Leatherman OHT mod

ComboTool · **on:** April 12, 2020, 11:39:21 AM

I remember reading a review somewhere (might have been on this site actually) that described the OHT as "Juice tools in a Surge frame". So of course I had to try...
I replaced the serrated blade with Surge scissors, the strap cutter with the awl and the saw with the blade exchanger. The short tools opposite the scissors and saw have to go of course, spacers are used to keep the liner lock depressed.
Adapting the scissors and blade exchanger is relatively easy: the pivot size is right, you mostly have to grind (very slowly, with regular tests) the side that engages the liner lock (and a bit above as well). The awl requires a litte more work but can be made to fit. One-hand operation is possible for the saw, somewhat possible for the scissors (same as on a Surge I guess), but the awl requires two hands (you have to maintain the liner lock depressed during the opening otherwise it engages about mid-way). I have an idea to solve this, I will let you know how it turns.

Wspeed · **Reply #1 on:** April 12, 2020, 02:05:34 PM

Nice mods

Juan el Boricua · **Reply #2 on:** April 13, 2020, 03:37:58 AM

Looks good, CT; kudos to you Sir!

Now, if it had the large bit exchanger and be available...🤔
Are you listening LTG!?

Sam Lim · **Reply #3 on:** April 13, 2020, 07:09:46 AM

are the pivot size the same. Taken apart a OHT before but couldn't quite remember. OHT is in serious need for an update. If they didn't just put in the cartoonish tool for the sake of tradition..

zoidberg · **Reply #4 on:** April 13, 2020, 09:04:16 AM

Think they are two different sizes Sam, guessing 1/8 and 3/16.

ComboTool · **Reply #5 on:** April 13, 2020, 12:13:00 PM

I'm not sure I understand the remarks about pivot size, so just to clarify: as you know, the OHT has two pivot sizes. The short tools on the plier side are very close to 3mm, so 1/8" is my best guess. The long tools opposite the pliers use the same size as the Surge.

Sam Lim · **Reply #6 on:** April 13, 2020, 01:30:13 PM

Quote from: ComboTool on April 13, 2020, 12:13:00 PM

I'm not sure I understand the remarks about pivot size, so just to clarify: as you know, the OHT has two pivot sizes. The short tools on the plier side are very close to 3mm, so 1/8" is my best guess. The long tools opposite the pliers use the same size as the Surge.

Ya. Thats what I meant. So far I know that the tools and the pivot screw are all of different size. How did you correct the differences? Any issues with the locking of the implements? Vertical play etc. Me too would like a blade exchanger in an OHT.

Poncho65 · **Reply #7 on:** April 13, 2020, 07:38:34 PM

Great looking mod and more what the OHT could/should be if LM chose for it to be

ComboTool · **Reply #8 on:** April 14, 2020, 09:22:39 AM

Quote from: Sam Lim on April 13, 2020, 01:30:13 PM

How did you correct the differences? Any issues with the locking of the implements? Vertical play etc. Me too would like a blade exchanger in an OHT.

No adjustment was required for the pivot diameter or the part that rests against the frame (not sure how it's called). The tool has to be ground off in two places: the rounded part on the top (doesn't have to be very precise, just to make it fit in the smaller OHT frame) and the locking surface at the back (this requires a lot of trials). For the blade exchanger, only the center part has to be modified. I lined up a Surge tool and an OHT tool on the same pivot to mark the differences, and removed the excess with a rotary tool, first with a red cutting disc and then a grinding stone for the final adjustments. The tools lock properly with no play.
The Surge tools are slightly thicker, so in theory you may want to use a longer pivot, I had no problem no problem reusing the original OHT pivots (overall the tool is about 0.5 mm thicker now than the original OHT).
Hope this helps.
Here are a few pictures to show where to grind (the bare metal shows) and the locking of the tool.

Sam Lim · **Reply #9 on:** April 14, 2020, 12:28:12 PM

thanks for the explanations! 👍

ComboTool · **Reply #10 on:** April 16, 2020, 12:44:08 PM

Posting this made me want to finish the awl mod, and I'm happy to report a success. As I said earlier, because the awl isn't designed to work with a liner lock (it's one of the inside tools on the Surge), there is a flat surface at the bottom. When opening the awl in the OHT, there's nothing to keep the liner lock depressed, so it engages about mid-way. To solve this, I have added a bronze washer to the awl, which I punched to prevent rotation (there is an indent in the awl for the original locking mechanism). Now the awl opens in one motion without needing the other hand to keep the lock depressed.

ComboTool · **Reply #11 on:** April 16, 2020, 12:47:23 PM

While I was at it, I decided to add back the small flathead. It folds above the scissors without protruding. Of course, it has to be open when deploying the scissors, but those scissors are quite cumbersome to open anyway, so this doesn't add much complication.

ComboTool · **Reply #12 on:** April 16, 2020, 12:51:34 PM

So here's the final tool selection. While it was apart I noticed that contrary to what I wrote earlier, the pivot hole of the OHT tools is slightly narrower than on the Surge tools. The difference is minimal (I hadn't noticed it before), and it hasn't caused any problem.

Wspeed · **Reply #13 on:** April 16, 2020, 01:48:32 PM

Excellent work

That is the way the OHT should be like

Sam Lim · **Reply #14 on:** April 16, 2020, 03:58:29 PM

Quote from: Wspeed on April 16, 2020, 01:48:32 PM

Excellent work
That is the way the OHT should be like

1000%

Poncho65 · **Reply #15 on:** April 17, 2020, 01:25:46 PM

That is a much better layout than stock

Syncop8r · **Reply #16 on:** April 18, 2020, 01:50:47 PM

The saw is longer now too.

One of the things I like is the tools look like they were always there.

I don't know if I could give up the serrated blade though as it's my most-used tool.

ComboTool · **Reply #17 on:** April 19, 2020, 11:00:11 AM

The scissors have to go in a left-hand slot (replacing either the saw or the serrated blade of the OHT), but the blade exchanger can probably be made to work in a right-hand position, so a configuration that retains the serrated blade is possible.

Robbinsingermany · **Reply #18 on:** March 18, 2021, 08:39:44 PM

Poncho65 · **Reply #19 on:** March 18, 2021, 10:48:15 PM

Welcome to

Robbin

ComboTool · **Reply #20 on:** June 20, 2021, 02:33:03 PM

I've been revisiting my OHT mod, this time I've added a Surge bit holder and Metro's utility knife holder for Signal. The only original tool remaining is the large flathead (I keep it despite the bit holder for light prying). I guess it's the final evolution of my OHT project.
It all started as a "could I do this?" project and now it's a tool I could actually use... if only it wasn't so big and heavy