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I hate to tell ya this Rod ... but 15.88 mm is 5/8 inch not 3/8 inch. 3/8inch = 9.525mm :p

See! I told ya I don't like to use Imperial so 15.88mm it is. I always say 3/8 instead of 5/8!

Funny back when I drove a mini in the 70's I knew the size of every AF spanner and socket size at a glance. Now I am the same with metric but I have to do some maths which I got very wrong in this case but you know what I mean :fan:
 
I know what you mean Rod. I still can't pick the difference between a 12mm nut and a 13mm nut ... and true to Murphy's law I always grab the wrong sized spanner ... lol
 
I know what you mean Rod. I still can't pick the difference between a 12mm nut and a 13mm nut ... and true to Murphy's law I always grab the wrong sized spanner ... lol

I think I have this worked out. I think at a bolt shop there is a standard bolt head that goes with a given M thread size. Except the car manufacturers deviated from this and invariably use fine threads. So the car bolts go M6, M8, M12, M14. This equates to 10mm, 12mm, 17mm and 19mm heads. So in answer to your question, if it is M10 and it came off a car (which is a fine thread and usually with a flanged head), it will be M12. If it is a coarse thread or even a fine thread standard bolt (eg no flanged head) it will be M13.

in the smaller car bolts (M8, M6), they don't use fine threads so M8 is pretty much universally M8x1.25mm thread on or off the car.

At a bolt shop, they generally skip the M14 and go straight to M16 so anything M14 is usually a special order (which may mean a box quantity). I have found the fine threads are about three times the price so usually only buy them if they have to mate to a threaded vehicle component. The 70mm fine thread M12’s I buy cost more than the 200mm M12 coarse thread ones!

I think this is where our imperial cousins get confused with metric. As M bolts are not in general use, they don't understand general practice and customs that actually defines a pretty narrow range of bolts that are found in the wild!
 
I think I have this worked out. I think at a bolt shop there is a standard bolt head that goes with a given M thread size. Except the car manufacturers deviated from this and invariably use fine threads. So the car bolts go M6, M8, M12, M14. This equates to 10mm, 12mm, 17mm and 19mm heads. So in answer to your question, if it is M10 and it came off a car (which is a fine thread and usually with a flanged head), it will be M12. If it is a coarse thread or even a fine thread standard bolt (eg no flanged head) it will be M13.

in the smaller car bolts (M8, M6), they don't use fine threads so M8 is pretty much universally M8x1.25mm thread on or off the car.

At a bolt shop, they generally skip the M14 and go straight to M16 so anything M14 is usually a special order (which may mean a box quantity). I have found the fine threads are about three times the price so usually only buy them if they have to mate to a threaded vehicle component. The 70mm fine thread M12’s I buy cost more than the 200mm M12 coarse thread ones!

I think this is where our imperial cousins get confused with metric. As M bolts are not in general use, they don't understand general practice and customs that actually defines a pretty narrow range of bolts that are found in the wild!

imperial has some of the same issues with automotive hardware but not always... so it's just as confusing. it seems people usually have an afinity for one or the other. i like fractions so i have no issues with imperial not just because i'm american. but i see how people like working in decimal.
 
imperial has some of the same issues with automotive hardware but not always... so it's just as confusing. it seems people usually have an afinity for one or the other. i like fractions so i have no issues with imperial not just because i'm american. but i see how people like working in decimal.

Aah, the Metric System, what a mess. Or should I say, how any "changeover" will be a complete disaster. It can't help but be a mess. Not that any Govt official would admit it. While the Metric Conversion Board was in existence, it was supposedly ILLEGAL to import or sell any imperial tools or measuring equipment. I remember being forced to buy 150mm steel rule... As soon as the Board was disbanded it was back to business as usual!!

Although SI Units are the only legal system of measurement in Australia, after 40 years we buy 3/16" x 25mm screws (!) at the hardware store, car wheels are 17" x 8" but the tyres are 245mm x 17" and nobody knows what a hectare is, so big land is acres but suburban land is square metres, unless you are a surveyor (maybe).

Our toolboxes are twice as big now because we need two sets of everything! As a toolmaker, I have various taps and dies for Metric coarse and fine, BSF, Whitworth, BA, UNF, UNC, Brass 26tpi, and ME 32 & 40tpi !!!!!!!!! Not to mention all the hand tools. Whit, mm and AF. What a schemozzle. And COST. If everything is metric, it's the best system overall.

