Cycle thread taps & dies

My main activity is restoring vintage motorcycles so having some clean up taps and dies is very useful. I have to prioritise on spending to afford some of the things I can’t make as it it is not a cheap hobby, the answer for me was to make them.
So far I have 5/16 and 3/8 BSCY in 26 TPI made of oil hardening tool steel and they have even been used to make new items sometimes in stainless as the thread depth is only .0205. the dies are made with the taps, anything larger can be screwcut, and I have chasers for that.
I know some will view this thread system as archaic but the motorcycle I am working on is 97 years old and apart from an engine has more in common with a bicycle (you can’t change history).
Having said that some of these threads were still in use into the sixties until UNF became more common and then of course Metric.
The main reason for posting is to show it is fairly easy to make them especially if you encounter an oddball size.
Attachment 19825

"The main reason for posting is to show it is fairly easy to make them especially if you encounter an oddball size."
Very interesting and thank you for sharing the info. If you do have a minute I would be very interested in how you go about making them.

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Originally Posted by thirdbike

"The main reason for posting is to show it is fairly easy to make them especially if you encounter an oddball size."
Very interesting and thank you for sharing the info. If you do have a minute I would be very interested in how you go about making them.

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not just odd ball sizes but custom bolts and nuts. I have always thought South Bend did a crappy job of tail stock hold down bolt. If they would have decreased the pitch the nut would tighten faster and like wise loosen faster.

Olderdan,
Did you make RH and LH? My oldest motorcycle was a 1926? Royal Enfield that was the first motorcycle to have foot gear-change, it still had the hand-change as well. Hand oil pump, spark advance/retard and externally adjustable main jet on a thing called a carburetor. I really, really regret selling it now to buy a new 1980 Yamaha TT500.
A lot of motorcycles from around the world were still using RH and LH threads into the early 1960's, not so dumb either as the total harmonics were considered and everything tightened itself up and as long as you knew never a problem.
The above 'bike I bought age 15 and rebuilt including a Gold plated carb as Dad had a polishing business,(it was Brass).
I wonder how a millennium would cope?

I've had several bikes over the years some were lots of fun more were lots of work all were unique in in their own right one way or another. a Powell that was supposed to be a mini bike but had a 10 hp Kohler a stupid and I mean that in the literal sense Honda 50 with a real tube frame not the stamped pressed factory thing. BSA 1 lung 500
ankle buster. Harley 45, chopped & raked 750 Kawasaki half a dozen 350 & 450 Honda's a 48 Harley Pan head a 74 Electraglide Triumph 650 a 1921 Ner-a-car but the 1 bike that if I still had it today that would melt a millennial's brain was my 73 850 commando that would pull the front wheel of the ground in 3rd gear if you sat back on the seat and really gassed on it would eat a Kawa 1300 or a GS 1100 Suzuki as long as you weren't going more than a 1/4 mile at a time. it would hit top about half way between the 1/8 & the 1/4 mark all you had to do was aly down on the tank and hold on .and let those 32 mm Mukuni s feed it the stock Amal 28's were better run around carb's but just couldn't feed it as well as the Mukuni's when you wanted to get there NOW! the only thing was when you wanted to start it you had better want to start it or it would toss you over the bars.

Well I take it the Commando wasn't an Interstate then? No way you would lift the front with a full tank of gas aye? I have some very funny stories to tell about adventures with Norton's. That Isolastic suspension was a revelation at the time but I would have laid money that a 750 was quicker over a short run. I had in order all of the 'H' series Kawaka's and if they could have connected the two wheels together with something other than rubber bands they would have been great bikes, the one that held the steering head on was a real problem plus they were crap on gravel. I remember what an impact Mikuni's had, A lot to do with the fact that they were new and if going from a clapped out single carb on a duel manifold to individual carbs was like supercharging.
I don't know if you can tell but I do like Norton's. Sacrilegious heresy to think that I consider the 1979 Triumph Bonneville probably the most beautiful motorcycle ever built, just a crying shame it couldn't go around corners properly.
Still to this day I always look at threads to check their hand regardless of what it is I am doing. Learnt young and looking first is good, just wish I could follow my own advice.

