October 22, 2016

Tenkara Rod Hack -- Making a zoom rod.

For some time now I've wanted to see if I could make a multi-length tenkara rod out of a fixed length rod. I know that you can fish a fixed rod at a shorter length by collapsing the section next to the handle. But this is only partly effective since the section will slide outwards upon casting, as well as rattle when collapsed. So I wanted to try to fix it in place when it was collapsed and make a "proper" zoom rod.

I generally prefer fixed length rods, but I do have streams where the increased functionality of a multi-length rod comes in handy.

For this project I chose a rod that could be modified easily, and didn't cost too much. It is the Allfishingbuy Hirame-L-3608. This 360 cm rod is a Chinese copy of a Nissin tenkara rod, probably the Prosquare or Kawashi, and it is a great rod. It is readily available, affordable, robust and casts a #2.5 level line really well. I think it is much better than many of the Chinese-made entry level rods that are available and which I personally find too stiff for effective level line tenkara.




As with most fixed length rods, the Hirame's candidate zoom section is shorter than the handle section and therefore can't be readily grabbed for extension. Therefore, to make it "stick out" of the handle section a butt cap post must be made long enough to effect this change.

For most of my zoom rods, the butt cap post is short and has O-rings which hold the zoom section firmly. This is a good design but it would be more complicated for me to try to produce, therefore I elected to go with a design similar to what Gamakatsu has in its Multiflex Suimu rods. In these rods the zoom post is a tapered rubber cone. The zoom sections slip into the cone and hold snuggly by friction. I like this design because no O-rings have to be used and the post's tolerances don't have to be so exact. The taper of the cone makes it easy to fit the zoom section with the proper amount of friction.

Zoom post from the Gamakatsu Multiflex Suimu 40

For materials I chose wood. It is readily available, is easy to work with, and is forgiving. I don't have a lathe, but I do have a drill press (a most useful shop tool). I bought a simple lathe accessory for my drill press off Amazon which effectively turns my drill press into a vertical lathe. I bought some inexpensive lathe tools: mini lathe chisels, a lathe caliper, and precision digital caliper, all off Amazon for less than you'd think.





I took the butt cap and removed the rubber bumper. I measured the inside diameter and used this measurement for the base of my post. I then measured the inside diameter of both the opening of the handle butt and the zoom segment.



For wood, I chose a fir dowel, which I got at Home Depot. Fir is a soft wood and easy to modify. I chose a dowel just slightly larger than the base of the zoom segment. The dowel is already in a cylindrical shape so all I had to do was transfer the measurements I took with the digital caliper to the wood using the lathe.

I set up the drill press lathe attachment, centered the dowel and placed the tip of the dowel in the drill press's chuck. It fit perfectly. I turned on the drill press causing the dowel to spin nicely without wobbling. I adjusted the lathe tool rest and used a pencil to mark the locations on the dowel where I needed to remove wood.



I then used the lathe chisels to remove the needed wood. It didn't take but 2-3 minutes. I used the caliper to make sure the diameters were correct. The tip of the post was made slightly conical and tapered up to a size that would act as a stop for the butt of the zoom segment. I then lightly sanded the post while it turned on the drill press.

I took the post off the press and cut the ends at right angles. I then fit the post into the butt cap - perfect, and into the zoom segment -- perfect again! Just the right amount of friction. Wood (because of it's fibers and cellular structure) is grippy but not too grippy.




I then used Gorilla glue to attach the post to the inside of the butt cap, clamped it and let it dry. After it had dried I screwed the butt cap into the rod handle and tried the zoom segment out. Since the post was about 4 inches long, it made the tip of the zoom segment stick out of the tip of the handle section about 1.5 inches; easy to be able to grab and extend. The zoom mechanism was perfect with great seating of the segment into the post, yet easy extension too.

When the zoom section is collapsed, there is a small space between the tip of the handle segment and the zoom segment. This slight space (0.1 mm) was enough to cause a click when casting. On most zoom rods there is a friction tape or slight bulge of the segment at that location making a tight fit.

Since I didn't have the friction tape (or know where to get any) nor could I modify the zoom segment, I used thin build rod finishing epoxy to add a little layer to the zoom segment right where it sticks out of the handle section. But try as I might (very small amounts thinned with acetone and warmed), I could not get thin enough of a layer to work. So, after a few tries and fails, I once again removed the epoxy and used Sally Hansen Hard as Nails in a few thin coats to built up to the correct thickness. This worked really well. It is easy to work with, water proof and easy to apply in very thin layers.

The epoxy attempt

After allowing the Sally Hansen to dry completely, I assembled the rod. The butt post held the zoom section perfectly and the Sally Hansen finish made a snug connection at the tip of the handle section too. In it's short configuration the rod is 320 cm. When fully extended (zoomed out) the rod is at it's native 361 cm. It casts a #2.5 level line beautifully at both lengths.

Length at short configuration


Full extension length

Since the zoom post is used to make the zoom section exposed (so it can be grabbed and extended), it's obvious that the original tip plug is no longer useful. No worries. Buy a Fuji universal tip cap and use it. It works better anyway!

The original tip cap won't fit now...

...so use a Fuji cap.


So there you go. I achieved my goal of making my own "zoom" rod. It didn't cost much and it didn't take much skill to do it.

So, if you would like to use your rod as a zoom rod here is one method you could use. I'm sure there are others. Have fun! As for me, my next project is to try to make a double zoom rod for small, overgrown creeks! Wish me luck!








6 comments:

  1. Nicely done.
    As you know i'm also a lover of the AFB Hirame, a copy from the Nissin Professional Kawashi series.
    Any special reason you chose the 6:4 over the 7:3 for this project???
    Be fine :-)

    ReplyDelete
    Replies
    1. Thanks, Carlos. No special reason for the 6:4. I just wanted to try it.

      Delete
  2. Wow! Although you make it look easy, that's a major project. The only thing left for you to do is design and build your own tenkara rod from scratch.
    When we will see that blog post?

    ReplyDelete
    Replies
    1. There are too many good rods out there for me to do that. Besides, I'm just some guy with a blog, not an expert ;o)

      Delete
  3. Tom thanks for the valuable advice that you give us. I read your articles with real interest and I apply what you say. Tom you are the best. Warm greetings from Italy. Ernesto

    ReplyDelete
  4. Tom, thanks for your valuable advice. I read with great interest your articles to apply what you say. Tom you are the best. Warm greetings from Italy. Ernesto

    ReplyDelete