Making a rope and pulley tiller board

This blog is meant to serve as a quick how to for any budding bowyers or anyone who has made plenty of bows but always tillered on a fixed notch tillering stick.

The idea here is not a new one and was first brought to our attention several years ago on one of our Bow Making Weekend courses by guest instructor Gary Scott of Christendom Bows. To me this way of tillering a bow is far more sympathetic to the bow as ordinarily you would stretch the bow to a certain draw length and hook the bow string into a notch on the static tillering board before standing back to scratch your head and ‘um’ and ‘errr’ appreciatively for several minutes whilst you figure out which bits are bending and which bits are still way too stiff.

If you think about it leaving a bow drawn on a tiller board is a completely unnatural position for the bow to remain in. It stands to reason that the timber in the bow you are shooting is under the greatest forces of compression and tension at its full draw. Therefore, KEEPING it under those tensions for longer than the fraction of a second it takes to release the arrow is not a good thing for the general health and well-being of the bow.

This is where the rope and pulley tiller system plays its part as you can gently draw and release the bow progressively drawing it further down the board whilst already standing in a position that allows you to assess how the bow limbs are bending.

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Here Woodland Ways Instructor Danny assesses a stiff section through the left limb of an Elm long bow.

Someone once explained this process to me as being similar to touching your toes – if someone came up behind you and pushed you down suddenly and quickly you would pull all the muscles and tendons in your legs. Rather what you want is a gentle progression of reaching a tiny bit further on each gentle stretch, returning to a relaxed standing position after each attempt.

So it is for bows! Remember this branch you are working has been a static straight thing sometimes for many decades and to suddenly force it into a bend AND keep it there is just like that person forcing you to touch your toes without any warm up. Ouch.

Toe touching analogies aside, the rope and pulley tiller is a fairly straight forwards DIY project and only requires a couple of items you may not already have laying around in the shed.

The following diagram accompanies the photos to give you an overview of how the various components fit together in this tillering system:

rope and pulley tiller diagram

Step 1

Secure a block of wood onto a plank of wood. Dimensions are not that important except that the long plank making the main section of this tiller must be at least 40’’ in length to allow for a tall persons’ maximum draw length plus enough space for the pulley to be attached at the bottom. The block of wood used here was roughly 6’’ long

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This 6’’ block of wood will potentially be supporting anywhere between 25 and 85lb’s of downwards pressure from a bow as it is tillered so make sure it is attached with at least 3 good screws rather than nails.

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Step 2

Next we need to form the ‘U’ shaped recess at the top of the tiller where the bow handle will be located. This is achieved simply by securing a short section of plank (matching the long back section) on top of the 6” block. Again secure this short piece with at least 3 screws.

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Notice how this short piece of plank overlaps the 6” block by the same amount the long back section overlaps it – this forms the recess where your bow handle will be located. Again the exact measurements are not important here so long as the recess is deep enough to prevent the bow pulling off the tiller board in use – it was roughly 3” deep in this example.

Step 3

The long back section now needs to be turned into a form of measuring stick by marking every couple of inches down from the top of the short 6” block of wood. As the short block of wood obscures the first 6” the first measurement marked here was 8” and then every 2” thereafter up to 32” at the bottom end of the long section (see diagram above).

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Step 5

There are many ways of fabricating the next part of this project but these were the items I had on hand; one item here is important and that is the pulley. These can be picked up inexpensively at Homebase or B&Q.

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Photo shows pulley, coat hook and a hose clamp left to right.

Drill two small holes at the bottom of the main tiller board and open up the dog clamp before threading it through these two holes. Attach the pulley onto this hose clamp on the front of the tiller board.

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Additionally you will need to attach another short block of wood right at the bottom of the tiller board beneath the pulley. This is so you can drill a hole through and thread a length of rope to attach the whole system vertically to a tree (see above photo).

Repeat this at the top end of the tiller board by drilling a hole through the 6” block of wood – again a length of rope will be fed through here.

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Step 6

Now we are going to create a hook which we can loop over the bow string and then pull down through the pulley via a length of rope – see diagram of pulley in use.

Take the coat hook and screw it into the end of a short section of wood (pre drilling a pilot hole will prevent this from splitting).

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With the block of wood secured to the coat hook you can now attach the rope you are going to use by any means available. Here I used a heavy duty staple gun and black electric tape.

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Step 6

Okay time to set up your new tiller board!

Thread the opposite end of rope from the hook through the pulley and make sure you have at least 6’ of rope to allow you to stand back away from the tiller board whilst it is being used – this helps you take in the entire profile of the bow at a glance.

Find a suitable tree and after threading two lengths of rope through the two holes you drilled attach the tiller vertically to the trunk of the tree.

Taking the bow you are working on place it into the recess at the top of the tiller board with the exact centre of the handle contacting the centre of the recess.

Pull the bow string down and hook it underneath the 6” block of wood before taking the coat hook and attaching it to the centre of your bow string.

Now take up the end of the 6’ rope and standing back start to pull down on the rope taking up the slack through the pulley until the rope comes tight.

Now as you pull the rope you will pull your bow string down towards the pulley causing the bow limbs to bend as they would in normal use. Standing back from this you are now able to assess  how one limb is bending in comparison with the other and by identifying stiff or weak spots make corrections until your bow is bending evenly or is ‘in tiller’.

Remember to only hold the bow at draw momentarily before releasing the rope and allowing the bow to relax before pulling it down again. As you work through the tillering process you will be able to draw the bow further down the board until you reach your own personal draw length.

Further improvements…

  • You may find it useful to have a G clamp on hand to secure your bow into the recess whilst using this type of tiller.
  • The recess can be padded with soft leather to protect your bow handle from damage once you are in the finishing stages of the bow.
  • A short wooden handle can be added to the end of the 6’ rope so that you don’t have to pull down 95lb’s of pressure through a rope wrapped round your hand!

Perhaps most usefully the addition of a fish scale to the end of your rope will tell you the poundage (weight) of your bow at a given draw length by noting how far down the back board you have pulled your bow string and at the same time reading off the measurement on the fish scales. You can achieve the same using a fixed notch tiller board on top of a set of bathroom scales.

I hope this is a useful addition to your bow making tool kit. Share your creations and tillering ideas on our Facebook group or get in touch with any bow making questions you may have. The Woodland Ways bow making weekends are gaining in popularity and we still have a few spaces on this year’s course dates. We hope to see you in the woods soon!

Adam Logan,

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