Forgot to ask, the Ner-a-car, by Osbourn Engineering Company?? Center-hub steering? A concept that just has to be fully embraced one day. Might have the builder confused. Can see the pictures in my head. I know that O.E.C. patented his Parallelogram steering concept and I built a trike with it. Solved a lot of the weight transfer problems with two wheels at the back not at the front where they should be.

The ner-a-car had the center hub steering designed by Carl Neracher made in both England and Syracuse NY. mine had an asthmatic 121 cc Sheffield engine the the 350cc Blackburne 4 cycle was popular in England transmission if you could call it that was a friction disk drive 3 settings 1 disk slid across the other 1 having a leather tire someone even put a 4 cylinder in one
Like I said about pulling the front wheel on the commando you had to sit all the way back to get it to do it plenty of power just too much weight up front. the nice thing about the engine mounting was the vibrations were not transmitted to the bars but really weak when an extra disk was added to the clutch I felt the transmission was undersized as I separated the internals and split the case on 2 of them and broke the primary a few times before I figured out I had too much clutch with the 5 pack Barnett

Hi ncollar
I agree with your comment on South Bend tailstock clamping, a bit of a blind spot on what is otherwise an excellent lathe.
With only a 2 inch travel on the tailstock barrel it is a real pain to have to clamp and realise when drilling deep holes. Before converting to a lever clamp I had tried different thread types on the bolt with no improvement. You may want to look at my post on the conversion which has transformed its use.

http://www.homemadetools.net/forum/l...1762#post94654

Quote:

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Originally Posted by thirdbike

"The main reason for posting is to show it is fairly easy to make them especially if you encounter an oddball size."
Very interesting and thank you for sharing the info. If you do have a minute I would be very interested in how you go about making them.

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I can't help much on making these as they were made some years ago before joining HMT, but there are some video's on Youtube on making taps etc.

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Thanks olderdan! We've added your BSCY Taps and Dies to our Fastening category,
as well as to your builder page: olderdan's Homemade Tools. Your receipt:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="http://www.homemadetools.net/homemade-bscy-taps-and-dies"> <img src="/uploads/204907/homemade-bscy-taps-and-dies.jpeg"/> </a> </div> </div> <div class="head pngfix"></div> <div class="left pngfix"></div> <div class="right pngfix"></div> <div class="blockover b1 pngfix"> <div class="title"> <a href="http://www.homemadetools.net/homemade-bscy-taps-and-dies">BSCY Taps and Dies</a> <span> by <a href="http://www.homemadetools.net/builder/olderdan">olderdan</a></span> </div> <div class="tags">tags: <a href='http://www.homemadetools.net/tag/tapping'>tapping</a>, <a href='http://www.homemadetools.net/tag/die'>die</a> </div> </div> </div> </div>
<!-- END /var/www/html/homemadetools/protected/modules/zeus/views/tool/postUpdate.php -->

Thanks guys for all your motorcycling memories, you have all had more machines than me it would seem. My best bike was a pre unit 650 Triumph Trophy much modified with a BSA Goldstar front end. Bob Joyner cams, SW valve springs, 10.5:1 pistons etc. also running twin Wal Philips so called fuel injectors. After much playing with gearing it would just hit the ton in third and about 115 in top, I used it a bit in amateur sprinting, best time ¼ mile standing start was just under 15 sec.
This was also my road bike and to be honest I have no right to be here but it was the best fun ever. I sold it after putting in the third crankshaft, over revving by not having a rev counter (and oh yes getting married).

Ya, that getting married changed a lot of things. I am wondering if it was worth it. My 72 Yamaha 650 twin was one of the things that was left behind.

Just had a few beers with a friend I met on my first day at school who had moved to South Island, He and his partner have come North to look after his mum so good to catch up. A 1928 Triumph 247cc motorcycle has emerged from a shed and now there is a need to cut some change gears to cut the correct threads needed for items such as a front axle, foot pedal mounts etc.
Why did I feel the need to go metrickery? If I had an Imperial lathe none of the threads I deal with regularly would be a problem.
Olderdan, I have an inkling that I may be exploring making taps any tips?

