Not much in this post, but its definitely worth mentioning if any readers care to make dollys for their machine tools.

A core tenet of the austinshop final plan is to have the surface grinder on wheels such that it can be wheeled outside to use, to protect the shop from being covered in grinding dust. To do this I need some way of wheeling it. And the surface grinder isn’t light, so it needs to be extremely strong.

I started with the door bits because they are nice, strong wood about the right size (read later post to see where those came from). I attached the casters with huge lag bolts, probably 3/8″ OD beeg boi bolts. Should be enough to keep the wheels from pulling out.

Using some amount of crowbar-ing, I lifted the surface grinder and supported it with some 2x4s while I removed the skids:

Then I lag bolted the dolly pieces on.

Success. It actually wheels really well on the epoxy floor. On asphalt though, different story.

Once the grinder exits the garage, it does get very difficult to roll, which is annoying. Luckily, I won’t be using this tool that often, so that is ok. When I roll it out of the garage, I make sure to roll it in the direction that it is less likely to tip over, because its pretty tippy on the garage ramp (lol).

I gave the grinder a brief run to see how it worked. I’d only really used a surface grinder once before, so it was kind of a cool experience. This one also has no autofeed, which is kind of a pain in the butt (or wrist actually). Definitely begging for some big brushless autofeed. Anyways, it was pretty cool to use this one though. The part I made actually turned out quite shiny, which was surprising- it had a high shinyness to effort ratio.

Definitely I should have used bigger casters for this, as I think these ones are only rated for 250lbs and this grinder is probably at least 500lbs. When going over rough ground the load basically is concentrated on a diagonal pair so I am definitely pushing the rated load for these 3″ casters. And it doesn’t even wheel that well over bumps- definitely wish the wheels were bigger. Also, the front and back pieces of dolly were flexing away from each other, giving the dolly a sagging look. I had to add a cross member to stop this. I definitely would recommend adding cross members to future dollies.

Also, I used my work’s mill to mill down the lathe drawer a bit. I then put Teflon tape on the bottom of the drawer. and WOW- what a difference the Teflon tape makes. The drawer slides like butter, even when FULL of carbide!

Anyways, another ramble! Time to write another….

A post which is kind of a cop-out because I wasn’t the one who put in the effort, but it’s worth mentioning.

The tarp mentioned in part 2 was not a permanent solution. A more permanent solution can be purchased with money: having some dudes come over and re-shingle the roof.

We got a few quotes and went with the best one. The dudes showed up right after a huge snow, so the first step was shoveling the garage. Then they got to work. It was pretty insane watching them go- these guys were roofing machines.

One kind of interesting effect was that when all the shingles on the garage were removed, the light shone through. It actually made the garage feel really nice, kinda makes me want some skylights. Whatever.

A few boards had rotted out, so we replaced them as the roofers went.

On the south side of the garage, there were some trees which had shaded the garage, and therefore an entire section needed to be replaced. Whatever. We got these trees removed, which was a bit sad cus they were kinda nice trees.

The only medium-big downer is that a lot of old shingle debris rained down between the cracks in the boards, which got all over the garage. I am still vacuuming this stuff up…

Anyways, now it doesn’t leak anymore. Yay!!

FINALLY- the big day. October 10th, 2020. The day where I increase the weight of my personal possessions by approximately 5000 lbs. Nothing like moving nearly 40 times your body mass.

Let’s back up one day though to the day before though, to October 9th, where I did some pre-move moving. I cleaned up a bit around the various tools, mostly around the Hardinge. The drawers on the Hardinge were the ‘summer set’ of drawers, as in, the wooden drawers had expanded and completely jammed about 6 inches open.

By aggressively rocking the drawers from side to side and up/down, I could get them to shift slightly in their slots. I spent about an hour wiggling all three drawers out, one millimeter at a time. How exhausting.

The other task was to reopen the door at the pack of the garage, which opened into a shed which I guess will serve as a sort of mudroom for the machine shop. Removing the plywood just required removing a few nails, and this old “Fro-joy” Ice Cream sign.

Additionally, in one of my previous trips to Home Depot, I acquired several lengths of 1″ PVC tube. Aaron and Al highly recommended the PVC tube Egyptian method as a way to move the machines. I was originally skeptical of this method, but it actually worked incredibly well.

Alright, time to get a good night’s sleep- because tomorrow is going to be a long day.

We met at Saugus at about 10am.. aaron refused to wake up any earlier (lol). I also stopped by home depot to get supplies, and met a 92 year old WW2 vet who apparently flew P-51s over Europe in WW2 when he was seventeen. WW2 vets are not very common these days- he said “Sadly I do not have too many old friends.” We talked for a bit, he was a cool guy.

The Linley was the first to get moved. I bought a bunch of 2x4s and 2x6s at Home Depot, and decided to use the 2x4s for this machine as I thought it was lighter. This turned out to be a mistake, definitely should have used 4x4s, but whatever. Turned out OK. We were lucky enough to have an electric gantry crane installed in the place, which was super useful.

