Sunday 18 January 2015

Bow Vibration Update (Part 4)

So, having bought my new riser and putting in the weakest spring on the plunger button, I tested it out in the garden. The arrows were still going left but were moving closer to the target. The bow string has not been adjusted but the brace height was 20.5 cm straight out the tube - this is the lowest recommended brace height, but no vibration. My partner removed the arrow points which were 80 grams and replaced with 100's. I twisted the string and upped it to 21, vibration is back again. String off again and untwisted, no vibration. Started doing a few test shots and the arrows are now hitting in the centre of the target. I moved the clicker out slightly, my button is on the weakest setting and my groups although not really tight are okay so I've left it there.

First Portsmouth shot. Results and first time shooting with this bow, 493. My highest last year was 519, so not too bad. When I'm sloppy they go left when I overdraw they go right, so I think it's now a case of practising my form and getting used to the way the bow behaves. I find that I get the best results if I hold my bow arm straight out and pull with my right hand rather than push/pull action.

So basically, I've learnt that the Arrow Easton Chart for ACC's are more on the stiffer side (for me anyway) but as I get used to this weight and eventually max out the limbs, they should be okay and that increasing the brace height might have had something to do with the vibration on my old riser. This is an experiment for another day on my older 23" riser.

And, just another thing if you know what riser you really want don't, buy online! Bowsports charged me £195 in-store for this riser - on-line the bow is £150. I didn't have my bow on me so no setting up or anything, what a rip-off.

Sorry this has been a text heavy thread, hopefully my next post will be a bit more colourful.

Thursday 15 January 2015

Bow Vibration Problems (Blog Part 3)

What a weekend. Tried to tune up my bow last Saturday, increased the brace height in increments and ended up at maximum with the help of Jenny at Beacon Archers (still bow vibration) and did some bareshaft tuning at 20 yards, to see where my arrows would go - way, way left - in fact they went into the next target. Adjusted the plunger button to the weakest it would go and managed to get the bareshafts onto the same target, but they are still shooting left. I thought a bit more research was in order and found that if I put in some heavier arrow points in this should weaken the arrow a bit, I haven't done this yet as I thought I was on the weakest spring on my plunger button, but as it happens it's fitted with the medium spring. Anyway, had Bob at Beacon archers look at my limb alignment and it was slightly off. Funny that, the chap at Merlin said my riser wasn't very good. There is no way for me to adjust limb alignment on the 23" Hoyt Elite riser. This could account for the Bow Vibration problems, so I'm still not really happy with my set up. Missed the Frostbite as I wanted to continue tuning up my bow, but I'm still no further forward.

Things have changed a bit since last weekend:

email to my club

So, I've got a new riser! Only problem now is that the poundage will be 30lbs on this one unless I adjust the tiller, but I'm leaving it as it is for now as it feels more or less the same. I'll test my pulling weight when I start shooting. I haven't touched the limb alignment as it looks okay and hopefully I've set up the centre shot correctly. Just need to see where the arrows go now for some further tuning. I've still got the weaker spring in the plunger to put in if needed and those heavier arrow points. I would imagine I'll end up changing both but we'll see. Hope it's not too slow.


Friday 9 January 2015

New Limbs, New Stabiliser, Tiller Adjustment and Still Bow Vibration

This is really a continuation of my last post, where I've messed up my bow by adjusting tiller, or so I thought.

So I went to Merlins and tried some 28lb limbs which is 30lb on my bow and shot a few arrows. The guy there was really, really helpful and adjusted my tiller and checked alignment etc for a few ££'s. But, I found this really to be the same strength as before on my SF Elite Fibre Foam limbs so I upped it to 30lb making 32lb on my 23" riser with some SF Elite Carbon Foam limbs. Much, much better. What a difference and I can pull back properly without changing the clicker. The guy said that there wasn't much play in tiller adjustment so that's probably why I was having trouble with the 32lb limbs, 34lb on my bow. So all set - apart from the recurve wobble after each shot. A decent stabiliser (around £65.00) was bought and this has helped but still there is wobble, so the problem is still there.

