Published Feb 19. 2014 - 9 years ago
Updated or edited May 15. 2016

Welding your loops

A simple 7-step guide will show you how to make small, neat loops on your fly lines. Just like the pros - just neater. Now you can finally say goodbye to big clumsy loops, acetone, glue and sewing processes. Doing it this way will give you, small, smooth and round loops.

Practice on an old fly line or a cheap line. The first few times you might fail, but when you get the hang of it, its quit easy.

This is only a start-guide. There are many variants of making loops with shrink tubes. Make your own experiments.

Part 1: Standard loops

Below is a step-by-step guides showing how to make welded loops. The method is universal for all coated fly lines and gives strong, small and neat loops, which will glide noiseless through the guides.

Step 1 to 7 is necessary for all.

Step 1

- Insert your fly line into a piece of shrink tube af approx. 6-8 cm (2-3 inches).

Michael Sørensen

Step 2

- Form a loop on your fly line.

Michael Sørensen

Step 3

- Insert the tip of the fly line into the shrink tube.

Michael Sørensen

Step 4

- Stop the tip approx. 1-2 cm (1/2 inch) from the edge of the shrink tube. This is important to make sure you don't hit the fly line when heating.

Michael Sørensen

Step 5

- Carefully Apply heat to the shrink tube. Use a lighter og a candle. Apply the heat i short intervals. The coating of the fly line will melt and merge. Repeat this until all the fly line connection is smoothly merged. Don't apply too much heat.

Michael Sørensen

Step 6

- Wait for the coating of the fly line to cool a bit down. Then you can remove the used shrink tube carefully. The shrink tube is best removed while it is still a little warm.

Michael Sørensen

Step 7

- Congratulation - You have completed your first loop

Michael Sørensen

Part 2: Tune your loops
The following step-by-step focuses on thicker fly lines.

Step 8

- Apply a little heat to your loop (only a few seconds to not damage the core).

Michael Sørensen

Step 9

- Remove the warm coating from the core.

Michael Sørensen

Step 10

- put the loop inside a piece of shrink tube.

Michael Sørensen

Step 11

- Stop 2-3 cm (1 inch) from the edge og the shrink tubes.

Michael Sørensen

Step 12

- Heat the coating in the point where it turns into loop. Be careful, not to apply too much heat to the core. It is very sensitive to heat.

Michael Sørensen

Step 13

- While the coating is still hot, pull carefully in the shrink tube. Pull approx 0,5 cm (1/4 inch) this will smooth the transition to the loop.

Michael Sørensen

Step 14

- Keep the shrink tube in the pulled position until you are sure the coating is no longer liquid.

Michael Sørensen

Step 15

- Remove the shrink tube.

Michael Sørensen

Tip 1:
Always carry a lighter, a sharp pair of scissors, a small piece of shrink foil and a lighter with you. With this first aid line kit you can repair the lines, if the loops for some reason breaks.
These loops are not as strong as the real welded loops, but it is great that you can repair a line at the bank.

Tip 2:
Practice on old worn out fly lines before making loops on the ones you are going to use.

Tip 3:
Start making loops on floating lines. Due to the materials, they are much easier to weld than sinking lines.

Tip 4:
The weakest point is where the point of the loop is welded into the line. The durability will be heightened if you make a cut, tapering the line before welding.

Tip 5:
You can color code your lines by adding a small piece of coating in a different color under the shrink foil before welding. It requires some practice but the result is overwhelming.
Of course you can mark the line with markers before welding. However, this will fade over time.

Step 16

- You now have a really nice loop on your fly line ;-) It works even better if you reduce the thickness by removing some of the coating on the fly line, at the point where it is merged, before step 1.

Michael Sørensen
This guide is made by Michael Sorensen from Innosoft, check out his fish condition calculator app here.


Some tips on schrink...

