Sanding circles on an edge sander (and some other edge sander techniques)

[Carlos Alvarez]

I recently picked up an older Jet edge sander. Before that I'd used some very small belt sanders, never something of this caliber. The belt runs pretty fast. Yesterday I was smoothing out a plywood circle I'd just cut, and managed to shoot it across the shop with great force. I was holding it down with a finger and spinning it around, and I let my finger go past the center which momentarily "locked" it against the belt. Took off out of there like a rifle shot. Is there a safe way to deal with circles on the edge sander?

I've also had some heating issues, particularly with wenge. It will definitely burn. I mostly work with exotics like that, and don't know if they are just too problematic to sand with something that moves this fast. Since I've only had it a little over a week, I've only used it a few times, so technique is definitely a likely issue.

It came with a few 80 grit belts and I just picked up some others (50, 100, 120). I have only used the 80 so far.

[Matt Day]

Carlos,
Sounds like you have learned to respect the sander a bit more now. Holding it down with a finger isn’t a good idea as you found out. Make a jig or something next time.

[Carlos Alvarez]

Well that's my question; what to use/do. "Make a jig" doesn't really tell me what to make. Or is it reasonable to just use a stop and hold the circle against both the stop and the belt? Just have no idea.

[Phillip Gregory]

I recently picked up an older Jet edge sander. Before that I'd used some very small belt sanders, never something of this caliber. The belt runs pretty fast. Yesterday I was smoothing out a plywood circle I'd just cut, and managed to shoot it across the shop with great force. I was holding it down with a finger and spinning it around, and I let my finger go past the center which momentarily "locked" it against the belt. Took off out of there like a rifle shot. Is there a safe way to deal with circles on the edge sander?

I've also had some heating issues, particularly with wenge. It will definitely burn. I mostly work with exotics like that, and don't know if they are just too problematic to sand with something that moves this fast. Since I've only had it a little over a week, I've only used it a few times, so technique is definitely a likely issue.

It came with a few 80 grit belts and I just picked up some others (50, 100, 120). I have only used the 80 so far.

A disc sander is ideal for sanding circles. The direction of the sanding medium is down into the table, assuming you are using it properly and only using the half of the disc that is rotating downwards towards the table. You will never throw a piece of stock using that machine in that manner. You can also vary the aggressiveness of the sanding by moving laterally, the closer you are to the edge of the disc, the more aggressive the sanding, and the closer you are to the center, the less aggressive as the surface feet per minute of the sanding disc is slower near the middle vs. the outside as the circumference near the middle is much smaller but the RPM of the disc is constant. The larger the diameter of the disc, the larger the difference in aggressiveness between the outer edge and the center. I recommend if you are sanding circles on a recurrent basis that you get a 20" or better disc sander.

An edge sander has a constant speed of the abrasive medium over the entire surface area of the abrasive. You can catch and throw a piece of stock if you are not holding on carefully, which is why most have some sort of a stop near the end the belt in the direction of travel. If there isn't one, you can clamp a piece of wood as a fence there to rest your stock on.

Changing the belt speed is quite difficult with a typical direct drive unit unless you have a sander with a 3 phase motor, in which case use a VFD and you can vary between 50-100% of rated speed without any issues.

Burning with a sander is due to taking too heavy of a cut with too fine of an abrasive. There is too much friction, which makes heat and results in burns. Use the 50 grit belt and you will see less (and perhaps no) burning. Changing the belt on a decent edge sander isn't hard so try the 50, take your heavy cut, and then change to the finer belts to just kiss the stock for a finer finish if needed, and you will see better results. You might even look to a 30 or 36 grit belt if you are taking very heavy cuts at first.

[glenn bradley]

Well that's my question; what to use/do. "Make a jig" doesn't really tell me what to make. Or is it reasonable to just use a stop and hold the circle against both the stop and the belt? Just have no idea.

