91mm SAK blade layer backspring options?

[SteveP]

I've acquired a 91mm serrated blade and would like to build a custom SAK with two blade layers - non-serrated large and small blade, plus serrated blade and something else. This will be my first mod.

So I have two questions for the experienced modders here:

1. Can I put a backspring on a knife blade layer that doesn't have a corkscrew or Phillips? I'll leave the corkscrew on the non-serrated blade layer. I'm thinking I'll have the serrated layer more towards the middle so wondering what I can use as a backspring.

2. Besides the small blade and the combo tool, what else can I pair with the serrated blade?

Thank you for your suggestions!

[tattoosteve99]

I've acquired a 91mm serrated blade and would like to build a custom SAK with two blade layers - non-serrated large and small blade, plus serrated blade and something else. This will be my first mod.

So I have two questions for the experienced modders here:

1. Can I put a backspring on a knife blade layer that doesn't have a corkscrew or Phillips? I'll leave the corkscrew on the non-serrated blade layer. I'm thinking I'll have the serrated layer more towards the middle so wondering what I can use as a backspring.

2. Besides the small blade and the combo tool, what else can I pair with the serrated blade?

Thank you for your suggestions!

Yes you can use a back spring from another model that doesn’t have a back tool. I’ve done it before. Takes some work but doable.
The second one is all up to how far you are willing to go with modding. The thickness of the spring makes for that decision. A larger spring will accommodate different tools.

[Helvetica Bold]

The file from an 84mm like a sportsman will work - sits a bit low so you may have to adjust something - I normally
just file a notch in the scale/liner so I can get at the nail nick but I’m sure there is a more elegant solution. An in-line awl from a 93mm can also work. Hole is bigger (3mm) but will work with or without a bushing so depends how particular you are ;0) You will need to thin the spacer a bit as it’s wider than a small blade or combo tool.

Post picks when you’ve done it. 

[SteveP]

Thank you for your suggestions so far.

Do I need to have a tool paired with a large blade? I know there will be a gap, but is the smaller tool needed for some structural purpose?

I'm sorry if this is a dumb question. I'm brand new to modding and don't want to screw up my first one.

As for a backspring for a large blade towards the middle of the SAK, any issue with using the backspring that's meant for the knife blade layer and leaving the bottom slot empty, without a corkscrew or Phillips? I'm thinking of covering the empty slot with an aluminum cover and using it for storage.

[Jud65]

Thank you for your suggestions so far.

Do I need to have a tool paired with a large blade? I know there will be a gap, but is the smaller tool needed for some structural purpose?

I'm sorry if this is a dumb question. I'm brand new to modding and don't want to screw up my first one.

As for a backspring for a large blade towards the middle of the SAK, any issue with using the backspring that's meant for the knife blade layer and leaving the bottom slot empty, without a corkscrew or Phillips? I'm thinking of covering the empty slot with an aluminum cover and using it for storage.

Steve - I’m open to correction but I think you need the back tool (and, for that matter, the secondary tool: i.e. small blade) to ensure the full tension on the spring. If you notice when trying to click the tool into place, it’s a lot easier to get all the blades in when the back tool is absent. For example: I find it dead easy to put large and small blade in place, but once I add the corkscrew it’s a whole different ballgame, with spring tension that’s off the chart. Funny enough, I’ve been looking at modding the blade layer to put it in the centre between wood and metal saw, but face issues with the corkscrew placement (I don’t have a T-Phillips, unfortunately). I might just try it with an awl as this should provide the requisite tension.
I’d love to know exactly which backtoolless spring TattooSteve got to work with the blade layer  Cause that would be a game changer. Time for some experiments…

[tattoosteve99]

Thank you for your suggestions so far.

Do I need to have a tool paired with a large blade? I know there will be a gap, but is the smaller tool needed for some structural purpose?

I'm sorry if this is a dumb question. I'm brand new to modding and don't want to screw up my first one.

As for a backspring for a large blade towards the middle of the SAK, any issue with using the backspring that's meant for the knife blade layer and leaving the bottom slot empty, without a corkscrew or Phillips? I'm thinking of covering the empty slot with an aluminum cover and using it for storage.

No question is a dumb one.
If you can find an older model back spring that doesn’t have the back tools you can use that. As far as using one that has it, you will need something in that spot as it supplies tension for the spring. If you do decide to use aluminum make sure to use a bushing of brass or stainless as aluminum is to soft and will deform rather quickly.

[Max Stone]

Hey Steve - there are a few considerations switching things around. If you ditch the small blade, it's best to use a suitable washer to simulate the pivot of the small blade, to keep the tension for the main blade. It's difficult to switch to a single tool back spring as they have different thicknesses, which is critical to match to the tool's thickness. A good alternative for the small blade is the inline awl - a very useful tool from the 93mm Pioneer, etc. But you need to thin it down to match the thickness of the small blade.

The more creative you want to be (straying from established tool pairings and back tools), the more you'll need to make permanent changes to springs, tool pivots and even the tools themselves. I did some extreme stuff when I first started modding (like my Telluride below), but I've tended to swing back to less challenging mods, and now just play with different setups.

But it's great fun, and I'd encourage you to just dive in and try it. The worst you can do is end up with a few spare parts that you can use later! 

[SteveP]

Thank you all for your tips and suggestions. I really appreciate it.

Based on the feedback so far, I'm still leaning towards having two knife blade layers:
- Non-serrated large blade + small blade with corkscrew on back next to the back scale of the SAK.
- A second knife blade layer with the serrated large blade + (second) small blade towards the middle of the SAK.

I found a picture of an "exploded" Swiss Champ and it looks like a chisel, fine screwdriver, and reamer might fit on the backside of the knife blades without modification?

Not sure I want two reamers, but I don't have a chisel or fine screwdriver in my donor parts. Back to eBay...