Heat Press T-Shirt Ruler Guide — Setup, Placement and How to Fix Warping
The polycarbonate t-shirt ruler that stays on the platen up to 320°F (160°C), so you can press, check and re-press without re-aligning.
Quick Fixes — Read This Before Returning
“My ruler warped.” — It’s reversible
This is the most common thing customers tell us about. Many heat presses run hotter than the dial says, and above 320°F (160°C) the polycarbonate softens and takes a curve. A warped ruler is not a damaged ruler. Do not throw it away.
- Set the heat press to 320°F (160°C).
- Place the warped ruler on the platen with no shirt underneath.
- Cover it with a silicone sheet.
- Close the platen for 30 seconds.
- Lift it out with heat-rated gloves and lay it flat to cool — a heavy book on top helps.
Still curved? Repeat. Most warps come out in one pass; bad ones may take two or three. Warning — the ruler will be hot.
Stop it happening again
- Check your press temperature with an infrared thermometer — many read 5–15°F low.
- Always cover the ruler with a silicone sheet.
- For transfers above 320°F, use the two-stage method in Step 4.
Other quick fixes
- Pockets or sleeves? Use the Pocket and Sleeve Placement Guide instead.
- Sticky film on the ruler? Some legacy Amazon stock ships with protective film. Peel it slowly before the first press.
Which T-Shirt Ruler Do I Have?
- PPG-4 Full Shirt and PPG-5 Neck and Chest (Heat-Safe) — thin polycarbonate, rated to 320°F, ships in a cardboard tube. This guide is for you.
- PPG-6 Pocket and Sleeve (Heat-Safe) — see the Pocket and Sleeve guide.
- PPG-1, PPG-2, PPG-3 Standard — 1.5mm PETG, not heat-safe. See the Standard T-Shirt Ruler guide.
Before You Start
- In the tube: one CLPA Perfect Pressing Grid (PPG-4 or PPG-5) with neckline references for adult round neck, V-neck, youth and infant, a printed instruction book and heat-press timing cards.
- Have ready: a permanent marker, double-sided or heat-resistant tape, and a silicone sheet.
How To Use a Heat Press T-Shirt Ruler — Step by Step
Step 1 — Lay out the design on the grid first
Place the grid over your printed design, or over a shirt with the transfer where you want it, and mark each transfer’s position on the top of the grid. The marked side never touches the shirt.
Step 2 — Load the grid
Turn it over and tape the transfers in the marked positions. Double-sided tape sits between the grid and the transfer backing, never on the shirt.
Step 3 — Position on the shirt
Turn the loaded grid back over, lay it on the shirt and line up the front-edge mark with the collar using the neckline curve.
Step 4 — Press
Cover the grid with a silicone sheet before closing the press.
- Transfer temperature at or under 320°F (160°C): press for the transfer maker’s time plus 5 seconds.
- Transfer temperature above 320°F: press at 300°F (150°C) for 10 seconds to tack the transfer. Don’t peel. Remove the grid, reset to the target temperature and press for the full time without the grid. Peel hot or cold as the transfer maker says.
Warning — the grid will be hot. Use heat-rated gloves or a peel tool.
Works With
HTV vinyl, DTF, sublimation transfers, screen-print transfers and embroidery placement, on any heat press brand (Cricut, HPN, Stahls’, Hotronix, Geo Knight and others). If your sublimation press runs at 385°F or higher, always use the two-stage method.
Looking After Your Grid
- Clean marker off with isopropyl alcohol or methylated spirits. No acetone or abrasive cleaners.
- Store flat, or rolled in its cardboard tube. Keep out of long-term sunlight — the UV ink is rated for ten years indoors.
When to Email Us
Email sales@clpa.au with your order number and a photo if your tool arrives damaged, you ordered the wrong size, or a printed line looks off-register. We aim to reply within one Brisbane business day — if you are in the USA or UK, remember we are a day ahead. We make every tool in-house, so we can usually replace, exchange or quote a custom size faster than a return would take.
Returns and Warranty
Unused items can be returned within 30 days of delivery in original condition — see our Refund Policy. Every CLPA tool carries a 12-month manufacturer warranty against defects in materials and workmanship. Bought on Amazon? Amazon’s return policy applies to your order, and our warranty still covers the tool.
More help: Frequently Asked Questions.
We Make What We Sell
Custom Laser Products Australia (CLPA) is a small veteran-owned family business. We design, laser-cut and UV-print every tool on the Sunshine Coast, Queensland. We are the manufacturer, not a reseller.
CLPA Customer Support · sales@clpa.au · clpa.au