Making a Custom Tap on the Proxxon PD 250/e Lathe

Making a tap is well within the reach of a home machinist, and I needed a very unusual tap to try and repair my G Boley watchmakers lathe. After watching a few other KZbinrs' videos on the topic, I jumped in and made a tool which successfully cuts a thread.
The thread in question is a left hand 4mm by 0.6mm pitch with a 55 degree angle. It predates most modern thread standards, and is not compatible with any older standards I can find. This video contains my first attempts at a number of skills, including precise thread measurement, heat treating steel, and grinding.
This is my entry for Emmas Spareroom Machineshop Toolmaking Competition. Check out her channel here:
/ @emmaritson
#toolmakingcompetition2019 #whenhellfreezesover
The links below will financially support this channel if you use them to buy stuff:
Machines:
Proxxon PD 250/e Lathe (24002) - ebay.to/2GdQ9Tg
Proxxon FF 230 Milling Machine - ebay.to/2YSDxIl
Chronos PP-U3 Tool and Cutter Grinder - ebay.to/2XN1OmQ
Universal Bevel Protractor - ebay.to/2LnHJwM
Tools:
Universal Bevel Protractor - bit.ly/33MhDZp
External Threading Tool - bit.ly/32sOked
Thread Gauge - bit.ly/2p28ywK
55 degree Threading Inserts - bit.ly/33NS6za
Triangular Needle File (part of a set) - bit.ly/2BrXlZ7
DCMT External Lathe Tool - bit.ly/2oOVwD2
ER32 Hex Collet Block - bit.ly/2BvET1U
ER32 Metric Collets - bit.ly/2J6XTI9
1.5mm Solid Carbide Ball Nose End Mill - bit.ly/2P4kh8N
10mm Solid Carbide Square Nose End Mill - bit.ly/2MXGIK9
MAP/Pro Gas Cylinder - ebay.to/2VV90ZY
Pizza Oven Bricks - ebay.to/2BpDb1Y
Materials:
BS1407 Silver Steel, 5mm precision ground round bar - ebay.to/2LnNJFA
Brass, 4mm round bar - ebay.to/32vHc1d
Music:
Easy Lemon by Kevin MacLeod is licensed under a Creative Commons Attribution license (creativecommons.org/licenses/...)
Source: incompetech.com/music/royalty-...
Artist: incompetech.com/

[@CaptainXanax]

In micromechanics we were taught that the first quench after heating should be in motor oil as water will steam when you put the piece in and you can get uneven hardening. We did oil, then water was mostly used to clean off the boric acid. Your setup is exactly what we used in watchmaking school, down to the annoying wire baskets.

[@AdventureswithaVerySmallLathe]

The quench medium depends on the grade of steel. In this video I used BS1407 Silver Steel, and the data sheet specified quenching in water. Other steel grades like EN19 / 4140 specify oil. I think most of my information on home heat treatment came from watching Clickspring, and I believe he learned much of his work from horology books, so it makes sense that some of what I did is similar to the process taught in watchmaking school.

[@DieTabbi]

All these prof. Mechanics have my deepest respect. Learned a lot in my study 40 years ago from a master. I thought wow these man has real knowledge ans I go only study. I fear that we loose the knowledge by computer cnc and lathe etc. Does young people learn to recognize metal by sparks ?

[@lorenkuhn3806]

This video is so perfect. Every minute there is something to learn while it has a comfortable pace. Everything is well explained, nothing seems to be left out. Errors are shown and explained, common mistakes are hinted at to be researched by yourself without distracting form the topic at hand. Well done!

[@AdventureswithaVerySmallLathe]

Thanks, good to know it is appreciated. :)

[@kevinbyrne4538]

Very nice presentation: the narration was clear and concise, and the video and editing (with the small exception that you mentioned) was very well done.

