JB6E JoWo #6 Replacement Feed in Bock 250 Housing

Description

The JB6E replacement feed in Bock 250 housing is designed to improve the performance of your JoWo nib by increasing available ink flow and providing better regulation of the ink. These are typically used in Conid fountain pens that use a Bock #6 nib assembly, but will fit other pens that use a Bock 250 nib assembly and don’t use ink cartridges or cartridge converters. These feeds have been tested with numerous versions of the JoWo #6 nibs, including EF, F, M, B, 1.1mm, and 1.5mm steel nibs, and also some 14k and 18k gold versions.

These replacement feeds/housings will be available in four versions:

• JB6E JoWo #6 feed in Bock 250 housing in black ebonite
• JB6EW JoWo #6 feed in Bock 250 housing in black ebonite, wide ink slot
• JB6ER JoWo #6 feed in Bock 250 housing in red ebonite
• JB6A JoWo #6 feed in Bock 250 housing in clear acrylic

Please note that the ebonite and acrylic feeds I make are NOT compatible with a standard Bock 250 thermoplastic housing, as my feeds do not have the keyed flat on the bottom, and thus won’t fit into the Bock housing.  There are some pens out there that have a permanent housing in the section of the pen; these can’t be used with these replacement feeds and housings.

This design, unlike the stock JoWo or Bock assembly, is not keyed, so the nib can be rotated into the most pleasing position in your fountain pen.

Installation Instructions

You will need to remove the stock Bock 250 nib assembly from your pen. Follow your pen makers recommendations for the removal of the nib assembly. You must provide your own JoWo #6 nib for this assembly; most Bock #6 nibs will not fit.

Here is how to reassemble the JoWo nib with the ebonite / acrylic replacement feed and Bock 250 housing.

• Place the nib on the feed such that the ink slit in the nib is centered on the ink slot of the feed.
• Position the nib such that the tip of the feed is in contact with the bottom of the nib (about 4mm from the tip of the nib to the tip of the feed).
• Slide the nib and feed into the housing, making sure to keep your fingers away from the tines of the nib; never apply pressure to the tines of the nib, only to the base.
• Verify the feed is fully inserted into the housing so that the end of the feed and the end of the housing are aligned.
• Verify that the nib is centered on top of the feed. If not, pull it out, realign it so the slit of the nib is centered on the ink slot, and re-insert.

After verifying your nib assembly, screw it back into the section of your pen per the manufacturer’s instructions. Do not over tighten; finger tight is what you want, there is no need to use a tool to tighten the assembly into your pen.

A note on interference (friction) fit. The JB6E nib assembly is held together with an interference fit. This means the diameter of the inside of the housing is smaller than the combined diameter of the nib sitting on the feed. This method of fit is required so the nib and feed don’t move in the housing while you write. The initial fit may be very tight, so tight that you may have difficulty getting the nib and feed fully inserted into the housing.  If the fit is too tight for your finger strength, here are two ways to assist you getting the nib and feed fully inserted into the housing.

1. Soak the feed and housing in warm, soapy water (dish soap works well) for a few minutes, and try again. Chances are the additional lubrication will allow you to fully seat the nib and feed into the housing.
2. After you get the nib assembled into the housing, use your cartridge converter to flush the soapy water out of the nib assembly with clean water until all the soap is gone.

If the assembly is still too tight, then use this method (for black and red ebonite only):

1. Soak the housing ONLY in hot water from your tap. You can use water up any temperature that your bare skin can allow, but don’t exceed 60C (140F). Allow the ebonite to soak for a few minutes. It will enlarge and soften slightly due to the hot water and make it easier to slide the nib and feed into the housing.
2. Be careful and make sure not to burn yourself in the hot water. Insert the nib and feed into the housing and adjust as needed to align the feed and nib. Allow the assembly to cool to room temperature and it is now ready for writing.