Troublesome Spruce

[JoeLethbridge]

Hello everyone,
recently I bought sitka spruce shafts from (Amso128), who ordered them from 3rivers, who probably sourced them from Hildebrand in Alaska.
The first time I ordered 60 5/16" shafts with a 40-45 spine for my 40# Norseman longbow w/a dynaflite string. These shafts were too light for the bow by far! What was wrong? The shafts felt too 'whippy' compared to the 'Lucky' Bunnings dowels. Was it the dynaflite string? Apparently they add a few fps to the bow cast. Anyway I ordered 30 a few weeks later, 11/32, 45-50. 6 of these were hand barreled with sandpaper, as I only have a 5/16 taper tool, nocks and points. They were cut to 30, and roughly bare shaft tuned and sealed, fletched, nocked and tipped. It turned out that the spine of the shafts were still too light, so I shortened them to 28.5". Now, the spine of the 6 varies from far too light, to almost too stiff! Is it something to do with the tapering process?

Please Help, Joe

[perry]

Hello everyone,
recently I bought sitka spruce shafts from (Amso128), who ordered them from 3rivers, who probably sourced them from Hildebrand in Alaska.
The first time I ordered 60 5/16" shafts with a 40-45 spine for my 40# Norseman longbow w/a dynaflite string. These shafts were too light for the bow by far! What was wrong? The shafts felt too 'whippy' compared to the 'Lucky' Bunnings dowels. Was it the dynaflite string? Apparently they add a few fps to the bow cast. Anyway I ordered 30 a few weeks later, 11/32, 45-50. 6 of these were hand barreled with sandpaper, as I only have a 5/16 taper tool, nocks and points. They were cut to 30, and roughly bare shaft tuned and sealed, fletched, nocked and tipped. It turned out that the spine of the shafts were still too light, so I shortened them to 28.5". Now, the spine of the 6 varies from far too light, to almost too stiff! Is it something to do with the tapering process?

Please Help, Joe

I would have started with 55-60# Spine Shafts and 160 gr Points, then carefully tapered the Nock end / bareshaft tuned until you arrived at the correct Spine. I'd guess something around 52# with 160 gr Points. Advantage of Heavier Points is better Forward of Centre and more closely matches common Broadhead Weights. You can also switch to lighter 145 or 125 gr Points if you wish to further adjust Spine etc, just Taper the Shaft to match Spine with the lighter Points if they where correct with the 160 grainers

By tapering your 45-50# Spine Arrows you have reduced the Spine. Also sounds like you have removed timber unevenly or the Shaft where not matched in Spine to start with.

String Material is important, the lighter and less stretch the String the more energy is put into the Arrow, stiffer Spine required. I fine tune all my Bows by using different Weight Arrows and number of Strands in the String so they have a common Point Blank Range. Try more strands in the String if Arrows are only just underspined.

I really like Sitka Spruce Shafts, very Strong and recovers from Paradox quickly.

regards Jacko

[greybeard]

Joe, here is a link to an earlier posting, it may help.

http://www.ozbow.net/phpBB3/viewtopic.php?f=3&t=845

Daryl.

[Mick Smith]

So, what's your draw length? If it's longer than 28 inches, you will need to make allowances when selecting your shafts. Your bow will also have a higher draw weight than 40# if you have a draw length of more than 28 inches, as non custom bows are always measured @ 28 inches. This will also have to be taken into consideration.

You mentioned that you cut some shafts to 30 inches, so I'll use this draw length as a rough guide. If your bow has a draw weight of 40# @ 28 inches, it will have a draw weight of around 46# @ 30 inches of draw length. You can't just go and buy shafts spined for 46# because they've been spined for a draw length of 28 inches, not 30 inches. You would need to go heavier in spine to allow for the extra length. At a guess, you would need to go up in spine 5# for each inch over 28 inches. This means you would probably need 55-60# spined shafts, if indeed you do have a 30 inch draw length.