The machine tool moving process was:

• Prepare 4×4 or 2×4 skids
• Used the crane to lift machine onto skids
• Lag bolt machine down to skids
• Prybar up the skids to put Egyptian tubes under skids
• Roll machine forward to lip of trailer
• Attach come-along to machine to pull it up trailer ramp
• Once machine is on trailer, either use come-along or pvc tubes to maneuver machine into final position in trailer.
• Ratchet strap machine down to trailer.

The Linley being lifted by the gantry crane:

The Linley and the surface grinder were the first to be moved. Here, nick poses for the camera.

The lift actually made things pretty easy, even with the mill which apparently weighs in at around 1200 lbs. It will definitely be a pain on the other end to do everything without the lift… next shop, gantry crane for sure.

Attaching the skids to the base of the mill was pretty challenging- the base of the mill is very thick so we had to find super long lag bolts. One thing I would do differently for next time is pre-cut all the skids the night before, making sure to bevel BOTH ends of the skids so the PVC rollers could easily slide under them.

The mill had ‘tight clearance’

And by tight clearance I mean zero clearance. We moved the trailer a bit until it fit.

Most of load 1!

Load 1 complete. I thought maybe we could get it all in one load, silly boi…

About a mile in, nick stomped on the brakes too hard and the Linley fell over. Luckily, it hit the back of the trailer, and therefore only fell about 45 degrees. We stood it back up and added more straps to tie it down.

The last time the garage floor is visible in its entirety.

Time to unload. Because we were stoopid, we had to do this in the dark, but it went pretty quick, only took an hour or two.

A good system we worked out was to use a 4×4 across the trailer which we effectively used as a capstan. With this, it was pretty easy to smoothly roll the mill down the trailer ramp. We did have to rotate the head to get it in the garage. NBD.

An exhausting day– time to do the whole thing again the next day.

Day 2, I kinda forgot to take pics. But, things went pretty well. The lathe was on a dolley so we kinda just rolled it over to the center of the garage where the gantry crane is, and then lifted it off the dolley. The dolley was small and bad, but we kept it anyways. I also got the shelving unit. The drawers on this guy are removable, so the process for moving it was to take all the stuff out of the drawers, then move it into the truck, then put all the stuff back in the drawers.

All loaded up. Nick got a set of shelves too!

Driving.

Arrival in arlington. Welp.. we got.. a loooot of stuff.

With the move done, it was time to relax over a beer with our many pounds of cast iron. Definitely the most interesting object we found in Saugus resurfaced in this move- any guesses?

Yep, thats right- a PULSEJET! We will fire it up some day at Aarons.

The garage was… FULL. Like 100%, FULL. Definitely many months of cleaning ahead!!!!

With all that moving done, it was time to breathe easy for a bit. But, still a lot of work ahead!!

Not too much of a post here, but worth noting. This post will not adequately convey the amount of effort put into the events covered, the ratio of effort to post length here is quite high.

So, the garage. When I moved in, I noticed that there was a broken rafter. Huh, interesting. We added a temporary stick brace.

Just out of curiosity, I decided to read up on rafter spacing building codes. It seems like most places have 12, 16, or 24″ rafter spacing, and mostly 2x6s because New England. I decided to measure the garage for kicks. The spacing was a little bigger than code:

Not 24 inches, nope.

Not 30, still nope.

Uhh, 36 inches? nope… wait what? Yep, bigger.

40? What?

NOPE- A whole 48 INCH SPACING. WHAT?? And to seal the deal the rafters were 2 BY 4S! Granted, the old style, actually 2″ x 4″ beams, but still. Everyone I told this to was incredibly surprised that the roof hadn’t caved in. Except that it had, or at least started to: one rafter was actually broken and most of the others were seriously sagging. So.. time to install some new rafters. I actually did some math out on this one, and found that the beams would hold the shingles plus one guy plus some snow with a safety factor of two, but that the slats would be pretty near breaking with a guy plus some snow. Kind of scary- its a miracle this place hasn’t caved in.

Anyways, what follows is some pics of what we did. The basic process was to cut the new 2×6 rafter to length, put it up there, jack it up so that it took the load (and un-sagged the saggy roof), and then install some plywood collar ties. This process was pretty time consuming, but did eventually work pretty well.

Above: jacking the rafters before adding the collar ties.

After a long time:

Yay! Now the roof is less likely to collapse… but it still leaks. Read on for more details.

How to vaguely guess the approximate ballpark size of moter required for your application. These are all ballpark numbers, but generally a good starting point for your average motor. Two important parameters: torque and speed.

