Crack Repair on a Chitlangi

[Daniel Koster]

I finished this one for DrDan a couple days ago and thought I should share how it went. Seems useful to the forum as a whole.


DrDan ordered a special Chitlangi with engravings on the bolster and handle(purpleheart). Unfortunately, when it arrived, it had a massive crack running 3/4's the length of the handle. happens....and when it does, we make lemonade.


There's information in the archives on how to do this fix and it's been discussed here many times - this is in no way "new information". However, probably for the first time, it's going to get spelled out one part at a time - always makes more sense that way.





Ok. Here we go!



First thing I do is get everything set up, ready to go.

Here you can see the khukuri in a vice, ready to be sanded. The sanding strips I use can be bought on a roll, 1 inch wide from Harbor Freight for just a few dollars and last a long time. The piece of leather is to protect the blade from the vice jaws. Fortunately, mine are wood, but I take extra precautions anyway.

You can also see the crack from this far away....yikes!








Here you can see where I've just finished gluing up (I know...kinda out of sequence here...but play along...).

1 - styrofoam bowl & popsicle stick for mixing up epoxy
2 - High output lamp about 2-3 feet away from what I'm working on. No matter how bright you think it is in your kitchen/garage/whatever, you still need this in order to do detail work. Makes a huge difference in the end result.
3 - Acetone - for cleaning epoxy off the blade and bolster after glue up. What you can't see is the jar of Mineral Spirits I keep around for taking off the red rouge and finish that the kamis put on the khukuri.
4 - Exacto blade - for fine detail work.
5 - Acraglas - can also use epoxy.











Now it's time to get going. I begin by sanding the handle shoe-shine style with the long strip of sandpaper. I do that only to remove the finish. Once it's removed, I sand "with" the grain the rest of the time.

In this pic, you can see what I'm putting together to begin glue up. If I just mix up some epoxy, I'll end up with a big yellow streak down the handle.....

So, what I need is purple dust. Rather than try to collect the dust falling as I sand (anybody got an extra hand lying around?) I take a piece of scrap purpleheart and sand on it for a while to make some dust. Then I put it in the mixing bowl.

1 - purpleheart + 60 grit sandpaper
2 - Acraglas - 2 part epoxy gel
3 - "Craft" sticks.....cheap at craft store, comes in a bucket.
4 - Collected purple dust







In order to make a clean glue-up, I need to take the exacto knife and clean the "wound" of any gunk, splinters, etc. so that the glue will have a smooth surface to cling to. I use the back of the blade mostly to clean it out, and switch to the front of the tip where the crack is thin.

[Daniel Koster]

Now, let's take a closer look at mixing up the epoxy.


Acraglas is different than other epoxies, one of those differences being that you have to mix it for 4 minutes before you can use. Not "mix it and wait 4 minutes"....."mix it for 4 minutes straight". It will take on a taffy-like consistency - that's when you know it's ready.

If it's cold, it takes longer...be sure to allow for this.



The first pic is the 2 parts separated.










4 minutes later, I have this:








Here's a closeup to let you see the consistency and color.








I've tried to avoid the dust the best I could.....




In this pic, I've mixed in a bit of the purple dust...






....but it's not enough, so I keep adding more until I get a more purple consistency.

Acraglas is not a fast setting epoxy, so you're ok to take a few minutes to get it right. I think I ended up taking 10 minutes, with trying increasingly thicker mixtures of dust as well as taking the pictures, etc.


Here's a purple closer to what I need.






It's pretty close....I'll add a little more and glue it up.

[Daniel Koster]

Now for the fun part...


Using a combination of the Craft Stick and an exacto blade, I fill the crack with colored epoxy. I use the craft stick to apply it, and the exacto to push it in. Then scrape off the excess and go again....and again....and again, until it's filled up. This crack was about 1/4" deep and took quite a few passes.


Make sure to do a good job cleaning up the excess....less you have to remove later and be sure to keep it off the bolster. If you're sloppy....run some masking tape around the bolster to keep it clean.

