Gridfinity Tamiya Racing-Pack storage bin

Description

Gridfinity bin that accommodates three Tamiya stick packs with Tamiya-, XT60- or Deans/T-Plug.

## Overview

This 2×4 Gridfinity allows you to conveniently store 6-cell stick-pack battery packs commonly used in Tamiya RC-Cars, especially the vintage models. 

Features

• Stores 3 stick-packs in a space efficient manner.
• Keeps your cables and connectors tidy.
• Plug-Rests are compatible with Tamiya-, XT60 and Deans/T-Connectors.
• Batteries can be charged while in the storage bin.
• Keeps labels on the side readable

Cleaning

When using this at the track it may get dirty. To clean this bin, just wash with water and brush off any dirt. Take care that the plug-rests are clean as well.

Before putting your batteries back into the bin, let the bin dry completely.

If you're lazy (like me):

Under certain conditions, you may put this in the dishwasher.

• You've removed all batteries from the bin.
• Only when printed in PET-G, ABS or ASA because of their thermal deflection properties.  (PLA will deform from the hot water in your dishwasher.)
• You followed the print setting recommendations which should result in a water-tight object.
• You did not put any magnets in the bin, not even when glued in. Heat > 80°C will likely damage most magnets. They also might get ripped out by water pressure and end up sticking to the inside of your dishwasher. Not worth the risk of damaging your household appliance.
• Orient the bin upside down, so hot water doesn't get caught in the battery compartments.
• Don't use an industrial or gastronomy/restaurant dishwasher. These use higher temperatures and much higher pressure which is likely too much to handle for a print.

Printing

Recommended materials

Material recommendations in this order.

• PET-G (My personal favourite, since it's easy to print without an enclosure. Widely available and cheap. Excellent recyclability.)
• ASA/ABS

These materials have suitable properties for this use-case.

• Heat deflection: These materials will not deform when putting in a hot battery.
  • When putting back your battery immediately after a race, it might still be hot.
  • When fast-charging a battery it will become hot as well.
• Impact resistance: Sometimes you drop an item. These materials should be able to take a beating without shattering when when the bin hits the ground at your workbench or at the track.

Any colour is fine. If you print a bunch of these bins, you may even want to colour-code the battery chemistry (NiCd, NiMH, LiIon), or model compatibility.

Print orientation

The .stl comes correctly oriented on the build plate. No need to flip it around.
 

Print settings

When putting in three 5.000 maH NiMH batteries the whole thing can easily weigh over 1.5kg. Creating a sturdy print is vital. Using my recommended settings allows you to print this in under 6 hours on a stock Průša MK4.

• Use a 0.4mm nozzle
• Start with the 0.20mm STRUCTURAL preset in Průša Slicer
• Print Settings > Layers and Perimeters > Vertical Shells: Set perimeters to 4
• Print Settings > Layers and Perimeters > Advanced: Set Seam position to random
• Default infill type Grid at 15% is fine
• There's no point in ironing horizontal surfaces on this model. (Adds about an hour of printing time.)

Since this is a rather large bin, let your print bed heat-soak properly to avoid warping of the corners. (Yes, even with PET-G.) I recommend letting it slowly cool down to room temperature before removing it from the bed, again to avoid warping.

Printer compatibility

Any printer with a 180mm or larger bed. This includes the Průša mini, RatRig V-Minion and any larger printer. (This bin won't fit a Voron 0.x.)

Post processing

Like with most gridfinity bin, you can put in magnets. This bin will accept disc magnets with ∅ 6mm, and thickness 2mm. They should be press fit, in case they're not, you can glue them in with CA-/Super-glue or epoxy.

Battery Compatibility

Compatible batteries

Suits 6-cell stick-pack/racing-pack size rechargable batteries. (Topology must be 2 sticks of 3 cells.)

Incompatible batteries

• Saddle packs (2 sets of 3 cells side-by-side connected by a cable. These were sometimes used in vintage racing buggies and pan-cars.)
• HumpPacks (5 cells next to each other aligned on the long edge, with a single cell on top at position 4 forming a hump, usually in a hardcase. NiCd chemistry)
• 8.4V Racing pack (2 sets of 3 cells side-by-side, with a 7th cell at a right angle at the far end. Usually NiCd or NiMH chemistry.)
• LiPo (Lithium Polymer) batteries of any kind. Not even if they mechanically do fit. LiPos must always be stored in a fire-safe enclosure. 

Connector Compatibility

Connectors can be conveniently seated in these small compartments.

Compatible Plugs

The plug rest is compatible with multiple connector types. From left to right:

• ✅ XT60 (Including XT60+ and other variants)
• ✅ Tamiya 7.2V
• ✅ Deans/T-Connector
• (Tamiya 8.4V connector but the battery compartment does not fit an 8.4V racing-pack! You shouldn't be using an 8.4V connector on a 7.2V battery anyway.)

Gridfinity specifications

Dimensions: 2 × 4 grid units

Height: 4 height units

Stackability: Yes, but only when empty

Context
 

Gridfinity

Gridfinity is an open-source specification for an organisational system that prioritises overview over storage-density. It's highly flexible and basically all items can be modified to exactly fit your specific needs. All items can be 3d-printed.

Gridfinity was introduced by Zack Freedman on their YouTube Channel, Voidstar Lab.  
Gridfinity: Your Ultimate Modular Workshop is FREE!

You can find unbounded amounts of printable parts for gridfinity on Printables and other 3D-Model platforms.

Tamiya RC-Cars

Tamiya is a manufacturer of popular radio controlled cars and vehicle build-up kits. RC vehicles are a lot of fun to drive and a joy to build.

Model Customisation
 

Source Code

OpenSCAD source code is included if you want to customize this to fit your exact battery pack or plug. 

Parameters for customization

// Diameter of an individual cell (including shrink-wrap)
cell_diameter           = 25; //mm

// Length of an individual cell
cell_length             = 44; //mm

// Gap between individual cells of the sticks
cell_padding            =  2; //mm

// Gap between the individual sticks in a pack,
// irrelevant since packs are on their side in this bin
cell_padding_lengthwise =  0; //mm

// Gap between the stickpacks
stick_padding           =  1.41; //mm

// Gap between the whole pack and the bin
pack_clearance          =  1; //mm

// rounding the edges, so packs and wires don't get damaged by sharp edges
pack_rounding           =  0.5; //mm

cable_cutout_diameter    = 18; //mm How much space to leave for cable outlets
cable_cutout_padding     = 20; //mm
cable_padding_lengthwise = 25; //mm Gap between the individual sticks in a pack

pack_asymmetric_placement_shift = 12.6; //mm
 // Moving the packs asymmetrically to one side, so we can get
 // clearance for wires and plugs
 // make sure you don't run into the stacking lip at the edge

Feedback welcome!

Do you have a battery pack that matches the kind this bin is designed for, but still doesn't fit exactly? Send me the measurements of that battery and I can see if I can add compatibility with that pack as well.

Post a make!

If you printed one of these, please like and post a make!