Assessing Ryobi 40 Volt Batteries

July 31, 2022

I bought into the Ryobi 40 volt ecosystem with a lawn mower, leaf blower, weed wacker, and chain saw. I have a 6 AH and a 4 AH battery. While cutting and splitting wood this spring, it felt as if the batteries were really slowing down, but I could not come up with a good way to assess their capacity objectively.

I saw a YouTube video where they purchased a RYOBI RYi300BG 300-Watt Powered Inverter and then used that inverter to power fixed loads in order to evaluate the batteries. I bought the inverter and used a pedestal fan as a load, monitoring it with a power meter that I made a while back. This is what I discovered:

VoltageAmp HoursWatt HoursLoad (w)Estimated
HrsMinsSecsHoursPct of Rated HoursActual

It seems that both of my batteries are producing about 70% of their rated capacity. Unfortunately, I did not perform this measurement when I first purchased the batteries, so I cannot comment on how much they have degraded. I will try to repeat this measurement in about a year. Since the batteries come with a 3 year warranty, that should give me enough time to see if they need to be replaced under warranty.

The End of Civilization

July 24, 2022

What follows is a summary of information gleaned primarily from two books.

If one attempts to be as pessimistic as possible, one comes up with nuclear winter and climate change (CC) as the two primary candidates for The End Of Civilization (TEOC). I recently became aware of a third path to TEOC, demographic collapse (DC).

First, CC. While there are many CC deniers at the moment (and for the past decades), the book “The Physics of Climate Change” by Lawrence Krauss provides a detailed and sobering analysis of the physics of the situation. The bottom line is that, even if we were to stop introducing greenhouse gasses into the atmosphere tomorrow, CC is here to say, for centuries if not millennia. We do need to take action against CC now, but the truth is that nothing that we will do will affect us for a very long time; and this makes the argument for immediate action lack any immediate reward.

There are some technologies that could cool the earth fairly rapidly (the dispersal of aerosols in the upper atmosphere), but they have both technical and political problems. Technically, the proposed aerosols use sulfur compounds which will further acidify the ocean once they fall out of the atmosphere. Politically, while ending CC will be good for people on average, it is unlikely that universal approval will occur, likely delaying any technical solution.

The more sobering problem appears to have no technical solution. In the book “The End of the World is Just the Beginning”, Peter Zeihan outlines the forces that have brought us to a DC.

I was unaware that DC was even a “thing” until I read this book. I applauded the Chinese when they adopted the One Child policy, decades ago, because I saw over population as burdening the planet’s resources to the point where we were doomed. It turns out that the actions that China took, with the best of intentions, will destroy them fairly quickly. Best intentions, etc…

Five hundred years ago, most people lived on the country side, with some in cities. Birth rates were high partly to offset mortality, but also to provide labor for agriculture. Advances in medicine increased life span, increasing the population and reducing the perceived need to create more babies. The advent of cheap energy reduced the need for agricultural labor, pushing people out of the country and into the cities. And people around the world, envying the First World’s standard of living, attempted to emulate it by “modernizing” with industrialization and urbanization. Each society did this at different times and at different paces. And once in the cities, people tended to have fewer babies, because of increased life span and reduced need for manual labor. You can add contraception and women’s rights into this, which further reduced birth rates.

Once birth rates slow down below the replacement rate, it is hard to recover, because there are so few young people to create families, and because the social forces that reduced the birth rate remain in effect.

For most of history, there were more babies than children, more children than teenagers, more teenagers than adults, and more adults than old folks. This provided a near-ideal number of people at each stage of life, with few old people to be supported by a large number of younger people. Urbanization and the sudden reduction in birth rates has turned this around. There are much fewer young people than older people now. This can be seen to some extent with the Baby Boomers, who are about to need financial and physical care from a work force that is much smaller than they are. But this pattern is about to occur world-wide, and it is inexorable: you cannot create 20 year olds to fill the gap without waiting 20 years. There is no fix.