Some tips on schrink tubes:
Size of schrink tubes depend on your flyline size. Make sure that it schrinks into a thinner diameter, than your fly line.
For example, if you have a 1.1 mm fly line (at the loop point), the schrink tube should schrink to approx. 0.8-1.0 mm. A 3.0 mm, 3X (schrinks into 1/3) schrink tube, will schrinks into 1.0 mm. A 2.0 mm, 2X (Schrinks into 1/2) will schrink into 1.0 mm as well. Both sizes works.
Some schrink tubes varies a bit before schrinking. a 3.0 mm can vary +/- 0.5 mm. This doesnt matter much. It normally schrinks into the right diameter anyway.

When you buy schrink tubes, make sure to pick the transparant ones. You have to watch through the schrink tube, to see if it is welding.

When applying heat, be very carefull not to overheat it. It will break the core. Apply heat for a few seconds. then wait and watch for a few seconds. It it welding together? If not, the repeat and repeat. Until it is welded correctly. The heat is a little delayed, so don't heat constantly until it starts welding. It will most likely be too much heat for the core.

When you have the hang of it, make your own experiences. There are many ways to get a nice result.

Find transparant schrink tubes on ebay, seraching for "Shrink tube, Transparent, for fly line loop welding "

Martin Joergensen's picture

Graham, No... we ...


No... we can't send anything. We're not a shop.

You need shrink tube, a lighter and a pair of scissors. Look on eBay or Amazon or this UK dealer or your local electronics dealer for the tube - which should be just slightly thicker than your fly line - and in your supermarket for the lighter and the scissors.

That's the best we can do.


is there anyway you ...

is there anyway you could send me the tools and shrink rap to make my own loops please

you will find These...

you will find These tubes in any DIY Store in Germany-assorted in different length, colours and diameter. I use them to smoothen the different lines on my flyrole. Differently to this way I use to add super glue in the tube and shrink it then with hot air from a special heater. But I will try this way as well to see how it works.

Look for at a home s...

Look for at a home supply store like Home Depot, Lowe's, etc.

Very interesting. W...

Very interesting. Where do you buy shrink tubing? If it comes in various sizes, what size is best for a fly line?

Clear heat shrink tubing...

You can use a lighter to shrink down the clear heat shrink or just use boiling water

Anna's picture

Clear heatshrink...

You can use a lighter to shrink down the clear heat shrink or just use boiling water. Smallest size is 1.2mm shrinks down to 0.6mm all the way up to 6 inches (150mm)

Our clear heat schrink can be shrunk using a lighter or even in boiling water, not a lot of people know this. If you looking for other types, please send us an email to consider.

Anna's picture

Clear or Transparent Heat shrink tubing...

To heatshrink down clear or transparent heat shrink, if you have no lighters use "Boiling Water" as our Clear heat shrinks operate at boiling point which is 100C at when there locate search box and type in '2:1 clear heat shrink', we have the 1.6mm and a 2.4mm in Clear in stock.

Our clear heat schrink can be shrunk using a lighter or even in boiling water, not a lot of people know this. If you looking for other types, please send us an email to consider.

heat shrink...

Excellent tip. I would suggest experimenting with 3 to 1 adhesive shrink tube in either 3mm or 4.8mm. It shrinks 3 times its diameter and the adhesive melts and bonds the tube to the fly line. The heat will also weld the fly line together so double secutity. Smooth adhesive that leaks out of each end to create a slick feel to the tube ends. No need to remove the shrink tube afterwards. Can be color coded as well. I use black for reel end and red for the tip which also acts as an indicator. On e-bay 500mm of 3mm costs £1.95

Anna's picture

New reply...

The Adhesive lined stick or reeled 3/1mm needs a heat source for it to shrink down, keep applying the heat and the inner glue lining starts to melt and flow and ooze outwards, when this happens stop heating and allow to cool on its own. This will give you an incredible water resistant mould onto what you require.

Our clear heat schrink can be shrunk using a lighter or even in boiling water, not a lot of people know this. If you looking for other types, please send us an email to consider.

Missing the point...

You can not do Rais in boiling water. Yes the heat shrink tubing may shrink, but the soul purpose is to MELT the outter plastic coating of the fly line.


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