I Need a Custom Thread Tap - Shop Made Tap

G'day everyone,
I think there is a time where every hobby machinist will find that they need to make a custom thread tap, and that day has come for me. I need a large M20 tap with a fine pitch, much finer than the ones commonly sold. M20 usually comes with a 2.5 or if you are lucky 1.5mm pitches, but for an upcoming project, space is tight, and I need a tap with fine threads.
Now M20x1.0 isn't exactly an exotic thread (such as M5.5 x 0.5 or M7.9 x 0.6 which I have taps for) and they are sold online. Roughly $20 for a Chinese Tap or $50 plus shipping for a German made one.
However it is a lot to pay for a tool that I am only going to use once, so I thought it would be a nice challenge to try and make it myself.
I have made one or two before (M7.5x0.7) but none which were designed to cut steel. So I'll need to be very careful about making this, and including the proper cutting geometry and relief angles.
I will also need to carburize the steel in order to harden it. I hope you enjoy the video.
#machining #DIY
Custom Tap Build
I need a custom tap
M20 Tap
M20 x 1.0 Thread tap
Timestamps
0:00 - Introduction
2:20 - Cutting Geometry
4:20 - Lathe Machining
7:11 - Milling The Shank And Flutes
10:52 - Heat Treatment
14:44 - Grinding Relief and Testing

[@rednwhitecooper]

Don’t underestimate the power of a bolt with flutes cut into it. They make the best diy thread chasers in a pinch.

[@travisfabel8040]

Put the bolt in your vise and use a cut off wheel in an angle grinder to make a slot through the threads. Chuck the bolt up in a drill and hold some Emery cloth to it so it becomes a bit undersized and run it through to clean the threads of whatever grit and oil and whatever gunk.. I've done this for years with old automotive parts when I can't thread stuff in because of how dirty they are and I'm limited in ways to clean the area.

[@breadlowry]

​@travisfabel8040 oh yeah....you mean just like he shows in the video?

[@travisfabel8040]

@@breadlowry no. You have to read past the first sentence of my post. You do what he did there, and then you turn it under size and then... Instead of using it to cut threads like he's using there, you use it to clean existing threads and break out the dirt and gunk and stuff that accumulates in old automotive engines/chassis.

[@MegaDada1995]

@@travisfabel8040 That's the way! I always use that if I had to make any machining operations near/around a tapped hole, cleans up any burs, chips and gunk that may have gotten into the hole!

[@Sodabowski]

Also works great with wood screws to drill/pre-tap a hole in a splintery wood. Some high-quality wood screws over here (France) actually have a flute cut at their tip to help with that.

[@randyshoquist7726]

Only the first few teeth actually cut, so only they need relief. Beyond that, the teeth which don't cut should have rake and sharp edges on both the front and back, so that chips are directed back into the gullets when backing the tap out. By grinding back all the teeth, you've formed gaps where chips can get wedged, potentially damaging your newly cut threads. Be sure you thoroughly clean the chips out before backing the tap out to mitigate that risk.

[@user-tq2lf1zx8v]

👏

[@user-tq2lf1zx8v]

I was looking for this comment, thanks. greetings from Ukraine

[@artisanmakes]

Interesting, the machinery’s handbook seems to be absent on that detail

[@chadpendt2863]

@@artisanmakes the handbook seems to omit alot of things that *should* be common knowlege but are often easy to overlook if youre not specifically thinking about it in the moment.

[@aiTheVulture]

​@@artisanmakes cheked textbook for university students (USSR 1939), it mention *cutting* and *calibration* teeths with different geomentry, which can or cannot be present on same tool depending on tool material(carbide/steel) and aplication(manual/semi- fullyautomatic machines). Mb ur book on more specific topic.

[@victorbruun]

i like how you've adopted a little ToT in your camera work lately. you do it well.

[@Barty.Crowell]

Plot twist: This is Tony's side channel and he hired a different narrator so we hopefully wouldn't notice

[@daveymathews878]

I work in a machine tool repair shop, and that bolt with slots trick is something we do a lot, mostly in steel. Better to try and use that to chase/clean up a threaded hole and break it off than a tap . Works great imo

[@tnor90]

Great DIY video for making unique taps. However for base material I would choose Böhler K110 - 1.2379 - AISI D2 cold work tool steel for this project, as this steel does not require rapid cooling for hardening, can be cooled down in air with the furnace and it will still go over 58HRC. We made a few special tools from this material (special taps, bending tools, etc.) and it's very easy to machine. The only important thing is the tempering after hardening, we used a standard kitchen oven, where we put the parts for a few hours in max. temperature (around 250 °C), then they will be not so brittle then.

