Thursday, May 19, 2011

Splint prototypes v1-v7

I stopped posting blogs for the past 3 weeks for various reasons; however, I've continued to iterate on splint designs. I'm now up to my 8th revision!

Why so many? Well, superglue is removed with olive oil (and other common oils) and I was refining my design and splint building skills.

I kept having adhesive failures after cooking, doing dishes or working with certain materials for splint design. Some web research revels that olive oil is used to remove superglue. I've switched to using a combo of nail hardener, nail polish and superglue... and I avoid getting olive oil on the nail.

Here is a quick recap of my previous prototypes.

V8 - May 17, 2011 8:30 AM

This is my current iteration and is working great.

V7 - May 14, 2011 10:00 AM 
The skin under the splint was starting to bother me, so I thought I'd try using a Band-Aid brand Advanced Healing bandaid. These are meant to stay on 24 hrs.

The only issue is the warm thermal plastic bonded to the back of the bandaid.

This version lasted 70 hrs (almost 3 days). 3x longer than the band-aid should stay on.

V7 - Skin irritation 

This was a very stable and comfortable design since the whole length of the splint was stuck to the back of the finger down the whole length.

The skin did start to become irritated and didn't look well when the superglue finally failed.

V7 - Skin irritation

V6 - May 13, 2011 12:30 PM 
V6 - Focus on making the nail more stable
This version focused on making something simple and rigid that was repeatable.

I started using more Closure Tape at both the distal and proximal ends. It is thin, easy to apply/adjust/replace.

This version also started experimenting nail hardener / nail polish to strengthen the nail and improve the bonding.

It ends up that warm prototyping plastic bonds directly to nail hardener without super glue. However, there was still an adhesion failure 20 hrs later after exposing the prototype to some really hot water.

V5 - Wire frame experiment
V5 - May 12, 2011 2:30 PM 
This version used 18 gauge cooper wire as an armature.

It was very thin; however, the cooper was a bad choice. It was strong, but not rigid. It could be bent with enough pressure and then would hold that shape.

V5 - At removal time. Skin showing some wear.
The skin showed some irritation after it was removed 20 hrs later.

Because of the frequent super-glue failures, I started using skin closures to hold the tip to the nail.

V4 - At time of application
V4 - May 11, 2011 2:50 PM

Attempt to replicated thin / well fitting v1.

This version was very comfortable and kept the DIP very stable.

V4 - Closeup of nail
Fingernail is showing some wear from all the prototyping. Some of the roughness is left over superglue.

Superglue failed May 12, 2011 1:30 PM.

V3 - May 8, 2011 2:00 PM

Superglue failure, so I made another prototype. This time I experimented using tubing to shape the plastic. My goal was to get straighter, stronger lines.

V3 - At time of failure. Roughness is from experiment.

This version held up pretty well. The gap between the plastic and the finger was an issue. It didn't hold the finger as rigid and put a lot of radial pressure on the nail, so the prototype was heated and pressed firmer against the finger.

The 2nd photo was taken when the superglue failed approx 26hr later. The rough texture is from an experiment to create a cradle using a fabric like plastic; but it stuck to the Thermal Plastic.

Notice the band-aids under the splint to offer some relief from moisture and pressure.

V2 - May 7, 2011 - 9:00 AM

V2 - Initial attempt was too flexible

This version was an attempt to replicate V1. Maybe make it a little cleaner.

It looks great, however, it wasn't still enough and DIP joint would flex.

V2.1 - Same splint reinforced

I attempt to fix this design by adding more plastic to the weak sections while still on my finger.

The final splint was much more solid and very robust. The back of the splint was useful in a couple of situations to protect my finger while I was getting accustomed to not using that finger.

V1 - Original design
V1 - Apr 29, 2011
This was my original attempt and for the longest time, the best.

Some of the success was because my finger and nail were still in good shape. As you'll see later, the constant re-gluing of plastic to my finger nail takes a toll.

1 comment:

TomN said...

Edit: I inverted the order of the versions to make it more readable. So instead of starting at v1, it starts at v7 and goes backwards.