Introduction: Minimalist Bench Sander
It was time to change the belt on my sander. While I was at it, I decided to pimp it up. Here's my minimalist approach to attaching a solid, square fence to a portable belt sander.
Step 1: Portable Belt Sander
I bought this sander a few years ago from Harbor Freight. There was a dizzying array of models to choose from. This one had an adjustable handle. When laid flat, the sander can be laid on its back, and it's quite stable. I figured I would convert it into a bench sander, and this feature would save me some work. Even if your belt sander does not stand on its own, this instructable may still help you to attach the all-important fence. See, the fence must be square to the belt if you want to create and/or retain nice, square edges.
Step 2: First Attempt
This was my first attempt at attaching a fence. It worked good enough. I used it for three years, and it got the job done. But there were a couple of annoyances with it. As I used it, it "broke in" and the fence tilted. Once it finally settled in, I resanded the face of the fence straight again. That's the most important bit. But the top surface of the fence was no longer in a parallel plane with the belt. This plays tricks on your eyes when you're trying to sand stuff. So I decided to do it again, and to do it better.
Step 3: Basic Problem
The essence of this project is to get the fence to be secure and square. So here's what we're looking at. The belt rides over a flat metal plate. I want the fence to be as close the the back edge of that plate as possible, and still be secure. There's not much there to support the fence. At first glance, this looks like mission impossible. But with the help of physics and some shimwork, it is not as daunting as it may at first seem. All we need to do is support the fence at the four corners, leveling it with shims.
Step 4: Making the Shims
The fence is going to be a 1.5" tall square block of wood. I want it to be exactly square and in parallel with the surface of the belt. In my estimation, the easiest way to do that is to make some shims. Afterall, a belt sander is a great tool for fine-tuning shims in no time flat! See the pics for the play-by-play.
Step 5: Attaching the Fence
Now to attach the fence, it doesn't take much strength at all. I use just two thin strips of wood to screw the block to the housing. The way the block is attached, it will only push back and down when ur using it. Since the shims keep the block square when you push down on it, I just need two little strips attached in such a way to prevent the block from going back!
Step 6: "Spindle Sander"
Before I put it back together, I decided to cut away part of the front housing. This exposed the front roller, allowing some sanding ability on concave surfaces.
Step 7: Done!
Doing this "correctly" turned out to be much easier than I would have thought. This fence is very stable, very square, and I foresee it being in use for many years to come.
7 Comments
9 years ago on Introduction
She's magic. Wherever she goes, things get clean and organized. You can see a better picture in my "My Workbench" Instructable.
Reply 9 years ago on Introduction
She's been on my outdoor bench for awhile. Here's the before and after. :)
9 years ago on Introduction
Oh, I have a terrible image of friction and dust setting that block on fire...
Reply 9 years ago on Introduction
I'm not too keen on the use of wood for this project either. I tried to use wood for a table on a disc sander build and that was horrible. The table shook, and vibrated a lot and I just didn't use the machine because it was generally unsatisfactory to me. So I took the time to rebuild it using metal and now I am completely happy with it, and use it all of the time too. Sure it was a lot more work but I'll have it for the rest of my life.
The moral of the story is sometimes it is worth making the extra effort. I wish I had a picture of the old disc sander because it didn't look too bad, it just worked bad. Here is the rebuilt machine. There is a 2x12 wooden spacer block in the base but that does not seem to hurt rigidity.
Reply 9 years ago on Introduction
Nice work on your disc sander, BTW. It looks extremely efficient in terms of space and weight and use of materials.
Reply 9 years ago on Introduction
It all depends on how you use it. Wood has a good modulus of elasticity-to weight ratio. It's higher than cast iron. So unless you're willing to use a substantial chunk of metal, you still won't be any better than using the solid block of white oak that I used.
If vibration was an issue for your sander, I wonder if your disc may need some balancing. There's no reason you cannot build a proper disc sander table out of wood.
Say my fence was made of solid steel. 5 pounds of it! And instead of shimming it, I drilled and tapped the four corners to take leveling screws. Then I cut some nice brackets for securing it. Well, this solid metal fence is still being supported by the plastic housing of the belt sander. That's the limiting factor, here, not the fence. So all that effort is for naught unless I take apart the sander and rebuild the housing to also be more ridged (and larger and heavier). It that's what I wanted, I would have bought a bench sander. :)
A proper disc sander is at the top of my want list. But I have a small outdoor work area, and the only spot that is protected from the rain is already occupied by more essential tools. I use this little sander because it has a small footprint. It's light. It will be easy to transport when I eventually move into a place with more space. And I also very occasionally use it as a portable belt sander. So perhaps it's not a matter of "extra effort" so much as I'm not you. Our situations are different.
Reply 9 years ago on Introduction
Thanks. Safety is always important. The thought touched my mind that heat could be an issue. Before cutting out extra relief, I just went ahead and watched what happened. Nothing bad. My first belt lasted for 3 years. (Quality belt - I threw the original in the garbage before I even turned it on.) I've never seen a hint of sawdust collect at the bottom of the fence. And in the pics you can see the original fence wasn't scorched on the bottom.