[@joshua43214]

I made a hob a while ago to cut a custom sized wheel for a worm drive for another project. A few things I learned from that project: Hardening burns off the sharp cutting edges, they should be ground after hardening. No need to harden the tap for soft materials. My wheel was made from aluminum, and plain A2 tool steel was hard enough to make several wheels with no signs of wear. If you are taping aluminum or brass, hardening just makes your life more difficult. I milled the relief at the same time I milled the flutes. I used a dividing head to accurately mill a 5 degree relief, but this could be done with small creativity with your collet blocks as well. Also, the tip angle of a tap depends on the type and pitch. 6 threads of lead is about right for a starter tap, a conventional tap will have about 3 threads of lead, and a bottoming tap about 1 thread. Very well done BTW.

[@sultanabran1]

as someone who has no manual skill, i find your work therapeautic and fascinating. thanks very much.

[@tannertrachsel1216]

Great job on working through new ideas and plans, i just stumbled upon your channel and i find this video very enjoyable and calming. keep up your great work .

[@multiSamP23]

I found this a fascinating video to watch. I am not an metal engineer, but I am a good mathematician. My only experience with this type of work is some 40 years ago in high school, where I made a tap wrench. I remember well the time it took me! I found your commentary very helpful in explaining what was happening. You measured with care and got a reasonable result for all the care and effort you applied to the job.

[@icanfixanything4u2]

Thank you for your insights i found it informative and satisfying to watch. your voice tone is also good and not monotone witch is a good thing,it keeps the watcher interested and not falling asleep.

[@bigmikeh5827]

Great job on the vid. Very nice work. I have my mini machine shop in my garage. Love being able to make things that others cannot. Keep the vids coming.

[@tdg911]

people never cease to amaze me. Well done!

[@TONYJUD57]

Wow! You'r never too old to learn a new trick or two. Cheers for that.

[@johnbeer4963]

I really like the concise way you explain why you did each step

[@1959rossco]

The incredible cleverness of some people always amazes me you are one of those people

[@titandominik5427]

I know im randomly asking but does anyone know a way to log back into an instagram account..? I was dumb forgot my account password. I love any assistance you can give me

[@deankorbin5640]

@Titan Dominik instablaster ;)

[@titandominik5427]

@Dean Korbin Thanks for your reply. I got to the site on google and im in the hacking process now. I see it takes a while so I will get back to you later with my results.

[@titandominik5427]

@Dean Korbin It worked and I now got access to my account again. Im so happy! Thanks so much you saved my account :D

[@deankorbin5640]

@Titan Dominik glad I could help :D

[@TungstenCarbideTempe]

Very nice video. Great scenery and outstanding deep voice narration. My 2cents: when it comes to tempering, for me, it works a lot better if you slightly polish/clean the part. It makes it way easier to see the temper colors. You dont have clean the whole part, you just want to make sure your part tempers evenly, so a few spots is enough.

[@txd]

Hello. Thank you for the nice video. I really like your editing and naration. Very enjoyable.

[@alexhawes6690]

I find this video very relaxing,you're like the Bob Ross of engineering. Subbed.

[@Syncopia]

This is spot on. I could listen to this man speak for hours.

[@GpunktHartman]

So i think : a perfek job ! Now the question: did you produce & sell this watchmakerlathe sparepart ? Exactly this part a friend of my need this ...

[@koehlerrk1]

A quick tip to help with the thread wires. A dab of grease on the threads will help make the wires stick to the part. Just a bit of wisdom shared with me from an old machinist.

[@AdventureswithaVerySmallLathe]

Thanks for the tip!

[@dikkybee]

Or just hold the wires vertically from above and the mic will hold then in place.

[@colincreedtattoomachines]

Nice to see you back with another terrific video, Well done!! Always interesting seeing how you tackle items like this with the Proxxon's as well as the extra tooling needed to accomplish it. Would also be interested in knowing more about the special Machinist Jack as well as your new D-bit Grinder too. Good Luck with your entry into Emma's Competition. regards Colin

[@AdventureswithaVerySmallLathe]

Really glad you enjoyed in Colin! Thanks for being such a dedicated viewer. :)

[@franzotto448]

Mein Sohn wird dieses Video lieben Danke fürs hochladen 👍

[@Razuliann]

I learned something new today. Thank you for the video!

[@CaptainSwoop]

You're a very clever fellow and a quality video producer. I enjoyed the presentation ... and learned something. Thanks.

