Taps Dies and thread taps - where to start?

[Peaklander]

Hi

I could count on one hand, well maybe two, how many holes I've cut a thread in over the years. So that tells you I have no experience. I have had to clean holes and screws in the past and I've done it a variety of ways, rarely with a proper set of taps / dies.

In preparation for doing my first timing belt change on my 300TDi I read that it's probable that I'll need to pull the crank pulley as it won't be free and therefore it's advised that the four threads are cleaned first. I don't know how likely this is but I thought that I maybe could buy a single tap and holder just in case and I'm sure a 10mm tap would be useful.

 

However I started to look at stuff for sale and I was inevitably drawn to full sets and that's when I remembered that there are three types of tap and in fact the last time i needed a tap for a proper task, it had to be a bottom tap as it was a blind hole. Most of the cheaper sets only have two taps and in fact I don't have enough faith in them having metric fine and coarse threads as well as the differing types. I presume that even at the ripe old age of 50-something (well a lot more than 50), a nice big set in a wooden box, like the toolroom professionals  have, would be a waste.

Then I saw that actually for learing threads rather than cutting, I'd be better off with a thread chaser - is that the correct term? If so, maybe they are what i need for most Land Rover repair and restoration work (thinking rusty, painted or galved holes etc.). So I was wondering about this kind of item.

Could anyone help me decide what's best? Would a selection of these be better for clearing or would a basic set like this be a better buy, considering that it's likely that as time goes on, I'll spend more time "in the garage"?

Thank you

[vulcan bomber]

Taps like everything else are nasty when they are cheap.

 

Dormer, SKF, Geuring all make good taps. For hand tapping you get a first, second and bottoming tap, there pretty self explanatory. Machine taps come as spiral point and Spiral flute, they also can be used by hand, I generally try to avoid using spiral flute taps by hand, they in my opinion, are the easiest to break. 

 

And them holes are M8 not 10.

[miketomcat]

A tip for cleaning threads:

Use an old bolt of the correct size put a cut in it about 5-10mm long and 1-2mm deep along the length at the tip. Wined in and out the crud will fill the cut job done. To check you have the right thread compare diameter of the bolts then press the threaded part of each bolt together if they match (you will feel/see them rocking it not) job done just be careful some threads are the same on different diameter bolts.

Mike

[GW8IZR]

Yes, a hacksaw cut in a bolt does work very well, I have a couple of bits of stud with Dremel slots in them and turned down to fit in a battery drill, make excellent thread cleaners at circa zero cost.

[landroversforever]

I'd echo what Vulcan Bomber has said and say to go for a known brand like Dormer/SKF/Guhring, Presto and Volkel aren't bad either. The other thing with the sets is that there will always be ones you don't use which you've then wasted money on, I'd be more inclined to just buy the taps/dies as you need them.

I would normally use the plug tap as there's less chance of cross threading it if the threads are dodgy at the start of the hole than with a tapered 1st or 2nd tap.

On the other hand, if you're down in the Stanford area you're welcome to a cuppa and my taps?

[Peaklander]

Thanks for the advice everyone. I hate buying cheap but then i hate buying expensive and not making full use of something. Sounds like none of those sets are really the way to go. Perhaps as you say buying just the taps I need, when I need them would be a better way.

I like the slotted bolt idea and that would be a good approach for this particular task as I have some 8mm threaded rod (yes 8mm not 10mm thanks Vulcan) and although I don't have a dremel I do have some of those ultra thin cutting discs so a very careful use of the angle grinder might just do it.

Thanks for the offer Ross - that cuppa is most certainly on the list as B&P were here this summer so the next trip is our return. I might even look you up in the daytime too and revisit the old workplace 

[qwakers]

sealey ak3040 

 

absolutly excellent kit for the price none of that cheap garbage, doesnt have any bottom taps but you dont really need them most of the time for general rethreading or thread cleaning work. 

Edited November 15, 2016 by qwakers

[Bowie69]

Have to say, I bought a Sealey kit about 10 years ago, I still have it, the plastic box is rather battered but all the taps/dies are still there, and nothing broken....

For the money they are excellent, though of course nothing like a 'proper' make.

Halfords have them at a decent price, half that of the Sealey website: http://www.halfords.com/workshop-tools/tools/hand-tools/sealey-ak3040-tap-die-set-40-piece-split-dies-metric

[qwakers]

best price is on ebay at the moment £31

[Peaklander]

Well it's certainly tempting. Is it the Sealy brand that separates its quality from others at that sort of price such as the one I linked to at the top?

[qwakers]

not really, its more theyre well made and ive never managed to snap one.

[nickwilliams]

I'm local to you, Peaklander. I have more taps than you are ever likely to need. PM me if you want to borrow a few. 

[muddy]

I use one of these, yes they are the budget stuff but for thread chasing they are fine and the selection covers pretty much everything on a landrover and most agricultural stuff. once you have used it a handful of times buy a decent brand of the common taps if you feel the need, a bit of feel goes a long way.

https://www.ebay.co.uk/itm/281684033287 

 

snap on do some tap drivers in 3/8" flavour which are very very handy also.

