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Some years ago fly fisherman Rudi Ferris came up with an ingenious idea for quickly attaching a yarn strike indicator to a leader to assist with take detection whilst nymph fishing. Rudi's idea was to use a piece of plastic tubing, about 3 or 4mm in length cut from the inside of an old dried up Biro pen to hold the yarn in place.

It works like this:

First you double the nylon leader to form a loop then feed this loop through the tubing.
You then slide the tubing down to make the loop bigger.
Now feed the yarn into the loop and slide the tubing hard up against it.
Pull both ends of the nylon in opposite directions.
If the correct thickness of yarn has been used the tubing will hold fast under tension and stay in place.

You can now pull this indicator up and down the leader to suit the water depth you are fishing and it will stay put whilst you are casting.

The finished indicator looks like this.




Now, truth be told, this can be fiddly to do by the waterside and there are commercially available tools that make the job easier. These are very expensive for what they are, as are the consumables,  so this article shows you how to make one for your own use that will cost you pennies.


The finished tool, loaded with tubing, looks like this and can be made with a few basic tools and easily available materials.




This is how you make an indicator using the tool.



Hook the leader into the slot in the tool



Slide a piece of tubing off the tool onto the leader to form a loop



Remove the tool, then put the yarn or wool through the loop.



Slide the tubing hard up to the yarn.



Pull both ends of the leader to lock the yarn / wool in place.


To remove the indicator do the same thing in reverse, storing the tubing back on the tool and the yarn in your pocket. Both can be reused later. Simple and not at all fiddly, even with cold hands.


Now, in practice, the tubing from the inside of a Biro is a little hard and it tends to leave kinks in your leader. It's far better to use a softer, thin walled PVC tubing that 'gives' a little and will be less likely to kink or damage the leader. I'll come back to that later.


The aim of this project was to make an effective tool without having to get anything manufactured, to use off the shelf, inexpensive parts that could be modified and put together by anyone. This is not rocket science, the only difficult bit was finding the correct and cheapest parts. This I have done and now you too can, in just a few minutes, knock up a tool that costs you pennies and that works as well if not better than anything you can buy.


Here's how.


First you will need these parts.




One Milward Tapestry Needle No 18

One 8mm sea fishing bead

Some 0.40mm nylon (I used Maxima 18 pound breaking strain)


I paid £1.25 for a pack of 6 needles. It is critical you use the correct size (diameter) of needle. They MUST be No. 18 for this design.


My total parts bill to make one tool was about 24 pence!


You also need a few drops of super glue – Zap A Gap is best.


Here’s how to make the tool. Remember to wear eye protection and be careful you don't cut yourself! Yes I know you are not stupid, but this is the 21st Century and you have to say that!



Clamp the needle firmly then cut a slot about 2mm wide (the width is not critical) in one side of the needle's eye as shown. I used a Dremmel type hobby tool with a cutting disk, but you can also use a very fine blade hacksaw or needle file although it's not as efficient.



Once the slot has been cut, use a small needle file or a piece of fine sandpaper to remove any sharp edges that might cut your leader when using the finished tool.



Take a short length of the 0.40mm nylon and pass both ends through the hole in the bead to form a loop. Make the loop a suitable size, this is what will attach the tool to a zinger on your fly vest.



Push the bead onto the pointed end of the needle so that the point is just short of coming though the other end of the bead. This will be a tight fit, be careful you don't stab yourself.



Trim the loose, waste ends of the nylon flush with the bead.



Apply a drop of super glue through the holes at both ends of the bead and allow to dry



That's the tool finished. As I said, it's not rocket science.



Tubing and Wool


Sourcing the ideal tubing was a problem, but I got some from a UK seller through Ebay. The seller is http://pvctubeonline.co.uk/order_online.htm. You need 1.5mm bore thin walled tubing. A couple of pounds will buy a lifetime supply for you and all of your fly fishing pals.


It must be 1.5 mm bore, soft and thin walled. This stays on the tool perfectly until it's needed and makes wonderful indicators that will not ruin your leader.


You can use any yarn, but without doubt the best thing to use is un-spun merino wool (wool that has not been spun into a yarn and has randomly arranged fibres). I have found the best colour for maximum visibility over a wide range of light conditions is fluorescent green. Again a few pounds will buy a lifetime supply. It's probably worth buying a few different colours and using the one you like best.


To find the best wool do a Google search on “merino wool roving”. Apparently wool “roving” is what folks use to make felt and stuff. It's astonishing what you learn in the pursuit of more efficient fly fishing.


I cut the tubing into 3 to 4mm lengths and slide it onto the needle. You can experiment with the amount of wool you need to make your ideal indicator.




I hope this works for you. Remember this information is given in good faith and is intended only for non commercial, personal use. It's given in the spirit of Rudi Ferris who willingly and freely shared his brilliant and original idea for this nymphing indicator with fly fishers everywhere!

Every serious river fly fisher should have one!