How to make a homemade 2x72 belt sander or belt grinder
This is an in-depth overview of how to make a belt sander. It includes numerous reviews of articles on building a belt sander, forum discussions (including our HomemadeTools.net forum and others), and videos on building a DIY belt grinder or a DIY belt sander. Eight of these builds include detailed homemade belt sander plans.
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Table of Contents
We'll focus mostly on 2x72 belt sanders. However, we do have a handful of mentions of small strip sanders, handheld belt sander conversions, and home built belt sanders with belts shorter than 72". We'll also discuss sourcing used motors, building your own homemade belt grinder wheels, and a variety of other techniques for saving money while you make your own belt sander.
A high-quality new 2x72 belt grinder costs over $2,000, even if constructed from a belt grinder kit. Some home builders make their home made sanders for next to nothing, while others purchase new wheels, a new motor, and other goodies that can quickly push the cost over $500. However, a good homebuilt 2x72 belt sander can reasonably be had for 1/10th of the retail price - around $250. If you can inexpensively source some spare parts and components (most namely the motor), that cost can easily be cut in half, to around $125.
All of the builds featured herein are fully credited to the original builders, and link to each respective build page or video. We've done our best to contact everyone mentioned here, but if you see your build in here - congratulations, you're internet famous :). If you have a belt sander build that you'd like us to add, post about it on our homemade tools forum.
A belt sander can be reasonably broken down into the five constituent components listed below. If you want to build a belt sander, but you don't know where to start, consider each component separately.
1. The frame. This will usually be steel, but can also be wood. The metal frame will usually be welded together, but you can bolt it together too. A great trick is to get a free weight bench on Craigslist, and cut it up to use as a frame.
2. The wheels. You can purchase pre-made belt sander wheels from Beaumont Metal Works, although they're fairly expensive. If you have machining skills, you can machine your own wheels. You can source wheels (skateboard wheels are a favorite). You can also build your own wheels from wood, or multiple layers of MDF. Idler wheels can be pulled off of engines. Wheels will need to be crowned for correct tracking. Crowning can be machined, or even done with masking tape. However, the crowning can be worn down by the backing on the 2x72 belts.
3. The power source. This will almost always be an electric motor. You can buy a brand-new motor. To save money, you can remove a motor from an existing tool or appliance.
A favorite trick is get a free treadmill from Craigslist, with a nice motor plus controls that will allow you to vary the speed of your belt sander. To get a rough idea of the treadmill motor's condition, examine the treadmill belt, and see how worn the more common buttons or controls are. A treadmill motor will usually be in excellent shape; you're probably not going to be getting a well-used treadmill from an Olympic athlete. When sourcing from Craigslist, consider searching with misspellings; in this case, your most common misspelling of treadmill is going to be "treadmil". Also, it's occasionally spelled as two words: "tread mill".
Here are some videos on identifying and wiring treadmill motors for use in homemade tools.
How to wire DC motors, universal motors, and treadmill motors. Includes details on incorporating speed controllers. By Jeremy Fielding.
Treadmill motor wiring with off-the-shelf parts. By buffcleb.
DC treadmill motor controller wiring for a belt grinder. By mikemanmade.
You can also convert an existing tool into a belt sander; a bench grinder is a favorite for this. Smaller belt sanders can be driven by an electric drill, or even a rotary tool like a Dremel.
A sealed motor will provide protection from dust and debris. You can also build your own protective housing. You won't really know how bad the vibration is until you first use the sander. For now, just consider mounting options that minimize vibration.
You may want to adjust motor speed, and one nice method for accomplishing that is a step pulley. Some builders find that, after accounting for speed adjustments, either with a variable frequency drive, a step pulley, or some other method, they rarely use the different speeds anyway.
4. The tracking mechanism. The belt needs to be properly tracked so that it rides correctly on the wheels. For many first-time belt sander builders, this is an afterthought that turns into a huge headache when the belt sander is first tested. Fortunately, tracking is fairly easy, and is usually achieved with an eye bolt. Tracking generally needs to be adjusted when speed is altered.
5. The tensioning mechanism. The belt on the belt sander will need to be tensioned to operate, and then relaxed to remove the belt. One trick is to mount the motor to a hinged plate, which is then used as the tensioning device. Another great technique is to salvage the incline motor from a treadmill, which is used to vary the treadmill incline so that a person can walk or run "uphill" on the treadmill. This incline motor can be used as a tensioning motor.
In addition to the above five components, there are various add-ons that you can consider down the line, including:
-Grinding rests of various types.
-Disc sander or buffing wheel add-ons.
-Wheels or casters for portability (one trick is to use an inexpensive Harbor Freight rolling engine stand).
-Bin for gathering sparks.
Once the belt sander is built, these add-ons will be fairly easy to construct and customize for your use. It usually makes more sense to build your belt sander, get it running, and then customize it as you see fit. Most homemade tool builders never completely finalize a build; they like to add to it and adjust it over time. Your belt sander will probably never be completely finished - you're making a tool, not a sandwich.
Here's our curated selection of articles and forum discussions of standard belt sander builds (videos, plans, and miscellaneous other belt sander builds are further below). Click on each photo below for the full build.
Made from metal plate, with scrap aluminum for the rollers and pulley. By Vyacheslav.Nevolya.
Made from scrap metal and a 2800 rpm motor. By rendoman.
2x72 with stand, 1/2 HP motor, and wheels from eBay. By chiasson.
Tiltable sander with metal tubing frame and MDF wheels. By Roger Xue.
