Thursday, August 27, 2009

Slab roller retrofit - part three

Turns out that mounting the motor to the shelf of my slab roller turned into a much bigger job than I anticipated. The motor itself has four threaded mounting holes.

So it was easy to lay out the hole spacing on a piece of Baltic Birch plywood, and drill the holes.

Of course, I had to countersink the screw heads, so that the plywood would sit flush on the shelf.

Even with that huge assortment of screws that I had, I still didn't have four matching ones. So off I went to the local hardware store.

Of course, once I got to the store, I couldn't remember the length I needed, so I bought a few different sizes, just to be sure.

With the right hardware, this part was easy.

And I'm so fussy, of course I had to align all the screw slots.

Here's the motor mounted to the plywood, awaiting the next step - mounting the pulleys.

On the rollers, there is a 5/8" arbor, where I'll mount the top pulley. But first, I had to knock this pin out.

So I grabbed my "go-to" baby ball peen hammer. It doesn't look that small, but here it is, next to a normal sized one.

Then I grabbed a punch, to knock the pin all the way out.

And then mounted the pulley with a set screw.

With a level, I tried to roughly align everything.

Before I could mount the lower pulley to the motor, I realized I needed a piece of keystock for the motor shaft.

Luckily, I had a long piece of it sitting in a drawer.

So I put it in a vice and cut off a small piece of it.

Then filed off the rough edges.

With a little bit of coaxing, the pulley was mounted to the motor shaft.

The next part was easy - place the motor on the shelf below, and slip the belt onto both pulleys.

The only problem - the belt was a little long, making it way too loose on the pulleys.

Do you think I could wait until I had the right sized belt? Hells no,
I clamped the motor/plywood down and flipped the switch on for the motor.

And I have to say - watching that motor slowly turn the rollers was a moment of sheer joy. My buddy Dave, the designer of this system, not only included a speed control for this motor control, but he made the motor reversible. It's an incredibly sweet system.

But because the belt was so loose, I didn't try running any clay through the rollers.

Next step - either lowering the shelf to make the belt tighter. Or buying a smaller belt. Hopefully, my next (and final) post about this slab roller retrofit will include a short video to show how great this works.

Stay tuned...

Friday, August 21, 2009

Pretty interesting video

The third installment of how I added a motor to my slab roller is coming, but I haven't quite finished everything yet. Meanwhile, here's a pretty fascinating video showing how a trailer is built, thanks to some time elapsed videography


Tuesday, August 18, 2009

Motorizing a slab roller, part two

When I ended Part One of how I added a motor to my slab roller, I'd just finished adding a shelf to the legs, thus giving myself a place to mount the motor.

Even though the motor that will drive the slab roller looks wimpy, it's not.

I decided mounting the motor control box would be my first task. It's location is important, and I didn't want it to be in an inconvenient location.

Looking at the end of the slab roller, it made sense to use some of the same bolts that were used to connect the legs to the apron. That metal is fairly beefy, and I didn't feel like drilling new holes, if I didn't need to. So I removed a couple of the bolts on each leg.

After a little measuring to determine the size for a piece of plywood, I propped the control box up against the plywood, to make sure I'd done everything correctly.

Of course, I couldn't use the old bolts that I'd removed from each leg, they were now too short, with the addition of the plywood. So I went over to my "bolt drawer".

Doesn't every one have one of those?

OK, it's a big mess. (I knew you were thinking that.) But it had exactly what I was looking for - longer bolts.

Then I drilled some holes for mounting the box to the plywood. Don't pay any attention to that dried blood on the handle of my drill. That's from a while ago.

Everything was going according to plan, I bolted the plywood in place, and then hit my first snag.

The location of the holes meant I needed to drill some new holes in the legs.

But remember that I mentioned those legs were made of heavy gauge of metal? I had to drill holes in the metal when mounting that shelf, and it wasn't any fun. In fact, it was probably the worst part of that whole task. So I put on my thinking cap and decided I'd add a couple spacers behind the plywood, so that the bolts wouldn't have to go through the legs.