We know that some metric threads can be cut with inch leadscrew but from my searching it would seem that the reverse is not that straight forward, especially
26 TPI. Maybe some of the more mathematically minded on HMT might help (I can think of a few).
To be honest I would probably buy them at the prices these days, they seem a lot cheaper than when I made mine.
In the UK I buy from Tracy Tools and they ship world wide.
Attachment 19861
By the way will the bike look something like this.
Attachment 19862
Good luck with it.

The magic ratio relating metric and inferial is 1.27. (The prime factors of 254 are 2 and 127). While a 127 tooth gear is doable, it's generally very unwieldy for the averge banjo. Approximations are in order.

Using my GEARFIND program, the simplest two gear approximation is:

47:37 = 1.27027... with an error on the order of 0.02%

If willing to go to a four gear set...

30:23 - 37:38 = 1.27002... with an error on the order of 0.002%

Using gears with larger numbers of teeth can produce better approximations but I've searched for small tooth count sets to keep them of reasonable diameter. You're free to download the program and explore it more fully if desired.

Tracy Tools is definitely GOOD.....

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Originally Posted by mklotz

The magic ratio relating metric and inferial is 1.27. (The prime factors of 254 are 2 and 127). While a 127 tooth gear is doable, it's generally very unwieldy

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I have known many lathes with 127 teeth gears fitted, in fact my current 12x40 Jet has one.

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Originally Posted by olderdan

Thanks guys for all your motorcycling memories, you have all had more machines than me it would seem. My best bike was a pre unit 650 Triumph Trophy much modified with a BSA Goldstar front end. Bob Joyner cams, SW valve springs, 10.5:1 pistons etc. also running twin Wal Philips so called fuel injectors.

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The Wal Phiips devices were a pain to tune because the fuel/air ratio was adjusted on the fuel valve as was the throttle stop, which meant that after each adjustment of that you had to go and adjust the air valve opening and then the throttle stop.
I reversed the controls. That is; the throttle stop and cable were put on the air valve as was the ratio adjustment. So instead of 3 adjustments each time there was only 1. It made them so much easier to set up. In Australian racing at that time we could use any fuel and I made some WP clones with larger fuel valve spindle to take the larger holes needed for alcohol.
Click on pix for full size versions.

Attachment 19870
Here is a pic of the WP "injector" for those unfamiliar with it.

Attachment 19871
On the left is the original crazy linkage, on the right is my simple but very effective modifications.

Attachment 19872
Pit work 1960s style, adjusting my WP clone.

Quote:

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Originally Posted by NortonDommi

Forgot to ask, the Ner-a-car, by Osbourn Engineering Company?? Center-hub steering? A concept that just has to be fully embraced one day. Might have the builder confused. Can see the pictures in my head. I know that O.E.C. patented his Parallelogram steering concept and I built a trike with it. Solved a lot of the weight transfer problems with two wheels at the back not at the front where they should be.

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The O.E.C used a 4 bar linkage system for the steering but it was not a parallelogram layout. It had no physically defined steering axis as do most steering system, the 4 bar linkage gave rise to a "virtual" steering axis. It was known in its day a a good steering machine, however the geometry had a fundamental flaw in that the tyre contact patch moved rearward as you moved the steering away from straight ahead, Most if not all other steering systems move the contact patch forward when steered. The OEC layout meant that the steering was unstable under braking. It is likely that they only got away with it due to the abysmal brakes of the period.

Attachment 19873 Click for full size picture.

This was my take on the hub centre steered theme from the early 1980s

Having followed up on Olderdan's hint to check the U tube videos, it would appear that the taps were made from bolts with the existing thread form. While I had always understood the basics of making a simple "thread chaser," the one video goes into detail making a real tap from an existing bolt. This is a bit more involved and requires a substantial equipment outlay. I guess I will be needing to buy the taps. Thank you for sharing all the same.

You are right about them being a pig to adjust, I wish I had thought of your brilliant mod about 50 years ago, never seen one on a 2 stroke before.
I got shot of them after a while as for a road bike if you forgot to turn of the fuel as you stopped you ended up with a sump full, I don't think they were ever intended for road work so I switched to twin Amals which seemed to work almost as good except on full bore.