I could go on, but nobody is listening anyway... :)

Regards, RossG
radial1951
______________
 
Aah, the Metric System, what a mess. Or should I say, how any "changeover" will be a complete disaster. It can't help but be a mess. Not that any Govt official would admit it. While the Metric Conversion Board was in existence, it was supposedly ILLEGAL to import or sell any imperial tools or measuring equipment. I remember being forced to buy 150mm steel rule... As soon as the Board was disbanded it was back to business as usual!!

Although SI Units are the only legal system of measurement in Australia, after 40 years we buy 3/16" x 25mm screws (!) at the hardware store, car wheels are 17" x 8" but the tyres are 245mm x 17" and nobody knows what a hectare is, so big land is acres but suburban land is square metres, unless you are a surveyor (maybe).

Our toolboxes are twice as big now because we need two sets of everything! As a toolmaker, I have various taps and dies for Metric coarse and fine, BSF, Whitworth, BA, UNF, UNC, Brass 26tpi, and ME 32 & 40tpi !!!!!!!!! Not to mention all the hand tools. Whit, mm and AF. What a schemozzle. And COST. If everything is metric, it's the best system overall.

I could go on, but nobody is listening anyway... :)

Regards, RossG
radial1951
______________


I agree with a lot you say. It is 30 years since we only taught metric in high school and I think I was lucky because I started high school the year before. I do remember being relieved that we did not have to do sums in quarts, pints and gallons and the like any more!

For me, measurements of rainfall, property areas and temperature were the last to gel. Gowing up on a 40,000 Ha property like I did never sounds as impressive as saying 100,000 acres! But then I lived briefly in northern Queensland where properties were measured in square miles. This sounded really impressive but when a guy told me he had 100 square miles. I eventually did the maths in my head to find he only owned 64,000 acres (stuff the Ha!) which was a small holding by my experience!

However, having studied some engineering along the way, there is no doubt that the SI metric system is vastly easier to work with when calculating things like power, force and the like. However today, the software which did not exist in my time probably does it all for you. I think when we are just in the workshop choosing between feet and metres, we never get to appreciate this logical systematic approach underpinning the SI system.

I have long since personally adopted the metric system, I never buy a tape measure with inches and am a member on this forum simply because your EZ steam engine has a metric plan available!

This Wiki link about the Aussie Metrification process and the links at the top of the page to the US and UK experiences makes interesting reading.

http://en.wikipedia.org/wiki/Metrication_in_Australia

Interesting that only 3 countries in the world remain in the imperial world. Whether we like it or not regardless of where we live, we are all going to have to deal with both systems due to the rich legacy of Imperial units and the logical thought behind the SI system as a whole. I think it is only in the last 5 years or so that our houses are fastened with M12 bolts instead of 1/2". I always found this frustrating when I went bolt shopping to have to come home with imperial ones!
 
Well, got a little bit further today. I widened and deepened the undercut and parted off the tip to get the length right. The undercut is sitting at 9.5mm wide but there is plenty of room to go wider. I am pretty sure that is enough for me to withdraw the crossslide while powering down the lathe at the same time in this distance.

DSC_2475_zps58a215bb.jpg


I also went by Bohler Udderholm and collected a bit of steel on the way home from work. I had an interesting commute, but it ended up being not that far out of my way only adding 20 minutes to the trip.

DSC_2477_zps8ea0ca29.jpg


This is some 12mm and 25 mm round as well as a piece of 15.88mm hex in 1214 bright mild steel. In case you are wondering, that is 3/8" just to prove that imperial units are alive and well in a country that adopted metric 30 years or so ago). Bohler Udderholm being a German based company ( I think ) has no imperial measurements anywhere on their web site, so 15.88m it is!

The bad news is that I am told I can't weld this stuff ( might add that my welding skills are not much better than my thread cutting skills!).

The 12mm was only $12 a length but BU have a $50 minimum order and cash sales have to be arranged before 3:00pm but I was able to book it to a credit card over the phone and pick up after 4:00.