I suppose one way to deal with this would be to select and kill older people, in order to shape the demographic graph back towards an ideal. While this may well be a good theoretical solution, it seems unlikely to be chosen.

The combination of CC and DC will likely destroy civilization in the next 100 years, but it will not be an easy death. Agricultural patterns will shift with CC, and political unrest and mass migration will result, destabilizing many governments. With not enough workers, products will not be manufactured, and markets will collapse as purchasing power declines. And with a global economy, that destabilization will trigger problems and unrest in all of the world. Countries which are somewhat immune (and that might include the US) will become the target of envy and mass migration. It will not be a pretty picture.

I recommend that you read both books and see whether you remain optimistic for the world past about 2050.

Why You Should Avoid Expedia

July 4, 2022

Expedia has screwed us over twice, so we are done with them.

The first time, I was trying to book a flight from Burlington, VT to Raleigh, NC. Expedia showed a price of $243 per passenger, until I tried to book the flight: then it became $387 per passenger. I switched over to the Jet Blue site, and was able to complete the purchase for $243 per passenger.

The second time, my girlfriend booked a rental car from LA to Washington state for 3 weeks for about $3K. They immediately took $1,386 out of our account, on May 12th. But when she arrived to pick up the car on July 4th, Expedia explained that because we were using a debit card, they could not rent the car to her. The account was good enough to take $1,386 of our money for seven weeks, but not good enough to complete the sale. They then refunded $230 out of the $1,386, explaining that someone else had to refund the balance; so, they will have our money for a while longer.

It is [perhaps] reasonable that a debit card cannot be used to rent a car, but if this is the case, it needs to be stated up front. What Expedia did was robbery. How much money has Expedia appropriated in this manner, from dozens or hundreds of people, across the country, for months? They need to be held accountable.

When USPS Screws Up, It REALLY Screws Up!

June 23, 2022

On June 9th, 2022, I mailed a package from Fairfax, VT, to Dennis Port, MA. It went out for delivery in Dennis Port on June 13th, but was refused for some reason. On its way back to me, it went to Boston, MA; Nashua, NH; Burlington, VT; Nashua, NH; Shrewsbury, MA; Providence, RI; Wareham, MA; Dennis Port, MA; and Atlanta, GA. The USPS asserts “Your package … is on track to be delivered to its final destination.” What a ridiculous statement.

USPS Tracking®

Tracking Number: 9500115787812160496590

Your package is moving within the USPS network and is on track to be delivered to its final destination. It is currently in transit to the next facility.


In Transit to Next Facility

June 21, 2022


Delivery Instructions

June 21, 2022
In Transit to Next Facility
Your package is moving within the USPS network and is on track to be delivered to its final destination. It is currently in transit to the next facility.