The frostbite was cancelled (it was just an unplanned one), which is good in a way as I still wasn't happy and was having to use my old arrows. Yesterday, I went to Bowsports which is way nearer than Merlin for me and got measured up properly for some new ACC arrows (I've been using Eclipse). I was going to order these on-line having looked at the Easton Arrow Chart but wasn't sure what poundage I was actually pulling. I thought I was pulling around 30lb as most limbs are based on 28" and my arrows were 27" (2 lb off for every inch lost, or on for every 2 lb over). So this was pretty borderline between group T2 (24-29lbs) and T3 (30-35lbs). I was going to go for the T3 group 3L-04's as I'm aiming for 32lb so that I can reach the 70 yards without having to turn my sight upside down and once I got used to my limbs I'm pretty sure I will be, but thought if I was wrong this is a pretty expensive mistake. So Bowsports measured me up. My actual draw is 26.5 but my pulling weight is 32lb as I overdraw - I draw back to just under my chin but use the corner of my mouth as my natural anchor. Good news for me as I've reached my target poundage. I now have 27" arrows and was told to put my clicker back as it should be in line with the riser, mine is about an inch out although I don't use this religiously.

Easton ACC's
Now for the interesting part about the Bow wobble. This isn't a little vibration, the limbs violently wobble about for about 2-3 seconds after each shot. I've been reading on the internet and this article was quite helpful. Most people seem to think that it's the brace height, arrows, string or tiller.  I'm ruling out the tiller as this has been set up and checked by Merlin. I set up the brace height during tuning quite some time ago, and this still remains the same but could have possibly changed, as I have increased my bow weight. However, I am hoping it is the arrows so I'm not going to change anything until I've tested these out, hopefully later today or tomorrow. I'll let you know, but for now I need to make up my arrows. I usually buy bare shafts and do the rest myself (saves a few ££'s and I enjoy it). Fingers crossed it's the arrows and I can go straight onto bareshaft tuning.

Saturday 3 January 2015

New Limbs, Tiller Tuning and Messing Up my Bow!

Well, what can I say.  I bought some new limbs thinking that I could adjust the tiller to lower the poundage and all I've done is messed up my bow.

I have a 23" riser with 26lb limbs which makes them 28lb, the tiller has been adjusted to push them up to 30lb and I have been shooting fine with them and because I feel no strain or difficulty I decided to buy new limbs so that I could go up a couple of pounds. My reasoning is that I should be able to adequately reach longer distances without having to turn my sight upside down. So I bought 32lb limbs (which makes them 34lb) thinking I could adjust the tiller to bring the weight down to 32lb. In theory, this should have worked but in practise it was really hard for me to pull back. I had to adjust my clicker right out from the bow as I couldn't draw back the same amount as before. My long rod then kept loosening itself, so I bought a new one (slightly shorter) and I re-tuned my bow. After shooting a 'frostbite' with this set up and not getting very good results, I decided to put my old limbs back on. Adjusted the tiller back to where it was and then I shot a Portsmouth with a very wobbly bow. The vibration was really, really noticeable as the bow was shaking and vibrating after each shot. So the tiller got adjusted again until it wasn't too bad. Shot a couple more sessions with it and then just before Christmas it went back to being wobbly.

We now have a 'Frostbite' tomorrow.  So …. I've been on the Internet looking at tiller adjustments and I found a really great PDF by Medway Archers. After reading this I'm actually thinking of buying some new limbs 28lb's which would make them 30 and then screwing the tiller right in to increase the weight to 32lb. I still have my new limbs to progress into - right :). The one thing about the PDF that I liked was how I didn't know that some limbs were already made with a heavier bottom limb so this needs to be checked first! I'm going to screw the tiller bolt all the way in and then check if the top and bottom measurements are the same and work from there. I hope it doesn't rain today as I'm going to have to paper tune again - before tomorrow.

Anyway, let's see if the shops are open!

ps another couple of great tuning guides

This is a great guide for beginners Bowmen of Overdale
Conversation about tiller adjustment
and of course the FITA Coach Manual