Recommend a good quality tap and die set for model makers

[Tater]

I bought a cheap 64 piece set from HF and find that the dies do not let me thread small diameters with any precision. The dies cannot cut up to the inside shoulder and leave a large uncut area that makes threading bolts and precision valve fits impossible. (Yes I am flipping the die and making a final cut). I really think this is a limitation of the cheap Chinese dies, and I'm hoping there is an alternative besides cutting the threads on the lathe.

I'm looking for a metric and imperial combination set if possible.

Thank you for any advice.

 

[kvom]

My approach has been to buy individual taps and dies as I need them, and only use HSS rather than carbon steel.

 

[Blogwitch]

With reference to your cutting to a shoulder.

I always put an undercut at the shoulder, just like when single point threading and having a run out groove.

The easy way is to cut the thread with the die, then come in with a grooving tool (same as a parting tool, but a little thinner) and just cut the tapered threads at the shoulder down to thread root depth. Problem fixed.

At one time, by turning the die around, you could cut right to a shoulder, but it seems that dies nowadays (even the expensive carbon ones I use) have a lead in taper on both sides, the reverse being slightly shallower.
If I am doing a lot of threading to a shoulder, to save time by not putting an undercut on, I will buy a spare die and grind the reverse so that the taper has been removed completely.


John

 

[Tater]

Thanks Bogstandard - that has been my approach as well, cutting a little run out space with a 1/16 parting tool I've ground a little narrower just for this purpose. The trouble is that even on the shallow side of the die, the taper meets the shoulder before the last thread can be cut to the runout channel, and begins to cut (scrape actually) the outside edge of the piece. (In this case I'm making the little threaded valve fittings on the Elderberry launch engine.) My first project BTW...

I think your soultion of grinding the face of the die down a bit may be the best option. These are pretty cheap Chinese dies to begin with, so not much at risk.

I was just thinking that there might better, more precise dies that everyone else was using to do this kind of detail work - that I hadn't been clued in to.

 

[Blogwitch]

Tater,

Use the old trick of making fairly thick copper or ali washers, well annealed, and fit them between your parts. 1/16" to 3/32" thickness would be ideal, not only do they seal well, but look good to boot. They should take up where the taper is, or else, counterbore the female hole slightly.

John

 

[Tater]

Cheers John, I think I'll take your advice! I've been thinking about ways to make the little launch engine kit a bit prettier. So far I've decided to replace the cheap cylinder head screws(!) supplied with the kit, with my own threaded rod and bolts - blackened in oil (tip found here on the site) and nice copper washers would add a bit of style too.

 

[modelman1838]

Faced with this problem in the past I have tapped a hole in a small piece of 1/8 gauge plate and then cut one or two cutting faces with a rat tail needle file and then hardened and tempered. This does the job well, similar to the old die plates of yesteryear before stock dies as we know today.

Hugh

 

[maverick]

I've had good luck with a type of dies called acorn dies or spring dies.
They are used on turret lathes and screw machines, but work well
on engine lathes. Number 1 and number 2 sizes are shown, this is the holder
and die size, not thread size. They range from #2-56 to 3/8 or so.
These are Greenfield but IRCC they are available from Widell
Through MSC and Travers.

 

[user 284]

Tator,
Please don't take this as offensive as it's most likely going to sound like it is. It's certainly NOT directed towards yourself.

This forum is one of the better ones around. If it wasn't, I wouldn't spend as much time lurking here as I do. Personally, And many others including the editor of Model Engineer and Model Engineers Workshop will agree with this. In a private PM, David Clark agrees 100% with my following points. (Taps and Dies comments subtracted.)

Forums like this one and any other you'd care to name may have possibly neglected to provide some basic but inarguable information. A proper informational "sticky" type thread that does contain the majority of comman sense information would do far more than all the repetitive posts about the very same subject that gets brought up over and over again will ever do.

Cutting tools like taps and dies since you brought the topic up, Are the one single item where you do get exactly what your willing to pay for. High quality and very good and sharp cutting tools, Along with the word cheap is an oxymoron. And it is to be very blunt, An impossible to have combination. Believe me, I've wasted far too much money trying to get that combination to work only to finally realise it just isn't going to ever happen. Taps and dies are tooling where your specifically depending on them to provide a totally finished end result. Buying like I've done in the past with cheap taps and dies is now due to my experience a total waste of money unless your working on home garden equipment where good enough is actually good enough. After digging out a few broken off taps in some parts that had more than a few hours invested in them. I have without fail, And every single time, Very much wished that I'd paid what I should have for a quality tool to begin with. Yeah the very best threading tools built today can still be broken. But very good HSS threading tools that are actually properly heat treated, And built from high quality HSS, And then properly ground so that they are in fact sharp from the factory like they should be? They very rarely break. (so far for me never.) I tried for years to just get by with cheap threading tools. You or anyone else reading this may think I'm full of it. Fair enough, But at least do make it fair enough. Order in a a top quality tap in a size you already own. Drill two tap drill holes in the same material and then use both taps. You can figure out the rest on your own. I really didn't know what a top quality tap or die could do until I tried some of the ones built by OSG.

My whole point about this is that ALL the forums and ALL the hobbiest type magazines have in a way failed to provide some of the very basic information that would in fact save the readers and members a hell of a lot of money if they just had that information available. It's completely moronic for each one of us to learn by trial and error the exact same thing over and over.

I'll also mention that for anyone who disagrees with my above points? They can save themselves a hell of a lot of effort. You can't and will never ever change my opinions. They really have cost me far too much to learn the hard way. I do know now what works and what doesn't. So if you can't quote Albert Einstein about the relative theory of cheap taps and dies? I can't see where I'll pay much attention.

