takedown project - pic heavy

[looseplucker]

OK - I know I was doing an osage bow, but I have been waiting for the sinew to arrive to back it - as a few cracks appeared on the back. No sinew yet and might use some linen thread instead and do it the same way as for sinew.

To while away the time - and also because I'll be in the US for the opening of their whitetail bow season and have been invited to a couple of properties I decided to see if I couldn't make up a takedown to go with me (cue roll of the eyes of the Leader of the Opposition and Baggage Supervisor).

Every component is largely from scratch. The sleeve and socket is made from 31mm diameter steel pipe from Bunnings. To make the inner socket I measured 2" along the pipe. I then made a cut down the pipe for a little over the 2" distance. I then went down the cut with an angle grinder. I then sawed the 2" length off. Why this way? Its a lot easier (and safer) cutting the kerf when the length is still attached to the rest of the pipe). Trial and error told me that one. Particularly the error.

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I then cut the 4" length which will be the outer sleeve. Did some tidying up with a file and then put a hose clamp around the 2" length (in the middle) and heated on a gas stove. Turned the screw and it sizes nicely - and you can test it as you go. Then applied some percussive engineering to flatten one side (which is the back) and used the vice to get the other end more rounded. This was all a bit fiddley - and the components do fit snugger now than in the photos.

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Some schools of thought suggest welding the kerf closed. I have not - and this is because as I thin out the socket part of the handle I can get the snuggest possible fit before applying the epoxy and glueing it all together.

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sleeve4.JPG (55.49 KiB) Viewed 2582 times

The bow itself is a core of spotted gum - 4x1.5mm lams. I plan to put bamboo on the back and the belly with the nodes internocking - this is the idea that Greybeard put up a couple of years back (and thanks Daryl for the continuous encouragement and ideas. The bamboo will taper 3mm down to 1mm and follow the width taper.

Currently the limbs are just under 1 1/2" wide at the fades, with that continuing a further 5" and then a width taper down to 5/8" at the tips. Tip overlay is red ironbark and those are going on the back before the bamboo.

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Riser section - due to the length of the bow, which is 59 1/2 ntn or thereabouts, you need as much working handle as you can get. The handle itself is 4" and there are 3" of fades either side - so 10". 11" would have been better but I actually had a moment of brain flatulence - but we'll work with what we have. I've glued the thing up progressively on a form I made. The ute makes a good hotbox.

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Riser itself is sydney bluegum and spotted gum.

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widthtaper.JPG (49.96 KiB) Viewed 2573 times

Any ideas/comments/suggestions would be gratefully received - this is my first attempt at a recurve (which I decided to do because of length restrictions) - so comments on dimensions etc would be very helpful.

I got a fair few ideas for the takedown assembly from TBB, the popular mechanics pdf "A Bow to Bring 'Em Down" which does plans for takedowns (even takedown longbows with a length of 54"!) and a great article sent to me by Daryl.

[longbow steve]

Pretty impressive LP, I think there are concerns with using the same materials in the sleeves but you will soon prove that wrong or right . Are you applying the bamboo later?
I dont know that you will get a great benefit from such a small ammount of recurve, perhaps you can pull it into further recurve when applying the bamboo?
Looking forward to seeing the results either way. Steve

[Stickbow Hunter]

It looks like things are going well mate and look forward to more photos as you progress. It will be interesting how the sleeve works; it better not end up a one piece.

Jeff

[looseplucker]

Howdy.

Steve - in terms of using the same materials in the sleeves I didn't quite understand the point - at this stage the core lams of spotted gum are glued up to the bluegum/spotted gum riser. The bamboo is yet to go on and then the sleeve and socket will be fitted. Should I have used something else?

In terms of recurve - theres 3" there - I will probably take it up a little more, but not much more. The last time I did one of these I went too far the other way, and the bow broke in spectacular fashion about midlimb during tillering so am being conservative.

The sleeve and socket should work - the idea of making them like this has been trialled before according to the literature, so we'll see how we go.

The other alternative is, depending on how the fitting goes, is to just use a 4" length of the steel and glue one end in and leave the other as just wood, per the article that Greybeard has spoken about in other posts.

At time of writing the second limb is out of the form and just about profiled with the first limb. Tip overlays of ironbark have been glued on and need some final shaping. Then the back lams of bamboo will go on and I will then fit the sleeve and socket. At that point I'll check the tiller and what have you and then fit the belly lams

[longbow steve]

Hi Lp, With regards to the sleeve, The commercially available are made from brass and steel, probably slightly different expansion rates in temperature variations and less likely to corode together if left in one piece.
Steve

[looseplucker]

Ahhh - OK - did wonder about that.

I still have some time up my sleeve (ha!) and have not checked out the local plumber's supply shop for brass, but plan to do so. If I find some brass that will either fit up my current steel tube or that I can adapt I'll probably go with that and start over.

Thanks for the clarification. I had a real 'doh' moment there.....now I see the point about 1 pieces....

[Crowcreek2]

Hi, not that I am an expert on bow building but one reason why stainless and brass are used as the sleave material's is to reduce the possibility of 'binding' which can happen with like alloys - basically the difference in alloy mechanical properties (hardness/coefficent of friction) helps with this regard.

Also carbon steel 'joints' that form a natural crevice will encourage corrsion far more?

Regards.

[greybeard]

I agree Crowcreek2,

3 Rivers offer the choice of steel/brass or stainless/brass sleeves.

The obvious solution to stop 'binding' is that when the days shooting is finished unstring the bow and take it apart.

Daryl.

[Glenn]

The bow looks as though it is coming along well LP. Will be keen to see how she shoots. I want to make a take down all wood bow next...Glenn...

[looseplucker]

Camera is again on the blink - will have some more pics soon.

But both limbs are just about ready to have the bamboo lams put on the back and the belly. Went over the cores with the digital caliper (what an invention - $20 at Jaycar) and there is a bit of sanding here and there with the width and thickness tapers.

Just off to a plumber's supplier to see about some brass.

[looseplucker]

Update time.

Got a hold of a 10" length of brass pipe from Metalmart scrap metal - 28.5mm outside diameter - my steel pipe has an inside diameter of a little more than that (about 29mm) so it should make a decent fit.

Also - speaking with Jeff this morning we talked about oxidisation and things and I recall one thing my Grandpa showed me with 2 piece fishing rods that often had a steel and brass ferrule (and could still stick) - get some of the skin grease from the side of your nose by running your fingers down it or through your hair and apply that - I would leave my surf rods together for days without a hassle.

Lanolin works just as good - I would also put a lubricant in there as a water barrier in case of bad weather.

And Daryl has the right idea - take it apart.

If however a rod ever did get stuck the remedy was to boil the kettle and pour water over the sleeve - it expands quick than the inner one and the thing will come apart easily.