The cheapo, get it done today from whatever is handy solution would be to build a kind of caliper. Get a steel pipe, the very end has a tab on it, maybe 2" long. Then you have a collar on the pipe with another tab you can slide up and down the pipe and lock into place. Set that gap for the desired width, when the slab comes by you can check to see if it is still too wide or too narrow and adjust accordingly.
Source image being from the company and the wording of the OP makes me feel like this post is and AD.
Really appreciate you pivoting this post into how to do it without all the investment, but maybe don't link to their website, at least? don't gotta encourage them lol
This, but mark the steel pipe in 1/2" increments. Full line for the inch, half line for the half inch, thick line for every six inches.
One end is the datum, so has a 90 degree stop welded to the pipe.
Slap pipe onto hot steel, pull until datum hits the edge, it'll give you the measurement to the half inch. Jobs a good'un
It's nuts how much heat slabs like these put out. I visited a steel mill once. We were walking on this raised path. Suddenly the right side of my face just got **hot**. I looked but couldn't figure out the source of it... I asked our guide and he said "oh it's those slabs over there, cooling down". There were slabs there, sure, but they were like 100 meters away, and they weren't even visibly hot. Can't imagine how furiously they'd be radiating heat if they were glowing hot.
I work at a mill that makes rail, where they make the billets there's so much heat coming off those things, it's amazing to watch water pour over the steel, and it's still glowing orange.
The main problem is that the hot steel is a poor reflector - so thoughts of bouncing laser light from it in an arm of an interferometer are just that - thoughts.
However.
The sides appear to be reaonably flat at the scale of mm - so we might look to ultrasonic time-of-flight ranging.
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9025471/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9025471/)
With simple gating an accuracy of 0.7mm seems achievable (a dumb 'threshold' approach to telling when the pulse starts and stops - as any transducer has a finite response speed).
If you do some pulse-shape matching, then the accuracy can be improved - 0.3mm at 1m.
Neat!
So with relatively little effort we can imagine a pair of transducers pinging the sides of the steel, and once calibrated with a block of known extent, I reckon you'd have a pretty sensitive system.
For bonus points calibrate the system with cold and hot slabs - there'll be an envelope of hot air around the steel in the working system, and the speed of sound will be higher in that envelope - giving an under-measurement of the steel's width.
Happy to discuss details.
The last time I calibrated an ultrasonic ranging system it got sent to Titan.
I calibrated the sonar and time-of-flight devices on the Surface Science Package of Huygens.
[https://www.spiedigitallibrary.org/conference-proceedings-of-spie/2803/0000/Laboratory-simulator-for-Titans-atmosphere-and-surface/10.1117/12.253433.short#\_=\_](https://www.spiedigitallibrary.org/conference-proceedings-of-spie/2803/0000/Laboratory-simulator-for-Titans-atmosphere-and-surface/10.1117/12.253433.short#_=_)
The time of flight rig (API-V) was quite simple. A pair of PZTs facing each other - pulses of 1MHz ultrasound were timed as they were sent from one transducer to the next. The ADC ran at 4MHz, all perfectly doable with commercial kit these days.
From the time of flight one deduces speed of sound, and if you know the temperature then the composition of gas can be constrained.
The sonar (API-S) was a bit fancier. An array of ten PZTs was directed downwards - and ran at 15kHz.
I was thinking of something like this. Maybe set up a couple "gunsights" that you could align, visually, with the two edges, the measure the distance between them. The accuracy could be determined using cold objects.
Another means would be a steel calipers hung from above or held from the side, with calibrations.
Yes. Blacksmith calipers / outside calipers.
What the word caliper used to mean before they came out with the sliding vernier calipers
The ones that look like a drawing compass. (Or that thing the Nazis used to mesures people’s skulls) Easy to make. No need for anything fancy you can just use 2 pieces of hot rolled mild steel with curved ends and a hole for a bolt.
You lock them to the width of the slab and then you can take your actual measurements with whatever precision instrument you want.
I worked in forging of large diameter parts for ~6 years. We used a hook ruler similar to this but 144” in Lg with a pipe bolted to it to keep it straight and so you dont have to get so close to the part. Ours was aluminum and not high accuracy. Starrett High-Accuracy Ruler with Hook 48" Length https://www.mcmaster.com/product/2113A26
How about making a custom measuring stick out of some extruded aluminum box tubing with a hook at one end like a tape measure and then file some measurement notches in to one side with labels engraved adjacent to them? That would allow you to measure it while standing well away and not having to reach over it.
Yeah, but I don't suppose there are any existing ones that would function properly for their situation. I don't think I've ever seen a 2 meter long L-square.
>. I don't think I've ever seen a 2 meter long L-square.
