Delta Flow Problem Diagnosis

[Chairman]

So I have a Delta Dolce Vita OS that has ink feeding problems and I'm apparently not the only one. Basically, it'll write nicely for a third of a page and then the flow gradually tapers off until it's skipping and generally dysfunctional by the end of the page. Works fine for another 1/3 page if I twist the converter and get some ink back into the feed.

 

After pulling the nib and feed (finding no clogs, jams, debris or anything obvious), I looked at the design. The feed is ebonite and has a small protrusion that extends into the nipple built into the section where the converter attaches. It is not the full length of the nipple though (see picture below). I took a full converter and pressed it against the end of the bare feed and ink flowed into the channel just fine.

 

Based on the above, I suspect that air might be getting trapped in the little space inside the converter nipple between the end of the nipple and the end of the feed. Does that sound plausible? Is this a design flaw? Should I go on a rant about how modern companies manage to screw up technology that worked great 75 years ago?

 

The DV OS will get sent to Delta since it's only a month old. I have an older Delta Lugdunum LE that suffers similar symptoms perhaps stemming from the same design. How to fix it?

 

http://i.imgur.com/GfauU.jpg

 

ETA:

 

ink is not sticking to the sides of the converter (and I've tried multiple converters in multiple pens)

 

have not tried to replicate this when using the pens as eyedroppers (and am not particularly inclined to)

Edited March 26, 2011 by Chairman

[fpnnm]

That picture has great detail.

 

(Until an expert chimes in ....) Mentioned elsewhere on the forum: have you tried rinsing the entire section with diluted ammonia (10:1 plain water to plain ammonia), using perhaps a rubber squeeze-bulb, and then rinsing the section again in plain water?

Edited March 26, 2011 by fpnnm

[viclip]

Is there perhaps a rough area or "overhang" within the converter nipple/piercing tube? In the event that there is an air bubble forming therein, that could explain it, a delicate polishing might help (same idea as polishing a carburetor bore).

[Chairman]

I'd flushed with diluted ammonia, but I took the nib and feed out of both pens and gave them another ammonia bath. I even tried to polish the inside of the converter nipple per the suggestion here. Same results. I even tried it using Delta ink. Same result.

 

For some reason, the ink is not making it from the ccnverter into the feed. I don't know if the pen is not breathing sufficiently and therefore a vacuum is being created in the converter or if something else is going on. Bah...

 

Any other thoughts?

[fpnnm]

Another option is to try a different brand of ink, maybe a wetter ink. Oh, did you clean out the converter, too (It may have residue issues, though this possibility seems to be remote.)?

[Chairman]

I've tried multiple inks--all normally well-behaved (Waterman, Aurora, Diamine). I gave in and filled the Lugdunum as an eyedropper and it seems to flow just as it should. Seems like expensive pens should work as designed...

[fpnnm]

One more option: use a 10X or higher-power loupe to examine every millimeter of the ink-flow channels in the feed for obstructions. Finding nothing using that option, you might consider calling the US Delta distributor, YAFA pens:

 

CONTACT INFORMATION

YAFA Pen Company

21306 Gault Street

Canoga Park, California 91303 USA

Tel: (818) 704-8888

Fax: (818) 704-8112

 

ORDERS: (800) 274-9232

DELTA: (888) DELTA-PEN

ASI: (800) ASI-YAFA

(800) YAFA-PEN

 

email: yafa@yafa.com;

 

or at the Web page.

[watch_art]

I've tried multiple inks--all normally well-behaved (Waterman, Aurora, Diamine). I gave in and filled the Lugdunum as an eyedropper and it seems to flow just as it should. Seems like expensive pens should work as designed...

 

Lugdunum??? Huh?

 

If you filled the barrel and it works properly, then your converter is probably to blame. Try a few different ones. And does it work properly with a cart? I have a problem believing that the little space in there is causing all your problems, but I could be wrong.

[sirksael]

I had the same problem with 2 of my converter deltas: a 365 and a passion. In both cases I solved the problem by putting a little ball from an empty international cartridge into the converter.

You could probably test if this would work for you by trying the pen with a cart?