June 19, 2022, 11:50 pm
Arrived at USPS Regional Facility

June 18, 2022, 10:22 am
Departed USPS Facility

June 18, 2022, 7:24 am
Arrived at USPS Facility

June 18, 2022, 6:00 am
Departed USPS Facility
WAREHAM, MA 02571 

June 17, 2022, 7:56 pm
Arrived at USPS Facility
WAREHAM, MA 02571 

June 17, 2022, 6:54 pm
Departed USPS Regional Facility

June 17, 2022, 6:11 am
Arrived at USPS Regional Facility

June 17, 2022, 5:19 am
Departed USPS Regional Facility

June 17, 2022, 4:51 am
Arrived at USPS Regional Facility

June 17, 2022, 3:39 am
Departed USPS Regional Facility

June 16, 2022, 10:48 pm
Arrived at USPS Regional Facility

June 16, 2022, 4:48 am
Departed USPS Regional Facility

June 16, 2022, 1:36 am
Arrived at USPS Regional Facility

June 15, 2022, 11:42 pm
In Transit to Next Facility

June 15, 2022, 10:11 pm
Departed USPS Regional Facility

June 15, 2022, 12:43 am
Arrived at USPS Regional Facility

June 14, 2022, 11:44 pm
Departed USPS Regional Facility

June 14, 2022, 10:31 pm
Arrived at USPS Regional Destination Facility

June 14, 2022, 3:49 pm
Return to Sender Processed

June 14, 2022, 8:05 am

June 13, 2022, 7:43 am
Out for Delivery

June 13, 2022, 7:32 am
Arrived at Post Office

June 13, 2022, 6:11 am
Departed USPS Facility
WAREHAM, MA 02571 

June 13, 2022, 4:03 am
Arrived at USPS Facility
WAREHAM, MA 02571 

June 13, 2022, 3:08 am
Departed USPS Regional Facility

June 12, 2022, 4:52 pm
Arrived at USPS Regional Facility

June 10, 2022, 12:57 pm
Arrived at USPS Regional Facility

June 9, 2022, 4:47 pm
Departed Post Office
FAIRFAX, VT 05454 

June 9, 2022, 10:48 am
USPS in possession of item
FAIRFAX, VT 05454 

Why You Cannot Trust FedEx Tracking

April 21, 2022

We’ve all had moments when tracking (for FedEx, UPS, USPS, etc) seemed off, but it usually resolves itself in a few hours. This situation is different.

I ordered a UPS from NewEgg through one of their selling partners. At 11:05 AM on 18 April 2022 I received email notification that the UPS had been delivered. The FedEx tracking looked like this:

At 3:53 AM on 19 April 2022 I received notification from NewEgg that my Return Request had been submitted. This was news to me, since I had not submitted a Return Request. I had not even seen the package yet (I had been too ill to walk down to the mail box)!

One minute later, I received the following message from the NewEgg seller: “Because the package was damaged in transit and was sent back by the courier company, I will refund you now, sorry”

The package never arrived here. In fact it was returned to the sender. But the FedEx tracking information shows, in excruciating detail, how the package was “delivered” to me “here”.

You might think that this is just an amusing example of bureaucratic incompetence, or of computer error, but it is more than that. If the seller wanted to, they could have insisted that the package had been delivered (even though it had not), using the erroneous FedEx tracking data as “evidence”. And then I would have been unable to reclaim my refund. There is no way to “prove” that a package was not delivered when the FedEx tracking information is a lie.

The fact that FedEx tracking is so flawed should be a serious concern to anyone who is purchasing products on-line. By which I mean, of course, everyone.

Dust Shoe for Shapeoko 3 XXL for Deep Cuts

January 16, 2022

I purchased a Shapeoko 3 XXL CNC machine a few years ago. I’ve not used it much, but it has worked as advertised most of the time. I purchased it to make parts with fairly deep cuts (2.5”-3”) and the dust shoe/boot provided, while superb for shallow cuts, was useless for deeper ones. I tried using a shop vac with a 2” hose, but they are not designed to run for 24 hours, and I felt that I needed a larger hose (more flow at a lower pressure) so I bought a dust collection system with a 4” hose.

I designed and 3D printed a series of shoes out of NinjaFlex Cheetah (a kind of TPU), essentially a larger version of the Shapeoko shoe. That worked, but because the boot was attached to the spindle, as the cuts became deeper towards the end of the job, the shoe could end up pressing against the top of the work piece if I was not careful.

I did some research, and there appear to be 3 kinds of dust shoes:

1) ones that attach to the spindle, and thus go up and down as the spindle is moved during the job; the Shapeoko came with a great shoe of this type, but only for small (1”) depths of cut, and only for 2” vacuum hoses;

2) those that attach to the gantry, and remain at a fixed height over the work piece during the job; and

3) those that float over the work piece. The floating shoes seem to be the best, but they have a potential fatal flaw: if the work piece has sudden drops (walls), then the shoe can get stuck because it cannot get over that wall. You can learn more about floating dust shoes here:

Most of the commercially available dust shoes either are limited to 2” hoses or are attached to the spindle. It seemed that if I wanted a 4” dust shoe that attached to the gantry, I needed to design and build one myself.

