Bow International

Making Your Own Barebow Riser

By Paul Meeson

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Itook up archery around 2010 after my young son had decided he wanted to buy himself a beginner type jelly-bow to shoot at home. I had shot air rifles & catapults when I was younger so archery seemed to make sense.

We shot together at UK NFAS shoots along with my daughter, after trying various styles along the way I eventually settled with the American Flatbow.

I shot this for quite a few years & enjoyed a fair bit of success until eventually in 2016 I decided to make the change to barebow, what I strove for was improved accuracy without fitting a sight. I felt I had got as far as I could with gap shooting the flatbow & natural progressio­n dictated that stringwalk­ing a barebow would be the next step.

The style I chose to try was WA barebow. I have always worked in engineerin­g, had always made my own bows up to this point and saw no reason not to carry on, plus I had the resources at home.

Mark 1

In 2017 I made my first riser.

The Mark One was a forward-braced riser which was made more as a test of my ability to manufactur­e than to design. I shot this bow for about a year & saw my scores gradually increase. The riser balanced perfectly & shot well enough, I had my bad days with it but overall felt it had been a success.

I have tried to show the steps required to turn a stock blank of 6082 T6 aluminium into the finished item. The manufactur­ing

of this first bow proved I had the ability & resources to produce whatever I wanted within the constraint­s of a manual 2D milling machine. It took six months to design, the manufactur­ing time for this first attempt was 64 hrs whichinclu­ded making any fixtures I needed & also a fair amount of head scratching.

After having made the Mark One I spent a while shooting an excellent secondhand German riser. I shot very well with it, but I am always happiest shooting bows I have made myself!

Mark TWO

The Mark Two took around a year of design time and 50 hours to manufactur­e. My design criteria was the same as any of the commercial manufactur­ers: to produce a riser which was steady on aim, reacted consistent­ly & absorbed as much of the limb energy as possible.

One of the challenges of shooting barebow for me is achieving a consistent bow reaction on loose. The weight is so closely fitted to the riser that its effect can sometimes be negligible or ambiguous, meaning that the bow can vary from rolling forwards or backwards or remaining vertical on loose & dropping away, this can also be the result of excessivel­y gripping the riser instead of shooting with no or very little grip.

"I WANTED TO ACHIEVE A BOW WITH WEIGHT POSITIONED SEVERELY ENOUGH TO GIVE THE SAME REACTION ON EVERY SHOT”

Personally I prefer the bow to either drop away vertically or roll forward slightly if possible.

The difficulty in tuning weight distributi­on under the constraint­s of WA barebow though is that everything must fit through the 122mm ring & no additional weight can be added to the upper portion of the riser. For the bow to roll forward to any degree then the weight has to really be concentrat­ed either above the grip or below the grip as far forward & as near to the vertical centre line of the riser as possible – whilst still remaining legal.

If you want the bow to remain vertical & drop away then the weight distributi­on needs to be nearer neutral. If you were able to hold the bow with an open hand & no weight on the string that it would sit vertically. The problem I have with this type of weight distributi­on is that because the weight is so unbiased that the bow could also roll backwards on loose – not ideal.

Tuning weight is not such a problem for an Olympic style riser as the many weight positions & weight lengths available allow near-unlimited tuning options. As a full set of recurve stabiliser­s can add a fair amount of weight to the bow the many weight reduction cut outs in the upper portion of the riser probably prevent the overall bow mass becoming too excessive.

However with a barebow set up I believe this is probably where material now needs to be left in to help with providing some bias to the bow & give a definite reaction instead of an ambiguous, unpredicta­ble one.

I saw the solution as to drasticall­y reshape the lower portion of the riser & push as much of the bow's weight as far forward as possible with the ability to include additional tuning weight as required. It may turn out to be necessary to include additional threaded inserts etc. to improve tuneabilit­y.

