Gang Sheet Builder setup

1. Install

Install the app from the Shopify App Store. Shopify asks you to approve the permissions it needs, then opens the app inside your admin.

On first open the app sets itself up:

• it creates a product called Custom Gang Sheet and publishes it to your Online Store
• it prices that product at your rate per linear inch
• it switches on the checkout rules that keep sheet prices honest

2. Set your numbers

Open the app and work down the settings screen. These are the numbers the builder measures against.

• Roll width. The width your printer runs, in inches. Commonly 22.
• Price per linear inch. Your rate. Saving pushes it onto the product.
• Minimum length. The shortest sheet you will accept an order for.
• Maximum length. The longest single sheet you can print.
• Gap between designs. Clear space around every piece, so sheets can be cut apart. 0.2 inches is a common starting point.
• Store name and colours. What customers see at the top of the builder.

Changing the price later is the same action: edit the field, save, and the product follows.

3. Add the button

The builder is opened from a button you place in your theme. It is an app block, so it goes in from the theme editor rather than by editing code.

1. In your Shopify admin, go to Online Store, then Themes, then Customize.
2. Switch the page selector at the top to a product page.
3. In the product information section, choose Add block.
4. Open the Apps tab and pick Gang sheet builder.
5. Drag it where you want it, set the label and colours, then Save.

Most stores put it on the gang sheet product page itself. You can add it to any product page, and to more than one.

4. Place a test order

Open the button as a customer would, upload a design, and let the builder fill a sheet. Check that:

• the sheet width matches your roll
• the total matches your rate times the sheet length
• the cart line shows the length, the width and a preview

Shopify's Bogus Gateway lets you complete the order without taking a real payment, so you can see how one arrives.

Production files

Every sheet gets a job reference, which appears on the order line as Builder Job ID. The line also carries a preview image, the sheet length and the sheet width.

The preview is for checking the layout at a glance. The full resolution print file is produced for that job and downloaded from the app, so nothing has to be requested from the customer after the fact.

Files are kept for the retention period in your settings, 30 days by default, and cleared after that. Download anything you need to archive before it lapses.

Checkout rules

A gang sheet is priced by its length, and the cart carries that length as the line quantity. Two things would break that, and the app blocks both:

• adding the gang sheet product without going through the builder, which would order a sheet with nothing on it
• editing the quantity in the cart, which would pay for a shorter sheet than the one produced

Both checks run inside Shopify's checkout rather than in the browser, so they hold even if someone edits the page. A customer who hits one sees a short explanation and can rebuild the sheet at the size they wanted.

Troubleshooting

The button does not appear in the theme editor

Check that the app is installed and that you are editing a product page. Blocks appear under the Apps tab, not the default block list.

Add to cart does nothing

Open the app's settings and check the gang sheet product is connected. If the product was deleted from your catalogue, the app can create a new one.

The price is wrong

The price comes from the app, not from the product. Set the rate in settings and save; there is also a Resync price button that pushes the current rate onto the product.

A customer cannot check out

Ask what the message said. Both checkout rules explain themselves, and both are cleared by removing the line and building the sheet again.

Something else

Write to support@merchui.com with your store address and, if there is one, the job reference from the order.