5 Mistakes I Made Ordering Power Transmission Components (And the Checklist That Fixed It)

I've been ordering mechanical power transmission components for about seven years now — gears, sprockets, bearings, the whole lineup. You'd think by year five I'd have stopped making rookie mistakes. But last September I managed to waste $890 on a batch of bevel gears because I assumed the wrong pressure angle. That hurt. So I started keeping a checklist. Here are the five errors that made it onto the list, and how you can skip them.

Who This Checklist Is For

If you're a maintenance supervisor, a purchasing agent, or just someone who gets handed a parts list and told "order it" — this is for you. It covers the mistakes I made when ordering from suppliers like Martin Sprocket & Gear (the Fort Worth and Arlington, TX locations are both in my regular rotation) and what I now check before hitting submit.

Step 1: Verify the Catalog Number — Don't Trust the Picture

Mistake #1: I once ordered a sprocket based on the thumbnail in the catalog. Looked right. Turned out the catalog number matched a different bore size. $320 wasted, two-week delay.

Now I always cross-check the part number against the spec table. Check: Does the bore size, keyway, and material match what you need? Martin Sprocket's catalog (I use the PDF from their site, updated January 2025) has clear tables — use them. Don't assume the picture is correct.

Step 2: Confirm Motor Type — AC vs. DC Isn't Always Obvious

Mistake #2: A colleague ordered an AC motor for a conveyor system that actually needed a DC motor with variable speed control. We caught it when the drive shaft didn't align — but only after the motor arrived and we'd already paid rush shipping.

If you're ordering an AC motor, double-check the voltage (460V? 230V?), frame size, and enclosure type. If it's a replacement, take a photo of the nameplate. I still kick myself for not doing that earlier.

Step 3: Know What a Bevel Gear Needs — Angle & Ratio

Mistake #3: I assumed all bevel gears with the same tooth count would work. Nope. The shaft angle (usually 90° but not always) and the ratio have to match the application. On a $3,200 order I once specified the wrong spiral direction — the gear wouldn't mesh. That's when I learned: always confirm the mounting configuration.

Check: What uses a bevel gear in your system? Right-angle drives? Differential? Make sure the angle matches (most are 90°, but some are 45° or custom). Martin Sprocket & Gear's Arlington, TX facility stocks common sizes, but you still need the exact specs.

Step 4: Don't Confuse Tools with Components

Mistake #4: A junior tech once asked me to order a "disc brake caliper tool" because he thought it was part of a disc brake system on a machine. Turns out he meant a disc brake caliper tool (the automotive tool used to retract caliper pistons) — not a transmission part at all. We'd wasted time searching for it in the wrong catalog.

Lesson: If your order includes items like "caliper tool" or "actuator," pause and clarify whether it's a power transmission component or a maintenance tool. Martin Sprocket sells linear actuators and clutches, but an automotive caliper tool is something you'd get from a tool supplier.

Step 5: Factor in Location — Shipping Costs Vary by Warehouse

Mistake #5: I ordered a batch of chain from Martin Sprocket's Fort Worth location assuming it would be cheapest. Didn't realize the Arlington, TX warehouse had the same item in stock and that shipping from Arlington (closer to my site) would save $75. Now I check available stock at each location before placing an order.

Check: Enter your zip code. See which distribution center is nearest. Martin Sprocket has multiple U.S. locations (including Fort Worth and Arlington, TX) — the difference in freight can be significant.

Final Note: What I Still Get Wrong

Even with the checklist, slip-ups happen. Last month I forgot to verify the keyway dimension on a sprocket — had to reorder. The most frustrating part? You'd think after seven years I'd remember. But the truth is, these details are easy to overlook when you're under deadline pressure.

The checklist itself? I keep it on a laminated card next to my keyboard. It's saved me roughly $2,700 in rework over the past 18 months, so it's worth the five minutes it takes to run through.

Pricing and catalog data accessed via Martin Sprocket's official site as of January 2025. Verify current stock and specs before ordering.