Boston Gear FAQ: VFDs, NEMA 17 Stepper Motors, and Getting Parts Fast

I coordinate rush replacements at a Boston Gear distributor, which is a polite way of saying I'm the person you get when a gearbox seizes at 2 PM on a Tuesday and your production line can't stop. Here are the questions I answer every week — with straight answers.

Where do I find Boston Gear distributors when I need parts now?

The official answer is the locator on bostongear.com — punch in your ZIP code and you'll see authorized distributors in your area. That's the right starting point, but there's a faster path.

Call the distributor directly. Don't use the contact form and don't rely on email. Emails sit in a queue; a phone call gets you someone who can check physical inventory in a couple of minutes while you're on the line.

What most people don't realize is how much stock a good distributor actually keeps on hand. We're not sitting on 700-series reducers and motors because we love warehouse overhead — we're doing it because a down line gets expensive fast, and customers remember who helped them first.

Have your part number ready. The nameplate on a Boston Gear unit is almost always metal with the model and ratio stamped in (silver, usually, if it hasn't been painted over a few times). Actually, take a photo of it with your phone — you can text it over while we talk. That alone has saved more than one second call. Scratched nameplates are the single biggest delay I see on rush orders.

What's a VFD?

A variable frequency drive — VFD — controls a motor's speed by adjusting the frequency and voltage of the power going into it. Instead of a motor running at only one speed, a VFD lets you dial it up or down continuously.

The question I usually hear next is, "Is that the same as a soft starter?" No. A soft starter ramps voltage during startup and then runs the motor at full speed. A VFD actively changes the motor's speed throughout operation.

You should be thinking about a VFD when your process actually needs variable speed — conveyors that run at different rates, pumps matching flow demand, fans that don't need to run at 100% all day.

This gets into drive tuning territory, which isn't my specialty. I can't speak to harmonic analysis or selecting the right braking resistor. What I can tell you from the parts side is simpler: the price trend is unmistakable. If you've been putting off a VFD because of cost, that conversation changed in the last few years.

What's the difference between industrial stepper motors and NEMA 17 stepper motors?

Short version: NEMA 17 is a frame size, not a different type of motor. NEMA — the National Electrical Manufacturers Association — sets motor mounting standards. The "17" refers to a 1.7-inch square faceplate.

Industrial stepper motors span several frame sizes — NEMA 14, 17, 23, 34, and larger. A NEMA 17 stepper motor is one of the most common for smaller automation: lab equipment, 3D printers, compact conveyor sections, and light positioning axes. Depending on the winding, it usually lands in the 40-80 oz-in holding torque range. If that's not enough, NEMA 23 (2.3-inch faceplate) or NEMA 34 will typically give you several times the torque.

The mistake I see constantly: matching the frame size and assuming the torque curve will work because the bolt holes line up. The frame tells you the mounting dimensions. The torque curve tells you whether it will actually move your load. Check the curve, not just the number.

What's the most common mistake in rush gearbox replacements?

Mounting configuration. It's not the gear ratio and it's not the shaft diameter — it's the mounting. I've made this mistake myself.

The part number looked identical to the original unit, and I thought, what are the odds? The odds caught up with me when the replacement arrived with the right ratio, right input speed, right shaft — and a foot configuration that matched every hole except one. The customer's maintenance crew spent three hours fabricating an adapter plate that should never have been needed.

That's when we added a photo verification step. Before we commit to a rush ship date, we ask for a photo of the nameplate and a photo of the mounting arrangement. It takes the customer about two minutes, and it's saved us more than once since.

We didn't always have that process. The third time a mismatch cost someone time and money, I finally made a checklist and baked it into our order workflow. Should have done it after the first time.

How fast can a Boston Gear replacement actually arrive?

Realistic answer: it depends on what's in stock and where it's sitting. The quickest I've been part of was a same-day pickup. A packaging line was down, the customer needed a NEMA 23 stepper motor and a matching drive, and it was in our warehouse. They came and got it; the line was running the next morning. No drama.

The more typical urgent case takes one to three days. If your local distributor doesn't have it, someone in the regional network usually does. Next-day freight is usually a few hundred dollars depending on size and weight — annoying, but cheap compared to a stopped line.

In March 2024, we had a client with a failed 700-series worm gearbox and a contract carrying a $50,000 penalty for late delivery. The normal path was three weeks out of stock. We found the exact unit at another distributor, the client paid roughly $180 in premium freight on top of the $2,100 base cost, and the gearbox was on their dock 36 hours later.

Ask your distributor for a network stock check — not just "is it in your building" but "what's available in the region?" That's where the speed actually lives.

Should I replace a fixed-speed gearmotor with a VFD setup instead?

This is where I genuinely see the industry shifting. What was best practice in 2020 isn't automatically the right call in 2025.

VFD pricing has come down enough that they're a routine option. A solid 2 HP VFD runs somewhere in the $200-400 range from major manufacturers (depending on enclosure rating and features, based on invoices I've seen through 2024). When you're already paying for a motor replacement, the incremental cost of going VFD-ready is smaller than most people assume.

But there's a counterbalance. If your application is fixed-speed, has been running fine for years, and isn't going to change, a VFD adds complexity without adding value. The fundamentals still hold — not every process benefits from variable speed.

The middle path I usually recommend: when a gearmotor fails and needs replacing anyway, quote it both ways. Direct replacement versus VFD plus inverter-duty motor. The second number has surprised more than one customer — in a good way.

I can only speak to what I see from our ordering desk. If you're running a continuous, fixed-load operation with no speed changes planned, sticking with a straight gearmotor is a solid position.

What's the deal with "ski gear boston" searches ending up here?

It happens a lot, and I'll be straight with you — I can't fully explain search engines. Boston Gear has been making gears and power transmission components in Massachusetts since 1877, which predates the internet by a comfortable margin. Yet somehow "ski gear boston" and our pages have been tangled together for years.

If you came here looking for ski equipment: sorry, we can't help with that one. I hope you found what you need elsewhere.

If you're looking for industrial gearing, speed reducers, stepper motors, or drives — you're in the right place. And if you need a part faster than the usual turnaround, call your local Boston Gear distributor and ask for the person who handles urgent orders. That's what I do.