Spacers? No problem... just a short walk over to the "Washer" drawer.

Pure washer heaven.

A couple of spacers later, and the control box is mounted. It's location is perfect.

It really went together quite easily.

Well, sort of. I scratched the crap out of my arm while reaching for something.

Considering how hot it was in my studio, I thought this would be a good time to quit for the day.

Oh, what was I thinking? I can't stop in the middle of something like this. So I started examining the motor, to figure out how to mount it.

Dave was kind enough to put a warning label on the plug that CANNOT be plugged into a regular wall outlet. And he left me a note that said I could mount the motor in one of two ways. I chose the four holes on the bottom.

Bolts, anyone? I'm the queen of bolts.

A couple of measurements, to determine the size of the plywood I'll need to cut.

A little more measuring, which brings up a pet peeve. Notice the tape measure, and how it reads upside-down?

That's why I bought several of these from Lee Valley, made for right-handers like me.

Isn't 93% of the world right-handed? Can anyone tell me why ALL tape measures don't read like the Lee Valley tape measure?

Just as I was ready to start mounting the motor to a piece of plywood, I realized I was running out of time. I have a class to teach in a few hours, and I need to clean up and print off a few hand-outs.

Stay tuned, the next step will be interesting....

Saturday, August 15, 2009

Summertime grilling

Don't you just love grilling in the summertime?

Thursday, August 13, 2009

Motorizing a slab roller, part one

It started with a Northstar slab roller.

Well, no, I take it back, it started with a backache.

See, I have a bad back. Too many years of hard labor, added to the fact that I'm only five feet tall. OK, a little taller in work boots. Still, lifting sheets of plywood, or flipping an armoire on it's side has taken it's toll on my spine.

When I roll out slabs of clay to make tile, it hurts. Not right then; it hurts the next day, or two, or seven. So working with clay has gotten more and more difficult over the years. I needed a better way.

Now I'm lucky. I have some friends that are MUCH smarter than me, and I turn to them when I'm having one of those "how the hell do I do this?" moments. So last year, when I was suffering from a horrible backache, I asked my buddy Dave, who by the way, is a genius, to help me figure out how to motorize my slab roller.

I'm not making it up about Dave being a genius. He is. And even better, he's a motion control expert. He's worked for years in the field of automation, and is the go-to guy if you're looking to automate something within your business.

So the first thing Dave suggested was pulling off the huge crank wheel, so see what we had to work with.

Simple enough, there was a 5/8" shaft.

Now have you ever met someone who is so smart, they can calculate things in their head in seconds, when it would have taken you hours to do all the calculations? So giving Dave some rough dimensions of the space I had to work with was all he needed.

First thing he had me do was add a shelf underneath, so I would have a place to bolt down a motor. The height wasn't entirely critical, but I knew I was going to need about 16" between that pulley and the one I would mount below. So I measured accordingly, and started building my shelf. Here are the 2x4's on the each end.

Then I added some cross pieces, to beef it up.

Lag bolts hold the legs together. I forgot to mention that almost all of this material was stuff I had laying around the woodshop. So I walked over to my "lag drawer" and looked for some appropriate sizes.

Yes, that's an old library card catalog. Excellent for storing stuff in the woodshop.


Well, not so fast. There wasn't a
way to get a plywood shelf in place without removing one of the legs.

So off came the leg. (I had to prop up the slab roller with a shop cart, to keep it from tipping over while the leg was off.)

And on went the shelf.

With the leg back in place, the first part of this retrofit is starting to shape up.

Another buddy of mine had donated a small motor to this project, so just for the heck of it, I hooked it up.

With some luck, I realized I'd put that mounting shelf in the perfect place for the motor belt that I'd purchased. (What's that line about even a broken clock being right twice a day?)

So.. it all looks pretty great, right?

Well, not really.

The first time I plugged in the motor and fed a piece of clay through the rollers, I ended up with a huge splat of clay on the wall, ten feet away.

Back to the drawing board.

Which brings me back to Dave. A couple of phone calls and a little begging, and ... well... stay tuned for part two.