a big fan of WD40 (and GT85). WD40 does not contain silicone.

 

[PaddyRedman]

As has been said, HSS for cutting threads, carbon steel for chasing threads. The amount of carbon steel taps I've snapped cutting threads is beyond the reasonable mark. Once snapped you've then got to try and get it out....
I always use a bit of drilling / cutting paste on steel, helps to ease the friction and makes the bit glide smoothly. Generally don't use aluminium so don't know what will work best on that.
GT85 smells nicer than WD40, and Ive found seems to last longer and work better.

 

[Rorschach]

GT85 smells nicer than WD40, and Ive found seems to last longer and work better.

I find it doesn't clean as well as WD40 but it does lubricate better and longer as you say.
I keep both on hand and use the GT85 mostly on our bicycles, it's a great water disperser for chains and sprockets and the lubricating properties easily last for the duration of a ride which is all I need.

 

[Robbo3]

I use GT85 as a lubricant on almost everything including the bed of the lathe.

 

[Harbo]

Cromwell sell some very good quality taps and dies including Dormers but at a price.
I started off with a cheap set from Axminster and added to it with better quality ones when they failed.

Rod

 

[Zedheadsteve]

With regards to using carbon steel taps and dies to repair damaged threads :

A much better option is to use “re-threading” taps and dies. These are specialist tools for cleaning up damaged threads and they remove minimal material to do this. The cutting tap or die option does tend to recut and therefore remove material which can be undesirable on worn threads.

The other advantage is that re-thread kits are fairly cheap. Save the money for good quality HSS cutting taps, buy the individual sizes you really need and forget the carbon steel options.

 

[Sheffield Tony]

I know this is an old thread, but I bought some individual taps from Chronos recently, they are marked Apex UK on the box, and HSS UK on the tap - and they work very well.

The set of Chinese no-name ones I bought previously (not from Chronos) were astoundingly useless. They simply would not start cutting a thread, internal or external - just chewed up the hole / end of the rod.

 

[Rorschach]

I know this is an old thread, but I bought some individual taps from Chronos recently, they are marked Apex UK on the box, and HSS UK on the tap - and they work very well.

The set of Chinese no-name ones I bought previously (not from Chronos) were astoundingly useless. They simply would not start cutting a thread, internal or external - just chewed up the hole / end of the rod.

Chinese made sets are quite often very poor however if you source them as single items or mini sets and make sure you buy HSS you will find that there are very well priced, high quality items available.

I have bought superb spiral point taps direct from China for about £1.50 per tap, they are strong and sharp and seem to be holding their edge fine.

 

[Ttrees]

Thanks for the tip about the cheap ones not starting, I will look out for that happening.
I've only bought a cheap Lidl the other week and must have another look at them.
What i have noticed is on these cheapies at least the dies are at least centered, compared to a pack I bought about 10 years ago.
I bought them mostly for the wrench can't go too wrong as they were half the price of a single pack of good ones...beats using a vice grip
Do you folks use the cheap wrenches that you get with these packs,?
Is it scornful to use a cheap wrench that comes with these taps for fancier taps?
Should I be looking for one of those fancier chuck style wrenches on the bay for cheap?
The ones locally are about 25 quid.
Thanks
Tom

 

[AES]

I really have found that cheapo "Chinese Cheese" taps & dies are very much a matter of pot luck. Example, I have a set of either Lidl or Aldi HSS Metric Coarse - 2, & 3 mm, then 2mm steps up to 12 mm, and they're VERY good. OTOH I've got another cheapo set (I forget where from) and "they wouldn't cut a thread in a rice pudden skin".

Trouble with all this is you don't know until you try, but at least the Aldi/Lidl 3 year guarantee seems to work fine the few times I've tried - the lady in the shop here just takes the item back, no Q's asked, and if in stock on the shelf, you get the choice of a "new" item or your money back..

Re tap wrenches, the tap wrench in my OK "Laldil" set is also "OK", but for the smaller sizes (small mm, BA, etc, etc) the M&W "2 jaw collet-type wrench" that I inherited from my Dad is great - small and delicate enough that the chances of breaking a tap or cutting a cock-eyed thread is greatly reduced.

Nowadays though, I generally buy single taps and dies as needed, rather than full sets, and can therefore afford to buy better brands (via Chronos, Arc Euro, Model Fixings, etc. Usual disclaimers, links at top of Metal Working section).

 

[Ttrees]

Thanks for the info AES
I presume the Moore and Wright collet type wrench that you have is something like this one
pulled from a quick Google

I will do some more looking up when I have time.
Good to know both wrenches I got in the pack are OK from your perspective, I only got them for some unforeseeable job.
I'm normally only looking to do non precision stuff, but have a bought the few good ones when I needed them.
I might be making four M10 barrel nuts in the future and might opt for something like a chuck type wrench for the job, or maybe fix my pillar drill return spring and try that out.
Threaded a hole with a monsterous old metalworking lathe before and couldn't believe the smoothness 8) , so that's probably a better idea for now.

Thanks
Tom

 

[AES]

Yup "my" (my dad's old) tap wrench is exactly like that one. Sorry, I don't even know if they're made any more.

 

[TFrench]

Yup "my" (my dad's old) tap wrench is exactly like that one. Sorry, I don't even know if they're made any more.

Eclipse still make them (no. 143) but there are that many on ebay you'll soon pick up a decent one for pennies.

 

[Trevanion]

I had a cheap set for a while from Aldi, I think it was something like £10-15, worked OK but they didn't last long making new threads so I guess they were mainly for cleaning up and re-cutting old threads.

I've steadily bought sets of Presto HSS taps and dies when I needed them and now I have a range from M3 to M12 and a couple of BSW sizes, they're not cheap but they do work that much better at cutting new holes. They bite into the material pretty instantly compared to the cheap Chinese ones and it's a much cleaner thread without any chipping of the thread itself. As for tap wrenches, I found the cheapie 10" Aldi one to be pretty rubbish and it constantly lost grip mainly down to the sloppy fit of everything I think. At the moment I've officially only have two sizes of tap wrench, 6" and 22"! :lol: I bought a vintage 6" Eclipse no 241 a couple of years ago and it's excellent on all the Presto taps up to even M10, even though it's only 6" in size but I think sharp taps help greatly. I recently bought a 22" Record tap wrench for pennies that is military broadmark stamped 1942, I'll never be driving taps that'll do it justice and it'll mostly sit in the drawer for its whole life but hopefully it will come in handy!

Anyone know where to get a decent set of tap size drill bits? I could buy singles but it would be nice to have a set with some kind of holder.

I think good die stocks are a must though, they should hold a die squarely in the holder and firmly, any play or out-of-squareness makes it so much harder to cut a thread. Fortunately, most of my external thread cutting is done on the lathe with a holder in the tailstock 8)