Design a 3D-printable backpack clip for a hydration tube with Claude Code, Codex and Antigravity (partial)
- Posted
- by Yadullah Abidi (MakeUseOf)
- Last checked
- Method:
- How we verify
Evidence: Article or interviewA newsletter, journalist or interview account of what happened.
PartialThe source says it only partly worked, or had a significant problem a person had to deal with.
What went wrong: All three parts printed, but each needed changes: one had no lock, one was bulky, one used wrong dimensions.
Context: In a comparison test: from a head-to-head chatbot review, not a standalone agent test.
Outcome
Yadullah Abidi needed a replacement clip to hold a hydration bladder's 14mm drinking tube on a closed webbing loop measuring 57 x 24mm on a backpack strap. For MakeUseOf, Abidi gave Claude Code, Codex and Antigravity the same measurements and prompt, with each connected to FreeCAD to build, check and export the part. Codex made the cleanest model, but its T-head had no positive lock. Claude Code iterated and produced a clip that worked, but at 24 × 61.8 × 36 mm it was bulky and needs refinement. Antigravity needed three tries, once showing ASCII art, and its best design was closest to the intent but used wrong dimensions. Abidi printed all three; none was a clean win.
AI tools
Claude Code, Codex, Antigravity
Prompt Improved prompt
Our fuller version of the source's prompt, or one written to avoid a problem in the source. Not tested by the poster. It doesn't change what happened in the source.
Run this task now, exactly as written below. Everything you need is here, so start straight away and only stop if something required is missing or a rule below tells you to. Goal: Design a small replacement part I can 3D print that fits and holds up in real use. Fill in before running: - What the part must attach to and hold, with measurements in mm: [MEASUREMENTS] - Photo of where it goes: [PHOTO] - Printer, nozzle and material: [PRINTER AND MATERIAL] Rules: - Pick one attachment approach, explain why in two sentences, and make sure it locks in place rather than just sitting there. - Keep it as small as the job allows; no needless bulk. - Design it to print without supports, and state the print orientation so layer lines don't run across any part that flexes. - Use only my measurements; if one is missing, ask rather than assume. - Check the model is one watertight solid, report its bounding box, and export STEP and STL files. - Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify. Output: STEP and STL files, two preview images, and the three dimensions most likely to need tuning. You'll know it worked when: the printed part fits first or second time and stays put when the strap moves.
Customize this prompt
Answer the questions below and we'll put your answers into the prompt for you. You can leave any of them empty.
Photo of where it goes
You'll attach this in the chat tool, not here. Add the file in the chat before you send the prompt.
Your prompt
Run this task now, exactly as written below. Everything you need is here, so start straight away and only stop if something required is missing or a rule below tells you to. Goal: Design a small replacement part I can 3D print that fits and holds up in real use. Fill in before running: - What the part must attach to and hold, with measurements in mm: [MEASUREMENTS] - Photo of where it goes: [PHOTO] - Printer, nozzle and material: [PRINTER AND MATERIAL] Rules: - Pick one attachment approach, explain why in two sentences, and make sure it locks in place rather than just sitting there. - Keep it as small as the job allows; no needless bulk. - Design it to print without supports, and state the print orientation so layer lines don't run across any part that flexes. - Use only my measurements; if one is missing, ask rather than assume. - Check the model is one watertight solid, report its bounding box, and export STEP and STL files. - Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify. Output: STEP and STL files, two preview images, and the three dimensions most likely to need tuning. You'll know it worked when: the printed part fits first or second time and stays put when the strap moves.
Scroll to see the whole prompt. Your answers show in green.
2 blanks are still empty: What the part must attach to and hold, with measurements in mm; Printer, nozzle and material. They'll stay in brackets in your prompt, so the chat tool may ask you about them.
What you type stays in this browser tab. We don't send it or save it, and it's gone when you leave the page. If you use a "Try this in" button, your answers go to that tool as part of the prompt.
Try this in:
This prompt has blanks to fill in, like [MEASUREMENTS]. We'll copy it instead of filling it in, so you can edit it before you send.
