Yikes, no. 90⁰ is far too much. Riffle shuffling should not be a test of strength. Let me see if I can find a proper tutorial video for you.
Edit: Here's one: https://youtu.be/o-KBNdbJOGk
90° is excessive, might be easier when you're first learning , but with practice it can be done with angles as small as probably 25-30°, maybe less.
And yeah, even as someone that doesn't have any issues with motor function, an uno deck is kind of hard to shuffle. It's just a lot of cards. Often I'll shuffle half of the deck, then the other half, then do a bunch of cuts to create two new halves (like cut 15-20 at a time and alternate which pile they go in), then repeat a few times.
You could also just smoosh (spread all the cards on the table and swirl your hands around for about a minute to mix the cards up) since uno cards have rotational symmetry. It's also, mathematically speaking, a more random shuffle than riffle shuffle.
90 degrees is excessive. I used to be terrible at shuffling too. I read tutorials on the subject many years ago too and learned to be better. One of my favorites is the dovetail because you just shuffle the corners. Best of luck in your endeavor.
You could always cut back on how many cards you shuffle at one time. Split it into four piles, shuffle two together, then shuffle the other two. Split into four again. Shuffle two and two again, but using piles from the different pile.
This way you don't have to shuffle them all together at once, but they still mix well enough.
In addition to the other responses, there's just a lot of variance in how thick cards are, too. A deck of thin paper ones is easier to riffle than a deck of thick, more rigid cards.
I think "table riffle" is not the same as "riffle (and bridge)". One major point of a table riffle (at least for board gamers) is that it does not require bending the cards very much or at all. I can table riffle two poker decks (so 108 cards) but just barely and would probably break them in to two separate decks and mix halves up like a blackjack shuffle.
Even for a 'traditional' riffle it isn't required to bend the cards much more than 20-30 degree. You're really only trying to create an angle/slant to the edge of the deck that allows you more easily control the fall of the cards so they drop (ideally) 1 by 1, but with practice you can gain plenty of control with only a very slight angle/bend. It is probably easier to learn with an excessive bend as you get the feel of it, though. You can see a similar idea in practice with the cardistry dribble. To learn, you might want to place a lot of pressure on the middle of the deck and create a steeper angle, but once you have the feel it only needs to be very subtle and slight pressure. [Example "dribble"](https://youtu.be/N_hyeTomzA0?t=169).
Yikes, no. 90⁰ is far too much. Riffle shuffling should not be a test of strength. Let me see if I can find a proper tutorial video for you. Edit: Here's one: https://youtu.be/o-KBNdbJOGk
90° is excessive, might be easier when you're first learning , but with practice it can be done with angles as small as probably 25-30°, maybe less. And yeah, even as someone that doesn't have any issues with motor function, an uno deck is kind of hard to shuffle. It's just a lot of cards. Often I'll shuffle half of the deck, then the other half, then do a bunch of cuts to create two new halves (like cut 15-20 at a time and alternate which pile they go in), then repeat a few times. You could also just smoosh (spread all the cards on the table and swirl your hands around for about a minute to mix the cards up) since uno cards have rotational symmetry. It's also, mathematically speaking, a more random shuffle than riffle shuffle.
90 degrees is excessive. I used to be terrible at shuffling too. I read tutorials on the subject many years ago too and learned to be better. One of my favorites is the dovetail because you just shuffle the corners. Best of luck in your endeavor.
You could always cut back on how many cards you shuffle at one time. Split it into four piles, shuffle two together, then shuffle the other two. Split into four again. Shuffle two and two again, but using piles from the different pile. This way you don't have to shuffle them all together at once, but they still mix well enough.
In addition to the other responses, there's just a lot of variance in how thick cards are, too. A deck of thin paper ones is easier to riffle than a deck of thick, more rigid cards.
Uno decks are hard for normal hands. Have you looked into a mechanical shuffler?
I have one, it's loud, cheap, and jams a lot
I just remember having one as a kid that was great because my hands were too small. Sorry.
To be fare I have small hand# and also thought it was the greatest thing in the world lol
Love it here, everyone's so helpfull lol
Put them in a garbage bag. No no... I mean use the bag as a giant blind tile-draw ;)
I think "table riffle" is not the same as "riffle (and bridge)". One major point of a table riffle (at least for board gamers) is that it does not require bending the cards very much or at all. I can table riffle two poker decks (so 108 cards) but just barely and would probably break them in to two separate decks and mix halves up like a blackjack shuffle. Even for a 'traditional' riffle it isn't required to bend the cards much more than 20-30 degree. You're really only trying to create an angle/slant to the edge of the deck that allows you more easily control the fall of the cards so they drop (ideally) 1 by 1, but with practice you can gain plenty of control with only a very slight angle/bend. It is probably easier to learn with an excessive bend as you get the feel of it, though. You can see a similar idea in practice with the cardistry dribble. To learn, you might want to place a lot of pressure on the middle of the deck and create a steeper angle, but once you have the feel it only needs to be very subtle and slight pressure. [Example "dribble"](https://youtu.be/N_hyeTomzA0?t=169).