[@stanervin6108]

Sounds like a Whitworth special. Seriously! Not unheard of

[@maciekm7953]

I came, I saw, I subscribed. What an great video and the whole channel looks to be brilliant. Thank You

[@twotone3070]

Veni, vidi, subscripta. Ego quoque.

[@Just1GuyMetalworks]

Awesome! A very enjoyable video 😊. Kinda feels like a nature documentary, like watching a machinist in his natural environment with their knowledge 😁.

[@AdventureswithaVerySmallLathe]

Thanks! Clearly I need to channel my inner David Attenborough when making these videos. :)

[@Just1GuyMetalworks]

@@AdventureswithaVerySmallLathe nah, you got him beat 🤣.

[@johnsolimine1164]

Nicely thought out and described. You're a born educator. Thank You

[@bencebabar610]

I see others have warned you about the unnecessity of quenching when it comes to tempering and I'm sure you already know the reasons as well. Another thing you might consider is the location of the tempering. As you said, the purpose of tempering is to decrease the brittleness of the material and make it tougher to avoid stress-induced cracking. These cracks always start at sharp and changing geometries like shaft shoulders and thread roots. If you look at broken taps, they usually break at the upper section of the threads where stress concentrates at the roots and torque is high enough (most of the cutting edges are in action by this time). For these reasons, it is better to focus on these parts of the tool (upper threads and shank). Of course tempering by this method is not the most effective but still it can help prevent the mentioned cracking as heat first touches the most vulnerable part of the tool: the outer shell (this is where the cracks start). The tip and the first few threads can be left "rock-hard" as it is unlikey for cracks to start here and having some extra Rockwells here really won't hurt at all. It's over a year by now and you may already know all of these but if not I hope it helps in the future.

[@AdventureswithaVerySmallLathe]

Thanks for the tips! Overall I think the tap felt a bit soft when I came to use it, but it's hard to tell exactly why. Most likely I over-tempered it, but it's possible the points got de-carburized because it took me so long to get to decent cherry-red temperature. I know that quenching isn't necessary as part of termpering, but I was taught during school shop classes that it was a useful way to make sure tempering is stopped, and the heat in the part doesn't spread any further. For future projects I'm going to try and rig up a tempering oven, so I can gently bring parts to the right temperature and hold them there for the right soak time.

[@bencebabar610]

It can have several reasons of course. Based on your Custom Die video, if you're using it to cut materials with high tensile strength like silver steel, the high cutting forces combined with the vanadium content of the material (which can already be in it in the form of vanadium-carbide that is extremely hard) it is possible that you lose those sharp edges pretty fast. Decarburization shouldn't bother you especially with the use of boric acid protective coating, the high carbon content of silver steel and the relatively short time you do the heat treating in (I guess it didn't take longer than 15 minutes). I'm also sceptic about tempering because you basically grounded off the tempered (discoloured) section of the tool. The most important thing you should really focus on is the right quenching temperature. Being a small part, this tool quickly loses temperature when you draw it from the heat and you should quench it as fast as you can. To be honest I don't see any red color when you quench this part although it's only a few frames. Try maintaining that cherry red color through the tool and be fast afterwards. In the Die making video you did way better. Keep up the good work!

[@AdventureswithaVerySmallLathe]

The BS1407 silver steel I used for both the tap and die doesn't contain any vanadium (unlike DIN 1.2210), and is very easy to work with compared to O1. The ground tapered part of the tap seemed to keep it's edge ok, but I saw some definite sign that the thread tips further down were deforming under the cutting forces. This was at the point on the tap where the cutting edge had only been ground on the flute side, and the other two faces were the original faces that had been exposed to heat treat. I think it's most likely that these peaks got too hot during the temper phase, as I really had very little temerature control, and I wasn't at all happy with how I did temper the tap. Thanks for the feedback on the quench. I have learned that the magentism check isn't a completely reliable to check for the austenite transition, and since making the video I now think it was a bad idea to check if the part was magnetic right before quenching, as it allowed the part to cool down. That said, I'm certain the part did harden. Thanks for taking the time to write constructive comments, full of useful information. Much appreciated, and I learn more as a result. Keep watching!