Once you're done applying the glue, you can use Acetone (on a rag, or with a toothbrush) to help clean off the little bits of epoxy.

Be sure, though, to leave a little "hump" over the crack. Filling a crack with epoxy is tricky because sometimes it "slurps" the epoxy more one place than the others. So, leave some excess on the crack to allow for that. As expected, that's exactly what happened to me this time. Thankfully, I left enough to account for it.


Here's a pic showing the crack it all it's glory:






You can see right off the bat that I'm going to run into some troubles filling a crack that not only impacts the rings, but traverses right through the engraving. Tough, but not impossible.




Here's a pic of it glued up and drying. Be sure to leave this overnight....24 hrs would be better.





You can also see I left some excess in the rings area to "build it up" a little. We'll carve that back down later.




After it has completely dried, I go back over it with some 240 grit sandpaper to remove the excess and smooth it down.

You can see that even though I did the best I could, there is still quite a bit of excess in the engraving area that needs to be cleaned out.








Using the exacto knife, I carefully shape the rings to make a smooth transition, and I cut the grooves back into the engraving area. With a steady, patient hand, it's not that hard.

Here's a close-up after I've cleaned it out a bit.






Not too bad, eh?



Well, the last thing on the list to to help this crack look a little more like the wood around it.

I do this by getting red, purple and black permanent markers and making "grain marks" along and over the crack. When all is said and done, this will go a long way toward helping the crack look like a dark bit of grain.




I ended up going over this area probably a dozen times....building it up "little by little". It does wipe off slightly (doesn't come out as strong as it looks here)

[Daniel Koster]

Whew...that was definitely the tough part.


After getting the color markings I want on the epoxy, I carefully sand the handle starting with 240 grit, then 400, then 600, then 800. I use the 3M Gold No-Load sandpaper....great for this kind of thing. Expensive and hard to get...but lasts so much longer.

After getting the handle down to 800 grit and baby-smooth, I'm ready to finish it up!



Now I just get some Minwax Wipe-On Polyurethane sealer and start building up coats of the Satin Finish flavor.





(pic of Clear Glossy flavor)



I've found that even when I want a glossy finish, it's better to start with Satin. The glossy only lets me put 3 or 4 coats before it's "done". I want more penetration than that (to ensure it is completely sealed) so I put on probably 10 coats the first day. Wipe-On type finish is great - no mess, no goop, no waiting hours for it to dry. Just apply it with a cloth, wait a few minutes, do it again. Like I said, the first day gets quite a few coats and then I leave it overnight to set up.

The next day I'll do another 10 layers of Satin and let it sit again overnight.

On the third day, I'll do another 5-10 layers of Satin until it's clearly starting to require more than an hour to dry.

At that point, I either leave it alone, or in this case, switch to glossy. 2 or 3 coats a day until I get the finish I want. That sits for a day to make sure it is 100% dry.


Then as a last layer of protection I apply some briwax, let it sit 10-15 minutes and buff it off with a soft cloth.

Glossy and super-grippy, but not too shiny. Perfect!



Here's a pic of the finished handle.

You can still see the crack (no way to avoid that except inserting a shim in there) but it looks like a long piece of dark grain, rather than a big creme-colored stripe.




Nifty, eh?


The nice thing about this polyurethane finish is that it really exaggerates the colors and the contrast. Literally "wakes up" the wood.

I used the same exposure settings on my camera for all these pictures, and did the same color adjustments in Photoshop for each one. It does look a little "hotter" upclose than it really is....but this next photo is color-correct...and you can see it's quite a bit more "alive" than before.







Just for fun, I took detail pics of the scabbard chape.












Overall this was a fun project. And of course, it'll slice paper.




Thanks for lookin'

[Daniel Koster]

Feel free to ask any questions....I'm sure I skipped over something.




Hopefully some of the new guys here will be able to make good use of this thread. Enjoy!

