Can We Get Serious About Cracking This Retipping Nut?

[jmkeuning]

I REALLY want to figure out how to retip nibs. We have had this discussion here before, and it has gone nowhere.

 

The way I see it we need: some cash, some time, some knowledge, some time, some mistakes...

 

Start with this thread.

 

I have a price list from Heraeus. The largest alloy point that they sell is 1.6mm. One costs about 80 cents. A 1mm alloy point costs 25 cents. TWENTY FIVE CENTS!! This is for a ruthenium alloy with osmium. The problem, and this is a small problem - the smallest problem probably, is that the minimum order is about a thousand dollars. I will put up one fourth of that if I can get three other people in the game. NOTE - this grand will get us THOUSANDS of pieces of tipping.

 

Dear God, can I please figure out how to melt this stuff? How to attach it to a gold nib? Cutting the slit? I can do that. Shaping? I can do that. I need to figure out the attaching thing.

 

Getting a pen retipped by someone who knows (and there are only a few) costs $30 to $40. The materials cost a FRACTION of that. We need to get off of our arses and figure this thing out. I could say, "it's not rocket science," but even if it were, we have some rocket scientists here.

 

I am going to start moving on this, and I want some people on board. If you know what to do, and you tell me, I will retip your pens for life. I figure I will have steady hands for about 20 more years. Otherwise, I figure we can get a group together who know how to do this and we can retip pens for about $10 a pop.

 

Can someone talk about heating? Welding?

[ZeissIkon]

Can someone talk about heating? Welding?

 

Osmium-Ruthenium alloy won't really melt in anything short of an electric arc; think 5000º F, give or take (tungsten melts at least this high, or higher, also); you can weld platinum group metals with oxy-acetylene, but it's like trying to fusion weld bronze with a propane torch: the flame is barely above the melting point of the metal (and in the case of tipping beads, there's nothing you could hold the bead with to melt it). I've seen poor quality video of welding tipping beads onto nibs (linked from a post on FPN a couple months ago, it was the Sailor factory as I recall), and it appeared to be done using either an arc or direct resistance heating to melt the tip alloy and then letting the residual heat of the tip melt the gold (14 k gold melts in the region of 1500-1800º F, as I recall). There was also a "How It's Made" episode on making fountain pens a couple months ago; I haven't seen it, so don't know if it included nib manufacture, but it might be available on their web site by this time.

[Ron Z]

I know enough about retipping nibs that I am quite willing and content to let someone else do it.

[jmkeuning]

How do I convert a voltage rating to a temperature estimate. For example, if I have a 20 volt pulse arc welder - how hot will that heat when I pull the trigger?

 

As I am understanding - if the tipping material is the proper shape, or can be shaped outside of the attach-to-the-nib process, one could heat the tipping to hotter than the melting point of gold, then as it cools stick the nib to the tipping material at the right moment.

[Michael W]

We need to get off of our arses and figure this thing out. I could say, "it's not rocket science," but even if it were, we have some rocket scientists here.

 

Yeah I bet We Do!!!!

[jmkeuning]

I know enough about retipping nibs that I am quite willing and content to let someone else do it.

 

The thing is, I've put a few hundred dollars into retips already, and I have drawer with nibs that could use a few hundred more. Not only that, it's a lost art that is going to be permanently lost if some people don't figure it out.

[kps]

I've seen poor quality video of welding tipping beads onto nibs (linked from a post on FPN a couple months ago, it was the Sailor factory as I recall).

Probably

via this thread. Tipping at around 1:30.

[OcalaFlGuy]

I REALLY want to figure out how to retip nibs. We have had this discussion here before, and it has gone nowhere.

 

The way I see it we need: some cash, some time, some knowledge, some time, some mistakes...

 

Start with this thread.

 

I have a price list from Heraeus. The largest alloy point that they sell is 1.6mm. One costs about 80 cents. A 1mm alloy point costs 25 cents. TWENTY FIVE CENTS!! This is for a ruthenium alloy with osmium. The problem, and this is a small problem - the smallest problem probably, is that the minimum order is about a thousand dollars. I will put up one fourth of that if I can get three other people in the game. NOTE - this grand will get us THOUSANDS of pieces of tipping.

 

Dear God, can I please figure out how to melt this stuff? How to attach it to a gold nib? Cutting the slit? I can do that. Shaping? I can do that. I need to figure out the attaching thing.

 

Getting a pen retipped by someone who knows (and there are only a few) costs $30 to $40. The materials cost a FRACTION of that. We need to get off of our arses and figure this thing out. I could say, "it's not rocket science," but even if it were, we have some rocket scientists here.

 

I am going to start moving on this, and I want some people on board. If you know what to do, and you tell me, I will retip your pens for life. I figure I will have steady hands for about 20 more years. Otherwise, I figure we can get a group together who know how to do this and we can retip pens for about $10 a pop.

 

Can someone talk about heating? Welding?