Here is a picture of all of the parts. I printed the parts in distinct colors so that it would be easier to understand the structure of the design. If all of the parts were black, it would look better, but it might be more difficult to understand.

The lower left green part is the bottom plate, with a hole for the brushes; the lower right green part is the top plate, with a clearance hole for the spindle, a friction fit hole for the 4” vacuum hose, and 10 recesses for magnets to connect to the sides; the two red parts are the side supports, with a T to connect to the CNC and magnet recesses to connect to the top plate; the blue box is the wall that separates the top and bottom plates; the black tube supports the 4” vacuum hose and is attached to the top plate; the comb-like black part is the brushes, prior to gluing into a circle; and the black part on top of the green parts is the part that attaches to (sits on) the gantry.

Here is the part that attaches to the gantry. It has slots in the back to slide over the gantry plate, and T slots in the front to accept the side pieces.

Here are the sides. They attach to the gantry via the T slots. There is a hole which can be tapped to 1/4-20 for a thumb screw to tighten the sides to the gantry, along with a small counter bore for a pressure pad. There also are recesses to allow magnets to be glued in place.

Here is the vacuum support. It is glued into the top plate to help support the vacuum hose.

Here is the wall piece. It is glued between the top plate and bottom plate. In the end, I used double sided tape to avoid the mess of super glue (that worked for a while and then separated).

Here is the top plate. The large hole is for the vacuum support cylinder and the small hole is a clearance hole for the spindle. The 10 magnets attach to the undersides of the two side pieces.

Here is the bottom plate. The four key holes align with tabs on the brushes:

Here are the brushes. They are printed flat in TPU and then glued into a cylinder. The fingers on each end provide a large surface area for gluing.

I considered super glue to fasten the plates to the walls, but ended up trying double sided tape. In use, the vacuum should pull the plates towards each other, strengthening that bond. That worked fine until I left the assembly hanging for a few days, and the bottom plate fell off.

Most of the prints were made with Prusament PETG; the walls were made with Prusament PLA (for no good reason, other than the color); the brushes were printed in Cheetah TPU.

None of the parts printed correctly the first time; the design required a lot of tweaking. All of the parts can be printed on a Prusa MK3S, although some of the larger parts just barely fit. In fact, you have to turn off the skirt in order to get the walls to print. The table shows the weights and print times for each part.

PartWeight (g)Print Time
Double Strut11411:42
Top Plate976:35
Base Plate1087:00
Vacuum Support272:47


The Double Strut (black) fits over the gantry back plate and has two T slots in the front. Each Side (red) slides down into the T slots. The Top Plate (green) has the Vacuum Support (black) glued in place and then the Top Plate is glued to the Walls and the Walls are glued to the Base Plate. The Brushes can be inserted or removed as needed. The main assembly snaps into place onto the bottom of the Sides using 5 strong magnet pairs on each Side. The spindle slips through a clearance hole in the Top plate and can poke out the bottom of the Base Plate. The main assembly can be removed for bit changes. The 4” vacuum hose is a friction fit into the Vacuum Support.

Well. How did it turn out? There were some surprises.

1) The Double Strut extends laterally past the edge of the gantry, so the CNC was unable to home in the X direction. After shutting the CNC off after it made loud grinding noises, I had to add a steel slug on the right side (with double sided tape), after which the CNC could home successfully, but I lost perhaps an inch of travel on the right side.

2) The above meant that the Bit Setter was no longer in the right place: I moved it.

3) The brushes were a total failure. I had to put the box all the way down on the bed to get it under the bit, popping the brushes inside the box. I retrieved the brushes and put them in place, but once the vacuum was turned on, the brushes vanished inside the main chamber again. I did the rest of my testing without the brushes. It went OK; I have no idea whether the brushes would have helped or not. Maybe the bottom plate also needs to be attached with magnets.