Lets start with speed. This is the easy one:

• For small inrunners (4″ OD or less), max speed is somewhere around 12k-16k RPM. For Hobbyking inrunners it depends on the quality of construction. For some motors, the magnets will fly off the rotor at high speeds, so probably no not exceed 15k rpm. If the rotor has a carbon or kevlar overwrap (or is an IPM), you can push the upper limit here, but hysteresis losses and eddy current losses will start to become very large. If the motor has both low pole count and very, very fine laminations, you can really rip- apparently some people push 25-50k RPM.
• For big inrunners (8″ or more), max speed is probs 8k-10k RPM, but it depends a lot on how thin the laminations are, what the tooth shape is, etc. If you really want to know, test one til it ‘splodes. Apparently Tesla pushes their big inrunners pretty hard, up to 18k RPM. Again, these numbers can vary fairly wildly depending on a lot of factors: lamination thickness, mechanical integrity of rotor, etc.
• For small outrunners (melon size, 100mm or less), max speed is 8000 RPM. Experimentally Mason has verified that pushing an SK3 to 10k for extended periods of time will cause it to ‘splode.
• For big outrunners (6″ or more), 5k seems to be a good upper limit, as after this the eddy current and hysteresis losses become large.
• For linear motors or axial flux, it depends a lot. Axial flux motors come in all different shapes and sizes, but generally are not used at high speeds for whatever reason. Linear motors generally run out of track before they hit high speeds, so it is a non-issue.

Next up: Torque. This is a little harder, so we turn to mathematics. Basically, what is conserved across motors is magnetic shear stress produced in the airgap. Just multiply the surface area of the rotor by the radius and magnetic shear stress and you can get the torque.

T = S*A*R

where: T = shaft torque [N*m], S = magnetic shear stress [N/m^2], A = active airgap area, also equal to: (stator stack height) * (rotor rad) * 2 * PI [m^2], R = argap radius [m].

For linear motors, the equation is similar, just without the radius:

F = S*A

where: F = mover force [N], S = magnetic shear stress [N/m^2], A = active airgap area [m^2].

Rule of thumb values for what S is, depending upon the moter in question:

• For inrunners:
  • S = 25000 N/m^2 for air-cooled, continuous operation.
  • S = 45000 N/m^2 for peak torque of air cooled motor, as in 30 seconds at this torque smells like hot windings and after 1 min moter is on fire.
  • The MIT Cheetah robot which has specially designed inrunning motors rumored to go up to 190,000 N/m^2. However, this is obviously a pulse-torque application.
  • S varies wildly for water-cooled setups, depending on the thermal resistance to the water and the water flow rate. However, 40000 N/m^2 for continuous and possibly 60000 N/m^2 peak is probably a good place to start.
• For outrunners:
  • S = 11000 N/m^2 for continuous, air-cooled operation. Outrunners do not cool very well, and generally have significantly less copper than a comparably sized inrunner because there is just less stator area.
  • S = 36000 N/m^2 for peak operation (about 5 seconds).
  • Outrunners also vary significantly based on what they are mounted to and the stator stack height.
• For linear motors, use the same numbers as the inrunners. Linear motors are often water cooled and mounted to something big and heavy which can take the heat out very well, but often operate at low efficiency because of the end-effects. The inrunner numbers are a good place to start.

Happy motoring!! 🙂

Welcome back to the never-ending saga… here we go again.

With the epoxy disaster complete, the next thing on the extremely long list was to prep the machines in Saugus for moving. And by prep, I mean excavate.

Excavate? Yes, Excavate.

The machines were literally buried under about 6 feet of stuff, including hundreds of carburetors, at least 50 truck starter motors, at least 200lbs of NiMH and lead acid batteries, at least 20 small Briggs and Stratton small engines, super old welding gear, about six massive generators, and more heavy stuff. The two photos below were taken after about four hours of hardcode cleaning of me, Aaron, and Nick:

So, Aaron, Nick, and I went HARD. This was part of the deal- we got the machines for a pretty low price, but we owed a solid day of cleaning to excavate them. Anna also showed up to inspect the rubble!

After about six hours, the floor became visible.

I have to give Aaron a great deal of credit for exceptional junk sorting skills. I’ve never seen a man sort/plow through junk faster than him! Everyone was very impressed. One thing that the people wanted was for us to sort out the scrap metal separately from the trash, so that their friend could make a couple bucks on it. We probably sorted at least 1000 lbs of scrap metal. This is the pile about halfway through, it was at least 4′ tall by the time we were done. We also filled most of a 20 yard dumpster with actual trash.

One cool machine we uncovered was a Sebastian pedal powered lathe, which the owners had advised us might exist at the bottom of the pile. Definitely a pretty cool machine, probably dates to around 1900. Sadly, not much use to me because of the Hardinge, so I opted to leave it. However, this should definitely go to a good home.

This post definitely does not quite convey how much stuff/mass we moved, without even touching the machines yet-should have taken more photos! We must have moved at least 1000 lbs of stuff, more likely 2000 lbs. Thank you Aaron!

A good day. Read on for part 4: the great moving.