Anyway, these all came in 3.6m lengths and Trumpy and I have gone halves in it so we ended up with 1.8m (6') of each size for about $40 each. Now what he does not know is that when he comes over to pick it up later in the week, he has to give me a lesson in thread cutting! :eek:;)

I've got a meeting tomorrow evening so the next installment will be Wednesday. Hopefully, I will have time to get my change gears swapped over some time.

If anybody else in Brisbane wants some stock from BU and don't need metres of it, then I would be in for a shared buy like this and Trumpy may even join in too!

Hi Rod,

Bohler is good steel.Here is my Bohler story from 1965.

We used it for can stamping dies in Metal Box,Singapore. When I asked for the Bohler Steel Cat. No,I was told to go away.Just machine as per drawing. It is classsified.:wall::wall::wall:
I did ask to witness the heat treatment process and told.It is classified.:wall::wall::wall:
Bohler Steel Saleman happened to be my long lost Trade School class mate.
He gave me a Bohler Heat Treatment Manual.:D:D
Twenty years layer,did my own heat treatment.Taught my machinist everything.:D:D:D Thereafter he was the heat treatment expert for all our forming rolls and punches.
 
G'day Rod.

Back in Perth after a week in the never never.

Yeah that 1214 bright mild steel will give you trouble if you weld it, has a high lead content, also known as free machining mild steel.
Great to work with though.

There is few options for material from Bohler which I would recommend.

CS1020 bright mild
Bit sticky on the inserts and needs a high spindle speed to get a good finish, welds well and will not go hard.

K1045 carbon steel
Very similar to the above, machines well, nice finish, can weld but will harden if allowed to cool down quickly or quenched. Best to pre-heat before welding. (I would say the last batch of flat bar that was killing the countersink tools you have was most likely this stuff, very common material)

4140 high tensile
I love this stuff, is very tough, machines well beautiful finish will wear insets fairly quick, chip breaks nicely with the right feed, if you get swarf stringers on the lathe with it be aware they are razor sharp and will have no problem taking fingers off if caught up.
welds well although pre-heat is essential and submerged in kitty litter afterwords or it will go hard as a rock and crack.
Can be case hardened or through hardened with the right process. Also will work harden if the tool is allowed to rub instead of positively cut. (good example is drilling, go easy on the speed here)


You may already know these materials.

Here in OZ the 3 are the most common steels used in the machining industry. thats without going into the tool steel range such as EN25, EN36A range, All 3 come in round bar, hollow bar and flat bar.

Happy machining.
Baz. ;)
 
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Baz, Awesome information thanks.

Wish I could head out into the bush for a week about now :(
or any time actually!
 
No drama's Rod,

For a bloke that is fairly new to the game and self taught you are having a bloody good crack at it, was very impressed with the carriage stop you made,

have worked with tradesmen that would have trouble with designing and making that, also probably 25%+ or so tradesmen don't know how to cut a thread on a lathe, I finished my time 15 years ago, (not long ago really) these days tafe and employers rush young blokes through to satisfy the skills shortage, The Art of manual machining I feel is slowly fading away.

I left the trade for that reason.


Yeah I love the mine site life, I work for Atlas Copco as product support on their blast hole drill rigs, I do field service so I am always moving around to different places. The scenery is amazing but as you know too well the countryside is hot dry and harsh. 12hrs in the sun every day gets a bit beyond the joke though. The missus reckons I am like a reptile, if the temp falls below 30 degrees I go into hibernation and seem to thrive when it is around 38-40 deg c

It just tipped 42 deg c at my place for the third day in a row, so there is no getting away from the heat at the moment.



Here is a great book from H+F that I well recommend, I think just about every apprentice fitter/machinist for the past 20 years or so lived by it. A lot of the methods are old school but they have been proven over and over again.
It is on the tech school book list Australia wide.

http://www.machineryhouse.com.au/L341


Has most things you need to know about the trade in it.

Heat treatment
thread cutting
gear cutting
mathematical formula
all sorts of stuff, 632 pages of it actually.

Baz,
 
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Well, Trumpy came over to pick up his share of the material we bought this afternoon and it was nice to meet another forum member.