You will get used to the faster speed. If I could cut my Jet's speed by half, I would. Controlling burn on a fast machine for me is unfortunately a matter of grit. I have to use coarser grits than I actually want and finish the process in another way. I just couldn't bring myself to spend the coin that a higher end machine cost so now I deal with it via technique.

As to circle jigs, shop made designs abound in magazines like Woodsmith or Fine Woodworking as well as online. Essentially you need a platform that can secure to the machine, an adjustable pivot pin in line with the point of contact and you are pretty much there.

A circle jig for a bandsaw can also work for the router table and the edge sander if you factor those things in when you are designing it. Mine attaches to the miter slot, is supported by a roller stand and uses a t-track for the adjustable pivot point.

b-BS Circ Jig v2 stop.jpgc-BS Circ Jig v2 lock-1.jpgf-BS Circ Jig v2 o-view.jpge-BS Circ Jig v2 rear-supp.jpgap-Ped-Tbl-Top-circ-jig-rt.jpgNiki CT Dresser (99).jpg

[Mike Hollingsworth]

Well that's my question; what to use/do. "Make a jig" doesn't really tell me what to make. Or is it reasonable to just use a stop and hold the circle against both the stop and the belt? Just have no idea.

This is the way to go.
I guarantee you've got some skinned fingertips coming your way.

[Carlos Alvarez]

Ok, so a stop would be easy to make and slip into the slot. And I made a circle jig for the bandsaw, used it for this, and never thought to see if it fits on the sander. Duh. Also I thought 80 was already extremely coarse, guess I'll see what the 50 does.

I don't make/use a lot of circles, so another sander isn't really warranted.

[John K Jordan]

A disc sander is ideal for sanding circles. ... I recommend if you are sanding circles on a recurrent basis that you get a 20" or better disc sander.
...

That's what I use to sand circles and arcs. I have a 10" disk and it works OK but if I did this a lot I agree, a larger disk would be better.

[Jerry Wright]

The HF 12" disk sander is an inexpensive addition and very useful. The main machine is built well, the table is a bit flimsy, but does the job if care is used. It isn't a Powermatic, but we'll worth the low cost.

[John Sincerbeaux]

A disc sander is the correct machine for most curved shapes. Think about grain orientation. Edge sanders are for sanding parallel grain edges like doors faceframes, boxes etc.
The burning issue sounds more like an oscillation issue? Does your sander oscillate? If not, you can make a “false” table that is diagonal to the belt so you can move the workpiece up and down the surface of the belt. My edge sander oscillates and i have never used a belt that is less tn 180 grit. Mostly just 220 grit.

[glenn bradley]

"Correct" is a strong word ;-) Depending on the stock it is cut from, the amount of edge grain can vary. Vertical sanding marks from a disc sander can be tedious to get out of edge grain if you don't want them. Different tools for the same job varying with the material being treated. That being said, I often rough out end grain curves on the disc sander which excels at this task. For sweeping curves like chair rockers, an edge sander (outside) and a spindle sander (inside) are my preferred machines.

[Robert Engel]

Carlos,

I do agree re: disc sander but I can be done safely with a jig.

How about double back tape to a lazy susan type jig? Or if one side could have a registration hole, a jig with a pin.

You could make the jig slide on a base that is clamped to the table.

Be careful a belt sander will also sand flesh!!

[John Sincerbeaux]

"Correct" is a strong word ;-) Depending on the stock it is cut from, the amount of edge grain can vary. Vertical sanding marks from a disc sander can be tedious to get out of edge grain if you don't want them. Different tools for the same job varying with the material being treated. That being said, I often rough out end grain curves on the disc sander which excels at this task. For sweeping curves like chair rockers, an edge sander (outside) and a spindle sander (inside) are my preferred machines.

””Correct” is a strong word”
So are the words “shoot it across the floor with GREAT FORCE” and “like a riffle shot”.... from the OP’s original post.