Sierra Super Button Click Issue

[RGABEL]

I have made 5 Sierra Super button click pens and have had issues with 3 of them where the tip does not fully retract into the nib. On the first one I thought maybe I trimmed the blank to short. The next 2 I made were fine (although the tip does not retract very far) but the next two had the same issue. Thinking that this kit was overly critical of barrel length I very carefully crept up on trimming the tube so I know I did not over trim it. I took an unassembled kit to see if the click mechanism had any adjustment, but it does not appear to. I swapped the ink refills between a pen that worked and one that did not and the issue stayed with the pen vs the refill. Any thoughts or ideas on this? I really like these kits, but not sure I like the idea of telling a customer they may need to "trim" the pen refill to get it work when they change ink cartridges.

 

[its_virgil]

Turn the spring around.
Check for a burr from the plating that may be hindering the refill.

 

[magpens]

Too bad you are having a problem with the Sierra Super Button Click. . It is a very attractive and reliable pen kit, in my experience.
I have made quite a few of those pen kits and have never experienced the problem you are having.

The click mechanism is the Schmidt SKM-88, which is used in several "newish" pen kits introduced over the past 3 years or so.
I have tried most of those kits and can list them if you wish.

A feature (or, you might say, limitation) of the SKM-88 click mechanism is that the refill's distance of travel is shorter compared to most other click pens that we have been accustomed to making and using.

Specifically, with the SKM-88, when you push the button to extend the refill, the refill moves out a distance of close to 0.15".
And, similarly, when you push the button to retract the refill, the refill then moves back in by the same distance.

I haven't made similar measurements for other click mechanisms, but I did become aware, in the case of the SKM-88, of the more limited range of motion so I did make a point of making measurements on it.

Now, I know that this info does not solve your problem ..... and, honestly, I don't know what WILL solve your problem.

However, if there are any issues with this click mechanism, then you, I, and other makers of pen kits should be aware of these issues.

I should also say that the distance that the refill travels has always been the same in the SKM-88 click pen kits that I have made.

I have never yet experienced that some Sierra Super pens have unacceptable performance with regard to refill extension/retraction.

So it is useful for me to learn of your experience in this regard. . . Thank you for making the rest of us aware of this.

I sincerely wish that I could offer a reason/solution, but in my experience the refill extension/retraction has always been reproducible for one particular pen, and the same from one Sierra Super Click to another Sierra Super Click.

I hope that you will continue to monitor your experiences with the Sierra Super Click pen kit, and please report any changes you notice.

In particular, if you find the reason for what you have reported in this thread, please tell us and report any remedy you discover. . Thanks.

 

[RichAldrich]

I really like the sierra super. I have been using the SKM-88 in kitless or bespoke pens with no issues.

Please caliper the length of the brass tube with the kit and see if it is consistant.

Thanks!

 

[KenB259]

I have made quite a few and have never had an issue. I know that's not much help, just. Even my experience.

 

[Jans husband]

I have had that problem Rob.
I persisted with unscrewing the nib section, removing the refill and replacing it, and at the same time twisting it a bit both ways and wiggling it about to locate it better in the mechanism.
I found that after a number of attempts, the refill seemed to locate more deeply into the click mechanism, but I have no explanation as to why it hadn't done before.
I have also pushed the extended refill hard onto a surface (piece of wood) whilst pressing the finial with my thumb that has also worked on one occasion.
I just assumed that the tolerances of the click mechanism where the refill locates are very fine, but a bit of wiggling usually works.
Also, try swapping the refill from another kit-you never know!!
Mike

 

[magpens]

@RGABEL

Rob, another possible factor ..... the click mechanism itself. . I was alerted to this last night when "playing with" an older pen with SKM-88.
It is not a Sierra Super Button Click, for which the mechanism is not actually removable. . It is a PSI Duraclick EDC which does allow removal.

The SKM-88 mechanism has attracted a kind of reverence, but it does have a weakness and might be the culprit in some cases.

The mechanism is not sealed .... tiny bits of debris can get into it, most likely at the lower end where the internal grooves can be seen in the button-depressed position. . There is a tiny, rolling ball riding up and down in the groove pattern. . . Debris could inhibit the smooth motion of that ball and result in failure of the mechanism to extend/retract fully.

The pen I was playing with definitely has failures in extending/retracting fully.
I replaced the mechanism with a new one and the operation became reliable again ..... replacing the first mech. caused return of problem.

The next question is how to further examine and correct ... I do not want to disassemble the mechanism ... there are pics on IAP of internals of the SKM-88 and disassembly is not on the cards for me.

I feel inclined to bathe the mechanism in a light alcohol solvent, while at the same time activating the button in hopes of dislodging the suspected debris. . I don't think the alcohol will do any harm as the mech is all metal.

I'll try this and report back any improvement in operation. . . Meanwhile, any further insight would be appreciated and welcomed.

@RGABEL - Edit / Update / PROGRESS

So .... I got an empty pill bottle, half-filled with Methyl Alcohol, put in the SKM-88, capped the bottle.
Then I shook for 10 seconds or so; waited 5 minutes; repeated ..... for 30 minutes.

Removed SKM-88 mechanism from bottle, blew off the mechanism, allowed to dry (?) for 10 minutes, blew off again with compr. air.
Re-installed SKM-88 in the original pen.
Clicked the push button 100 times in fairly quick succession ...... 2 failures to fully retract/extend. ( 2% failure compared to 20% previously )
Waited 5 minutes; clicked the push button 150 times; NO FAILURES ( 0% )

I would say this has successfully cured the problem ..... will do another 100+ click test later in the day. . CAUTIOUSLY CLAIMING SUCCESS !

 

[Jans husband]

Admire your persistence Mal.
Wasn't there a James Bond film where "I am invincible" repeatedly clicked Bond's pen, unaware that it was an explosive device on alternate clicks?
Go carefully on your further experimentation!!!
Looking forward to your further results and update-as always.
Mike

 

[magpens]

RE: MY POST #7 ABOVE

I said I would do another check on the performance of my SKM-88, a few hours after having bathed it in Methyl Alcohol.

I noted in post #7 that that treatment definitely improved the performance.

At this time I can say that I have done another performance test of 100 consecutive clicks and the very good performance continues.

So I am going to conclude that my cleaning (bathing) the SKM-88 as I described above DID improve its performance significantly.
And I hereby declare that experiment to be a SUCCESS. . .
It seems that bathing the SKM-88 did clear some tiny bit(s) of debris which had been inhibiting the performance as described.

One other point may be worth considering ..... there is the possibility that there could be some manufacturing variations in the SKM-88 click mechanism units resulting in differences in the performance from one unit to another unit. . . I am not speculating what those variations might be but just suggesting that perhaps we should not expect every unit to perform exactly the same as every other unit. . . Furthermore, the performance of any one unit could change from time to time . . . possibly due to some tiny bit of debris making is way into the internal groove system of the unit where the tiny ball bearing rolls/slides . . . Inspection of a SKM-88 unit externally leaves open the possibility that the tiny internal grooves could collect tiny bits of debris from time to time and that such debris can work itself out somehow. . . As a result, the performance of one SKM-88 unit could change over time.

 

[Jans husband]

QED!
Thanks Mal
Mike

 

[RichAldrich]

Great job Mal!