The idea with the Mark Two was to provide 30mm diameter holes in the front portion of the lower riser into which 30mm stainless steel bar could be fitted to allow further tuning to take place, and these could also be moved sideways if necessary to offset the asymmetric­al nature of the riser above the grip.

I wanted to achieve a bow with weight positioned severely enough to give the same reaction on every shot but not be so heavy that it wants to fall out of your hand when held at full draw with an open hand. The bow should be able to react naturally when loosed & anything that causes you to grip the bow is detrimenta­l to a good shot. The only way to satisfy both these requiremen­ts is to increase the weight's overturnin­g momentum by moving it away from the bow rather than just keep increasing its mass.

This riser was at this point the best I had ever shot. I found I was starting to hit the centre on shots where normally being close would have been good enough. However I was not happy with it from a design point of view. One of the elements of the design I struggled with the most (being an engineer, not an artist) is making the final design look considered & not just the result of an accident.

I had wanted a riser where the weight was projected forward & because I felt the riser was heavy enough without the added weights I ended up with empty holes in the front of the bow where I wanted weight to be, this was the opposite to what I had planned. A redesign was needed. Mark One had been donated to my good friend Gary Hart and the Mark Two was to join it. Gary was quickly becoming curator of my own personal barebow museum.

mark TWO includes 30mm holes to allow stainless steel bar to be inserted for tuning

Welcome to Mark THREE

The design change this time had been to remove as much material as possible from the bow to allow weight to be added in the right place without becoming excessive. I also removed counterbal­ance weight from the rear in order to increase the overturnin­g effect of front-mounted weights. This design change would mean that the riser could be as light or as heavy as I wanted and that the weight to the front of the riser would have as much effect as possible. The picture shows the bow without any additional weights fitted, I still have to make these and trial them but unfortunat­ely a problem with my lathe has delayed this for a short while.

I wanted the grip to be deeper than standard to make it more difficult. This would ensure that I would have to weight the bow perfectly for my draw weight – if I didn’t then it would drop out of my hand when on full draw with an open hand. This was only a modificati­on to the grip. not the riser. Standard grips can be fitted and Gary had started 3D printing these, allowing a whole new area of prototypes to be tested.

THE FUTURE - MARK Four

I have now been shooting the Mark Three bow for about six months but unfortunat­ely due to the pandemic not very often. Signs are good & thoughts have already turned to the Mark Four. If you look at the pics carefully you will notice that the ILF insert is fixed & not adjustable. Personally I prefer this, as I just see it as one less thing to fiddle with! An adjustable or fixed option may well be included in the design of a Mark Four.

For the Mark Three I decided to use a method commonly used by bowyers for making riser blanks for traditiona­l bows which uses a horizontal sanding machine & a 1:1 template which is fixed to the aluminium blank after it has been closely cut to shape on a bandsaw. This saved a lot of time, but is noisy and dirty.

The main piece of machinery I use is a manual vertical Bridgeport milling machine. The main constraint using a manual machine compared to a CNC (computer controlled machine)is the inability to easily cut large radii, severely limiting the design of the outer profile. Having CNC machining capability allows more complex shapes to be made, and I have started converting mine from a manual to CNC.

I see my future in riser design as simply enjoying the process of research & developmen­t. If I get enquires for risers or not the future is still great, either way I will be enjoying what I enjoy the most: making stuff.

Mark Four will be hopefully a more exotic CNC machined riser incorporat­ing every change I have made so far. Some of it will be right, some wrong, but the only way I will know is to try!

 ??  ?? The Mark THREE, practicall­y
The Mark THREE, practicall­y
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 ??  ?? A deeper grip equals a more difficult grip
A deeper grip equals a more difficult grip
 ??  ?? the mark 3: finished, but unpainted
the mark 3: finished, but unpainted
 ??  ?? sanding to shape using a 1:1 Template fixed to the blank
sanding to shape using a 1:1 Template fixed to the blank
 ??  ?? bridgeport milling machine
bridgeport milling machine

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