[@mamoshimamoshian9078]

Oh how awarding this is when you make it and works for you :) My choice of metal was not good that is why I have made tools again and again without being able to harden them!!! I just don't know how to choice the right one and specially it is hard when you buy them from a cheap place and you don't know what it is you are buying. But some how I am learning.

[@welderdude1]

Very good video. I enjoy your very descriptive narrations.

[@Throughthebulkhead]

Glad to see that you put my friend to work!

[@AdventureswithaVerySmallLathe]

Very useful they turned out to be, though they need a bit of training as a focus puller. ;)

[@Harrzack]

So great to see serious work being done on something other than a Hardinge or Bridgeport. So many of the available videos don’t seem to cater to the small machine users.

[@AdventureswithaVerySmallLathe]

Thanks! I'll keep making videos with small machines, as long as people keep watching them.

[@MLFranklin]

Fascinating project. Nice video!

[@Lemongrasspicker]

I am so glad to see you still making videos. Been hard to pay attention to youtube as of late. Nicely done with the tool sir. Thanks for the video.

[@AdventureswithaVerySmallLathe]

Thanks, good to see you back again! I hope life allows you more time for KZbin again in future.

[@EmmaRitson]

very cool, Alistair. be interesting to see the grinding procedures some day too! thanks for taking the time to enter!

[@AdventureswithaVerySmallLathe]

I hope I'll always be able to find time to enter. Your competition has become a pillar of this community, and I'd hate to miss it. I'll see what I can do about getting some decent grinding footage.

[@patrickdjebar9225]

No words to tell you how I’m impressed

[@edwardhugus2772]

First time viewer of your fantastic vids. I have subbed, and will now commence the binge watching to get caught up. Thank you for a great video ! Ed in Pennsylvania.

[@lourias]

Though I have no lathe at the moment, I appreciate your detailed process and experience.

[@jrkorman]

Very nice! I would certainly like to see a video on your "mini" jack! It looks quite useful. Really, the Lego guys must focus more on their work!

[@AdventureswithaVerySmallLathe]

Already working on it, thanks for watching!

[@robertoswalt319]

Very nice video. I am saving this so that I will be able to refer back to it when I need to make a special tap of my own.

[@AdventureswithaVerySmallLathe]

I'd strongly recommend watching This Old Tony's tap making video. It's a very different kind of tap, but the principles are the same, and he knows what he's doing way better than I do.

[@22iskander]

your so professional and yet so humble job well done 👏

[@asdwee4444]

When I first heard you I thought that you were This Old Tony Boy. The style is similar and the details are well explained. Thank you for this video!

[@AdventureswithaVerySmallLathe]

That's a huge compliment! I'm a big fan of This Old Tony, so this makes me think I must be doing something right. Thanks!

[@dannydetonator]

@@AdventureswithaVerySmallLathe All you're missing is a time machine or smthn of a kind. Sorry, i forgot, the no-nonsense english machining. Have been there, great (if boring) experience. (Boring is good).

[@AdventureswithaVerySmallLathe]

This Old Tony regularly uses his Lathe for time travel, but I can never seem to find the right section in Machinery's Handbook on how to set it up.

[@lensman5762]

Very good work. A few years ago I managed to machine a gear hob to cut the gears for a Webster IC engine using a similar method to yours. Tool had to be made to make another tool to cut the geometry on the silver steel and then a gear hob had to machined out of it . A lot of work but a lot of fun. Funny enough I cut the 1/2" hob on a miniature Sherline lathe.

[@AdventureswithaVerySmallLathe]

Toolmaking can be a really compelling hobby, and I've certainly been bitten. One of the first machining videos I watched was Myfordboy making a hob from silver steel, to free-hob a worm gear. I was almost immediately hooked!

[@lensman5762]

@@AdventureswithaVerySmallLathe Yes I agree. Right now I am busy cutting MT0 and MT1 taper arbors for the Sherline. I have made a couple of MT1 slitting saw arbors, an MT0 extended dead center and an MT0 extended live center to be able to get the tool in with very small diameter work. I am almost reluctant to take the top slide off now, that the angle is set correctly.

[@gyrogearloose1345]

Nice work! I like your approach, thanks for sharing.