Detailed build with multiple photos and videos. Switches between vertical and horizontal operation; built with CNC machining. By HelicopterJohn.
Commercial-quality build of belt grinder for knife making. Includes many 3D renderings. By Vladislav.
Beautiful high-end belt sander. By Vernon.
2x60 knife grinder. Made out of aluminum, with plywood idler wheels, for under $200. By Dave Wood.
Small 1x30 strip sander made from plywood. Many photos, build details, and video. By Dave Wirth.
Here's our curated selection of videos of belt sander builds.
YouTube videos are best watched with speed controls in mind. For many builds, we recommend first watching the build at 1.5x or 2x speed. You can easily adjust this on YouTube via the cog menu at the lower-right-hand side of any video. On the other hand, you may want to watch a part of a video in slow-motion. To do this, pause the video, then advance frame-by-frame using the period key to go one frame forward, and the comma key to go one frame back. You can also use the L key to skip forward 10 seconds, and the J key to move backward 10 seconds.
There are actually hundreds of YouTube videos on building belt sanders; you could watch them for weeks. We culled out the ones with bad lighting or audio, and we focused on shorter videos. Some of the better videos that we included are indeed longer (20+ minutes), or are part of a series of related videos. You can also use the 2x speed trick mentioned above to reduce a half-hour video to a manageable 15 minutes.
2x72 sander built from treadmill and weightlifting bench. By mikemanmade.
2x72 sander made from square tube and plate. Includes turned pulleys from cast aluminum stock. By Black Beard Projects.
2x72 sander build that documents construction process. Used a tractor to stretch out an extension spring into a compression spring. By Making Stuff.
5 short related videos. Made from scrap metal, including trailer hitch. By alaskabearhawk.
$50 2x72 sander built from free 2HP treadmill motor, incline motor for belt tensioning, and removable tool rest. By ryanjerby25.
Inexpensive wood grinder based on a bench grinder. Makes clever use of skateboard wheels and trucks as belt sander wheels and tracking mechanism. By Eternal Knives.
Belt grinder/disc sander combo with vertically adjustable stand and basic eyebolt tracking mechanism. By Dan Fuller.
1x30/1x42 sander is mounted to an X-Y vise for tracking and changing belts. By Lewis Razors.
Basic belt grinder build with simple tracking adjustment and step pulleys. By dukhunter20.
Motor from air compressor, framework from thick industrial shelving, and includes funnel catch basin for catching debris. By towerhillbilly.
Grinder made from Harbor Freight lathe. By Chandler Dickinson.
Lowbuck wood frame grinder. Drive wheel made from deck boards with a crown filed in, plus skateboard wheels and trucks. By Mark Thomas.
Grinder that switches easily from horizontal orientation, to a vertical belt sander. By Alan Alboa.
Details on mounting a belt sander to a table. By Paoson WoodWorking.
6x48 wooden build. Interesting method of rounding the rollers by spinning them over a table saw. By Matthias Wandel.
Here's our curated selection of belt sander builds that include plans. Click on each photo below for the full build.
Adjustable height sander with wheels purchased from Beaumont Metal Works. By Ken Reed.
Comprehensive build with bill of materials, photos, and construction tips. By Michael Clerc.
Sander with used motor and VFD. Includes plans for belt sander, and separate plans for machining wheels. By Dan Comeau.
Includes detailed CAD plans, and incorporates tracking, drive, and idler wheels sold on website. By Chris Williams.
30"/48" sander with turned aluminum pulleys and tilting table. Includes many technical drawings. By digr.
2x72 sander powered by a 2HP motor with speed control. Includes technical drawings. By Mike Conner.
Includes basic bill of materials, instructions, and photographs. Plans available by email. By Jonathan DeVries.
Simple smaller sander with plywood frame and commercial wheels. Includes 1 basic technical drawing. By Robert Frink.
The easiest way to build a benchtop belt sander is to solidly mount a portable belt sander. This won't be a DIY 2x72 belt grinder, but the cost is minimal, sometimes even free. Firmly mounting a portable tool for use as a fixed tool is a well-used trick of the homemade tool builder, and applies to many different tools. Here are some examples of builds that feature mounted portable belt sanders. Click on each photo below for the full build.
A basic workbench mount for a portable belt sander. By 1dmaxpwr.
Clamping a portable belt sander in a vise. By Boyntonstu.
A simple wooden jig for benchtop mounting of a portable belt sander. By Sandor Nagyszalanczy.
Wooden box mount for an antique Rockwell handheld belt sander. By BrooklynBay.
A hand drill/driver or a rotary Dremel tool will never be powerful enough for a 2x72 belt grinder. Nevertheless, powering a belt sander with these tools is clever, and worth mentioning, albeit briefly. Here are some examples of drill-powered and Dremel-powered belt sanders. Click on each photo below for the full build.
Dremel belt sander attachment. By Tuomas.
Portable, Dremel-powered mini belt grinder. By barberorp.
Drill-powered strip sander from plywood. Shows entire build process, plus measurements of all components. By Gökmen ALTUNTAŞ.
Yet another strategy is to construct a belt sander from a bench grinder. Here are some examples of belt sanders made from bench grinders. Click on each photo below for the full build.
Twin belt sander, powered by bench grinder, with frames cast in aluminum. By Carlos B.
Twin belt sander based on bench grinder. By garycullen.
A basic belt sander made from a bench grinder, with machined pulleys. By naughtyboy.
You can find all manner of homemade tools on the Homemade Tools Forum, but forums specific to knifemaking are also great resources for homemade belt grinder builds. Here's a list of forums with information on making your own belt grinder.