4) When the spindle descended fully (2.5”), the bottom edge of the plate on which the spindle is mounted (not the gantry palate itself) hit the back of the big box, pushing the back of the box down a bit. The magnets were strong enough that the box never detached: it just tilted and waited for the spindle to go up again. Unsettling, but not harmful. A minor tweak (a mm or two) on the main box dimensions should take care of that.

5) The next one is not a surprise, but you really cannot see what is going on with the cutters. You have to be patient and optimistic.

I’m glad that I made the shoe, but I’m not sure how much I will use it. I ordered a V7 shoe from PwnCNC: we will see how that works out.

Deep Do Do

January 9, 2022

When one makes a simple statement, it is often like “I believe in the Covid vaccine”. When one is challenged, and feels that one must defend their position, the statement changes to “I do believe in the Covid vaccine”. The “do” is used for emphasis, to make it clear that you mean what you say, despite opposition.

Recently, it seems that the “do”s are no longer optional. Everyone (reporters, interviewers, interviewees, etc) includes their “do” automatically. Even when unchallenged, the “do” is unfurled. Taking preventive action? Pretending to be really certain about a simple statement?

This appears to be yet another grammatical tic (like the “is is”, the “is was”, and the refusal to say “an”: see my other rants). Simply saying that you believe in the vaccine is deemed inadequate.

I don’t suppose that this is damaging, other than if you start out with emphasis, what is left for you to do if you really want to emphasize something? You’ve shot your wad before seeing the whites of their eyes. It is a bit like the up-talkers (who are now omnipresent), where every phrase ends with a rise in tone. This used to be reserved for questions; now every sentence seems to be filled with question after question, all of them rhetorical statements.

I now know what it feels like to be old. The language which I spent so many years attempting to master is melting and transforming in ways that I fine offensive.

OK. So. If this is my worst problem, life is good. Or perhaps life is is good. Or perhaps I do believe that life is is good?

Ignorance in the Face of Education

October 20, 2021

While listening to “Best of WWDTM October 2021” [WWDTM = Wait, Wait, Don’t Tell Me], I was treated this stunning display of ignorance. The interview was with Dr Ellen Stofan, former Director, Smithsonian Air & Space Museum.

WWDTM: Did Jeff Bezos and his crew actually go to space?

Stofan: Yes, they did. By any definition they made it above what’s called the Karman Line so they were actually in space.

WWDTM: The Karman line?

Stofan: Yes. There’s a famous mathematician called Theodore Von Karman and he was the one that calculated where it was where you would be officially beyond the earth’s gravity, that’s where you go weightless in space.

WWDTM: They were in the shallow end of space?

Weightless does not magically occur at or beyond a specific altitude. One can be temporarily weightless even near the ground if one simply falls off of a cliff. NASA makes people weightless for short period of times by diving a plane at just the right velocity.

Weightless occurs when one is able to fall without encountering something to stop one. Being in orbit (at any altitude) is essentially falling just fast enough to stay in orbit, so one is weightless. But these elementary facts of Physics seemed to be beyond Dr Stofan, who was raised by a NASA rocket engineer [], and who has spent more than 25 years in space-related organizations []

In fact, the Karman line is an altitude of 100 km, above which the atmosphere is too thin to support aeronautical flight. An aircraft at this altitude would have to travel faster than orbital velocity to obtain enough lift to support itself. []

From Karman’s autobiography, “Where space begins… can actually be determined by the speed of the space vehicle and its altitude above the Earth. Consider, for instance, the record flight of Captain Iven Carl Kincheloe Jr. in an X-2 rocket plane. Kincheloe flew 2000 miles per hour (3,200 km/h) at 126,000 feet (38,500 m), or 24 miles up. At this altitude and speed, aerodynamic lift still carries 98 percent of the weight of the plane, and only two percent is carried by inertia, or Kepler Force, as space scientists call it. But at 300,000 feet (91,440 m) or 57 miles up, this relationship is reversed because there is no longer any air to contribute lift: only inertia prevails. This is certainly a physical boundary, where aerodynamics stops and astronautics begins, and so I thought why should it not also be a jurisdictional boundary? Haley has kindly called it the Kármán Jurisdictional Line. Below this line, space belongs to each country. Above this level there would be free space.” []

I guess that no one associated with the WWDTM show had enough education to question an expert like Stofan, so they not only broadcast her blooper, but re-broadcast it as “Best of”. Quite an indictment of the education of all of these people

Oh no! Another Release of the PowerBelt3D Zero printer! Look out KickStarters!

