I have several photos of individual finger bones from yet undescribed species which might be Tupuxuara. I also have pictures of the fingers of Tapejara wellnhoferi. But I only have photos of the bones of Tapejara from one angle, in black and white and in low resolution, so I can’t really see if they are flattened out, or curved in some direction. I assume they are straight comparing to the other photos I have (unfortunately I can’t post any of those pictures here, since they are all unpublished research). I compared different drawings of pterosaur hands and they seem quite similar. The number of phalanges is the same in all pterosaurs. Including the nails, the pattern for fingers 1-4 (where 4 is the wing) is 2-3-4-4. The sizes, the widths and the shape (curved, straight, flattened) of the phalanges differ across different species. As to the proportions, I found no great differences between some drawings of Tupuxuara hands (from which I have no sources), Tapejara and Pteranodon. So I used this drawing by Wellnhofer, scaled it to mach the size of my Tupuxuara skeleton, and used it as a guide to carve the fingers.
Here are the fingers and metacarpals after carving.
These are the finger bones and nails before assembly. I already pinned the metacarpals together.
I have to turn the metacarpals a bit, but this is how the fingers will be assembled.
Here are Tupuxuara’s claws after assembly. I am using pins to test, but I will later keep the fingers and metacarpals together using some cartilage (silicone rubber). If I use pins all the time it will weaken the foam.
Now I placed the metacarpals back on the skeleton with the claws in place.
Here are some other angles showing the left hand.
This is the right hand.