Measuring Destructive Testing Force with a 20 Ton Hydraulic Press

[@dav1dh0ff]

Ideally when calibrating the load cell, you would use a weight close to the max capacity of the load cell. If you calibrate at 5kg for a 2000kg load cell, any error in calibration will be multiplied by 2000/5=400 at full scale. If you were off by 0.1kg while calibrating, you could be off by 40kg at full scale. It likely doesn't matter a lot for your use case, but it is something to consider.

[@MAYERMAKES]

i did consider that, but the 5kg was the biggest reliable load i had on hand. idealy i would have put a weight in the 1t range on it.

[@MAYERMAKES]

If you are interested in the code in detail there is a bonus video on the Element14 community explaining it all!

[@AaronBStephens]

Great video. To take the project to the next level, you need to measure both displacement and force, which can be used to create a stress-strain plot, which allows for much more detailed analysis of material properties. The cheapest solution is a linear potentiometer, available in short ~ 1, 2, 4, 6" lengths. The better solution for not much more cost is to use a wire attached to a rotary encoder, so you end up with a wire linear potentiometer with a usable range of feet, but still accurate to 0.001".

[@MAYERMAKES]

Hmmmm

[@xXDeltaXxwhotookit]

Nice project Clem. Something you've probably noted from the HPC channel, load cells don't seem to like a build up of pressure followed by a rapid removal (when the thing you're crushing breaks)

[@MAYERMAKES]

Yes, this is Part of the reason I backedcup the pressurexslowly after resching 1t of pressure.

[@DustinWill]

Very nice vid. Love the modules method AND custom PCB equally!

[@MAYERMAKES]

thanks!

[@maicod]

Loved it Clem !

[@MAYERMAKES]

thanks!

[@maxbackflip2711]

Crazy how much pressure the resin withstood. I'm now curious how much it can take before it breaks.

[@MAYERMAKES]

part gemoetry plays abig role of course, will do some more testing and post to the project page on e14.

[@patstandley5373]

Hi Max!

[@lorandnagy3277]

Ideally, in a measuring system all of the load or force will be transmitted through the load cell. If the measured force is not fully applied through the load cell’s intended axial (typically perpendicular to the loading surface) direction, the measurement system won’t capture the correct reading -- in the long run might even damage the cell. Big thumbs up

[@MAYERMAKES]

yes, as you saw in the video the load cell is mounted directly between hydraulik jack and the DUT, some sheering due to the part geometry was unavoidable. so for more comprehensive tests i need to make ajig for a standardized specimen to keepo alignment consistent.

[@TheElectronicEngineer]

Can you test how much force it takes to brake a Hotdog, frozen at -20.

[@MAYERMAKES]

now there are two questons.....where do i get a hot dog and a freezer that gets that cold, btw I expect it to need very little force sub 100kg

[@ralphups7782]

Clem there is this KZbin channel, called Chernobyl family. and they have a Russian clone of a IBM xt, one of the original ROMs has lost legs due to rust but I think you could either build them a jig or a reader and flash it over on to a EPROM.? you and the team are the only super human geniuses how could do it with eyes shut.

[@MAYERMAKES]

thanks for pointing me there, I ll take a look at the channel. I think there are very knowladgeable people in their local communitiy who might be able to help much better than myself.

[@nevram0101]

How much is the loadcell you use and how to order?

[@MAYERMAKES]

You can get such loadcells across the net mostly at electronics/industrial suppliers like newark/farnell, I paid 60€ for mine at a lokal supplier.

[@davidpayne6709]

A DRO on a press - genius! A DRO on a press that also has serial output- more genius-er! Go 'science stuff'!

[@MAYERMAKES]

thanks, I hope you also noticed that its not just serial out , it could also directly type in a text doc on a pc. when adding an SD shield one could also log to a file directly on the device.

[@Workshopshed]

David, Mayer there are good examples of this using cheaper scales attached to an Arduino

[@AmRadPodcast]

What is a kg? 😁 Nice build!

[@MAYERMAKES]

cue the memes!

[@6935g]

Force is measured in N. kg is the dimension of mass.

[@MAYERMAKES]

I have explained your point in the video, and my reasoning for using kg instead of N for practical implementation.

[@magneticanimalism7419]

It should have a setting to test midichlorians 😁

[@MAYERMAKES]

little update : since I filmed the video I have learned that there is a successor library to u8glib named U8g2 that supports even more displays ! so you migth want to use the more modern one if you replicate this project.

[@asus3365]

Cool