Cross Bow II - Revision history

Adamcolton at 15:02, 23 August 2018

2018-08-23T15:02:56Z

← Older revision		Revision as of 15:02, 23 August 2018
Line 16:		Line 16:
	The knock is a small piece glued on the end so the string doesn't split the bolt along the split cut for the fins. This is where I want to get a little more complex. The previous knock design was simply a groove for the string. This time I want to drill a small hole 1/4 from the back end of the knock. Cut a small opening from the back to the hole, with tapered sides. The objective is that the tapered edges will guide the string into the hole but once it's in, the opening will be small enough to prevent the bolt from falling off easily but still allow a smooth release when firing.		The knock is a small piece glued on the end so the string doesn't split the bolt along the split cut for the fins. This is where I want to get a little more complex. The previous knock design was simply a groove for the string. This time I want to drill a small hole 1/4 from the back end of the knock. Cut a small opening from the back to the hole, with tapered sides. The objective is that the tapered edges will guide the string into the hole but once it's in, the opening will be small enough to prevent the bolt from falling off easily but still allow a smooth release when firing.

	~~[[Category:Projects]]~~
	[[Category:Workshop]]		[[Category:Workshop]]

Adamcolton at 18:27, 6 June 2013

2013-06-06T18:27:16Z

← Older revision		Revision as of 18:27, 6 June 2013
Line 1:		Line 1:
	=Description=		http://www.instructables.com/id/Pump-Action-Hex-Nut-Slingshot-Rifle/

			== Description ==
	Diverging from the "classic" crossbow, I want to use a pulley as the force multiplier (or in this case, reducer). The main mechanism is 2 parallel bars, the front fixed and the back slides, attached to the spring. the drawstring is wrapped around the bars a few times (with force = 90lbs/wrappings and distance = 3in*wrappings). I suggest 4 wrappings, this gives a pull force of 22.5 lbs and draw distance of 12", making it suitable for a handgun design.		Diverging from the "classic" crossbow, I want to use a pulley as the force multiplier (or in this case, reducer). The main mechanism is 2 parallel bars, the front fixed and the back slides, attached to the spring. the drawstring is wrapped around the bars a few times (with force = 90lbs/wrappings and distance = 3in*wrappings). I suggest 4 wrappings, this gives a pull force of 22.5 lbs and draw distance of 12", making it suitable for a handgun design.

	=Trigger=		== Trigger ==
	I plan on using a similar trigger mechanism as in [[Cross Bow I]] but instead of a single string catch, I want two smaller catches spaced wide enough apart that I can knock a bolt between them.		I plan on using a similar trigger mechanism as in [[Cross Bow I]] but instead of a single string catch, I want two smaller catches spaced wide enough apart that I can knock a bolt between them.

	Alternatively, the trigger could be connected to the moving pulley bar, which gives some flexibility in design (moving the handle up).		Alternatively, the trigger could be connected to the moving pulley bar, which gives some flexibility in design (moving the handle up).

	=Bolt=		== Bolt ==
	Again, similar to [[Cross Bow I]], I want to use a slightly smaller size dowel rod, (1/4 to 1/2 inch). The bolt will have two sections glued together with a fin. The main body of the bolt will simply be dowel rod a few inches long (sized to fit the cross bow) with a rounded front and the back slit to fit the fins.		Again, similar to [[Cross Bow I]], I want to use a slightly smaller size dowel rod, (1/4 to 1/2 inch). The bolt will have two sections glued together with a fin. The main body of the bolt will simply be dowel rod a few inches long (sized to fit the cross bow) with a rounded front and the back slit to fit the fins.

Adamcolton at 17:34, 23 March 2012

2012-03-23T17:34:26Z

← Older revision		Revision as of 17:34, 23 March 2012
Line 8:		Line 8:

	=Bolt=		=Bolt=
	Again, similar to [[Cross ~~bow~~ I]], I want to use a slightly smaller size dowel rod, (1/4 to 1/2 inch). The bolt will have two sections glued together with a fin. The main body of the bolt will simply be dowel rod a few inches long (sized to fit the cross bow) with a rounded front and the back slit to fit the fins.		Again, similar to [[Cross Bow I]], I want to use a slightly smaller size dowel rod, (1/4 to 1/2 inch). The bolt will have two sections glued together with a fin. The main body of the bolt will simply be dowel rod a few inches long (sized to fit the cross bow) with a rounded front and the back slit to fit the fins.

	The fins are cut from a pop bottle and are angled to cause the bolt to spin in flight. Past experience says paint the fins orange so they are easy to find.		The fins are cut from a pop bottle and are angled to cause the bolt to spin in flight. Past experience says paint the fins orange so they are easy to find.