Pete

 

[Blogwitch]

Unfortunately Pete, some people will disagree with some of your points raised. Myself being one of them.

Having now nearly 50 years under my belt (I started off very early in life), and have been threading for at least 45 of those, I think I know how things should be done, but I NEVER force my views onto other people, I only suggest that it is my way of doing things and people can read into that however they want to. They can follow my lead or not, I can only make suggestions.

Your comment about only using the best HSS tooling is really annoying to me, purely because, unless I am doing production work, where I will throw away a bulk purchased HSS (but still expensive) tap or die at the first sign of a squeak, I swear by carbon tooling. In fact tooling supplied by Tap & Die which are what they call HQS steel.

I have carbon tooling sets made by Presto going back over 30 years and they still cut as well as the first day that I bought them. I do resharpen them myself by hand BTW.

In my own opinion, correctly made carbon T & D's far outlast HSS ones many times over, and cut a much cleaner thread in most materials, especially stainless, but that is only my opinion, and mine alone.

It is always up to the person doing the job that has to take into account what he has need for.

Not everyone can afford the nearly 1000 pounds that I paid renewing and updating all my carbon T & D's sets a short while ago, some people only have a few bucks they can spare, so they HAVE to go with what they can afford, no matter what information we can impart to them.

All we experienced people can do is suggest, NOT TELL people how they can solve a problem.

No offence suggested.


John

 

[Tater]

Pete,

I appreciate your candor. In fact you are confirming my own belief that cheap tools are a false economy. In most cases, I try to buy the best I can afford. However, I have to say that in my short experience as a beginner machinist, I have been impressed with how much functionality one can get from what are really cheap, Chinese tools. Granted, they take an immense effort in set up, and really require the best cutting tools one can get - in the case of my mini lathe that's nothing more than carefully ground HSS cutting bits, which I have become pretty skilled at making myself in a short period of time.

But, I recognize that there are always going to be those tools, (and procedures) where no shortcuts or cheap options are truly viable. I suspect that taps and dies are in that category, and that's what prompted my post. I was looking for some pointers on better tooling than the cheap combination set I bought from Grizzly - while it's supposed to be made from HSS, the quality of manufacture is clearly not that great.

I can't afford to go all the way to the very best taps and dies, where $50 or more is required for a single 10-24 die. I am looking for something more in the $20-30 range however, which I would hope to be a vast improvement over my current kit. Still open to suggestions here.

Anyway, I have learned a lot more on this thread than what I thought I was asking for. To me that's also the incredible value of a forum like this, where members of vast and varied experience share ideas and points of view (like your own) that may be tangential to the topic, but of tremendous value nonetheless. Thanks for sharing your experience.

 

[Mainer]

If you can find truly good quality carbon steel dies they should be as good or better than HSS. HSS's advantage is "high red hardness." It can get hot and not lose its hardness. In a die slathered with cutting oil, that trait is totally irrelevant. Carbon steel, properly tempered, can be harder, tougher, and sharpened to a keener edge than HSS. But the problem these days is finding GOOD carbon steel dies.

 

[ShedBoy]

I bought a set of Garvin taps and dies on a chance and so far I have not been happy with them. They are good for aluminium and brass but are iffy when it comes to steel (2 x broken 4mm taps with 3.5mm holes, which is 0.2mm extra), one has been turfed due to bits breaking off or rounding over. I only ever thread with the smallest T handle it will fit inot with the least leverage and try to support the T handle from above to keep square. I am replacing with known quality brands like Sutton, Dorma and a new one to me which is going well Goliath. It is worth it in the long run I have two parts with lots of time in them and also a broken tap which will need an EDM to remove. My two cents worth.

Brock

 

[Propforward]

Sorry to resurrect an older thread - but I am looking to obtain some of the smaller taps needed to make my first model engine. Did a bit of a search but haven't found a good source, so I was going to just go with McMaster Carr, unless anyone has a really good source to recommend?

My experience with McMaster is that they may not be cheapest, but in general sell good quality items.

EDIT: Heh. A read back through the thread reveals Travers as a source

www.travers.com

I've never used them before - generally considered OK?

 

[Herbiev]

I found these tungsten alloy ones very good.
http://www.myshopping.com.au/ZM--12..._IN_METAL_CARRY_CASE_TQ7023_7023_METRIC_45_PC

 

[kuhncw]

My experience with McMaster is that they may not be cheapest, but in general sell good quality items.

EDIT: Heh. A read back through the thread reveals Travers as a source

www.travers.com

I've never used them before - generally considered OK?

*****************

I've bought items from Travers over the years and always had good service. I think Enco, MSC, Travers, McMaster, etc are all good sources for small taps.

Chuck

 

[Propforward]

Thanks guys!

 

[lensman57]

I bought a cheap 64 piece set from HF and find that the dies do not let me thread small diameters with any precision. The dies cannot cut up to the inside shoulder and leave a large uncut area that makes threading bolts and precision valve fits impossible. (Yes I am flipping the die and making a final cut). I really think this is a limitation of the cheap Chinese dies, and I'm hoping there is an alternative besides cutting the threads on the lathe.

I'm looking for a metric and imperial combination set if possible.

Thank you for any advice.

Hi,

I am a bit late in the debate but when I started this hobby about 18 months ago I had to ask the same question. My advice is to not bother with cheap sets and buy as the engine plan calls for. Most model engine designs require only a couple of sizes of taps or die and you'd find that these sizes are common amongst engine designs. There is no reason that a metric tap could not be replaced with an imperial one of close size or vice versa unless you are building from castings. I regularly replace 2-56 with M2 and so on in my builds.

Regards,

A.G