Yes, I believe that's correct. The video person says they should point upwards.

It does loosen up a bit with use (same as the screws on sewing machine that need to be tightened once every hour or two of sewing). You might also try playing around a bit with the bent washer -- making it slightly more curved or slightly less curved. Finally, I find that it goes askew more quickly when I'm using a dull blade so you might try swapping in a new blade and see if that helps.

take your cutter to the hardware store and ask for a "lock washer". then use that to keep the nut tight.

I have the same issue. My Olfa's screw wouldn't stay tight. My DH looked at it and said that it looks like it is worn out. Shouldn't be surprised, huh? The funny shaped washer broke, too. I was wondering if something else would work. I hate to just throw it out! :(

I think mine finally did wear out. I'm sad too, so I bought another Olfa :) (and a Fiskars) when I was in the states.

I found out if I push down to hard on my cutter when cutting the nut will loosen up

I have had the same problem. I think it's time for a new cutter. Mine was at least five or six years old and just wore out.

I lost the little washer and I emailed Olfa to see if they would sell me another. They immediately mailed me another washer for free. That was several years ago and I am still using the same cutter. It works great. If you are having trouble, you might contact them.

I had the same experience as VernaL only my washer didn't wear out. When I was changing the blade the washer rolled off the table and bounced down the air conditioner floor vent, never to be seen again! Contacted Olfa and they sent me new spare parts. Very good customer service!

@ Boston 1954, I have a Fiskars that does that too, it has always done it, I should have taken it back as soon as I realized this was happening. If I don't watch it closely it will fall apart.