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Oh heck I've been sectioned

trapper

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Here is a pic of atrio of front nib/grip sections I've turned up on my metal lathe. These are from the Tutorial I'm writing up on the subject. These are all turned in 6082 aluminium and then mirror polished at 1000rpm on the lathe with rag wheels and polish sticks;
full story and how to soon when I've finished the subject pens to put them in context.They are all set up for cross style mechanisms

If anyone is thinking of getting into "kitless pens" I do advice trying something like this first. It is alot cheaper and tooling requirements are not great.......... my triple start thread tap and dies cost well over £180.00 in all.
 

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ataylor

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The picture doesn't do them any good trapper, but i can see what is involved in what you are doing and i take my hat off to you. :thumbs: Keep up the good work i am sure this will come fruition. :bwink:
 

clumsysod

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My first question is: Why a triple start thread?
Would a single not work equally adequate and for our purposes be better because it would stop in the same place every park not having to worry about grain match.
I suppose there is a good reason but I am buggered if I can think of it.
 

creaky

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Really interesting, looking forward to seeing finished pieces and tutorial. Great stuff.:thumbs:
 

Jimjam66

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My first question is: Why a triple start thread?
Would a single not work equally adequate and for our purposes be better because it would stop in the same place every park not having to worry about grain match.
I suppose there is a good reason but I am buggered if I can think of it.

George, I don't own one but I can tell you what the argument is: Particularly when screwing the cap onto a fountain pen a multi-start thread will reduce the amount of screwing needed to seat the cap. A triple-start thread, for instance, will require only one-third of the turns an equivalent single-start would need. Most kit FPs have quadruple-start threads cap-to-barrel.

As you rightly point out, the consequence of using multi-start is that you need to choose exactly the right start each time to line up any grain or other features on cap and barrel, and do it each time you use it.

You pays your money and you takes your choice ... :thinks:
 

trapper

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Okies well
A standard thread would need to be longer in reach to adequtely secure say cap to the main body of a pen....... think why a cap with a clip might open itself when inside say a jacket pocket hanging off the clip......... the triple start gives you three chances to hold it together and not ruin a your Armani. in a shorter distance.... its more pleasant in appearance thats all
 

clumsysod

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Thank you for opening this thread, I am finding this most intriguing!
I don't want to detract from above but my next question:
These are all turned in 6082 aluminium
I assume that is the grade of metal maybe even a superior grade yes/no?
I think I would like to try something along these lines. I have turned some ally at the factory by hand before I got the sack.
Its awkward on a wood lathe but not impossible at all. I would have to use standard taps and dies as that is all I have access to.
My thinking is to tighten up to a O-ring thus reducing the number of turns and adding some grip to retain it.
Has this been tried tested and proven and I am wasting my time?
 

trapper

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Aluminium Like many alloys is available in many grades. Some are good for machining some not so good others dont even think of anything other than cutting bendinf and formiing with press brakes and the likes 6082 seems to turn and drill smoothly with not too haevy wear on the cutting tools.......... can even be turned with your chisels on your wood lathe but do wear gloves if you try this the swarf can be quite hot and sharp
 

Jimjam66

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I would have to use standard taps and dies as that is all I have access to.
My thinking is to tighten up to a O-ring thus reducing the number of turns and adding some grip to retain it.
Has this been tried tested and proven and I am wasting my time?

No, George, you wouldn't be wasting your time. Couple of things to consider, though. M12 seems to be about the smallest you can use for cap/barrel threading (some use M14). The standard M12 threading is (if memory serves) 12x1.25, the second number being the distance between sequential 'peaks' of the thread. It is also the height, or distance from a 'peak' to a 'valley' of the thread. So an M12 thread would leave 9.5mm of core material, being 12mm less 2 by 1.25mm. Not bad until you consider that the section will be threaded into the barrel at this same point. (Barrel has a male thread for the cap, a female thread for the section.). Assuming you use a standard M6 tap for the section, you're losing (6mm plus 2x1mm) 8mm from your core. So you're left with a barrel wall thickness of (1.5mm divided by 2) 0.75mm. Not much!

Most kitless folk therefore opt to use an extra fine (but still single-start) M12 die, M12 x0.75. They're not too expensive (like here) and they allow better strength because you lose less core material. As an added benefit the threads look less 'industrial.
 

Jimjam66

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Sorry, bad math there! Don't try figuring things out while chasing a toddler with an open bottle of talcum powder! :shocking::shocking:

The section thread is usually an M8, and the threads don't have any effect on the calcs because they go the other way (am I talking sense?) so the result is the same.

Perhaps I should put the iPad down for a while and vacuum up talc powder instead ... :goesred:
 

Terry

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No, George, you wouldn't be wasting your time. Couple of things to consider, though. M12 seems to be about the smallest you can use for cap/barrel threading (some use M14). The standard M12 threading is (if memory serves) 12x1.25, the second number being the distance between sequential 'peaks' of the thread. It is also the height, or distance from a 'peak' to a 'valley' of the thread. So an M12 thread would leave 9.5mm of core material, being 12mm less 2 by 1.25mm. Not bad until you consider that the section will be threaded into the barrel at this same point. (Barrel has a male thread for the cap, a female thread for the section.). Assuming you use a standard M6 tap for the section, you're losing (6mm plus 2x1mm) 8mm from your core. So you're left with a barrel wall thickness of (1.5mm divided by 2) 0.75mm. Not much!

Most kitless folk therefore opt to use an extra fine (but still single-start) M12 die, M12 x0.75. They're not too expensive (like here) and they allow better strength because you lose less core material. As an added benefit the threads look less 'industrial.

Your not related to Einstein or Plato or Socrates or Archimedes or Newton by any chance!!!!!:face::face::face::face::face:
 

trapper

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Ok guys,
richardgreenwald.com is a good place to start if your looking for kitless pen making he carries alarge range of schmidt components twists spinners clickers and the relevant taps dies and drills. I also know from an email he sent me over the weekend that he has just received a shipment from Schmidt in Germany. His prices are reasonable but do remember the cost of shipping and the dreaded 20% which HMG will rob you of at the entry point............ sometimes you'll get away with it if the value of the shipment is less than £100.
I do have contacts in this country willing to manufacture triple and quad start threading taps and dies they will do one offs but very expensive 20 or more and the cost becomes competitive to USA prices
 

clumsysod

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Thanks for the pointers and the maths but I will be using what is at hand or can be begged / borrowed.
I will certainly not be investing in any triple or Quad threading tools.
Nor a metal turning lathe.
The whole experiment is a suck it and see exercise.
However if it is such a raving success as my bling pens are :nonono::nonono::nonono:
I may progress to bigger better faster more. :ave_it:
The information above will certainly be useful to anyone else who may wish to pursue this avenue.
 
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