@@robertswaine6096 The smaller one has an automatic discount, so it is actually cheaper. You have to search the pictures (not the specs in print) to find the 2.5 safety factor claim for the smaller one.
I used lifting magnets a lot doing structural fabrication. Very useful for picking wide flange beams from beam stacks. As soon as the beam was high enough and clear of the flanges, always add cribbing then reset the lift using logger chains to move anything. Magnets can be unpredictable, always clean the bottom of the magnet with a brush to remove anything stuck on the magnetic surface, even a small amount of material can be enough to severely weaken the magnetic bond.
John and I worked at the same place in the 80’s. We used magnets a lot for plate steel but usually used scissor type beam clamps to pick up beams. We did a lot of structural work for the pipeline and John worked in the machine shop side of the shop. He looks the same now as he did back then.
@@asherdie Absolutely not. Fixed position magnets are reliable as the field never changes and a mechanical force is used to literally rip a component clear of the magnetic field. The magnets seen here are not fixed, as demonstrated by the video. The anticipated lifting force is clearly not within the expected capacity. This type of magnet in where the flux is interrupted by shifting the position of the field mechanically causes degradation of the strength of the field. This is typical of any natural magnet that can be switched on/off via positioning. Another very common illustration of the degradation is a magnetic base for an indicator, after so long and so many off/on cycles the magnetic field falls flat and the magnetic base is worthless. There are very limited safe applications where an item lifted with a magnet is considered "secure". Lift with a magnet, but move with rigging. Also, one last thing that is worth mentioning. Every magnet has a minimum cross sectional thickness that it's capacity is rated at. Further, that cross sectional capacity is rated with the homogeneous state of the material through which the cross section passes. Any variation in the cross section negatively affects strength, things like weldments, inclusions, part lines, etc all negatively affect capacity.
One thing that “ seemed “ to be was 500lbs on a thicker plate held better than 500 lbs of thinner plate. For example the magnets worked better on 1” vs 1/4” plate of the same weight. Flex in plates can cause the magnets to release.
I don't trust magnets for lifting But I saw a electromagnet on a crane pick up a iron block V8 engine by the rounded torque converter. their was a very small contact area for the magnet to hold on to yet it picked up the 600 lb. engine with no problem.
I looked after the testing & the steel type does play into the figure, I was using 4340, they claim this to be good for 90% of full spec on medium carbon alloy steel, which would make it look better, but still not 100% of expected. I have used the one a lot & also used other magnets years ago, while not meeting the full spec, I still think they are a good value, but I would keep the lower figures in mind when thinking of safety.
Did you try it on rounds? My casual experience is that rounds lift better than flats. I suspected that rounds fit the V surface better than non machined flats. My employer purchased only industrial brands and didn't substitute with knock offs. I have been retired long enough that I don't recall the brands that we used. Prior to the permanent magnet lifting devices we used battery operated devices. They performed well, but battery maintenance was required and their size limited use. The permanent magnet devices were a welcome addition. I was a maintenance technician, so I only had limited personal demand to use these devices compared to production staff. I don't have any magnetic lifters in my hobby shop. Your Vevor testimonial tempts me to look at this brand for a new shop toy.
I have used the old one on rounds. The instructions say to derate for round by 50%. I have seen them hold more than the 50%, I thi8nk this is because I am usually picking 4"-8" diameters, I think most people lifting 2" size would have low magnetic coupling.
