Time for another glove update.
The gauntlets seems to become the most daunting task in this entire build.
Sure, I could take the easy way around and simply print the fingers and gauntlet in PLA or even normal, sturdy resin, but I wanted to have the gloves to actually work. Like me actually being able to grab things.
So, I've done a few experiments that I wanted to share with you.
I guess this post is more an adventure into experimenting than anything else. A venture into finding things that doesn't work...
Before I even got my first resin printer, I started with my old Do3D files and printed the palms, to find a good size. I got the left hand done and sized decently in flexible filament through FDM printing. Around this time, I did a lot of experimenting with the fingers, didn't like how they were, and that started the journey of redesigning them from scratch. That journey took a nnumber of turns before reaching the results you see in my previous post. More in this in a bit.
In the process of this, I even tried building the fingers in EVA foam. The results were notbad, but I was looking for my holy grail here:
After printing the finger pieces one by one in TPU, or flexible filaments, I didn't get good enough results, so I ended up making a "solid" finger where I cut it open so it was actually held together at the hinges. This proved to be a pretty decent solution, but I was not too happy with the layer lines, and as you all know, flexible filaments does not sand well. At all.
So, fast forward to the world of resin printing printing. I got myself a test bottle of eSun's flexible filaments and wanted to keep trying my finger experiments with this, since I figured that printing in flexible filaments and gluleing these on top of my donor glove, would be the perfect way.
So, after testing the new design, and testing the new finger files, I ended up making a very good version of the fingers for resin printing. I've scaled them to a good approximation for my fingers, and set out to print them. This worked fine.
I then cleaned up the fingers by removing the thin sacrifical piece on the insides of the fingers (so I didn't need to use supports)...
This was cut carefully with a scalpel, as the flexible filament does not cut easily.
Some quick test on my rubber gloved hand showed that it fits well, but has some issues:
Bending the finger immediately made the flexible resin crack. There was not enough play in this, and it was not rubbery enough to allow this.
So, another batch was made, slightly thicker, and tested with the old TPU palm:
I tried glueing down the flexible fingers with contact cement, hot glue or even e-6000. Seems nothing is sticking to this rather fat surfaced resin.
Next up: I used more flexible filaments in a syringe and used it as a glue to get the fingers to stick on the glove. That gave some results, and allowed me to test paint with some plasti-dip. A good flexible paint job on top of the flexible filaments..
However, it turns out the paint does not stick well either, as once it was dry, I could do this:
Just rubbing my fingers across removed the plasti-cip without any issues.
Now, I left some sitting for 48 hours, and the paint does stick a lot better after this, but there is still the issue of glueing the pieces in place, plus that they do not bend as intended.
The early attempts on a test glove showed that the only way I could make this happen, was if I coated the entire glove in flexible resin first, put in my curing chamber and then went to town glueing with the syringe and UV light, but this left the glove with uncured resin where ... well .. where the sun didn't shine...
Shame on you for thinking what you just did. I meant on the INSIDE of the glove, of course, closest to the skin. As all who does work with resin knows, this is not ideal.
So, from the looks of it, I will go back to an earlier idea, to print the full finger in TPU and print in fine layers and then rely on plasti-dip to remove the layer lines, if I want a flexible glove.
After all, it looks ok. Not perfect, but getting there. Jst see this comparison with an unglued flexible resin finger.
This is printed in thicker layers for testing and not coated in anything. I think it will work.
So, My next step is to print another batch in TPU, size them right and go from there. I do have a batch of fingers done in solid resin at the same time just in case. It may be enough by coating them in plasti-dip to allow things like grabbing stuff after all.
So I will leave you with paraphrasing Edison: I have not failed to make the Robocop gauntlet, I have merely found several ways of NOT building a Robocop gauntlet... and I have a pile of rejects to prove it!