Everything but the nib!

Signed-In Members Don't See This Ad
mototrev

mototrev

Member
Joined
Oct 12, 2013
Messages
20
Location
Melbourne
Beside a simple spoon feed one of the nicest I've come across is Nathan from Noodle's Ahab flex pen feed. Simplicity personified! His philosophy is similar to mine, as I am a compulsive tinkerer I appreciate the infomation shared. So I must give credit where its due and encourage folk to look at the wonderful information he has freely shared here:

https://www.youtube.com/watch?v=jXfdgnxoT4M&feature=c4-overview&list=UUMQ_i8QT7pStL2NCsWaiPfg

I would encourage folk to give it ago.

I used Ebonite for the feed, barrel & section.
A few mods to my myford to help with indexing.
A dremal tool mounted to a vertical slide to enable 3 axis movement
HSS 0.4 cutting discs (0.2 or 0.3 wold be better)
The nib is a Jowo
Clips and bands in brass

The finished pens:





A bush with 3 slots to hold the feed and apply some pressure so it won't move:



The dremal set up:


An indexing plunger with 24 holes in the chuck plate (24 is a good number with some good factors, I would have prefer ed 60 holes....but space would not allow it and this attachment was made several yrs ago. :



The finished feed with breather in brass tube, note plastic is better as the brass can react with some inks. The feed is adjusted by deepening the slot with a razor saw.





The finished feed instaled:



 
Signed-In Members Don't See This Ad
Trev, that's a stunning pen especially as it is so much your own work! If you are willing it would be great to get more info on your feed vital statistics. E.g. What depth/width did you cut the longitudinal air channel under the nib? How much deeper (and at what width) did you cut the capillary ink channels? Do the 'rib slots' come through into the air channel or is there some small 'land' either side of the air channel before the rib slots start? (I know the Ahab feed has the rib slots coming through into the air channel on one side but a small land on the other - with the encouragement to cut some through on that side if more ink flow is required. Noyt sure if that would be too juicy for a non-flex nib?) How did you compensate for the thickness of the nib when the feed/nib are pushed into the section?

Any further info would be much appreciated.
 
David: You have asked most of the questions that need consideration for a feed of this type to work..
A controlled leak is what the feed unit must do, too much ink and the pen gushes and blots in everywhere.
Too slow and the writing is dry or stops and skips.
Air in interchange: the replacement of air into the barrel vs inflow
This is very complex in modern pens with ink air pathway a maze of slots at different depths.
I am currently waiting on several 0.2, 0.3 & 0.4mm slitting saw blades to make finer slots. If so desired or requested I can put together a photo essay of the steps and specs.

jimjam66 said:
Trev, that's a stunning pen especially as it is so much your own work!
If you are willing it would be great to get more info on your feed vital statistics. E.g. What depth/width did you cut the longitudinal air channel under the nib?
The under side channel is 1/3 the dia. of the feed.
The nib side is tapered shallow at the point and deeper at the rear about 3-4deg.

How much deeper (and at what width) did you cut the capillary ink channels?
The channels were cut at 1.5mm spacing at a depth of 1mm. *More channels at a finer width is required

Do the 'rib slots' come through into the air channel or is there some small 'land' either side of the air channel before the rib slots start?
The channels are not the same depth around the circumference of the feed. The lands were created using the run out the cutting tool to almost touch the side of the ink channel, however, as you get closer to the point of the feed the these slots may enter into the ink channel where ink builds up.

(I know the Ahab feed has the rib slots coming through into the air channel on one side but a small land on the other - with the encouragement to cut some through on that side if more ink flow is required.
I know the Ahab feed has changed slightly from the original release to later version.

Not sure if that would be too juicy for a non-flex nib?) How did you compensate for the thickness of the nib when the feed/nib are pushed into the section?
Rather than a push fit feed I went for a screw in feed, this allowed my to make use of a shoulder on the feed to obtain nib depth in the feed and section, the feed is (1/4" 40 tpi) dia the shoulder is .008-.010"

Any further info would be much appreciated.
I hope I have explained things adequately and have not confused terminology.
Click to expand...
 
That's what I love about this forum! So many incredibly talented people so willing to share knowledge! Thanks a ton for this, Trev. I have ordered some black ebonite which should be here next week, so my next pen will be a test bed.

One more question for clarification, if you don't mind: the 'shoulder' on the feed - is that around the entire circumference rather than a shaped recess? I can't see how I would be able to make a shaped recess with the tooling I have available, so I'm hoping it's the former!

mototrev said:
If so desired or requested I can put together a photo essay of the steps and specs.
Click to expand...

YES PLEASE! :good:
 
quick answer "Yes"
It will take me a few days if not a week or so to get this done. Too many jobs that require my time. :biggrin:
Stay tuned if your interested.
 
You must log in or register to reply here.
Back
Top Bottom