[@TabletopMachineShop]

Hey I just found your channel! Awesome video, keep up the great work!

[@markdearman8236]

What you failed to do is grind your own tools!!! Never had the luxury of insert tools when I was an apprentice!!!!!Nice channel!!

[@Fabi3250]

I love youtuber, who dont forgett to link their vids! Gj anyways 👍🏻

[@curtisroberts9137]

Nice work. Good video. Produced a very professional looking item.

[@guitfidle]

Nice video, thanks for sharing!! I have actually run in to a couple situations where it would be nice to make a custom tap... I may have to try this

[@AdventureswithaVerySmallLathe]

It's a rewarding project. I suggest watching videos from John Creasey and This Old Tony to get different perspectives on how it's done. Both are excellent.

[@guitfidle]

@@AdventureswithaVerySmallLathe Thanks!

[@johntenhave1]

Great work. That was something of a leap into the unknown with great results. I shall look at my taps and dies with considerably greater respect thanks to your video. Many thanks.

[@nathanek6598]

Great video. Excellent quality videography and narration. Keep up the great work!

[@AdventureswithaVerySmallLathe]

Thanks, I'll do my best.

[@TheJoyofPrecision]

Well done, Alistair! Certainly looks better than the only tap I've tried making so far 🙂

[@AdventureswithaVerySmallLathe]

Thanks Max! Robin Renzetti's trick of polishing it with a cratex stick can work wonders on any tool or part. ;)

[@danedewaard8215]

Wow, what a great adventure!!! Very nice video!

[@Vladviking]

Great demonstration on things possible on a small lathe.

[@AdventureswithaVerySmallLathe]

Testing the limits of what a small lathe can do turns out to be great fun to make videos about, so I'm really glad people enjoy watching them too. Thanks!

[@BrisketChef]

LEGO space man as camera assist. You got my sub. Great vid.

[@notyou6950]

Those tolerances are better than those I deal with on large jet engines! It's impressive to be able to hold such tolerance.

[@unclebob540i3]

Nice piece of work. Very impressive.

[@filibertobarrera3839]

This is a great video to make threads original,guess helicoil,or insert was out of the question for this job.

[@AdventureswithaVerySmallLathe]

Yeah, the nuts have very little spare material, so I don't think there would be room for an insert.

[@firesurfer]

Designing and making taps is more art than science.

[@ELECTRICMOTOCROSSMACHINE]

WOW, SO GOOD. THANKS!!

[@scroungasworkshop4663]

OMG you sound so much like Jeremy Wade from River Monsters. Nice work and very interesting to watch. Thanks for sharing. Cheers Stuart 🇦🇺

[@Okie-Tom]

Very good and thorough. Thank you. Tom

[@250-25x]

very cool project. Since learning from Joe Pie....I now single point tap EVERYTHING from the chuck away towards the tailstock, upside down tool...and no CRASH! cheers G>

[@AdventureswithaVerySmallLathe]

I wish I could do that too, but the tool post just doesn't have enough room to hold the single point tool upside down. I only get to do r/h threads away from the chuck if I don't need the tail stock.

[@LeDibeau]

Making a tap is - high level skill!

[@donalfinn4205]

Great video. I wish I had your knowledge!

[@Ron_EZ]

Adventures with a Very Small Lathe - LOL Your videos appear to be "rabbit holes" that contain more rabbit holes that lead to still more rabbit holes... on and on it goes! I originally started to watch the "Making a custom die" video - to which you started off saying that to make the die you had to "make a custom tap" OK I'll watch that one first! Next, in the "Making a Custom Tap" you spoke of making a custom Gear that your lathe needed - OK another to watch...; a second time in the Tap video you spoke of needing a custom screw jack, and so it continues! LOL Great content!! I'm still trying to find that DAMN rabbit in the next hole!!

[@kevinmartin7760]

Indeed, a plain tapered end yields a slight negative relief to the cutting edges. An approximate formula for this relief is arctan(pitch×tan(taper)/(pi×diameter)) which in this case gives about 0.24 degrees. The formula is approximate primarily because the diameter varies along the length of the taper. I would be interested to see what you did to produce positive relief.