You can't buy 5/16 inch shafts in anything over 50# spine in my experience, so it might be easier to buy yourself some new 11/32 inch tools. Of course you can taper the back of your shafts back to 5/16 if you want, but that means you would have to take the consequentially reduced spine of your shafts into consideration by doing so.

[JoeLethbridge]

Hi guys, Right now I'm using 100gn 5/16" field points on these arrows.

Mick, my draw length is 28.5, so I'd probably be drawing 41.5#. I just cut the arrows to that length to see how they would shoot bare-shafted. I later cut to 28.5".

Jacko, as for the string, I might just make a b-50 string for that bow.

Would there be a way to heat-treat these shafts to harden and stiffen them? I believe this has been done with bamboo arrow shafts in the past? If it works with wooden bow limbs (Marc StLouis style), why wouldn't it work with arrows?

I probably will end up buying 11/32 nocks, points and tapering tool.

Thankyou for the advice so far, Joe.

[Mick Smith]

You could increase the dynamic spine of your arrows by to replacing your 100 grain points with some 70 grain points. Hopefully, they would still fly reasonably well.

[perry]

Don't try to heat treat the Shafts they are what they are, Heat will destroy them

Sounds to me like your flogging a dead horse with those Shafts, cant see how going to 70 gr Points will help

Where do you live Joel, we might be able to put you onto someone who can give Face to Face instruction with making Arrows. There is so much info out there sometimes it better to have someone help you sort the wheat from the chaff. I'd be really surprised if you spoke to Nick Lintern John McDonald or any other reputable Traditional Archery Retailer and they could not recommend to you the Spine Shafts you need. Always best to start overspined and reduce Spine. I have often used 000 Steel Wool to Taper the rear half of a Shaft to reduce Spine a tiny bit at a time when Bare Shaft Tuning. Once you have arrived at the correct Spine put a sample Shaft aside, buy or make a Spine Jig and make all your Shafts to match it.

Reading between the lines I am wondering if you have fallen for the Trap of trying to make your Bow shoot fast and flat by cutting it very fine with Arrow Mass and a light Bow String, Speed comes at a Price. PLease go for stability and Accuracy, some 400- 450 grain Arrows from your 40# Norseman and Matched Arrows and you will have a very sweet and Accurate Outfit

Switching to a heavier Dacron String is fine but be aware the Bow will be noisier and develop Handshock because the String Stretches. It will also be slower. I don't think it will help with your Arrows

I reckon this link explains Spining Arrows pretty well http://www.alaskabowhunting.com/Matchin ... s-W16.aspx

regards Jacko

[Mick Smith]

Have you actually shot the shafts that you think are too 'whippy'. They may be whippy in comparison to the Bunnings dowels you bought, but that might not necessarily mean they're under spined.

Those shafts should be okay for your bow at your draw length of 28.5 inches. You may not have a problem at all. How do they shoot? Are they erratic in flight?

If it becomes necessary, you could put lighter points on the shafts as I mentioned in my previous post. This would have the effect of slightly increasing the dynamic spine of the shafts. A 30 grain decrease in point weight would most certainly have some effect on the dynamic spine of the shafts. The big drawback with arrows fitted with light weight points and a poor FOC weight distribution, is that they usually perform in a disappointing manner. They might be fast, but they will be very 'twitchy' making them difficult to shoot with any real consistency, but still it might be better than using all of your new shafts for firewood.

[JoeLethbridge]

Thanks guys!

[Ian Turner]

Hi Mate,
I really like the spruce shafts from John; i find they are tough and good consistant spine; only a few pounds between them.
My 40lb recurve likes the 50-55lb 5/16 and 11/32 shafts with 100gr points and my 40lb LB likes 50lb+ 5/16 with 100gr points.
if i go below 50# in shaft spine then i use 70gr points.
My arrows still fly well with the 70gr's.
Cheers
IAN

[Mick Smith]

Hi Ian.

Just out of curiosity, what's your draw length?