So… Let’s say it’s Sunday afternoon in late October. You’ve just spent two days cleaning up your American Sawmill Machinery 30″ bandsaw. The whole machine is back together and looking very smart.
But wait… Where is the upper guide block? You tear through the entire shop trying to figure out where you squirelled the damn thing away. After an hour of searching, no luck. Now what?
Let’s look at how much a replacement block will cost… $300+ for one block?!? No way. That’s more than the saw cost. So, you start thinking… (this is where things go right down hill). You look at the Carter guides on the Yates American 30″ bandsaw. They are made of cheap pot metal. This stuff is extremely brittle and weak. One of the mounting screws was over-tightened at some point, causing the body to crack. I’ve always dis-liked these things. Everyone I’ve ever seen was broken or had a big chunk out of it.
Surely there must be a better design.
Back to the computer.
The first promising prospect was the Paddock # 20. It has a grooved thrust bearing at the back and a set of bearings in place of the standard guide blocks. The body is cast aluminum. I’ve seen these before and always assumed that they were antique. In reality, they are still in production today (just using the original design/pattern).
Price: $265 for the number 10. I assume the number 20 is substantially more. Definitely a better value than the Carter, but still a lot of money for a set of guides.
Then there are the Wright guides. These are the same style as the Carter guides, but the body is also cast iron rather than carboloy. These guides feature two sets of guide blocks (one above and one below the bearing).
Nice.
Good sturdy assembly. Spare parts are readily available.
Price: $289 for the number 2. Definitely the best value for the money.
Ok. So the Carter guides are out. It’s a toss-up between the Paddock and the Wright (I’d probably lean towards the Wright).
I should just order them, but I’m exceedingly cheap.
I can’t help but think that I should be able to come up with something better for less money.
Back out to the shop. I tear through all the bins and cabinets and piles of scrap metal and come up with a pile of parts:
The pile consists of three bearings, an old block of aluminum scrap, some hex screws, washers, nuts, plug screws and a piece of hardened pin stock.
As with most of these projects, the plan developed as I went along.
First, I wanted the double bearing guides, rather than the typical blocks. I also wanted a thrust bearing that didn’t cause too much friction.
After about an hour and a half of messing around on the old Toolmaster mill, I came up with this body:
You’re looking at the back/left side of the block.
The slot in the center is for the thrust bearing. The slot at the bottom is a recess for the nuts on the hex screws. The round hole bored at the top is for the mounting stud (threaded hole is for the hex plug screw that tightens against the mounting stud. The threaded hole at the center is for the hex plug screw that pushed the hardened pin stock against the center race of the bearing.
Some other views of the block below:
Right. It’s literally a block. Nothing pretty about it.
Now let’s put it together and see how it looks:
First an explanation of the mounting of the thrust bearing. I took a piece of hardened pin stock and ground it to fit into the center of the bearing. I left a slight shoulder on it so it would press aganst the center race. The bearing is placed in the slot with a washer to the left and the pin stock is pushed through. This is followed by the hex plug screw, which presses against the pin; locking the center race of the bearing against the washer and the shoulder of the pin.
Here’s an exploded view of the thrust bearing assembly:
A close-up of the pin. The thrust bearing is the wider of the three (left):
And, a number of views of the assembled guide unit:
Not bad, but will it work? The block is definitely sturdy.
To adjust for a wider blade, you just add two bearings and longer hex screws.
The bottom corners could be rounded off.
Next step is to test it on the saw.
Should be interesting.
Oh.. And now that I’ve spent all this time and effort on the replacement, you can bet that the missing guide will turn up out of nowhere.
Update: When I got home from work today I went out to the shop and mounted the new guides on the bandsaw. The short of it is that they fit and work great.
So, let’s summarize: The parts were basically free since they were just laying around the shop. It took about two hours of machine time (most of which was planning). I got a very sturdy set of guides with easily replaced components. Looks like success to me.
I’m already looking at improvements on the design. I think I can reduce the height of the block by 25% by moving the mounting stud lower. This means I’ll need to use a thicker piece of aluminum. A benefit of doing this is that I can use a much larger thrust bearing. This will also add some rigidity to the entire mechanism. This will very likely end up being a cast part. It looks like a pretty straightforward pattern and it’ll reduce the number of machine operations required to go from raw materials to a finished part.
Here are the drawings of the current vs. the improved design:
Bandsaw Guides
And finally, the video of the guides in operation can be seen here:
Tags: band saw, Bandsaw, Carter, Carter Guides, guides, owwm, Paddock, Paddock Guides, Toolmaster, Wright, Wright Guides
Wow. That Sucked.
Nov 10th, 2012 by The owwm
If you tried to visit this site recently, then you probably noticed that it went completely dark for an extended period (thirteen days to be exact). If you live in the northeast, then you know we had a hurricane come ashore here in New Jersey. That’s two years in a row that we’ve taken a direct hit. After the experience I had with hurricane Irene last year, I was better prepared. I had recently installed a 37 KW generator. This was a much better setup than the two small gensets I had last year. I also bought a backup sump pump and cleaned out the daylight drains in the days before the storm. Most of the damage we suffered in Irene was from water. With Sandy it was the wind. During the first few hours of the storm the lights started to flicker and brown out. By 9PM on Sunday evening, we completely lost power. I was concerned about the sumps, so I went to the basement and checked the pits. Both were pretty much dry. Next I went outside to check the daylight drains. These empty out about 800 feet from the house. The wind was blowing so hard that I had a tough time just walking across the front yard. There was alot of debris blowing through the air and I could see shingles and branches flying by. Every once in a while I would get hit by what felt like a tennis ball sized object.