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Originally Posted by olderdan

You are right about them being a pig to adjust, I wish I had thought of your brilliant mod about 50 years ago, never seen one on a 2 stroke before.
I got shot of them after a while as for a road bike if you forgot to turn of the fuel as you stopped you ended up with a sump full, I don't think they were ever intended for road work so I switched to twin Amals which seemed to work almost as good except on full bore.

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Actually they were advertised at the time for road use as well as Racing, although Wal was a speedway bloke so IIRC they were first made for speedway. That means using alcohol which needs much less accurate mixture control than petrol.
I used them and my clones for only a few years, always on race bikes only. I later used various carbs of my own design and later still discovered the Gardner carbs which were superior in all aspects. In the early 70s I moved to England to race in the island. I started a business making cast wheels and race chassis and Ron Gardner came to me for a chassis to resurrect the Rudge marque for which he and a partner owned the rights. He had stopped making the carbs then due to other work, we had become friends and I approached him with the idea that I restart the manufacture of the carbs, but with a slight difference. I was getting a lot of magnesium castings done and I talked him into letting me make them in Magnesium. Since then the interest in classic racing has boomed and those carbs are being made again by the Gardner family but in aluminium again. i still use Gardners on my race bikes unless the regulations forbid them, some organisations do. Then I use a Dellorto SS1.

Attachment 19881 Click for full size view.

Initial fitting of a WP "injector" on a 2 stroke which was the first engine that I ever built. I did the casting in the backyard.

Attachment 19882

Hello Olderdan,
Last time I saw it in one piece was around 1980 but from memory that looks very similar, Had the chrome trim on tank and rims but will be painted factory maroon. Needs one rim replaced which is not bad.
I have a reasonable selection of taps but will look at Tracy Tools if any needed. I also find https://www.voelkel-shop.com/en/ not bad either and am in love with their serial taps.

tonyfoale,
Thanks for the observations on the Wal Phillips carb I've never seen one but always been fascinated with their simplicity. There was a popular carb based on similar concept used in USA car circle racing I believe.
To you and Olderdan thanks for the correction as to O.E.C. steering. I did use this idea on a trike front end that was built backwards with one wheel in front as it was set up to move the contact patch to outside of triangle, seemed to work well and a huge improvement over the girder front end it replaced.

Quote:

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Originally Posted by NortonDommi

tonyfoale,
Thanks for the observations on the Wal Phillips carb I've never seen one but always been fascinated with their simplicity.

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it was simple in concept, that is an air valve connected to a fuel valve via an adjustable linkage. However, that simplicity hid some underlying complexity in matching those two valves which was beyond what the linkages could correct, unless the design was spot on for the engine under consideration.
The problem stems from the relationship between the flow area and angular opening of each valve. neither are linear due to the nature of air and fuel flow and geometric effects. As a quick example, imagine that the fuel valve is too large for the engine. A first thought would indicate that you only have to adjust the linkage to open the fuel valve less relative to the air valve. The problem with this is that then the fuel valve is operating in the range where the geometry dictates that the rate of area increase is high. In other words a small increase in the throttle valve opening will result in a disproportionately greater opening of the fuel valve compared to a carb with a smaller hole in the fuel valve. Therefore in order to be able to get good mixture ratio throughout the opening range you would have to size the fuel hole to each engine. Of course as this was sold as a general purpose device the hole sizing had to be a compromise.
On the other hand the Gardner was just as simple mechanically, but much more sophisticated in its mixture production.

Attachment 19891 Attachment 19892 Click for full size pix.

Attachment 19893 Attachment 19894

Pix of a Gardner.

LOL, as soon as I saw the header I knew it had to be Tony posting. Pretty sure the majority on here have never even heard of a Wal Phillips injector. Takes me back to the 'Pride and Clark ads in 1960's motorcycle magazines, my father was a subscriber, I couldn't wait to get hold of them day after delivery (dire consequences if I opened one before he had a chance to read it LOL)

Didn't Jaguar use a modified version of Gardener at one time? (6 bank with common slide?)