@@HOWEES That is interesting. I never bothered to read a manual since my use mirrored proven routine operations production folk did every day. Much of maintenance hoisting was irregular shaped machine components they weren't suitable for a magnetic hoisting device. Our shop did a lot of rounds (lathe and cylindrical grinding). The magnetic devices were popular for handling raw material, saw operations, center/facing machine, lathes and cylindrical grinders. The ability to pick one roll blank or part without a strap attachment step was very handy. We used our devices on large diameter rounds as the weight demanded hoist assistance. Large flat plate material used the battery operated magnets. These units had a large footprint, but plates could be 5'x6', sometimes larger. I don't think we ever owned the permanent magnet sizes rated for those heavy plates. I know that never used a permanent magnet device for that heavy lifting purpose. Our plate material was delivered already Blanchard ground. We had good flat plate magnetic coupling. Round stock material varied in surface prep. Machine operators did use the permanent magnet devices for hoisting flats into the mills and for hoisting mill fixtures, but they were mostly employed on rounds. Our shop was exclusive production for our own products, no job shop work. We ran between 150k-200k part numbers each year approaching 1 piece flow, but operation processes were predictable and consistent. This helped us to refine processes and when proven didn't encourage much variability. Vevor is new to me. I have long steered away from less than the premium brands. We own a Vevor vacuum sealing machine, because we do so much home butchering and processing. I ran this unit several years before noticing that it was Vevor. The boys bought it, and I thought that it was a fully commercial model like our other processing machinery. It hugely outclasses any machine that I had previously operated. A typical family hog butchering is 13 hogs. This size of events (we do several hog and beef events annually) justifies equipment investment. Vevor seems to have their finger in every industry.
No supposed to, but I still think it will eventually. The lower lifting of my old one being less on the machined surface is probable due to surface damage to the lifter. It might have done better if I had used a stone on the face of the old magnet before testing.
Looks like a clone of your old one. Chinese seem incapable of designing anything themselves. Much of the junk they send reminds me of the term "cargo cult" engineering.
Larger PML600:
s.vevor.com/bfQoAo
Smaller PML600:
s.vevor.com/bfQkbx
@@robertswaine6096 The smaller one has an automatic discount, so it is actually cheaper. You have to search the pictures (not the specs in print) to find the 2.5 safety factor claim for the smaller one.
I used lifting magnets a lot doing structural fabrication. Very useful for picking wide flange beams from beam stacks. As soon as the beam was high enough and clear of the flanges, always add cribbing then reset the lift using logger chains to move anything. Magnets can be unpredictable, always clean the bottom of the magnet with a brush to remove anything stuck on the magnetic surface, even a small amount of material can be enough to severely weaken the magnetic bond.
John and I worked at the same place in the 80’s. We used magnets a lot for plate steel but usually used scissor type beam clamps to pick up beams. We did a lot of structural work for the pipeline and John worked in the machine shop side of the shop. He looks the same now as he did back then.
Magnets are very predictable, the use and application are not.
@@asherdie Absolutely not. Fixed position magnets are reliable as the field never changes and a mechanical force is used to literally rip a component clear of the magnetic field. The magnets seen here are not fixed, as demonstrated by the video. The anticipated lifting force is clearly not within the expected capacity. This type of magnet in where the flux is interrupted by shifting the position of the field mechanically causes degradation of the strength of the field. This is typical of any natural magnet that can be switched on/off via positioning. Another very common illustration of the degradation is a magnetic base for an indicator, after so long and so many off/on cycles the magnetic field falls flat and the magnetic base is worthless. There are very limited safe applications where an item lifted with a magnet is considered "secure". Lift with a magnet, but move with rigging.
Also, one last thing that is worth mentioning. Every magnet has a minimum cross sectional thickness that it's capacity is rated at. Further, that cross sectional capacity is rated with the homogeneous state of the material through which the cross section passes. Any variation in the cross section negatively affects strength, things like weldments, inclusions, part lines, etc all negatively affect capacity.
Good morning everyone
I'm a crane technician. I come across when doing inspections sometimes. Very interesting video 👍
One thing that “ seemed “ to be was 500lbs on a thicker plate held better than 500 lbs of thinner plate. For example the magnets worked better on 1” vs 1/4” plate of the same weight. Flex in plates can cause the magnets to release.
Hi John
Good video and good information. Thank you
I don't trust magnets for lifting But I saw a electromagnet on a crane pick up a iron block V8 engine by the rounded torque converter. their was a very small contact area for the magnet to hold on to yet it picked up the 600 lb. engine with no problem.
