3D Printed Repeating Crossbow/Sling Shot Pistol

Description

I've always wanted to have a crossbow pistol for myself, but I never liked the width the bow required. The Fox-III is my attempt at creating such a narrow crossbow/sling shot pistol. It has been inspired by the 3D printed Adderini pistol (https://cults3d.com/en/3d-model/various/adderini-3d-printed-repeating-slingbow-pistol) and the wooden versions created by JoergSprave on the Sling Shot Youtube channel.

My "improvements" are:
** The use of standard surgical tubing looped back on its self to allow for a longer draw without excessive width.
** Different surgical tubing selections allows for a wide range of draw weights.
** A rolling block style string catch to significantly increase the strength of the catch.
** A trigger mechanism that allows the slide to move independently from the actual trigger.
** Using a series of bearings on the high load joints to allow longer service at higher loads.
** A safety switch to help prevent accidental discharges.

Details

All the STL, STEP, and FreeCAD files can be found on GrabCAD.

The rolling block trigger is one of the key features of this design.

The size of the rolling block makes for a very strong string catch, while the trigger design allows for the easy inclusion of a safety switch as well as allowing the slide to move independently from the trigger. The various bearings should allow for smooth operation even with high loads.

I designed two versions of the cocking arm, one that latches and one that does not. The non latching version is held in the cocked position by maintaining a grip on the handle of the pistol. The non-latching version provides an additional safety feature so that it can not be left unattended in the cocked position.

Delrin double v-groove wheels are used for the bow string pulleys as they provide a low cost readily available low friction solution to handling the bow string. The surgical tubing wraps around a custom pulley to double back on itself. This allows the tubing to be longer for the same draw length.Various tubing is available to allow for different draw weights from very light to very heavy.

The files were designed to be printed on a 300x300mm 3D printer, but I also created a split version that can be printed on smaller printers.

Files

STLs.zip

All the STL files

x-zip-compressed - 14.44 MB - 11/11/2023 at 21:39

Download

Steps.zip

All the STEP files

x-zip-compressed - 42.37 MB - 11/11/2023 at 21:41

Download

FreeCAD Files.zip.001

Part 1 of 5 of the FreeCAD files ZIPed with 7zip.

001 - 35.00 MB - 11/11/2023 at 21:41

Download

FreeCAD Files.zip.002

Part 2 of 5 of the FreeCAD files ZIPed with 7zip.

002 - 35.00 MB - 11/11/2023 at 21:41

Download

FreeCAD Files.zip.003

Part 3 of 5 of the FreeCAD files ZIPed with 7zip.

003 - 35.00 MB - 11/11/2023 at 21:41

Download

Components

4 × Double V Groove Wheel

4 × 625-2RS Bearing (5x16x5mm)

8 × MR85-2RS Bearing (5x8x2.5mm)

31 × M3 Hex Nut

6 × M3 x 10 Hex Socket Button Head Screw

Project Logs

Collapse

A Quick Animation

wooddragon48 • 11/13/2023 at 01:56 • 0 comments

Just thought I would upload a quick animation to show how the mechanism works.

Discussions

eduardo wrote 4 days ago

Is there any assemble instructions?

Are you sure? yes | no

Igor wrote 10/18/2024 at 09:16

I got a table 25x22 is there a fitting project?

Are you sure? yes | no

13lenar wrote 2 days ago

in the "FreeCAD File\Parts" folder there are files with "split" in the name. They are ready.

Are you sure? yes | no

CLMB wrote 06/24/2024 at 21:38

What license is this published under?

Are you sure? yes | no

docbrownie wrote 05/10/2024 at 12:33

Hi all - has anyone actually completed this build in real life yet? curious to see the end product and how well it works. I've printed out the peices but i'm still collecting all the hardware!

Are you sure? yes | no

278654727 wrote 02/18/2024 at 02:04

Do you have a steel ball version? Please send me the improved accessory drawings for 8mm steel balls

Are you sure? yes | no

JoachimBrandenburg wrote 01/20/2024 at 17:13

Awesome design! Thank you so much for sharing it! I'm making adjustments for an interchangeable magazine (arrows and steel balls) and 16mm speargun rubber. It's a combination of your design and this one:
https://cults3d.com/en/3d-model/gadget/adderini-reverso-maximus-a-magazine-mod-for-the-adderini-slingbow/makes

Also i'm using a CNC mill to make it :) I'll share the result here soon! <3

Greetz, Joa

Are you sure? yes | no

lalalandrus wrote 01/06/2024 at 20:23

Rear pully broke at draws higher than 30lbs, suggest printing from the freecad upgraded rear pully which has the M5 threaded bolt going through the assembly

Are you sure? yes | no

lalalandrus wrote 01/01/2024 at 00:58

I printed this, lots of little tolerance issues (nuts, clearance holes for screws and bearings, and slide mech.) but overall great design. The rolling latch had to be redesigned for easier engagement. I have successful used this up to a 30lbs draw and slowly adding draw weight to see what it can handle.

Are you sure? yes | no

lalalandrus wrote 01/01/2024 at 01:00

Here are the pictures of the mods

https://ibb.co/Vmqh36Q
https://ibb.co/Tmh5bpb

Are you sure? yes | no

fenexj wrote 01/05/2024 at 14:31

Thanks for this fix, I was going mad trying to get this thing to latch, there are so many tolerance problems with the design, makers beware.