Quote:

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Originally Posted by tonyfoale

I have known many lathes with 127 teeth gears fitted, in fact my current 12x40 Jet has one.

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I was always told to use 127 t gear to cut metric threads on inch lathes (the only ones we had when I was training in 1970's)
For anyone who isn't 'keeping up' 25.4mm=1inch, first full multiple of 25.4 is 127. On a big lathe with a lot of torque it can be a big gear though, gear teet can only be made so small before they break up

Quote:

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Originally Posted by crazypj

LOL, as soon as I saw the header I knew it had to be you posting. Pretty sure the majority on here have never even heard of a Wal Phillips injector. Takes me back to the 'Pride and Clark ads in 1960's motorcycle magazines, my father was a subscriber, I couldn't wait to get hold of them day after delivery (dire consequences if I opened one before he had a chance to read it LOL)

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Unfortunately my father never subscribed to anything like that but I was lucky to have been given about 20 years worth of the Blue'un and the Green'un 1940s through 1950. I read each one religiously and so I formed a good historical background prior to the 1960s when I started riding.
My father did have a bike before I came along but just for transport not for fun. My mother made him get rid of it when he dumped her off the back into mud.

Attachment 19902 Click to enlarge.

Dad and his bike.

LOL, pretty sure there are still about 20 yrs worth of 'Blue and Green' buried in front garden when my mother made dad 'get rid' of them I remember him digging holes about 4 ft + deep and placing stacks in them.He had them from mid-early 50's until late 60's. Mother couldn't get him to drive so we only had motorcycle/sidecar growing up. I still think outfits are the most fun you can have with your clothes on. He never did get a car licence.
Oh, just remembered , this was about Cycle threads. I learned precision machining so I could fit BSA wheels into my Royal Enfield 'Continental's' (had 5 at one time, could only keep one running though ;o) ) It's come in handy over the years to be able to 'make' stuff fit'

Quote:

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Originally Posted by crazypj

LOL, pretty sure there are still about 20 yrs worth of 'Blue and Green' buried in front garden when my mother made dad 'get rid' of them I remember him digging holes about 4 ft + deep and placing stacks in them.He had them from mid-early 50's until late 60's. Mother couldn't get him to drive so we only had motorcycle/sidecar growing up. I still think outfits are the most fun you can have with your clothes on. He never did get a car licence.
Oh, just remembered , this was about Cycle threads. I learned precision machining so I could fit BSA wheels into my Royal Enfield 'Continental's' (had 5 at one time, could only keep one running though ;o) ) It's come in handy over the years to be able to 'make' stuff fit'

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Although I built two championship winning sidecars, my own attempts at riding asymmetric three wheelers always ended with Desperate Dan style holes in hedges. diabolical invention. Actually it was my inexperience with sidecars that allowed me the freedom of thought to design something a bit different which worked well. Today's racing rules have outlawed most of what I did. Here are a couple of pix.

Attachment 19903 Attachment 19904

Attachment 19905 Attachment 19906

Attachment 19907 Attachment 19908

Thanks Tony, don't think I've ever seen those pics before.. Not really surprising steering was banned, probably an unfair advantage to have 'F1' set up.
I've had a few hairy moments in the past, the Kawasaki engine didn't get much mpg but was fun below 100mph where you could often use torque to 'steer' rear end, Exits from roundabouts were 'interesting' on street outfits, (even lowered with 15" car wheels and heavy duty leading link front end)
BTW, that isn't where I got the 'crazypj' nickname

Really interesting Tony, I know Regs are supposed to create more of a level playing field but they must inevitably stifle development to some degree.
It is a pity there is not a totally free class to see where it could all go, I remember the fuss that the Owen Greenwood trike caused at the time but to be fair it didn't even have a sidecar.
I know you have published technical books but if you ever felt like writing one about your life experiences with motorcycles it would make a good read.
Regards
Olderdan

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Originally Posted by olderdan

I know you have published technical books but if you ever felt like writing one about your life experiences with motorcycles it would make a good read.
Olderdan

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I doubt that I will write a book on that topic but here is a video on the same theme. Skip to 13 mins 30 secs if you want to avoid the Spanish.
https://youtu.be/bVy8nMQBIZY?t=1