Basic Disassembly, Repair & Reassembly of a Jack Knife.
Posted: Sat May 16, 2009 9:20 am
I often receive PMs and e-mails from people asking me questions about knife repairs. I thought it would be worthwhile to write a tutorial with lots of pictures to show people step-by-step how to repair a knife. From the PMs and e-mails I receive I know people are interested in repairing knives. Perhaps this little tutorial will answer some basic questions for people who are interested in knife repair but have questions regarding some of the operations and equipment involved. I have tried to keep the tools basic, though I did use my 1725 rpm buffer. I even have some of the tools available in my AAPK store. The Cutler Stiddy, spring compressor (Camillus style knife vise), small ball peen &/or jewelers hammer, and even Adrian Harris' book, Knife Repair & Restoration, are available in my AAPK store. If I am out of stock of a particular item, please feel free to PM or e-mail me and I will notify you when I have them back in stock, or check out some of the other stores here on AAPK.
The knife I am using for this project is a 3-inch Case XX jackknife that I purchased at an antique store this week. The knife had nice red bone handles but the pen blade was broken off at the tang. The main blade was approximately 1/4" short but still had plenty of life left in it. I took the knife apart, removed the broken blade and the center liner and put the knife back together. The result was a very nice small, thin single bladed knife that would fit nicely in one's pocket or purse without taking up a lot of room. The small (3") size makes this knife very sheeple friendly. If you decide to do a project such as this, please post your results in this thread.
Tools Used-
1. Spring-loaded center punch.
2. 6-inch mill bastard file.
3. 2-ounce ball peen or jewelers hammer.
4. Side cutter or end cutter.
5. Spring compressor (Camillus type knife vise).
6. Bench vice.
7. Foredom, Dremel or other rotary tool.
8. 1725 rpm buffer was Scotch Brite wheel and loose muslin buff.
9. No Scratch Pink buffing compound.
10. Drill press.
11. Drill press vice.
12. Heavy-duty lubricant such as Ultra Lube -available at http://www.usaknifemaker.com/store/inde ... b18466ea14 this is the most effective lubricant I have found for spinning pins.
13. 0.008” slackner - made from feeler gauge
14. 1000, 1500, & 2000 grit sandpaper. I also recommend incremental grits from 400 to 1000 to ensure nice smooth bolsters that will polish easily with the 3M polishing paper.
15. 1 micron (8000 grit), 2 micron (6000 grit), 3 micron (4000 grit) 3M polishing paper. Available at - http://www.knifeandgun.com/ProductDetai ... Code=3MPS1
Taking Knife Apart
1- Start with the knife, file & a spring loaded center punch. Pic #1
2- File the head of the rocker pin and rear pin flat. Using the spring loaded center punch make a deep enough indentation to start a 1/16” drill in the rear pin, rocker pin & pivot pin. Drill deep enough in pivot pin to reach about the center of the pivot pin. Pic #3
3- Using a Dremel, Foredom or other rotary tool, remove most of the head of the rocker pin. Pic #4
4- Open blade(s) of the knife and place in a spring compressor (Camillus type knife vise) to compress the back springs. Using a 1/16” pin punch tap out the rocker pin, releasing the spring pressure in the knife. Pic #5
5- With a rotary tool, remove most of the head of the rear pin. Pic #6
6- On this knife the rear pin did not go through the ends of the back springs so the springs came out at this point. Most knives have a hole through the end of the back springs that the rear pin goes through. It is necessary to drive this pin out with the 1/16” pin punch, or cut it with a razor blade to remove the springs. Pic #7
7- Drive out the pivot pin with the 1/16” pin punch, or cut the pivot pin with a razor blade. On this knife the pivot pin was small enough that drilling into the pin weakened it enough that the pin broke. Pic #8
8- Using a small hammer, drive the pivot pin from the inside back out. This is necessary in most cases as the hole for the pivot pin is tapered to prevent the pin from coming out. File down about ¼” of the outside end of the pivot pin. Pic #9
9- Using the spring loaded center punch, drive the pivot pin back in the hole. You can use the 1/16" pin punch for this, but you must be careful not to mushroom the head of the pin. I find the gentle action of the spring-loaded center punch is usually more than enough to push the pin back through tapered hole. Pic #10
The knife I am using for this project is a 3-inch Case XX jackknife that I purchased at an antique store this week. The knife had nice red bone handles but the pen blade was broken off at the tang. The main blade was approximately 1/4" short but still had plenty of life left in it. I took the knife apart, removed the broken blade and the center liner and put the knife back together. The result was a very nice small, thin single bladed knife that would fit nicely in one's pocket or purse without taking up a lot of room. The small (3") size makes this knife very sheeple friendly. If you decide to do a project such as this, please post your results in this thread.
Tools Used-
1. Spring-loaded center punch.
2. 6-inch mill bastard file.
3. 2-ounce ball peen or jewelers hammer.
4. Side cutter or end cutter.
5. Spring compressor (Camillus type knife vise).
6. Bench vice.
7. Foredom, Dremel or other rotary tool.
8. 1725 rpm buffer was Scotch Brite wheel and loose muslin buff.
9. No Scratch Pink buffing compound.
10. Drill press.
11. Drill press vice.
12. Heavy-duty lubricant such as Ultra Lube -available at http://www.usaknifemaker.com/store/inde ... b18466ea14 this is the most effective lubricant I have found for spinning pins.
13. 0.008” slackner - made from feeler gauge
14. 1000, 1500, & 2000 grit sandpaper. I also recommend incremental grits from 400 to 1000 to ensure nice smooth bolsters that will polish easily with the 3M polishing paper.
15. 1 micron (8000 grit), 2 micron (6000 grit), 3 micron (4000 grit) 3M polishing paper. Available at - http://www.knifeandgun.com/ProductDetai ... Code=3MPS1
Taking Knife Apart
1- Start with the knife, file & a spring loaded center punch. Pic #1
2- File the head of the rocker pin and rear pin flat. Using the spring loaded center punch make a deep enough indentation to start a 1/16” drill in the rear pin, rocker pin & pivot pin. Drill deep enough in pivot pin to reach about the center of the pivot pin. Pic #3
3- Using a Dremel, Foredom or other rotary tool, remove most of the head of the rocker pin. Pic #4
4- Open blade(s) of the knife and place in a spring compressor (Camillus type knife vise) to compress the back springs. Using a 1/16” pin punch tap out the rocker pin, releasing the spring pressure in the knife. Pic #5
5- With a rotary tool, remove most of the head of the rear pin. Pic #6
6- On this knife the rear pin did not go through the ends of the back springs so the springs came out at this point. Most knives have a hole through the end of the back springs that the rear pin goes through. It is necessary to drive this pin out with the 1/16” pin punch, or cut it with a razor blade to remove the springs. Pic #7
7- Drive out the pivot pin with the 1/16” pin punch, or cut the pivot pin with a razor blade. On this knife the pivot pin was small enough that drilling into the pin weakened it enough that the pin broke. Pic #8
8- Using a small hammer, drive the pivot pin from the inside back out. This is necessary in most cases as the hole for the pivot pin is tapered to prevent the pin from coming out. File down about ¼” of the outside end of the pivot pin. Pic #9
9- Using the spring loaded center punch, drive the pivot pin back in the hole. You can use the 1/16" pin punch for this, but you must be careful not to mushroom the head of the pin. I find the gentle action of the spring-loaded center punch is usually more than enough to push the pin back through tapered hole. Pic #10