I keep being asked questions about fitting a new sac in a lever fill pen, so here goes: this is a Swan SF230 in need of repair.
For a start, the section has to come out. This is a black hard rubber pen so don’t soak it. Personally, I never soak any pen to take the section out. Dry heat is the way to go, and I’d say always use heat. It expands things and softens them a little, and makes a cracked barrel much less likely. These Swans are friction fit. I just pull the section out with my fingers. Latex or nitrile gloves help by giving you a better grip. Some people use section pliers.
The section’s out and you’ll need some tools to remove the remains of the old sac. I use a dental pick to get into the barrel and a pocket knife to chip the old sac off the peg. Mostly, sacs are desiccated and crumble at a touch but sometimes they can assume the consistency of part-dried glue or very stiff chewing gum. Clearing the barrel takes longer with a sac like that.
Once you have the barrel and peg cleaned up, the next move depends on the state of the nib and section. If the nib is badly offset or damaged, you will have to drift it out. That’s where the knock-out block comes in. Most of those you get to buy are fiddly little things that tend to be unstable. It’s best to make one yourself if you can.
In this case there’s no need to remove the nib, and it’s best not to take it out unless you have to, as re-setting a nib isn’t a trivial task. It needs a good flush to remove old ink, and that’s where this bulb is so useful.
When that’s done and you’ve dried the exterior of the section, you’ll need an appropriate size of sac – 18 in this case – and some shellac. A sac spreader is optional. I like this pair of old dividers with the points cut off and ground smooth.
Measure the sac and cut it to the correct length.
Get a good coating of shellac on the peg and fit the sac. Then apply some pure talc. I see a lot of “repaired” pens where this step has been missed out. Don’t. It’s significant. Without a covering of talc the latex sac will stick to the pressure bar and it will shorten the sac’s life considerably.
Let it dry. Half an hour will do it. Then reassemble and give the pen a good clean up.