Opens in a new tab. We don't see what you send.
These links are only a shortcut. We're not affiliated with OpenAI, Google or xAI, and your results may not match the source.
The prompt they actually used
The exact prompt from the source.
Design a 3D-printable replacement clip for the closed (both ends sewn) webbing loop on the lower edge of my backpack's padded shoulder strap (see attached photo) that holds a hydration bladder's 14 mm drinking tube. The loop is 57 mm long and 24 mm wide, pick either a T-head/rotate-to-lock tab through the opening or a snap-around clip over the webbing, justify it in two sentences, and don't rely on the flaking reflective coating for grip. It must stay put while walking and running, and the tube must pull out and push back in one-handed. Print in PLA on a 0.4 mm FDM printer with no supports, and state an orientation where layer lines don't run across any flex arm or neck. Since PLA is brittle and creeps, favor a rigid lock or a thick, long, filleted flex arm, with 1.6 mm minimum walls and 0.2 mm clearances. Deliver .step and .stl files and the 3 dimensions most likely to need tuning. ask questions: state assumptions, run the script to confirm a watertight solid, report the bounding box, render two views, and keep it one part with no hardware.
Optional stronger version
Our rewrite with extra checks. The poster didn't test it.
Run this task now, exactly as written below. Everything you need is here, so start straight away and only stop if something required is missing or a rule below tells you to. Goal: Design a small replacement part I can 3D print that fits and holds up in real use. Fill in before running: - What the part must attach to and hold, with measurements in mm: [MEASUREMENTS] - Photo of where it goes: [PHOTO] - Printer, nozzle and material: [PRINTER AND MATERIAL] Rules: - Pick one attachment approach, explain why in two sentences, and make sure it locks in place rather than just sitting there. - Keep it as small as the job allows; no needless bulk. - Design it to print without supports, and state the print orientation so layer lines don't run across any part that flexes. - Use only my measurements; if one is missing, ask rather than assume. - Check the model is one watertight solid, report its bounding box, and export STEP and STL files. - Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify. - Tell me how to print a quick test piece of just the attachment so I can check the fit before the full part. Output: STEP and STL files, two preview images, and the three dimensions most likely to need tuning. You'll know it worked when: the printed part fits first or second time and stays put when the strap moves. Before you finish: re-read my goal and constraints, check your answer against each one, and list anything you assumed or couldn't confirm.
Source
https://www.makeuseof.com/claude-chatgpt-gemini-design-part-3d-printed/
Related cases
- Stop a mechanic fitting the wrong-polarity car battery from one photo with ChatGPTRecreated promptEvidence: Screenshots or logsBeginner-friendly
When a mechanic arrived with a new battery for the poster's family car, the poster photographed the battery code and asked ChatGPT. It flagged that the battery was left-hand polarity while the Tata Punch needs right-hand, said new terminals would be needed for that reason, listed risks such as cables not reaching, sparks and warranty claims being refused, and recommended a DIN44R right-hand battery. The poster told the mechanic to bring the correct one, and the mechanic agreed to.
ChatGPT · Personal · Source date:
- Work out how to remove and repair a 1980s dishwasher from its model number with ChatGPTRecreated promptEvidence: Described by posterPartial
A hired contractor couldn't work out how to remove the poster's grandparents' 1980s dishwasher, which was attached at the top. Hacker News user MattGaiser gave ChatGPT the model number; it explained why it wouldn't come out (a part had to be disconnected), found a replacement part and gave step-by-step instructions for taking that part out. They didn't end up buying the new part.
ChatGPT · Personal · Source date:
- Fix a washing machine that won't fill using Gemini, after ChatGPT picked the wrong partRecreated promptEvidence: Described by poster
A poster described their broken washing machine to Gemini, which helped them run diagnostics, found it wasn't taking in water and pointed to the inlet valve. They used ChatGPT's shopping help to find and order the part, but the first part didn't fit even though ChatGPT said it would. They installed the right one with Gemini's guidance in about 1.5 hours total, saving about $120 on labour.
Gemini, ChatGPT · Personal · Source date: