Couple of questions on kitless

[Twissy]

Just finished my first kitless and have a few queries

How do you guys make it look so clean around the thread area on the tenon for the cap? I keep the MM away from there as I don't want to do any damage to the threaded area.

In the same area I noticed that some people do not have a shoulder on the body to stop the cap threading too far. My question is what stops the cap threading on too much is there a shoulder in the cap or does it just reach the end of the female thread.

Are the triple start taps bottom taps or plug taps?

I hope this isn't all too obvious, but thanks in advance.

 

[mredburn]

There were some 14mm triple taps made in bottoming but the majority were not. A coupleo f members have bought extra taps and ground them to be bottoming taps. I take a parting tool and cut the last part of the threads that are not completly formed away.

 

[bluwolf]

I'll assume you made the pen out of acrylic or something like that. You can use an old toothbrush with plastic polish on it and hold it under the threads while it's spinning.

Mike

 

[Rich L]

In the same area I noticed that some people do not have a shoulder on the body to stop the cap threading too far. My question is what stops the cap threading on too much is there a shoulder in the cap or does it just reach the end of the female thread.

Good practice is to bottom out on a shoulder and not the end of a thread.

Cheers,
Rich

 

[Twissy]

Thanks Rich. Did that today, and a nice improvement.

 

[Timebandit]

In the same area I noticed that some people do not have a shoulder on the body to stop the cap threading too far. My question is what stops the cap threading on too much is there a shoulder in the cap or does it just reach the end of the female thread.

Good practice is to bottom out on a shoulder and not the end of a thread.

Cheers,
Rich

For the most part, but you can also have the shoulder in the cap rather than the body. I dont like the looks of shoulders on pen barrels very much. You just have to turn your cap with an inner cap for the section to butt up against. I also polish my tenon with MM before i cut threads on it so you dont have to worry about polishing it. Then when i polish on the buffer i just hit the threads a bit and they are good to go.

 

[Twissy]

Cheers Justin. Using MM first makes sense...so obvious really!
I'll have to try to get my head round having the shoulder in the cap. Must mean some precise measuring/planning to avoid damaging the nib I suppose.

 

[Rich L]

Must mean some precise measuring/planning to avoid damaging the nib I suppose.

Yep! Most of what I make has the shoulder inside the cap and the front of the nib section screws up against the internal shoulder. My comment about using a shoulder was a general comment about how to design any two parts that screw together outside of pipe threads. You want axial pressure on soft materials especially instead of radial pressure with high mechanical advantage.

I've attached an example drawing of what I make to accommodate a particular Parker nib. The part is an acrylic insert that gets cemented inside a metal cap barrel. The nib comes in from the right and the front part of the section hits the shoulder I've indicated on the drawing. The nib sticks out past this part and actually past the rest of the cap barrel. The little part of the nib that sticks out past the barrel is covered by the finial. Dimensions are in inches and the threads I'm using are 4-start. Just an example ... Your pen would likely be all one piece for the cap - no insert.

Cheers,
Rich

 

[Twissy]

Thanks Rich...appreciate the diagram. I want to do some wooden kitless in the future and this will come in well handy.