How well would this work?

[juicaj1]

I had an interesting idea a couple days ago. I don't have a belt sander or grinding wheel or anything like that but I figured I will probably need one. I was thinking of trying to do something cheaper than buying a new or used grinder and came up with the idea to use some dated technological ideas. Basically what it would be is a wheel with belt sander sandpaper or something like it on an upside down bicycle. It would all be modified so it could stand and be pretty sturdy and I would sit down and pedal to spin the wheel. Does this sound like a decent idea or would I just be better off buying something?

[monstermetal]

I think it could have merit... You could build a reasonably effective power source from a bicycle... the issue is that much of what you want to do at a belt grinder is precision work thats hard enough to do standing dead still with both feet on the ground... Trying to do it while pumping away at pedals fast enough to make the grinder work would make it much harder...
Nothing wrong with building a grinder though.... A motor can be bought cheap... Ive bought several for less than $20....

[Scampbell]

Look at the early sharpening wheels.... Very similar to what you want to do but uses your feet to do the pumping kinda like the old singer sewing machines.... Or look for yard sale/ swap meet/ harbor freight for sander they probably can be had for less the cost and time of your "project" believe me, I always think of a differant (cheaper) way to do things ...most of the time when I figure time spent on the project and cost it is usually cheaper to buy the rite tool. My .02

[NN4N]

I agree with monstermetal that it is possible but probably very hard to pedal and keep a steady hand while grinding.

Another thing to keep in mind that you'll need a heavy flywheel in order for this to work. If you look at these types of grinders they used in the old day (google for sharpening wheel) you can see that its a large solid stone wheel. A large heavy wheel has a large moment of inertia, which allows it to basically store rotational energy. Therefore it won't stop as soon as you touch your metal to the wheel.

If you get a decent wheel and a motor you can probably use the bearings and the chains from a bicycle as a starting point. But as mentioned by Scampbell, it'll probably take quite a bit of time and money, probably more expensive than buying something suitable.

Just my thoughts,

NN4N

[Francis Trez Cole]

Here is a link to a system that is simple just need a motor they work great this is just one company there are a lot of different sizes out there
http://www.caswellpl...fs/expander.htm

[Don A]

Here's a link to an old thread with a cool picture of a bike grinder that Dana Aker made:

http://forums.dfoggknives.com - Aker grinder

You should be able to adapt the engineering to some sort of belt.

However, 1750 rpm might be a challenge! Better still, you could build it for someone else to pedal while you do the grinding.

[David Einhorn]

You also might wish to look at a reprint of this 1941 book that shows the construction of a sander-grinder out of short lengths of pipe.

Book titled, “40 Power Tools You Can Make (Woodworking Classics Revisited)” [Paperback]
“Originally published by Popular Mechanics in 1941, this classic manual is a testament to the ingenuity and dedication of American craftsmen. The collected projects, written by various craftsmen, demonstrate how to build a 10-inch thickness planer, a “swing saw” (or cut-off saw), and a hand-built hydraulic press, in addition to drill presses, jigsaws, sanders, bending brakes, band saws, a wood lathe, and many other useful machines. All of these machines are built with simple and highly available materials, and every project is accompanied by the original instructions, illustrations, and measured drawings. In addition, this vintage reprint offers its readers a unique look into a period in American history—when materials and labor were stretched thin, and American craftsmen were forced to “bootstrap” solutions out of the bare essentials available to them.”
• Paperback: 96 pages
• Publisher: Linden Publishing; Reprint edition (December 1, 2008)
• Language: English
• ISBN-10: 9781933502205
• ISBN-13: 978-1933502205
• ASIN: 1933502207

[Marksnagel]

It would work well for you if you had someone other than the person holding the piece to be sanded do the pedaling.
I agree that a motor would be the best bet though.

Keep thinking outside the box though. Necessity is the mother of invention, or something like that.

Mark <><

[juicaj1]

That guys bike grinding wheel looks awesome. Yeah I might just end up buying something cheap off of craigslist or at a garage sale. I'm sure my dad wouln't be very thrilled if I brought home an old bike and said I was going to make a grinding wheel.