[](https://hackmd.io/hFu-JuHMTZuSDLUrKT-LZQ)
# `frame-build-sturdy_cots` Trolley with 17x17 profile and COTS parts
:::info
(c) Holger Kienle
License (if not stated otherwise below): [CC BY-SA](https://creativecommons.org/licenses/by-sa/4.0/)
:::

## Properties and constraints

The self-imposed (design) constraints of this build are:
- Use the [frame-17x17](/@hkienle/frame-17x17) design to better understand if there are structural problems for a "normal" use case (20kg load).
- Primarily **COTS parts**:
1. Ideally, a part associated with a norm/standard and many suppliers.
2. A part with several suppliers.
3. A part that can be purchased from a single supplier/source.
4. (A part that has a single supplier but many potential alternatives with (slight) variations that are also applicable.)
- No 3D-printed parts.
- Feasible to build with:
- simple hand tools
- pillar drill or drill press (recommended for precision and convenience)

## TLDR: Shopfloor sheet
:construction:

## Spec
- :exclamation: `design-17x17` <- `frame-design`

(For convenience, in the following some key specs are repeated.)

### Beam profile and fasteners
- `beam-17x17`
- `s`=17mm
- `beam-material`: pine (:de: Kiefer)
- `fastener-m4` (M4)
- `screw-m4-40mm`
- `nut-m4`
- `nut-m4-height`: 3.1mm
- `washer-m4`
- `washer-m4-dia`: 16mm
- `washer-m4-height`: 1mm
- `fastener-material`: zinc-plated, stainless steel (304)

#### Tri-joint layout
- A single tri-joint has 3 screws, 3 nuts and 6 washers.

### Frame add-Ons
- : See [part-bikehandle_cover](/@hkienle/part-bikehandle_cover).
- Length (`L`): 26,5cm (`beam-15` =< `L` < `beam-16`)
- -board: See [bag_platform](/@hkienle/bag_platform).
- Width: 340mm (= `beam-20`)
- Depth: 238 (= `beam-14`)
- Thickness: 10mm
- Material: MDF (orange colored, scavanged)

### Wheel mount
- See [wheel_mount](/@hkienle/wheel_mount-)

## Procurement (`buy`)
- 2x 2400mm [square bars](/@hkienle/part-square_bar) (:de: Quadratleisten): Buy [Obi](https://www.obi.de/search/quadratleiste%2017/).
- 1 bar corresponds to ~`beam-141`.
- 18x `screw-m4-40mm`: Buy [AliExpress](https://de.aliexpress.com/item/33008696963.html).
- 36x `washer-m4-16mmx1mm`: Buy [AliExpress](https://de.aliexpress.com/item/1005007189912344.html).
- 18x `nut-m4`
- : Buy [AliExpress](/@hkienle/part-bikehandle_cover#AliExpress).

## Frame

### Manufacture of beams (`cut` and `drill`)
- Do with generic instructions: [beam-mfg](/@hkienle/beam-mfg).

### Assembly of frame
- Do with generic instructions: [frame-assy](/@hkienle/frame-assy).
- It is recommended to install [
](/@hkienle/part-bikehandle_cover)-addon to -beam before mounting  to the frame.