I had set up the change gears to start my threading practice and had some problems as the initial pass was far too fine (about 0.7 instead of 1.75). After quite a few hours, and checking all the gear ratios about 3 times, I finally worked it out. I had the half nut lever in the wrong position! I have never really understood how this lever works as my last lathe did not have one. It has been further complicated that the thread chasing dial did not work in the threading position but worked in the other position so I think I will ask Hare and Forbes to sort that out for me under warranty.

I know when the half nut lever is up, you can engage the cross feed and also longitudinal feed and I knew the longitudinal feed also worked with the half nut lever down, but I did not realise that the longitudinal feed rates were different!

After I got this sorted, I found it very easy to cut a thread and the lathe only runs on about 1 turn or less when switched off, so I know that I can use much shorter undercuts, probably 3-5mm. Once I was done, a nut went on quite nicely and I ran a die over it as suggested and it did not make much difference so I was happy with my first thread!

Too late tonight to put any pics up, I think I could confidently move straight to the drawbar now but will have another couple of goes just to be sure.
 
Hi Rod,

Looking very smart now.

QCTP and other stuff,

I recommend this place http://www.cdcotools.com/

I have used them heaps and they are the cheapest around. Also service is good.

The only thing is the shipping, to make it worthwhile it is best to go with a USPS flat rate box for around $50 and fill it.
Has a weight limit of 20lb.

Baz.

Thanks Baz also good for measuring tools as well at good prices. Watch out credit card here I come.

Rossco
 
Rod it's a pity you only do Toyota stuff. Looking for sliders to suit my GU IV Patrol.

Here is a good vids on threading and lathe set up.
[ame]http://www.youtube.com/watch?v=zoBsCrSYUhE[/ame]
[ame]http://www.youtube.com/watch?v=I0h6DMksURo[/ame]
[ame]http://www.youtube.com/watch?v=2YxeSbArIQQ[/ame]
[ame]http://www.youtube.com/watch?v=EWWB68ozvBE[/ame]

and one more for 60 degree pitch.
http://www.youtube.com/watch?NR=1&v=8aIiEP8yEcE&feature=fvwp
 
Rod, before you hassle H&F make sure the threading dial is engaged on the lead screw properly. You may have to loosen it's mounting bolt and reposition it so that the gear of the dial fully engages the lead screw threads. Don't expect it to spin quickly either. With the lathe set at 60 rpm or so the dial will take minutes to revolve 1 turn. You'll have to watch very closely to see it move ... lol

Thanks again for the shop tour. I'm still amazed at how much stuff you have in that tiny shed and yet how much working space you have. A job well done! (It put's my shop to shame ... lol )
 
I know when the half nut lever is up, you can engage the cross feed and also longitudinal feed and I knew the longitudinal feed also worked with the half nut lever down, but I did not realise that the longitudinal feed rates were different!

After I got this sorted, I found it very easy to cut a thread and the lathe only runs on about 1 turn or less when switched off, so I know that I can use much shorter undercuts, probably 3-5mm. Once I was done, a nut went on quite nicely and I ran a die over it as suggested and it did not make much difference so I was happy with my first thread!

Well done, Rod. I sometimes use a die to FINISH a thread to size and correct form after roughing it out by screw cutting (leaving it a bit oversize). Highly stressed threads need the correct root radius and good finish. Made special length wheel studs for race cars that way.

Make sure your lathe's half nut lever and the power feed levers are INTERLOCKED properly so that they cannot be engaged simultaneously. Big trouble if that happens, somethings gotta give... Maybe something needs adjusting inside the apron.

Regards, RossG.
radial1951
______________
 
Well done, Rod. I sometimes use a die to FINISH a thread to size and correct form after roughing it out by screw cutting (leaving it a bit oversize). Highly stressed threads need the correct root radius and good finish. Made special length wheel studs for race cars that way.


Thanks Rossco, I am over threading for this week I think!

DSC_2479_zps7566ca12.jpg


DSC_2482_zpsae5f6670.jpg


It all (eventually) worked like a charm with all of the help and advice on this thread. Thanks everyone.
 
Thanks Rod for Buds customs web I will be making a few phone calls very soon.
 
Thanks Rossco, I am over threading for this week I think!

DSC_2479_zps7566ca12.jpg


DSC_2482_zpsae5f6670.jpg


It all (eventually) worked like a charm with all of the help and advice on this thread. Thanks everyone.

Well done Rod. That's a nice looking thread!
 
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