Adamcolton at 19:44, 20 December 2011

2011-12-20T19:44:06Z

← Older revision		Revision as of 19:44, 20 December 2011
Line 13:		Line 13:

	The knock is a small piece glued on the end so the string doesn't split the bolt along the split cut for the fins. This is where I want to get a little more complex. The previous knock design was simply a groove for the string. This time I want to drill a small hole 1/4 from the back end of the knock. Cut a small opening from the back to the hole, with tapered sides. The objective is that the tapered edges will guide the string into the hole but once it's in, the opening will be small enough to prevent the bolt from falling off easily but still allow a smooth release when firing.		The knock is a small piece glued on the end so the string doesn't split the bolt along the split cut for the fins. This is where I want to get a little more complex. The previous knock design was simply a groove for the string. This time I want to drill a small hole 1/4 from the back end of the knock. Cut a small opening from the back to the hole, with tapered sides. The objective is that the tapered edges will guide the string into the hole but once it's in, the opening will be small enough to prevent the bolt from falling off easily but still allow a smooth release when firing.

			[[Category:Projects]]
			[[Category:Workshop]]

Adamcolton at 14:05, 21 September 2011

2011-09-21T14:05:11Z

← Older revision		Revision as of 14:05, 21 September 2011
Line 1:		Line 1:
	=Description=		=Description=
	~~Similar design~~ to ~~[[Cross Bow I]] with~~ the ~~primary difference being~~ (~~metal) spring powered instead of rubber bands. I would link to keep~~ this ~~model as small as possible~~, ~~possibly handheld instead of rifle sized~~. ~~That would mean 18" or less~~, so the ~~bow arms would need to be 1/4 of that or 4.5 inches. The springs are~~ attached to the ~~bow arms 2~~.~~5 inches from~~ the ~~center of rotation meaning 55% force~~ (with ~~a corresponding increase in~~ distance) or a ~~draw~~ force of ~~about 88lbs~~. ~~I will need to put a sirup on~~ it ~~(rope should do just fine). I also want~~ a ~~cocking handle, that should help~~.		Diverging from the "classic" crossbow, I want to use a pulley as the force multiplier (or in this case, reducer). The main mechanism is 2 parallel bars, the front fixed and the back slides, attached to the spring. the drawstring is wrapped around the bars a few times (with force = 90lbs/wrappings and distance = 3in*wrappings). I suggest 4 wrappings, this gives a pull force of 22.5 lbs and draw distance of 12", making it suitable for a handgun design.

	=Trigger=		=Trigger=
	I plan on using a similar trigger mechanism as in [[Cross Bow I]] but instead of a single string catch, I want two smaller catches spaced wide enough apart that I can knock a bolt between them.		I plan on using a similar trigger mechanism as in [[Cross Bow I]] but instead of a single string catch, I want two smaller catches spaced wide enough apart that I can knock a bolt between them.

			Alternatively, the trigger could be connected to the moving pulley bar, which gives some flexibility in design (moving the handle up).

	=Bolt=		=Bolt=

Adamcolton: Created page with "=Description= Similar design to Cross Bow I with the primary difference being (metal) spring powered instead of rubber bands. I would link to keep this model as small as poss..."

2011-09-20T14:16:55Z

Created page with "=Description= Similar design to Cross Bow I with the primary difference being (metal) spring powered instead of rubber bands. I would link to keep this model as small as poss..."

New page

=Description=
Similar design to [[Cross Bow I]] with the primary difference being (metal) spring powered instead of rubber bands. I would link to keep this model as small as possible, possibly handheld instead of rifle sized. That would mean 18" or less, so the bow arms would need to be 1/4 of that or 4.5 inches. The springs are attached to the bow arms 2.5 inches from the center of rotation meaning 55% force (with a corresponding increase in distance) or a draw force of about 88lbs. I will need to put a sirup on it (rope should do just fine). I also want a cocking handle, that should help.

=Trigger=
I plan on using a similar trigger mechanism as in [[Cross Bow I]] but instead of a single string catch, I want two smaller catches spaced wide enough apart that I can knock a bolt between them.

=Bolt=
Again, similar to [[Cross bow I]], I want to use a slightly smaller size dowel rod, (1/4 to 1/2 inch). The bolt will have two sections glued together with a fin. The main body of the bolt will simply be dowel rod a few inches long (sized to fit the cross bow) with a rounded front and the back slit to fit the fins.

The fins are cut from a pop bottle and are angled to cause the bolt to spin in flight. Past experience says paint the fins orange so they are easy to find.

The knock is a small piece glued on the end so the string doesn't split the bolt along the split cut for the fins. This is where I want to get a little more complex. The previous knock design was simply a groove for the string. This time I want to drill a small hole 1/4 from the back end of the knock. Cut a small opening from the back to the hole, with tapered sides. The objective is that the tapered edges will guide the string into the hole but once it's in, the opening will be small enough to prevent the bolt from falling off easily but still allow a smooth release when firing.