[@artisanmakes]

The lengths I’ve had to go to to get anything other than W1 or O1 from local suppliers. Carburised steel really isn’t my first choice given it’s low hardenability. I’ve always wondered if people made taps from D2 given its reputation as a good cold working steel. Now I know.

[@smashyrashy]

​@artisanmakes maybe give up on trying local because for most things it's not realistic

[@21gioni]

I’m was surprised that you succeeded.

[@artisanmakes]

Yeah I have better luck getting exotic tool steels imported from Europe. Had to get a plate of S4 tool steel from England. Shipping is quite expensive unfortunately

[@standardtoaster10000]

@@artisanmakes That's unfortunate and surprising, over here in NZ I can pretty easily get most of the A/D/O tool steels as well as the Böhler range (and other special stuff like 6AL4V can be special ordered in). Maybe you need to branch out and look at suppliers outside of your locale.

[@takoslvt]

I'm willing to bet that DIY bolt tap would have worked in wood and aluminum even without the flutes.

[@ajs222222]

With a good squeak in the wood. Ha

[@CatNolara]

Nicely done. Btw. from what I've seen taps usually only have a relief cut into the tip, since that's where the cutting is happening. The untapered part of the tap is mostly just for guiding it. Also you could have set up something with the dividing head and the grinding wheel in the mill to sharpen all the edges properly, I tried sharpening cutters like you did by hand, but the risk of accidentally rolling over the cutting edge and thereby ruining it is too high.

[@jamesschoneman4461]

I see you're channeling your inner TOT I love it!

[@jasongarland3165]

Nicely done! The only suggestion I would offer is, should make more taps in the future, stamp the die size and thread pitch on the shank for quick reference in the future. Otherwise you may end up with a box of unmarked taps.

[@ErikBongers]

Your tap and die inventory is surprisingly similar to mine. I have the same grey box with metric taps. (I believe the site labeled it as a "pro" set, which I'm sure it is). And in addition I have a non standard M15X.75 tap and die.

[@jameshisself9324]

I sure wish one of you had told us the brand or shown the label! They look decent.

[@sethh8892]

​@@jameshisself9324he clearly shows the brand it's a Frost 40-piece tap and die set. Never heard of that brand but I'm sure it's the same as other brands with a diferent label on the box. Most tools come from the same major manufacturers... there's only a few that are outliers like Snap-on that actually manufacture their own tools.

[@joshclark44]

I was worried youd forget about the cutting geometry on the tops of the threads, but then i saw you grind it down and that was a relief

[@avelkm]

😂

[@LordPhobos6502]

"That's right, they're designed to break off in your workpiece!" Truer words were never spoken! :P

[@umahunter]

Quick tip for saving aluminum parts if your part is aluminum and you break off a steel tap that there is no other way to get out you can submerge it in water mixed with alum powder used for brine making the alum will slowly dissolve the steel and leave the aluminum alone you can usually find alum powder in the spice section at the grocery store it takes a lil bit but can save a part with lots of hours in it there's some more in depth videos on it on here 👍👍👍

[@Horus9339]

Fantastic work Sir, so much information and skill shared to make a tool. Thank you for sharing your time.

[@Cjarka_]

So I may have forgot my tap at home and needed it at the workshop which is about a 20 minutes drive. No way I am going home just to grab a tap xD So I grabbed a 12.9 strength M4 bolt, ground a single flute in it and a lead angle, tested it out and in aluminium it made usable threads. I just needed to hold cable chains in place so the thread didn't need to be the strongest anyways

[@y2ksw1]

One of the most appreciated skills I had, was tool making. It needs the persistence of a maniac 😅. It was the only way to get some relief from my shop partners who found in me the perfect prank victim. My special tool box was out of reach and when they needed some, they knew that a prank would lock tools away for a long time 😂. You should start making tools and sell them. Many people will appreciate and do not pretend to get perfect tools. While starting and testing new ways, you will become better. Over time, tool makers are the most payed shops. Once you started, your name will precede you 😊

[@artisanmakes]

You can definitely get a surface flat, but I am not sure how well that method can take two surfaces to be parallel to each other

[@edsmachine93]

Nice work. I think that it came out great. Thanks for sharing the process. 👍

[@bostedtap8399]

Nicely done, very interesting to see pack hardening. Thanks for sharing

[@dougmac777]

Fantastic job!! So complicated and very well explained...got my subscription! Thanks!