July 15, 2021

I have spent well over $1,000 trying to get my PowerBelt3D Zero printer working. When the original belt was too wrinkly, I purchased a stainless steel belt. When that proved to be too easy to crease, I purchased a spring steel belt. When that failed, I ordered a replacement belt for the Creality CR-30 printer. When the original PVC rollers bent too easily, I replaced them with stainless steel pipe, designing and printing the hubs/couplers myself. I designed a variety of minor improvements, but the bottom line is that the printer still does not work. At this point, the extruder is not working reliably. Adam, the creator of the printer, has not been helpful.

When I received the kit, I reported that the power switch assembly was faulty, and that the power supply was faulty. Of course, the belt was also inadequate, and the rollers warped.

At that time Adam said on his web site “We’re on a mission to empower people with technology. We can’t do that without standing by our products.” and “If anything arrives non-functional, or breaks within 90 days of receiving your products, we will replace those components free of charge.” Adam did not live up to his promises. Even after I offered to pay for replacement parts, Adam ignored my request. He has replaced none of the components, let alone free of charge. It is interesting that the quoted phrases are not visible on his web site any longer. I guess he realized that he is unable to stand by his products.

So, I was astonished to receive an email that said “For a little while now, I’ve known that the Zero isn’t the best 3D printer to build the future with. That’s why for the past couple month’s I’ve been building and testing a brand new conveyor belt 3D printer. It’s designed to have a larger build volume and smaller footprint on your desk – and takes advantage of everything I’ve learned from the Zero since 2018.” It appears that Adam is about to launch a KickStarter campaign.

I urge anyone who is considering purchasing one of his printers to think really hard before purchasing one. I asked on his private FaceBook group whether anyone was successfully using their printer. One person said “I think they are parts machines”, by which I think he means that you buy a bunch of parts, but it never works as a printer. Another said “I had really good prints going (see previous posts) been [but?] have since been getting consistent jamming. Haven’t touched it since” That same person also said “What do I need to do to get my hotend to print consistantly. I get lots of clicking and clogging during prints. I know it has to do with the heat break and heatcreep. Is there another hotend that isn’t hacked that I can throw on this thing?” Since the group is private, there is no way for you, the potential purchaser, to see what you are getting into ahead of the purchase.

I offered to Beta test Adam’s new design. If he sends me a printer, and if it works well, I will report about that honestly. But I will also report honestly if the new printer does not work well.

This has been a huge waste of my time, effort, and money.

How To Convert A Chipmunk Into A Toad (Hint: You Will Need A Cat)

July 11, 2021

When the weather gets warmer, our cats start going outside, and hunting is instinctive and spontaneous for them. Sometimes we are able to rescue the victims, but not always. Some get eaten, while some wander off to die of their injuries. Not pleasant, but natural.

We knew that something had died because of the smell, and eventually located the chipmunk corpse behind a paddle board. It was pretty far gone, with maggots emerging from the body. And right next to it was a fairly large toad, just waiting to munch on each maggot as it came out.

In a strange way, the cat’s killing of the chipmunk allowed both the flies to lay their eggs, and the toad to eat the maggots. The maggots converted the chipmunk body into bite-sized pieces that suited the toad perfectly.

Not quite sorcery, but a bit of biological magic, even if the death of the chipmunk is sad to me. I wonder why the death of the maggots is not so sad to me.