Are you sure? yes | no

lalalandrus wrote 01/15/2024 at 05:13

https://www.thingiverse.com/thing:6435034

Are you sure? yes | no

JoachimBrandenburg wrote 01/21/2024 at 13:02

Awesome! Thank you!

Are you sure? yes | no

timpitner wrote 12/31/2023 at 09:35

I hope you don't mind, but I am working on printing this out at the moment. I have a smaller printer formfactor, so I split your cocking arm with the same type of splice the 2 piece cocking arm (the Adderini uses) for the 220x220 build platform. It seems to be pretty robust for this type of application. I have uploaded the step file to your Grabcad post. If this is not ok, let me know and I will remove it.

Are you sure? yes | no

13lenar wrote 11/07/2024 at 14:18

in the "FreeCAD File\Parts" folder there are files with "split" in the name. They are ready

Are you sure? yes | no

lamgiang1 wrote 12/18/2023 at 21:52

Just finish building this but haven't had the chance to get the rubber band to load it yet. Must be my printer or something but a lot of parts I had to sand down a lot in order to get a good fit. Specially the sliding magazine and the body. It was too tight of a fit for a smooth movement. Printing the cocking arm in two parts weaken it too much and broke during testing at the connection point. I printed all the grove wheel from the cad file. I didn't have all the hardware available, so I had to mod and replace some spot. I replace the grub screw with 3d printed version since I didn't have any on hand. I have to relook at the trigger part because sometimes it would get stuck after pulling the trigger. Would post a picture but not sure how to on this site.

Are you sure? yes | no

jayhawk303 wrote 12/17/2023 at 22:29

what are you using at the ends of the tubing that the eyelets are attached to?

Are you sure? yes | no

wooddragon48 wrote 12/18/2023 at 11:31

Eye bolts with a threaded spacer installed to create the fat section. A tie wrap can be added in front of threaded spacer if required.

Are you sure? yes | no

Lilly wrote 12/17/2023 at 06:10

Where did you get the groove wheels and what STL's are needed for the split version?

Are you sure? yes | no

13lenar wrote 11/28/2023 at 14:28

thanks for your work

Are you sure? yes | no

lamgiang1 wrote 11/26/2023 at 18:42

Will you be including a list of additional parts we need to assemble this?

Are you sure? yes | no

wooddragon48 wrote 11/28/2023 at 19:52

Well, I took the time to update the components list with the majority of the purchased parts that are required.

Are you sure? yes | no

lamgiang1 wrote 11/28/2023 at 22:28

thanks so much for the update. going to try and print this during christmas break.

Are you sure? yes | no

Andrey Factor wrote 11/23/2023 at 00:19

I have been stopping by from time to time and so glad to see it has progressed. The models are excellent vary well generated. Having made quit a few of the other type of Adder units this one has a real tiger setup. Nice to see i am not the only one who is not interested in a spring counterbalance approach.

I am hesitant to make comments on a model this well executed but a 6.5 or 7.5 inch firing stroke will yelled more speed. Your setup has lots of room so using a robber from a spear gun would work for more power. 230 FPS is quite posable

Are you sure? yes | no

wooddragon48 wrote 11/23/2023 at 05:32

Just for your information, the stroke length is set so that bolts in the magazine will drop down on an uncocked string with the tip resting on the string. This allows the magazine to be advanced to cock the bow without the bolt hanging up on the uncocked string. You can see how the bolts will ride up over the string in the animations I posted in a Log entry.

Are you sure? yes | no

Andrey Factor wrote 11/23/2023 at 22:51

LOL yes i am quite aware of the mechanics of the Zhuge Liang setup, I was messing with the Legolini and Adderini science 2018 with serval redesigns for use with camas and such. I/We builder and sell these as we have a engineering company in Farmington MI USA . We send people the price of a down load every time we sell one. Would you be interested in a similar setup? We are in the process of joining with https://cults3d.com/en/users/extremedesigns/3d-models

Darren https://www.facebook.com/profile.php?id=100088553215441

I am from the generation that talks on phones so if you want to do a call just tell us what platform.

Are you sure? yes | no

fenexj wrote 11/14/2023 at 12:52

Just found this project, very excited to build it, thanks for hosting the files for free. Will report back in a week or so when I have it working. Thanks again!

Are you sure? yes | no

James wrote 11/10/2023 at 23:23

where is this at, ive made every crossbow an slingshot gun ive been able to find, i got 3 different versions of the adderini made, 2 slinghammer. the bolthammer, bbhammer nxt 8mm sling shot pistol and a couple more different pistols that shoot 8mm bb or 6.3" bolts. there similar to this ive seen on cults but the wheels mount to the magazine instead of lower on the mainframe of the crossbow. ive been planning on try it but haven't gotten around to it but id love to try this version out.

Are you sure? yes | no

wooddragon48 wrote 11/12/2023 at 04:32

Just added the STL and STEP files as well as the FreeCAD files.

Are you sure? yes | no

Andrey Factor wrote 03/31/2023 at 02:35

Anny plans to provide STL or STEP files ?

Are you sure? yes | no

wooddragon48 wrote 11/12/2023 at 04:32

Just added the STL and STEP files as well as the FreeCAD files.

Are you sure? yes | no

Kaan BEKAROGLU wrote 03/11/2023 at 14:54

When will it be available? I would love to print it!!!!

Are you sure? yes | no

278654727 wrote 02/12/2023 at 15:37

How can I download this crossbow? Can you design a crossbow that fires 8mm?

278654727@qq.com

Are you sure? yes | no

3D Printed Repeating Crossbow/Sling Shot Pistol

Description

Details