Making pen clips - HELP!

[thewishman]

I'm working with a friend and we have an idea for making pen clips from stainless steel. We can engrave and cut the clips, but neither of us has made a clip before.

The concept sounds easy, but there are some things that will complicate matters. Please add to this list, or better yet, help us solve the problems.

1. Springy-ness - how do we make sure the clip can operate as a clip?

2. Smoothing edges - we'll be cutting with a laser, is there a simple way to get smooth edges?

3. Bending angle - 90 degrees won't quite work.

4. bending a foot - do we need to add a slight bend where the clip ends?

If we can get the details worked out, that will clear a huge hurdle to making almost all of the parts of a pen custom. No more 50,000 minimum clip orders.

 

[low_48]

1) I think that will depend on the alloy of stainless steel. Not certain about that, but pretty sure it will have to do with the hardness. Sorry, can't give you a recommendation.
2) You'll have to sand and polish the edges
3) A press or sheet metal box brake will let you bend to any angle.
4) I think this will be the toughest. Pretty sure the big boys do that in a die, maybe more than one.
It's not going to be easy.

I'm working with a friend and we have an idea for making pen clips from stainless steel. We can engrave and cut the clips, but neither of us has made a clip before.

The concept sounds easy, but there are some things that will complicate matters. Please add to this list, or better yet, help us solve the problems.

1. Springy-ness - how do we make sure the clip can operate as a clip?

2. Smoothing edges - we'll be cutting with a laser, is there a simple way to get smooth edges?

3. Bending angle - 90 degrees won't quite work.

4. bending a foot - do we need to add a slight bend where the clip ends?

If we can get the details worked out, that will clear a huge hurdle to making almost all of the parts of a pen custom. No more 50,000 minimum clip orders.

 

[workinforwood]

Yea you need a bend on the end for sure.

Think about how it's made and then how can you downsize it.

Drilling small holes for a retainer ring is foolish. What you need is a punch press, punch the inner and outer diameters of the ring at the same time.
You also need a press to cut and shape the clip, preferably at the same time.
You can buy small hydraulic presses for a couple hundred bucks each
Need a machine shop to fabricate a die and press cutters for it
Need to create a die basically, to position the clip to the ring for welding
Need a good affordable welding process.

This stuff is expensive..what I am talking about could run 5-10k, but it is small scale repeatable and safe production. I would go to a tool and die maker to discuss all your needs. This is what they do and do very well.

 

[thewishman]

Thanks, Rich and Jeff. My friend has a very nice laser setup and cuts 1/4 inch aluminum and 1/8 inch stainless steel, so the cutting can be any shape. In fact, we could offer custom clips for sale to offset the costs.

It is the post-cutting processes that I'm trying to figure out. No drilling or welding should be needed, but the bending and the finishing are tough enough.

 

[wyone]

If you are plating the parts, they used tumblers a lot to take off rough edges of metal. I am not sure they are actually called tumblers but they use a vibratory table that the item to be finished is put into, along with an abrasive of some sort. I think they even use walnut shells to prevent damage. A bit in that and they are shiny and ready for plating


I agree about the punch though. It would be way more efficient to punch rather than cut the clips. It would be a double shot punch, the first one cuts the shape, the second forms the 90 degree top and the bend at the bottom. Then off to the finish stages

 

[Ed McDonnell]

You might want to investigate vibrating and / or tumbling for the smoothing and polishing.

Bending is not trivial. Stainless will work harden so you have to get the bend right the first time and not dawdle during the bending. Tempering metals to get the right degree of hardness to "spring" without being so brittle they break is something I'm trying to learn about now. It is way more complicated than I expected when I first decided to investigate it. I have to wonder what the heat from the laser would do to the metal that might complicate things for you even more.

You need to figure out your desired inner radius and a way to achieve that during bending. You don't want to try for (or end up with) anything approaching a sharp 90 degree angle at the bend.

However you decide to end your clip, you want something that will allow the clip to easily move over whatever it will be clipped to. An angled foot is one solution. A small rounded standoff is another.

Rich L has posted good information on techniques and tools he uses in a couple different threads. See his latest thread on "slipstream" where he provided search terms for the additional threads if you haven't checked them out already.

Good luck.

Ed

 

[thewishman]

A punch is a nice way to make just one style of clip - with a high initial cost. Maybe I'm all wrong, but cutting eliminates that cost and the restriction of just one style.

The aim of this project is to make smaller runs of custom clips, not to efficiently make thousands of the same clip.

 

[workinforwood]

There was a time I wanted to be in the pen clip business. I just got so busy with so many projects I couldn't persue it. I rather envy you if you do it because I love the mental challenges of creating a good product but at the same time doing it economically. A delicate challenging balance.

I believe I saw on tv, best way to polish small parts of stainless is tumbling with plastic beads.
Right now I am envisioning my buddy skip rat, cleaning out a metal 5 gallon pail...dismantling a bicycle for its sprockets and hooking up an electric motor with one of those oddball European plugs on it, to tumble the parts.