 

will

[Peaklander]

1 hour ago, nickwilliams said:

I'm local to you, Peaklander. I have more taps than you are ever likely to need. PM me if you want to borrow a few. 

Hey that's nice of you, thanks Nick and I'll take you up on your kind offer 

 

Muddy that link doesn't lead to an item...

[muddy]

Hmmm strange it worked for me when I posted.....but doesn't work now.

 

ebay #281684033287

will.

[UdderlyOffroad]

9 hours ago, Peaklander said:

I like the slotted bolt idea and that would be a good approach for this particular task as I have some 8mm threaded rod (yes 8mm not 10mm thanks Vulcan) and although I don't have a dremel I do have some of those ultra thin cutting discs so a very careful use of the angle grinder might just do it.

You're actually better off using a hacksaw to cut the grooves, an angle grinder will tend to produce folded over edges, you want them as sharp as possible.

9 hours ago, Peaklander said:

Thanks for the advice everyone. I hate buying cheap but then i hate buying expensive and not making full use of something. Sounds like none of those sets are really the way to go. Perhaps as you say buying just the taps I need, when I need them would be a better way.

I started off with a cheapo Clarke set, which was a bit rubbish, but I was a poor student at the time and needs must - and for thread cleaning the 'cut grooves in a bolt' trick works very well.

When I got a proper job I was able to, um, acquire a few dormer taps from work.  They are like night and day, but the key thing with thread cutting is: take your time, and don't go in cock-eyed.

This 'vidjeo' on youtube explains the bolt trick

 

[Peaklander]

I really appreciate all the advice and I think for the particular job mentioned I'll try the slotted screw (using a hacksaw cut). I'll pay a visit to the White Peak and introduce myself to Nick and perhaps that Sealey set would be a good purchase if I do go for a 'full' set. It's amazing how the prices range from that very competitive eBay seller to whatever you want to pay really. 

[Troll Hunter]

Please, don't wait until you need a tap or die before you buy it.  You'll end up wasting hours, or days, after you find you need to clean a thread but don't have the correct tap or die.  And with the "standardisation" of threads found on Land Rovers and the various OEM suppliers bits, you'll soon appreciate the benefits of a full kit of metric and ASME threads. 

As UdderlyOffRoad said, take your time, and I also find that regular dosing with a light oil helps significantly.  As well as taps and dies I also use a set of thread files, for bolts only, of course.  I have both metric and ASME, with eight thread sizes on each double ended, square file.  These are often quicker to use than my taps and dies and provided the correct thread is used, they're virtually foolproof.

Mike

[HoSS]

forgive the colloquialism - but cheap taps are like cheap tarts - they just dont cut it, and they dont last until morning...

 

[Peaklander]

Just a quick muppet question about the action shot I posted at the top of the thread - what's actually being used here? The thread is being cleared and a cordless drill is being used but I presume that it's on ultra-slow so that the tap (or slotted screw?) is turning very slowly? If it was a tap and turning fast, wouldn't it pull into the hole too quickly and then spin and re-cut or something?

[HoSS]

1 hour ago, Peaklander said:

Just a quick muppet question about the action shot I posted at the top of the thread - what's actually being used here? The thread is being cleared and a cordless drill is being used but I presume that it's on ultra-slow so that the tap (or slotted screw?) is turning very slowly? If it was a tap and turning fast, wouldn't it pull into the hole too quickly and then spin and re-cut or something?

I wouldnt use a drill for that, the risk is breaking the tap. You can get away with it in Alu and thin steel.

 

[GW8IZR]

I use a drill often for stuff like that, I just gently nip tjhe chuck by hand and it slips if it grabs, I start threads the same way in the milling machine to keep them straight, turn it off and drop it in the hole then cut by hand.. The only time I break taps is doing small holes in copper by hand, I hate taping copper....

[HoSS]

17 hours ago, GW8IZR said:

I use a drill often for stuff like that, I just gently nip tjhe chuck by hand and it slips if it grabs, I start threads the same way in the milling machine to keep them straight, turn it off and drop it in the hole then cut by hand.. The only time I break taps is doing small holes in copper by hand, I hate taping copper....

Sure, but in a lathe or mill the tap is held perpendicular. A hand drill is not, thats the difference.
We have a lovely drill press with tapping function in the workshop, auto-reverses at a set depth, very useful when doing 10's of threads. But try that to anu depth with a hand drill and you would break taps.

[GW8IZR]

Yes I think we are at cross purpose here, the original pic was discussing using a battery drill to clear threads and I've been doing that as long as there have been battery drills, never broke a tap once.. now I possibly confused the situation by saying I often start a thread in the mill.

My mill isn't advanced enough to tap under power but starting threads and same in my little lathe, thats a different thing.

[Troll Hunter]

Slightly off topic, so please move if inappropriate, but while we're talking about drilling and tapping how do members start to drill a hole that is intentionally at an angle to the work piece surface?

Mike