Is it just me or is the audio messed up around just past the middle of the video?
Could just be my app acting wierd.
It's the audio on Our part. I need to get Cameraman a better head phone set.
Now, I'm curious did you mention the kind of steel it is? Is it possible they measure those magnets on a closer to pure iron test plate?
I looked after the testing & the steel type does play into the figure, I was using 4340, they claim this to be good for 90% of full spec on medium carbon alloy steel, which would make it look better, but still not 100% of expected. I have used the one a lot & also used other magnets years ago, while not meeting the full spec, I still think they are a good value, but I would keep the lower figures in mind when thinking of safety.
Did you try it on rounds? My casual experience is that rounds lift better than flats. I suspected that rounds fit the V surface better than non machined flats.
My employer purchased only industrial brands and didn't substitute with knock offs. I have been retired long enough that I don't recall the brands that we used. Prior to the permanent magnet lifting devices we used battery operated devices. They performed well, but battery maintenance was required and their size limited use. The permanent magnet devices were a welcome addition.
I was a maintenance technician, so I only had limited personal demand to use these devices compared to production staff.
I don't have any magnetic lifters in my hobby shop. Your Vevor testimonial tempts me to look at this brand for a new shop toy.
I have used the old one on rounds. The instructions say to derate for round by 50%. I have seen them hold more than the 50%, I thi8nk this is because I am usually picking 4"-8" diameters, I think most people lifting 2" size would have low magnetic coupling.
@@HOWEES That is interesting. I never bothered to read a manual since my use mirrored proven routine operations production folk did every day.
Much of maintenance hoisting was irregular shaped machine components they weren't suitable for a magnetic hoisting device. Our shop did a lot of rounds (lathe and cylindrical grinding). The magnetic devices were popular for handling raw material, saw operations, center/facing machine, lathes and cylindrical grinders. The ability to pick one roll blank or part without a strap attachment step was very handy. We used our devices on large diameter rounds as the weight demanded hoist assistance. Large flat plate material used the battery operated magnets. These units had a large footprint, but plates could be 5'x6', sometimes larger. I don't think we ever owned the permanent magnet sizes rated for those heavy plates. I know that never used a permanent magnet device for that heavy lifting purpose. Our plate material was delivered already Blanchard ground. We had good flat plate magnetic coupling. Round stock material varied in surface prep.
Machine operators did use the permanent magnet devices for hoisting flats into the mills and for hoisting mill fixtures, but they were mostly employed on rounds.
Our shop was exclusive production for our own products, no job shop work. We ran between 150k-200k part numbers each year approaching 1 piece flow, but operation processes were predictable and consistent. This helped us to refine processes and when proven didn't encourage much variability.
Vevor is new to me. I have long steered away from less than the premium brands. We own a Vevor vacuum sealing machine, because we do so much home butchering and processing. I ran this unit several years before noticing that it was Vevor. The boys bought it, and I thought that it was a fully commercial model like our other processing machinery. It hugely outclasses any machine that I had previously operated. A typical family hog butchering is 13 hogs. This size of events (we do several hog and beef events annually) justifies equipment investment. Vevor seems to have their finger in every industry.
Do the magnets get weaker over time/with use?
No supposed to, but I still think it will eventually. The lower lifting of my old one being less on the machined surface is probable due to surface damage to the lifter. It might have done better if I had used a stone on the face of the old magnet before testing.
Is the bottom surface of your good ol one clean and flat?
It's scratched, and this may be the reason for the lower numbers on the nice surface, as it did better than one of the new ones on the rough side.
algorithm booster
5 syllables... ne o dy mi um
Yup. Niobium is a different element. Atomic number 41.
Looks like a clone of your old one. Chinese seem incapable of designing anything themselves. Much of the junk they send reminds me of the term "cargo cult" engineering.