Saw: Chainsaw & Fuel Mix Calc — Support

Need help?

Email roman.kopaliani@gmail.com with your question. Please include:

• What you were trying to do
• What happened instead
• The app version (Saw → More → About)

Frequently asked

What's free and what's in Saw Pro?

Free forever: the 2-stroke fuel-mix calculator (any ratio, any tank size, oz and mL), the complete chain-pitch → file-size chart, and the Cut Safe reference. Saw Pro ($6.99, one-time) unlocks Chain ID (rivet measurement → the exact chain to buy) and the per-chain sharpening tracker. No subscription.

What ratio should I mix?

Per Husqvarna and Stihl guidance, modern 2-stroke equipment runs 50:1 (about 2.6 fl oz per US gallon, 20 mL per litre) with a JASO FD-class oil — and your owner's manual is final. The app offers 50:1, 40:1, 32:1, 25:1 and custom ratios because older equipment differs; it never asserts a ratio for a specific machine.

Why does the app nag about ethanol and old fuel?

Per OPEI's "Look Before You Pump" campaign: small engines are made for fuel with no more than 10% ethanol (E10) — E15 and higher blends damage them and void warranties — and ethanol-blend fuel goes stale in roughly 30 days, gumming and corroding fuel systems. Mix what you'll use.

Which file does my chain take?

Per Oregon Products file-guide sizing: 5/32″ for 1/4″ and 3/8″ low-profile chain, 3/16″ for .325″, and 7/32″ for 3/8″ and .404″. Filing angles are set per chain model — typically 25–35° top plate — so confirm the exact figure on your chain's box or Oregon's filing chart.

How do I know which chain to buy?

Match three numbers: pitch (distance across three consecutive rivets, divided by two), gauge (drive-link thickness), and drive-link count. All three are usually stamped on the guide bar; Chain ID works pitch out from your measurement and assembles the full spec.

When does a chain retire?

When its cutters are filed back to the wear mark stamped on them — that's the manufacturer's rule, not a sharpening count. The tracker logs your count as a planning proxy and says exactly that.

Does it work offline?

Yes — Saw never makes general network requests. The exception is Apple's StoreKit (to fetch the unlock price and restore purchases). All calculations and your chains are local.

Is Saw a guarantee?

No. Saw is an educational reference that shows published guidance alongside your inputs. Your equipment's owner's manual is final, and chainsaw work is dangerous — follow OSHA guidance and wear full PPE.

Refunds

Purchases are handled by Apple. Request a refund at reportaproblem.apple.com.