[@J.C...]

The last one I had to buy was specific to the cylinder head bolts on this one specific engine and maybe a few others. Very uncommon. So much, in fact, that the only place that sells one is the automotive performance parts stores. There is no other bolt anywhere with this weird thread pitch except for Chevy engines. The kicker is it wasn't to cut threads. It was a thread cleaning tap. That's what most people try to make when they cut slots in a bolt. The thing is that thread cleaning/chasing taps have threads with a different geometry than a standard bolt so that they clean the entire threading area and not just some of it like a slotted bolt does. But most people either don't get it or don't care. That cylinder head bolt cleaning tap was essential for anytime you remove the head on a GM Atlas engine and maybe LS1s? The bolts already break when you remove them so having the threads surgically clean is the best you could get.

[@alfabethev2.074]

Fantastic ! Very enjoyable to watch👍🏻

[@jonathonhanks.cmdreaglejon5993]

Great work mate I enjoy watching your videos greatly .

[@CoolIdeasDIY-qv1nz]

Great job friend!

[@howder1951]

Great video, I have tried this myself and found similar results. Nice work on trying to produce some relief which I believe is the answer to getting pro-like taps in the home shop.Enjoyed, cheers!

[@nuneke0]

Machining is amazing. I wish YT-channels like yours were around when I made my, in hindsight regrettable, career choice 20 years ago. 👍

[@allanpowell7208]

Good stuff as usual. A couple of years ago I bought a job lot of Ebay UK taps and they have been lifesavers in each case I resorted to them. I got a jackpot lot at a local recycling depot, mixed imperial and metric too. Your video shows the last ditch option and very useful it is too for those with no metalworking experience. Cheers.

[@johngibson3837]

Nice work mate i like your style, like has been said the cut bolt is good/reasonable for chasing. Good work and thanks

[@ryanweaver4637]

I absolutely love your vids your description of everything is so well said and you always toss little joke in here and there. You do a very good job at lathe and very helpful. I am new to getting myself a little 8x14. And have been watching all sorts of vids trying to learn and you have been by far the best one. Just thought you should know that and I would like to thank you i have learned a good bit. cheers!

[@leadgindairy3709]

You would really like Inheritance Machining too, I bet. I very much like them both.

[@leadgindairy3709]

And Blondihacks too

[@jimzivny1554]

Beautiful job

[@james.d.8044]

wow impressive job it looks great !!

[@allengentz7572]

Thanks for a great tutorial I feel more confident to try also

[@homemadetools]

Nice work as always. We shared this video on our homemade tools forum this week 😎

[@mulletmaster1236]

When i was an equipment mechanic i only had taps up to 1/2" plus a few randoms here and there, i never tapped threads but i did clean threads with a bolt with flutes many a time

[@russtuff]

That came out great!

[@mazchen]

Not entirely sure whether I'd agree to 1-2 days of work beeing cheaper than 50 bucks but the result looks great and works and I guess you've (and your viewers as well) learned a lot, and that's all that counts!

[@markfryer9880]

Well we got another video out of his need for a special size tap, so we shouldn't complain. 😊

[@artisanmakes]

Well this isn’t a job for me, just a hobby so I don’t typically factor that in. If this was a job shop you’d need to account for time

[@Mad.Man.Marine]

It’s not the wrong tool of it gets the job done!!! Nice work man!!

[@jlinkels]

Nice work! And great recording without music, no elevated playback and machine sounds included.

[@Bob_Adkins]

Great work on the hardening. Case-hardened taps are not as likely to snap off as alloy taps.

[@DK-vx1zc]

very Nicely done !

[@redgum1340]

Good on ya mate, looks good

[@johannriedlberger4390]

My favorite taps are spiral flute machine taps. I got them very cheap from China as a set M3 to M12. I use them in the lathe, drill press,milling machine and by hand. They work great in steel, aluminium and stainless. I don't know a brand but they are complete black.

[@chotuusian4127]

Good work👍

[@cjm5002]

I'm genuinely impressed. Aside from the relief that looks like a commercial tap! Nice stuff, man.