[@AdventureswithaVerySmallLathe]

That negative relief would certainly explain why my first attempt had no chance of cutting a thread at all. I haven't checked your math, but on a quick diagram I can see why that negative relief happens. A quick explanation of the grind I eventually did: I gound a flat relief just behind the cutting edge by carefully setting the angle of the grinding collet, then very gradually advancing toward the wheel, and checking carefully between each pass. It's not pretty, but it does work.

[@bobjimenez4464]

nice job........a little polishing to create the cutting tool relief does the job. creating the primary relief on a tap thread requires a cam driven thread grinder "Hybco" is one brand for prototype shops.

[@manojdhali5987]

Very nice creation & excellent machinery.

[@DIY3DTECHcom]

Impressive! I also did not know that when steel comes up to hardening temp it becomes non-magnetic!

[@swanvalleymachineshop]

Well done , hand held thread chasers will sort the crest / root radius on 55 deg threads . Cheers .

[@wayneacaron8744]

poppy;s workshop says WELCOME TO THE GAMES! nice work. poppy

[@rockmanharbinger3622]

The Skills You have develooed are certainly beautiful and valuable to the human species..I hope you survive the war..and are able to pass on these skills to another generation..you definitely..ROCKMAN😎

[@Timoffejj___RU]

😀 Настоящая заводская вещь! 👍👍👍 Хоть и сделанная дома 👏👏👏

[@blahblahblahblah2933]

When I watch, I like to pretend the lathe is the usual size and you are a giant.

[@bencesarosi7718]

lmao

[@samuelchadwick5993]

right that person needs to read his comment 😂

[@samuelchadwick5993]

@@bencesarosi7718 😍

[@Bodragon]

(2:38) - First time I've seen someone blowing down a straw to blow dust and scrap out of the way. Way to go man ! It always made me laugh whenever I saw anyone using *_air-in-a-can_* to do this. I have used the pipe part of a turkey-baster for donkeys' years now. Because of the wider diameter of most of the pipe, you can really blow up a good pressure with just your lungs. Much more effective than using a straw. You should try it. >

[@shadowdog500]

The tap came out great!!!

[@AdventureswithaVerySmallLathe]

Thanks! I made quite a bit of use of the camera gear you donated to last years prize while making this video, so thanks for that too! :)

[@somebodysdog]

Hi. First time video watcher, 3th. year machinist student. You know, that there is a internet full of a measurement charts, that can tell you the exact min. and max. diameters of the bore when making a thread and also there is a universal calculations, that atleast makes sense when you'r making bolt threads in millimeters. It's simple... Let's say, that you wanna make a ISO M8 normal female thread. Max.D for the hole is 7.972mm so lets call it 7.9mm and the Min is 7.76 so lets call it 7.75mm. Picth is 1.25mm. Now you always go for the middle of the toleranse scale, so just go with the 8mm drill and then go with the thread tap. Don't forget the lubrication and go slow. Remember to rewind if your using a lathe. Now how you use this info to do a male thread (bolt) is that you take the diameter of the hole you want and take of (-minus) the pitch and then round it of. now it's good to round it of to little under because the ridges might get sharp and start to break. Also if the male bolt threads are slightly under (like a 2-5 tens of a mm) it's fine. In normal use there should be some slight wiggle. There is also a plenty of charts in... (what ever obsolete system you 'muricans use) in the internet for you.

[@tylerjones6043]

Congrats you've made cutting threads sound like you have to be a genius to do so lol.

[@aion2177]

i leaned so much!! Thanks :)

[@askquestionstrythings]

I'll have to consider doing this to make a 3/4" 2TPI-LH ACME tap for a restoration of an old Artisan Lathe leadscrew nut.

[@mytuberforyou]

2:20 " And the whole chain is connected to the spindle by this belt" - it's actually the PULLEY on the belt that's most useful to make because it's much easier to make a pulley than a gear, you can adjust it in infinite increments by resizing, and recut it for (lower) ratios, all things you can't do easily with a gear.

[@316tomiller]

Not quite infinite increments. It is a toothed belt, so can only be changed in units of one tooth pitch on the belt.

