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Posted: Tue Jun 28, 2011 5:51 am
by jackssmirkingrevenge
Alster370 wrote:Would drilling holes or making cuts at the centre allow it to bend more easily?
I would think a central groove or slit from end to end of the prod would be much better, in that it would not create specific weakpoints as holes or cuts would and spread the flex.

Posted: Tue Jun 28, 2011 5:52 am
by jackssmirkingrevenge
:oops: ImageImage :oops:

Posted: Tue Jun 28, 2011 6:08 am
by inonickname
jackssmirkingrevenge wrote:
Alster370 wrote:Would drilling holes or making cuts at the centre allow it to bend more easily?
I would think a central groove or slit from end to end of the prod would be much better, in that it would not create specific weakpoints as holes or cuts would and spread the flex.
Yeah, drilling holes a huge invitation for very violent failure. How well does a balloon work if you poke a hole in it? Those leaf springs are under lots of stress.

There's other cocking method available. Have a look. A cocking rope could even help. A goats foot lever would also be effective. Have a look at the swiss twinbow as well. 300 pounds of draw weight, but it's one of the easiest, smoothest, and quickiest cycling crossbows.

Posted: Tue Jun 28, 2011 6:26 am
by Crna Legija
Alster370 wrote:My current setup is a leafspring, but its a bit too resistant for hand cocking and i dont want to have to use a winch. So i though about ways to reduce its resistance to bending so I can cock it with less force. Would drilling holes or making cuts at the centre allow it to bend more easily?
maybe you could heat it up a bit more to take some of the springiness out of the steel, Thats if it can fit in your oven.

Posted: Tue Jun 28, 2011 7:31 am
by inonickname
Crna Legija wrote:
Alster370 wrote:My current setup is a leafspring, but its a bit too resistant for hand cocking and i dont want to have to use a winch. So i though about ways to reduce its resistance to bending so I can cock it with less force. Would drilling holes or making cuts at the centre allow it to bend more easily?
maybe you could heat it up a bit more to take some of the springiness out of the steel, Thats if it can fit in your oven.
Then the steel stops being springy :wink: leaf springs are quite finely tempered- tempering them certainly won't add benefits in this regard.

Best option is to set up a cocking lever like the goat's foot, or carefully grind the spring to reduce the width, and thus the stiffness.

Posted: Tue Jun 28, 2011 4:11 pm
by Heimo
inonickname wrote:or carefully grind the spring to reduce the width, and thus the stiffness.
that is probably the best option, also if you are going to go this route, remember to cool it regularly while removing material to prevent the heat from affecting the temper

Posted: Sat Jul 16, 2011 5:02 am
by Alster370
Id have to rule it out since I don't have a bench grinder yet. :oops:
Also they tend to be rather heavy, and im going for a lightweight design. One object I notice has alot of bend and resistance, is the shaft on golf clubs( junior ones more often) I believe it is graphite/steel?

Posted: Sat Jul 16, 2011 5:14 am
by Crna Legija
Alster370 wrote:Id have to rule it out since I don't have a bench grinder yet. :oops:
Also they tend to be rather heavy, and im going for a lightweight design. One object I notice has alot of bend and resistance, is the shaft on golf clubs( junior ones more often) I believe it is graphite/steel?
then make a slingshot rifle.

Posted: Sat Jul 16, 2011 5:18 am
by Alster370
I have one in the drawing stages actually, il start work on it after I come back off holiday, as well as my upcoming coax.