[cognitivefun]

Dan, you are absolutely amazing. I can't adequately express my admiration and appreciation for your contributions. Thank you so much.

[raghorn]

Another nice tutorial, Dan! I have a Kobra handle I've been meaning to mend, now I have a good idea of how to proceed. Thanks!

[Svashtar]

Dan, you are a real master! Nice work. I would have ended up with the crack sealed OK, but it would have looked like glue in a crack and not a grain line. Almost OT question though: I have never seen such nice engraving on the chape. Any info on that work?

Thanks,

Norm

[yiterp]

excellent work--thanks for the step by step--was great

[Green Ice]

Thanks Dan. This should work for a stag grip that I need to repair.
Ice

[BruiseLeee]

What happened to Drdan? Haven't seen him in awhile.

[Daniel Koster]

He's been on vacation.....lucky guy.


Norm - I'm sure DrDan could give you more info....all I know is that everything was customized "on request"....they did a really nice job. Great fit, nice karda/chakma (engraved too)....everything - real nice. Just a big ugly crack. But not anymore.

[BruiseLeee]

Are you still making knife handles? If so, I might have a project for ya.

[Ad Astra]

WOW, Dan, that was great. I have a purpleheart JKM- I should refinish like that to bring out the subtleties in the wood.

Fantastic job!


Ad Astra

[Daniel Koster]

Yes....still making knives....and their handles too....

But have a little backlog to work through....

[Yvsa]

Impressive work Dan! Me Likey!

[Drdan]

I'm back... I was in the Caribbean for 3 weeks, and am getting caught up now with things on the home front here in Italy...

The Chitlangi was a special order, and I asked Uncle Bill for a purpleheart handle and some engraving on the chape as well. I agree with Norm that the engraving came out really nice; better than my expectations really. It's such a nice touch that H.I. should offer an engraved chape option. Unfortunately, it would complicate things more than U.B. probably wants to.

When Dan told me of the huge crack, I was a bit concerned, but he told me he could do a great repair job, which he did. Not only did he mask the crack well, but he did a beautiful job of showing off the handle's grain. Perhaps you can't see other things Dan detailed; he completely tweaked the blade and gave the edge a pristine convex edge (he calls the service "The Works").

Dan, thanks; you do great work! I might just have a special project for you in the near future.

[Big Bob]

Thanks for sharing this with us Dan. A few questions: I take it you sand the finish off before using the mineral spirits on the rouge? When you put a polyurethane finish on a handle, what do you do for routine maintainence (to keep the handle from cracking without ruining the finish)?

Bob

[Daniel Koster]

Mineral spirits first
Then sand the remaining finish off
(saves on sandpaper....the rouge gums up the paper....)


Polyurethane seals the wood by filling all outside voids, grain, etc. Especially the glossy stuff. There is a thin layer of it on the outside of the handle.

In the past, polyurethane has gotten a bad rap - people saying it's prone to crack, etc. That is actually misplaced blame. The blame lies in lacquer and varnished finishes. The minwax is neither. It is also a wipe-on finish...penetrates and seals (vs. just sitting on top). It stabilizes the outside of the wood to prevent cracking.

Is it crack-proof? I'm sure you could get the handle to crack by submitting it to repeated ultra-high and low moisture/humidity changes...eventually it would give....any natural material will give. But I'll give this finish a 99% crack-proof rating. Tung Oil alone would be about a 60-70. Boiled Linseed Oil - 70-80. Tru-Oil 80. (YMMV)


I've refinished quite a few khukuris (approaching 200 I think...) and this is the best finish I've come up with to date. The only thing I might do different would be to start with some Tung Oil to penetrate first, and then seal with polyurethane.


To maintain it - all it needs is an ocassional waxing. Perhaps once every other year, if you use it a lot, you could add another coat of glossy for additional protection. I don't recommend going too thick.

[Lion's Roar]

Excellent work!!! That's one heck of a repair job! I can barely see the crack after the repair.