 

Are you going to undertake this before, after or while you are building and selling bicycles in Africa?

 

Bruce in Ocala, FL

[RLTodd]

Random thoughts.....

 

I think it is one of those one really dedicated person projects. Not a group thing.

 

As far as minimum order quantities, there is usually some one out there that will break up larger minimum orders for a price.

 

Back in the days when we had shop in our school system, one could probably find two dozen people who would sign on to a project like this, but those days are gone.

 

Good luck.........

[SMG]

Ron you and I need to sit down at Columbus and chat about this. I have been thinking of doing it for a while, and just need some more information.

 

Cheers,

Sean

[Inka]

I know enough about retipping nibs that I am quite willing and content to let someone else do it.

Same here, as I've done air-gap welding and bonding on a microscopic level, I've seen how nibs are re-tipped and slots ground both automated and manually too so I know how it's done.

The procedure is simple enough, with the proper equipment and training, but the cost of equipment alone far exceeds any immediate return for the work done, so it's just not worth the initial monetary output unless you're already independently wealthy.

[hari317]

I have a price list from Heraeus. The largest alloy point that they sell is 1.6mm. One costs about 80 cents. A 1mm alloy point costs 25 cents. TWENTY FIVE CENTS!! This is for a ruthenium alloy with osmium.

 

I am interested in this endeavor, can you tell what is the grade of the tipping that you have a quote on?

[richardandtracy]

Just a thought:-

 

Why arc weld?

 

There are other, more controllable processes that are more suited for small workshop jobs.

 

The simplest & most obvious is silver soldering. This is a process that provides a joint that is temperature stable and is strong enough to be used in a model steam boiler. It is capable of running wet all the time, and silver has a reasonable life when submerged in ink (cf Parker 51 Areo breather tubes lasting 30 odd years). What is more, it melts at a temperature lower than the gold. It's possible to put head absorbing gel on the nib to prevent tempering of the gold when using a gas torch.

 

Next. It's possible to silver solder tungsten carbide, which is pretty hard and can act as the pellet. Experiments could be conducted with chips off tools for little expense.

 

Regards,

 

Richard.

[hari317]

Just a thought:-

 

Why arc weld?

 

Richard, AFAIK, it is usually resistance welding that is used to attach tips.

 

-Hari

[richardandtracy]

OK, I'll rephrase.

 

Why Weld?

 

Regards,

 

Richard.

[hari317]

Why Weld?

 

I am not an expert, and I am not into materials science, but my guess is the mechanical strength of the brazed joint will be lesser because of the soft filler material that is used. Also the brazing process will require a high degree of cleanliness to keep the surfaces wettable to make a reliable wet joint. maybe they find it easier to weld the tips in a mass production environment. As you suggest probably brazing can be tried.

 

The gold nib makers here like Mr. Ramanamurthy of Ratnamson pen uses a gas torch to weld the tips to the gold. They also have a resistance welding machine.

 

-Hari

[Tweel]

This is peanut-gallery stuff from one of the people watching with interest:

 

It's a tiny joint. Would silver solder be strong enough? And, unless there's a good way to keep a micro-dot of silver solder right where you want it, wouldn't there be a lot of cleanup to do (due to slipping/creeping solder)? Do they make silver solder paste? I know jewelers make tiny joints, but I thought that was where "home" retipping begins: with jeweler's welding gear.

 

-- Brian

[richardandtracy]

...I am not an expert, and I am not into materials science, but my guess is the mechanical strength of the brazed joint will be lesser because of the soft filler material that is used. Also the brazing process will require a high degree of cleanliness to keep the surfaces wettable to make a reliable wet joint. maybe they find it easier to weld the tips in a mass production environment. As you suggest probably brazing can be tried.

...

Maximum reasonable force = 3N (weight of 3 apples)

Assume a tip cross section of 0.5 x 0.5mm, giving 0.25mm² area.

Stress = Force/area = 3/0.25 = 12 N/mm²

 

In boiler calculations for model steam trains a 'safe' figure for the strength of silver solder is 100 N/mm² when used in shear and reasonable fluxing and cleanliness has been used. This gives a reasonable reserve factor of approx 8 (failure load of 24N or 2.5kg/5.5lbf - anyone using that force on a nib needs to be strung up!), and the silver solder joint is probably stronger than the tip if the gold.

 

Regards,

 

Richard.

[hari317]

Nice example of a back of the envelope calculation. but more than normal stresses may be encountered during the process of adjusting the nibs. Even with 1000gms mass, the force will be 9.8N, giving a stress of 39.2N/sq mm as a worst case when making carbon copies. I remember having read somewhere about a sailor pens experiment where they determine the heavy handedness of the writer before suggesting a nib.

 

The proof of the pudding is in the eating, so it can be tried, then we will know for sure.

 

Nice discussion...

[The Grim Sheaffer]

Retipping is half the problem. What about cutting the slit again - That seems to be a kept secret.