[@Larry1942Will]

Very nice video. I've never tried to make a tap. Might have to try. I have a similar tool grinder that I struggle with. It needs some work to get it to work better. Subbed

[@BuildSomthingCool]

Nice build, great job on the editing

[@AdventureswithaVerySmallLathe]

Thanks Dale, that means a lot to me! :)

[@Hendreh1]

@@AdventureswithaVerySmallLathe Hello nice entertaining Video. For your next taps you can plan to grind some Back reliaf in the taper. To See what i mean . Inspect a purchased tap closly.

[@AdventureswithaVerySmallLathe]

@@Hendreh1 Yep, you're right. While I did add some back relief to this one, the video recording didn't work well, so I didn't show it in this video. I only realised afterwards that I should have ground in the back relief and the taper at the same time, in the same grinding operation.

[@Hendreh1]

@@AdventureswithaVerySmallLathe OK nice to know . I Just thougth , it would work in brass anyway. A wile ago i made a tap for a S20x2 internal thread . I can say Homemade taps with back relief work even in mild steel. One more questionen. Where do you buy your chemical paste that you smeer on the workpice before hardening? Greetings

[@AdventureswithaVerySmallLathe]

@@Hendreh1 The paste is Boric Acid mixed with methylated spirits (de-natured alcohol). Boric Acid is sold for a number of reasons, and is most easily available as an insecticide. I bought it from Ebay.

[@coquimonster31]

This is amazing.

[@tobyw9573]

Making your own taps could become more economical of time if you were making a 3-tap set of the same size ( starting, standard, and bottom taps of plus and minus fits). Could you get some reamers in there too with similar settings? Might make a nice presentation set.

[@westweld]

Craig introduced me to your channel through discord server and I've been going through and watching your videos.....really great content nice work

[@2lefThumbs]

It looks like it may be a model engineers 5/32" (3.97mm)thread (40 tpi, giving a pitch of .635mm), which uses whitworth 55°thread form. A quick search throws up plenty of RH taps, but no LH ones, so definitely worth the DIY. Maybe the nut bound on full insertion on the test piece because of the slight mismatch between 0.6 and 0.635 mm ? Or it may be a random 5/32-42, which would be closer to .6mm pitch of course

[@jaygoodwin6287]

loved this video so much!! Question not relating to the Tap itself but the oiling of the products before milling. How do you know when or when not to apply oil (lubricant) to the material you are milling. I watch a lot of these videos, well a reasonable amount here and there. I say to myself "that needs some lube, surely". Ive never done this kind of work so i'm curious. as a motor mechanic, i lube anything i'm trilling metal wise

[@umahunter]

Very nicely done man 👍👍👍

[@ProfSimonHolland]

that was so useful thank you

[@carneeki]

Great work Alastair! :D

[@AdventureswithaVerySmallLathe]

Thanks Adam, and thanks for being a long time supporter! :D

[@davestambaugh7282]

A thread grinder is a hybred machine. It is like an OD grinder with a lead screw and half nut just like a lathe but with a grinding head instead of a tool post. The wheel is dressed with the apropriate angle for the thread being ground. They come in both manually operated ones for small quantities up ones that are for high speed automatic models for mass production.

[@paco6641]

You are welcome! Greetings from Holland👍

[@Krmpfpks]

What a beautiful build. I hope you never break it, I would be scared to use it.

[@ProfSimonHolland]

Thank you...your project confirms I am way too impatient and stupid to make anything useful on a lathe.

[@felgate11]

You can get "FULL FORM" threading inserts, the insert has a shoulder ground either side of the tip so for instance for a 1/2" BSF thread, turn the o/d to .500" dead, then keep screw cutting until the shoulders "TOP" the thread till it's a few (5 0r 6) thou' undersize - No need for a gauge or wires, It'll fit the tapped hole everytime (in theory)

[@Rustinox]

Very nice video. Good luck with the competition.

[@AdventureswithaVerySmallLathe]

Thanks Rustinox! I really appreciated your recent video about file safety on the lathe. Essential watching for every machinist.

[@nikond90ful1]

Thanks for the video.

[@brendazamora1113]

loved the legos on the camera! :)

[@softsmoken]

i was curious how youd hold the end of the too thin to mill part, what a great little device