Suprisingly, the drains were pretty dry. It wasn’t raining that hard and so I decided to leave the generator off-line until the next morning. The wind really howled until about three AM. The sky was constantly being lit up by the subtations near the canal as they flood and shorted out. The high tension transmission lines in the distance could also be seen lighting up the sky after one of the lines broke and shorted out. The only good news was that the rain never came as predicted. Things calmed down quite a bit by the next morning. When I went out to start the genset, I immediately noticed that there was some serious wind damage to the neighbors trees.
These pines had been planted twenty four years earlier when the house was built. The wind ripped one out of the ground, pushing it onto the others, which fell like dominos from the weight:
Next I went to check the road to see if it was passable. On the right side three big oak trees had been ripped out of the ground and were laying across the road:
Turn around to the left and several more large oak trees had fallen across the road. These trees had ripped all of the wires down for a span of three poles:
You can see the phone cable and the CATV hardline laying in the road. That hardline is the reason this web site went off line for so long. In the picture below, you can see that the power lines were also broken on both sides of the pole:
Remember those tennis ball sized objects that were pelting me in the dark the night before? Well it was pretty easy to figure out what they were the next morning:
Osage Orange fruits. The trees usually drop these after the leaves are gone in the fall. I was finding these 100 feet from the hedgerow after the storm.
I decided the left side was my best bet for a quick opening of the road. I got the chainsaw and the tractor. After about 20 minutes I had cleared a good path. Right after I finished pushing the limbs out of the road, I got off the tractor to pick up some small debris. When I got back on it, it wouldn’t start. Turns out the fuel solenoid picked a convenient time to give up. I ended up having to tow the tractor back up the hill into the driveway. I couldn’t completely clear the road because the phone lines were pretty badly stretched under the trees. I just cut a swath wide enough to drive through:
So now I have to get the tractor fixed, so I go to call the local John Deere dealer. No cell service. It looks like the local Sprint tower rook a hit as well. It’s only five miles away, I’ll just drive over. Yeah right. That five miles was littered with downed trees and power lines. These first pictures are about 3/4 of a mile down my road. Once again, the power lines had been pulled down for several pole spans:
The five miles to the JD dealer turned out to be closer to 15 with all of the obstacles and detours:
I also realized along the way just how lucky we were. A few poor souls ended up with trees on top of their houses:
And some more photos of just how badly damaged the power infrastructure was:
The end result of this was no power over a very large area for an extended period of time. All businesses were closed. No convenience stores, no banks and no gas stations. I had picked up a transfer tank fron Tractor Supply the day before the storm. This gave me 100 gallons of fuel for the generator. The genset has a six cylinder engine and consumes just over a gallon an hour. On day two I went out in search of fuel. There was none to be had anywhere (including the NJ Turnpike). On day three, a local Sunoco station opened. There were instantly lines that stretched for miles at the gasoline pumps. However, there were no lines at the diesel pumps. Since the stations were running on generator power, they would only accept cash. I managed to get 20 gallons. I did this for the next several days until finally the attendant warned me that the station was about to run out of fuel and wouldn’t be getting a delivery for several days.
Here’s a picture of the lines at a local Shell station. This line was almost two miles long and the station had no gas to sell:
We started cutting back on running the genarator to four hours in the morning and four hours in the evening. At my rate of consumption, the fuel would run out in three days. Over the next few days, I drove around the area looking for diesel. There was none to be found. I was just about to call it quits and move to another location for awhile when I happened to see a heating oil truck on the road. I called my fuel company and asked them to deliver 200 gallons. It was there the next day. This gave me enough of a buffer that I felt like we could hold out for a bit longer.
One week after the storm I saw PSE&G trucks on my road working on the power lines. When I came home later that evening, I noticed that most of my neighbors had power. When I got to my end of the road it was dark. I went out the next morning to see what had been done. To my dismay, the line had been capped about a mile from my house. They did this so they could bring a couple of very large subdivisions on line. It took another week for them to come back and get my power turned back on. In order to do this, they had to string new power lines for the last mile or so of the road. Once the power was restored I had to wait for Verizon and Comcast to come back and run new wires for their services. My internet access was finally restored last night.
In the end, we got by with minor damage to the house and barn. The genarator did well. It’s a pretty nice unit. It has a six cylinder Cummings diesel engine. It has a switching regulator and can put out single and three phase power. Here’s a few pictures:
I need to find an auto transfer switch and install a remote start/kill switch in the house. Another nice thing about this unit is that it’s not turbo charged. It spins at 1800 RPM and is relatively quiet. I might buy a 20′ sea container to house it in permanently.
Oh yeah.. Remember that fuel solenoid? After taking an hour to get to the dealership, I was surprised to find him open… But he didn’t have one in stock.
I ended up breaking the pin off the old solenoid and reinstalling it. The tractor runs fine, but you have to stall it to shut down. It’ll do until the new one arrives.
Anyway. Glad to have the lights restored and glad to be back on-line.
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