[@artisanmakes]

Cheers. One day I’ll get a cnc grinder and we can get a perfect curved relief

[@Dennis-uc2gm]

Your Tap looks pretty good to me. I'm always running into some odd ball non standard bolt that I've got to run a tap for at times. I have used the cheap method if its just soft metal I'm working with.

[@aljosapristovsek8240]

You could mill those 5 flutes into a higher quality screw and then grind the cone .. it would take much less time. But on the cone you must add a clearance angle, this will make your tap more effective.

[@troy_neilson]

Another great video, mate...

[@Smallathe]

Nice!!! Very impressive...

[@anthonybernstein9698]

As somebody who has never done any metal or engineering work I find your work really fascinating. The only thing I did not understand was if you needed this tool for your job, or is this your hobby. Rather than pay 50 to 60 dollars for 2 days work plus materials the choice was to make the thing.

[@artisanmakes]

No this is not my job

[@the4thj]

I am always faced with...what is the right threat for the right job.

[@Hansca]

Fascinating!

[@philliplucion4262]

Good to see a new vid bro

[@sethh8892]

Best way to prevent caps from breaking is to buy a very high end set of taps. They break the bank but they won't break your workpiece. They also give you that peace of mind not having to worry about things like this. Not everyone has a bunch of money to throw at expensive tools, same here, but I still manage. I try and only buy the best of the best when available. I never have to worry about my tools breaking, so I am always confident in my work.

[@robertwalker7457]

Great work thanks.

[@piteralvarado1028]

Muy bien trabajo amigo

[@Climber31Gaming]

You had me at the thumbnail

[@dayradebaugh]

Nice video!

[@KathrynLiz1]

Nice job...

[@NicksStuff]

First time I see someone make a tap on KZbin. I don't know why it had never occurred to me you could do it *reasonably* simply

[@Dreddip]

Lmao! When you said "some of you already know what these tools are used for" I said to myself "taps that can break off and screw your whole part" and then you said basically the same thing I LOL'd!

[@TheDistur]

congrats on the tap

[@MrKyltpzyxm]

I'm watching this video because the thumbnail image joke made me laugh. Off to a good start before I even press play.

[@kevinmartin7760]

The geometry on your tap when you first tried it actually has a slight negative relief because as you turn the tap it advances into the cut thread and the cone shape of the flat tops of the cutting teeth increases in diameter and wedges tight. The effect is only slight but is definitely non-zero. The negative relief angle can be calculated from the thread pitch, diameter, and cone taper angle. I need to get/make a 3/16-40 55 degree tap, just a shade smaller than #10-40 which is itself non-standard but available (with 60 degree angle). This seems much more challenging than the relatively monster-sized tap you make here. On the other hand, I only need it to chase out remnants of drilled-out brass screws in hardened steel so just the gashed-bolt geometry without hardening might suffice.

[@wizrom3046]

I would have made the angled part (lead in) much longer so the cutting is spread over many more turns, that would also reduce cutting force. Your hardening system is getting quite refined. 👍

[@douglaspierce7031]

Commercial taps are typically form relieved and have a slight back taper after the first couple threads past the lead.

[@artisanmakes]

That could well be true, seems the machinery’s handbook is absent on that detail

[@HanMoP]

clean hour tools.

[@lolcec81]

Комментарий в поддержку канала и ролика, а также труда мастера

[@davidiansykes]

great job and the main thing is it works

[@flatmoon6359]

Drilling the correct drill size hole in the first place helps. See people drill holes far too big and small so many times.

[@01thomasss]

Hi I would like to see project where you use the tools that you make. And your other projects too.

[@hardwareful]

I imagine the threads would look even better with a lick of a thread chaser file.

[@Dibulok]

Nice video thanks! 😁 I have always been told to use methanol alchohol when drilling and tapping aluminium.

[@joesilvasr9733]

VERY cool!

[@rsmaster5637]

Great work .. if you consider the material , worktime , hardening etc in .. then 60 bucks is quite cheap for a store bought tool.

[@keithammleter3824]

two things considerably reduce the chance of breaking taps and ruining projects:- a) use spiral flute taps meant for factory production; b) use a guide to ensure you are inserting the tap coaxial with the hole - do not relay on eye judgement.

[@mattym8]

Could always put Lube on that bolt before spinning it into aluminum at 20,000rpm

[@buysncharge]

Gotta pay for the nice taps. I learned the hard way myself

[@mrcpu9999]

did the tap possibly bend/distort after quenching? Be curious what the runout was. But it was a great video on how to make a one-off tool. Reminds me of TOT's.

