Bike Hoist (35lbs max) by cyamate

Last crawled date: 3 years, 1 month ago

This is my Junior year machine design project for chico state mechanical engineering program. it is a bike hoist that is meant for limited space in an apartment or house to store your bike vertically with ease. The assembly is made mostly from Hatchbox PETG except for a few pieces are printed in Taulman 618 Nylon. This is an ADVACED printing project based on the materials used and the pauses that MUST be inserted into the GCode.
I used a 0.6 mm nozzle for everything but the nylon gears.
m3 washers may need to be epoxied to the ends of the two towers out the back of FrameFront4 because the screw head surfaces may be missing, I apologize if you downloaded this before I could fix the model and replace it with FrameFront5.
[UPDATE] 10-09-2017: I posted the STL file for Frame Front5, so if your downloading this after the update you're in the clear. Frame Front4 is missing very small yet important features to allow the 2 m3 body screws to do their job.
Where ever there is a m3 machine screw in this assembly shown in the photos (2 for body, 4 for motor mount, 4 for spool, 4 for battery door) you must find the layer that corresponds to the last open layer for the hexagon voids I created to insert m3 nuts mid print. Creating pauses during the print is crucial, to insert the nuts I partially threaded them onto a long screw and hit them with a propane torch for 2 sec so they can melt their way into the hole. BE SURE the nuts are below the surface of the part or you could damage your brass nozzle.
please notice that the renderings and photos have 2 pulleys top and bottom, where as this model is meant for 3 pulleys top and bottom to increase the mechanical advantage.
Color switching can be done to make the arrows pop out on the front piece. This will require 2 more pauses at the exact right layer, unless your using dual extruder.
Printed Parts:
1X Frame Front#, Frame Back#, Batt Door, Ceil_Bracket, Hook2, Lower_Cablegide, motor bracket, spool#, top pulley holder - PETG
(#) indicates parts that require pauses to insert m3 nuts
6x single pulley - PETG
6X nylon bushing, nylon washer - Taulman 618 nylon
1x BigGear - Taulman 618 nylon
1x DriveGear - Taulman 618 nylon
Hardware:
10x double battery terminals (amazon stopped selling the ones i used. Similar to these; http://a.co/jk0yA94
1x dc female and male charge jack http://a.co/7Yt8o51
1x Double momentary rocker switch http://a.co/5i4lC7O
1x dc right angle gear motor http://a.co/5WFvhQe
6x terminal connectors (small gauge)
8x 608zz bearings
10x rechargable AA batteries
1x Battery charger https://www.amazon.com/Tenergy-Universal-Battery-Charger-Batteries/dp/B003MXMJX8/ref=sr_1_5?ie=UTF8&qid=1507405049&sr=8-5&keywords=battery+charger+tenergy
2x m8x80mm hex bolts
2x m8x50mm hex bolts
8X m8 flat washers
4x m8 nylock nuts
6x m3x25mm machine screws
1x 14"x.125" rubber grommet
1x JST locking connector with 2 conductor paths
9x m3x8mm machine screws
15x m3 nuts (14 nuts heated and inserted mid print last one pushed into drive gear)
3x 8mmx57mm shafts (must be cut to length, same rod stock as most printers use)
small amount of 22awg stranded wire (~2ft)
spool of 65 lb test fishing line (80lb break strength, 60% strengh @knots)
https://www.youtube.com/watch?v=mAbKNog0SMw&t=329s
Note:
-The battery terminals must be glued or epoxied to the frame front and battery door.
-one battery terminal should be cut in half with tin snips to make a positive and negative terminal. solder wires to those terminals and solder the other ends to the middle two terminals on the switch. The tops of the middle two terminals are also connected to the charging port so leave room!!
-polarity doesn't matter until the end when you wire the JST2 connector to the motor, the worst that could happen is when you push the up button it goes down. if that happens, obviously switch something like the polarity of the wires or the orientation of the batteries. that should fix it.
-also if you wire the charger to the male DC jack incorrectly, the charger I posted has a reverse polarity shut down feature.
good luck, happy printing! and try not to make a mess with your epoxy! please comment if you have questions and please post your make if you accomplish this project!!
Chase