Dynabrade 51703 Straight-Line Pencil Grinder
- 50000 rpm turbine air motor
- Pneumatic, 1/4 inch NPT air inlet
- 1/8 inch collet, rear exhaust
- .1 hp in the title, 1 hp in the specs
- 12.64 oz, non-vacuum
Last refreshed Aug 4, 2026 · Based on the Amazon listing and published specifications, not hands-on testing.
A lightweight air-driven pencil grinder with a turbine motor and a small collet. Its horsepower is listed two ways and the warranty requires registration, so read both before buying.
As an Amazon Associate I earn from qualifying purchases. ProductDome earns a commission when you buy through links on this page.
ASIN: B00206TDE6Model: 51703Category: Power Grinders
Overview
Close-in grinding work in a tight spot is the situation this straight-line pencil grinder is built for. A turbine air motor spins a small collet, and the exhaust leaves from the rear of the body.
A turbine pencil format puts very high speed into a slim, light body, which is the reason to consider it for detail grinding. The limitation is that it needs compressed air, and the horsepower is stated inconsistently.
Who it's for
Shop users with an air line who need a slim, high-speed tool for fine detail work have a clear match. Someone who needs heavy stock removal or a corded or battery tool should look elsewhere.
Pros and cons
- Turbine air motor
- Rear exhaust directs air away
- Slim pencil body
- Lifetime warranty with registration
- Needs compressed air
- Horsepower stated inconsistently
- Air consumption not listed
Performance notes
A turbine air motor reaches its top speed only with a sufficient supply, so the compressor and hose set the real result. The small collet limits the shank size. Exhaust leaves from the rear, away from the work and the operator's grip.
Specifications
| Brand | Dynabrade |
|---|---|
| Model | 51703 |
| Dimensions & fit | |
| Collet | 1/8 inch |
| Item weight | 12.64 ounces |
| Capacity & performance | |
| Maximum Rotational Speed | 50000 rpmhigher than 96% of 95 power grinders |
| Power & efficiency | |
| Power Source | Pneumatic |
| Horsepower | 1 hp (title says .1 hp) |
| Construction & materials | |
| Color | Multi |
| Material Type | Metal |
| Included components | |
| Included Components | Dynabrade Branded Product |
| Unit Count | 1 Count |
| Warranty & support | |
| Manufacturer Warranty Description | Lifetime warranty, tool must be registered at Dynabrade.com |
| Other details | |
| Style Name | Pencil |
| Air inlet | 1/4 inch NPT |
Closest rivals on specs
Astro Pneumatic 218 Pencil Die Grinder 1/8 Inch- Maximum Rotational Speed 50000 vs 56000 rpm (-11%)
Frequently asked questions
Is the Dynabrade 51703 an electric grinder?
No. The power source is pneumatic, driven by a turbine air motor, so it needs compressed air at a 1/4 inch NPT inlet.
Does the Dynabrade pencil grinder pull a vacuum?
No. The highlight line lists it as non-vacuum, with rear exhaust.
What is the warranty on the Dynabrade 51703?
All tools must be registered at the manufacturer website to qualify for the lifetime warranty.
How much horsepower does the 51703 have?
The title says .1 hp and the spec table says 1 hp. The listing does not settle it.