I have an update and some additional information for those still trying to identify replacement screws for the Spyderco Sage 1.
I contacted Spyderco support, and they said they would look for some possible replacement screws and mail me out some if they found any. Well, they found some and mailed them out to me. Perfect replacements. I put my knife back together. Problem solved. Thank you Spyderco!
(However, I really wish they would sell replacement screws online, just in case they can't "find" any lying around - or at least publish the specs of the screws. I directly asked them the size of the screws, and they couldn't (wouldn't?) tell me that information.)
Although my problem has been solved, I still want to know what the exact specs of the screws are, if anyone can ever figure it out. I'll share what I have learned in case it helps others.
Before I learned Spyderco would mail me out some replacement screws, I impatiently and desperately bought some screws onlineTitanium Screw 4-40 Button Head 1/8" Thread Length - 10pack
, taking a gamble (and losing) that they would be good replacements. (To be clear, those screws were NOT suitable replacements)
Here's what I learned in my quest for finding the right screws:
Spyderco calls them scale screws. (I guess because they are used on the sides of the knife, vs clip screws, etc.)
They are definitely T8 torx screws.
I believe they are button head screws (as pan head seemed too flat). Diagram of screw head types
I'm thinking they are made out of stainless steel, as the titanium screws I bought had a different color.
There are 6 total screws, and the screw for the wire clip is slightly longer than the other 5 scale screws.
I originally estimated/imprecisely measured that the scale screws were 1/8" and the longer wire clip one was 3/16"; however, I was mistaken as those titanium 1/8" ones that I bought were actually a little too long compared with the 5 scale screws, but were shorter than the clip screw.
Additionally, the titanium screws I bought were skinnier than the original screws, so size 4 is too small.
Given that size 4 was too small, and just wobbled around in the screw hole,I wasn't able to test whether 40 is the right threads per inch.
Other possible screw size candidates out there:
4-40 (size 4 (2.845mm *this was too skinny of a screw) (40 threads per inch)
M3 (3 mm - almost the metric equivalent of 4-40)
5-40 (3.175mm, 40 threads per inch)
6-32 (3.505mm, 32 threads per inch)
I forgot to take a picture before returning the titanium screws, but since 4-40 was clearly too skinny,if I were to guess/try again I would probably try 5-40, skipping m3, . However, I don't even know if they would fit.
Lastly,I want to first reiterate TAKING APART YOUR KNIFE WILL VOID YOUR WARRANTY, which I did. In originally trying to put my knife back together, I stripped a screw, because I had not put the knife back together properly, and I was trying to overtighten a screw to make it go farther in to lie flush with the outside. After having receiving the proper replacement screws from Spyderco, I finally was able to put my knife back together again, this time perfectly, with the blade centered and all screws flush. From all of this experience, I have learned that if you put the knife together carefully and correctly, it goes together smoothly without having to force anything. I know this should be common sense.
In case you find yourself in a situation where all the parts of your knife are in a sad pile in a ziploc bag...
Here are a couple of PROTIPS to putting your knife back together to avoid stripping any screws etc.
1. The knife has two metal sides, with lots of holes drilled into each side. Each side has holes for the screw spacer things, connecting both sides of the knife. Notice that on one side the screw spacer things have a "D" shaped hole. The other half just has perfect "O" holes.
-Stick those spacer parts into the "D" holes first, to avoid having to try to line up later. Note, the pivot going through the blade also has a "D" shape to it on the end.
2. When screwing in the screws where the knife pivots, you have to make sure the pivot thing is centered between both halves of the knife. Otherwise, the screw on one side will poke out too far and not be flush with the outside. To do this, first just partially screw in the screw from each side of the pivot. Everything will still be loose enough for you to push the screws, which in turn push the pivot thing between them back and forth to center it. Once centered, screw the screws in all the way. When done properly, you will not have to force the screws to go in deep to be flush. They will just be flush with normal, comfortably tightening, and the blade will be perfectly centered due to the even tightening of both screws. Also, if you over-tighten, the blade will be hard to open.
3. Remember, the longer screw is for the wire clip
Hope this helps.