[@kosir1234]

That is how i made my tap, but it was some weird imperial, like 2 and 1/4 inch and weird thread pitch. I also started with steel that is intended to be hardened tho :D

[@Rockport1911]

2:55 I did that few times in the past. Works in aluminium but iam not coming here to see hackjobs :) As always its great to see someone making his own tools :)

[@zaphod_beeblerox]

awesome!

[@greggroos2271]

Hope it's OK if I quote you? "Little bit less sophisticated and using the wrong tool for the job" pretty much describes everything I do:) Thanks for making this, and great info in the comments.

[@rx323bug]

Could you use a store bought tap with a 1mm thread pitch as a cutting tool to cut teeth onto a tap blank? If you set it up right in the offset you could dial in some relief as you cut the threads into the blank?

[@jfa3019]

If you haven't tried spiral fluted taps, give them a try for the most common threads you use they are so much better than straight flute taps

[@cybercapri]

There are many reasons to cut threads into wood; just depends on the project at hand. Some even go as far as to cut threads and use a threaded insert to ensure the item is secure. I guess it's up to each and how to curb one's OCD when it comes to threads as to how far they'd be willing to go... Cheer's...

[@artisanmakes]

I’m aware of that I’m quite sure that they are a different thread form made for wood no?

[@cybercapri]

@@artisanmakes Threading wood typically works best with a more course thread vs a fine thread if that's what you mean by different. My comment wasn't about the size so much as the actual event of threading wood is more common that you said. You seemed to indicate that threading wood wasn't common or did I misunderstand you?

[@artisanmakes]

Well no I said threading wood with machine screw threads

[@artisanmakes]

I just had a quick recap and it certainly looks to be different thread standards for wood. Much coarser than what youd use for metal.

[@CMAenergy]

Very well done, But would like to know how it would cut in steel

[@johnrussell6620]

How about one of those $20 Chinese 1000W induction heaters for the 2nd hardening+quenching part of the job? Gets to glowing hot in 10 seconds. You could even possibly do it inside a glass test tube with some additional carbon material to really help those cutting teeth stay sharp.

[@nodriveknowitall702]

What's the thought process on your order of operation at the 2:10 mark? I'd generally center drill while I've still got the stock choked up in the vice. Honestly curious if there is something I'm missing.

[@WireWeHere]

A taper to share the depth of tooth cutting load is available via grinding stone too. Kind of you to share a carbon recipe. I learned at a young age what beer was really good for, in exchange for recipes.

[@ianbertenshaw4350]

I got rid of the frost set - nothing but grief from those ! You can get all sorts of weird taps and dies from LPR toolmakers , mostly carbon steel but they also do HSS . I got all my BA and ME sets from them and have had zero issues with them. These days I do everything in metric.

[@mikekuschka998]

I needed a m10x1.0 helicoil in a pinch. I just put in a helicoil for m10x1.25. Needed to repair pulled threads on a 2013 Audi R8 oil pump. A replacement was $2,000 USD.

[@scaler1179]

If you need to cut a relief into your tap next time. Try using a drill press with a mill table. Saves the cleaning process. Drill presses don't care about grit as much.

[@payron805]

honestly i just clic and like cause of the perfect thumbnail lol

[@Anthony-uz5tj]

when i break a tap its a nightmare depending on how much time i put into the part on the cnc is how i would decide cuz if its something i put hours into im using a carbide endmill and milling that tap rewelding the hole and then trying again

[@cookadam98]

great video. what brand is the set of metric taps and dies in the metal case?

[@Impuritan1]

If it breaks off in aluminum, you can dissolve the tap out with nitric acid and it won’t mess up the aluminum.

[@a0cdhd]

Saw somebody coat steel to be hardened in a thick plaster of flour and water. Dunno if he added sodium carbonate to it or not. He then sealed the thing in pottery clay before firing it. Seemed to work. Might be worth a go.

[@Zoombinis4life]

Have you ever tried using Cherry Red hardening compound? Works great for blacksmith tooling hardening for me, might not be powerful enough for actual machining.

[@rickpalechuk4411]

But the main reason is it's great content for the channel Cheers

[@rusticagenerica]

What do you do with all the metal bits that fall when you use the lathe?

[@travisfabel8040]

If this is for a project you're doing next week, shouldn't this be marked as side project 1??