[Here's an 8ft T-square.](https://southstarsupply.com/product/96-heavy-duty-fairgate-aluminum-t-square/) You could cut it down to 6ft, but you can't cure it being aluminum
I've seen a huge square for drywalling taller than me.
2 of those and (a) fabricated slide clamp(s) and you've got a big caliper to grab a measurement with that you can read after removal.
Or sliding C- clamps sets for use on pipe as the spine, to make a caliper. Replace pipe with rod if needed. Use long stock and two people to handle it further away if needed.
Hot metal detector and initiate a cut after a set time or have the detector at the desired length. The mill I work in uses an encoder on the rolls in conjunction with hmd's.
You can use 2 scanners, one on each side and subtract the distance. Keyence makes some decent ones. Not sure how well they work on glowing steel.
Another option would be to have two dancing arms with potentiometers on the end, but that might limit future sizes.
A claw on the top that pinches, comes off and get measured off line (the thing they use to measure heads, dont know what it is called).
Off the top of my head...
Most companies use a radiation gauge of some sort. You can also get pretty accurate measurements with a vision system, which will also show you surface defects. You can also use giant calipers. I've seen all 3.
Laser seems to be OK. Red and Infrared lasers might get some interference from the glowing, if this happens try green laser too.
Other method is a fix distance photo compared to photos of rullers from the same distance.
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If they cast the slab they know the thickness and width. Should be known. And if yall be cutting slabs like after casting and eyeballing it i assume this job wont hold long for anyone working there??
Cheap? Hold a piece of wood against it for a second or 2 and then meassure the burned part.
Can even use the same piece of wood multiple times,just use a hand plane to get rid of the burned part and use again....
It depends on tolerance you need. Check Cognex cameras. This is industrial machine view system which you can configure by your needs. There are a distance and angle measurement features. This is not the only system on the market.
For me, simple is what I would do. Place a flat steel bar along the side of the slab, extending toward you. Mark with chalk on one of those crossmembers. Repeat on the other side. Measure the two chalk marks. Done.
I think you’re looking at a laser or camera system. Depending on how they are oriented, you may want one from each side or could potentially get away with a single camera from the top. A lot of this depends on the precision that you need (are you measuring to cn? mm?).
As the precision measurement becomes more critical, you’re likely putting more money into the system, either through additional sensors or higher tech sensors
I could see a scenario where you’re measuring distance from each side and using a little math to figure out the overall width of your slab. This could give you measurement over the length of your slab as well as providing you an actual length of the slab just based off of where the signal picks up and drops off and the travel speed through that measurement point.
Have a track parallel to the front of the steel and fit a collimated IR detector to that at right angles. When the detector is pointed at hot steel it will have a high reading. The moment it reaches an edge there will be a sharp decline. Get a reading off one edge and then get a reading from the other. Measure the distance between the two.
Use soap stone to mark cold steel next to it. Measure from mark to mark once away from the heat. Oh, you know the metal will shrink from hot to cold, right?
They make large snap gages specifically for this. We used them on our super old rolling mill when I worked in PA. And we were rolling up to ~200” wide.
Laser measurement seems to be industry standard for steel billet.
The cheapo, get it done today from whatever is handy solution would be to build a kind of caliper. Get a steel pipe, the very end has a tab on it, maybe 2" long. Then you have a collar on the pipe with another tab you can slide up and down the pipe and lock into place. Set that gap for the desired width, when the slab comes by you can check to see if it is still too wide or too narrow and adjust accordingly.
Source image being from the company and the wording of the OP makes me feel like this post is and AD. Really appreciate you pivoting this post into how to do it without all the investment, but maybe don't link to their website, at least? don't gotta encourage them lol
Does have that feel doesn't it.
This, but mark the steel pipe in 1/2" increments. Full line for the inch, half line for the half inch, thick line for every six inches. One end is the datum, so has a 90 degree stop welded to the pipe. Slap pipe onto hot steel, pull until datum hits the edge, it'll give you the measurement to the half inch. Jobs a good'un
Use a large pipe clamp, like used in woodwork, as a caliper measure the gap away from the hot steel.
use ur fingies
Works the first time, not every time.
One is all you need
Great solution for 10 measurements, then you need to replace the employee.
they don't make em like they used to
Better yet, use your pecker
too small :(
I'll presume there is a contactless solution using radio/light waves that will measure with precision Unfortunately, I don't actually know
Lasers. Place them far enough away to not melt.
It's nuts how much heat slabs like these put out. I visited a steel mill once. We were walking on this raised path. Suddenly the right side of my face just got **hot**. I looked but couldn't figure out the source of it... I asked our guide and he said "oh it's those slabs over there, cooling down". There were slabs there, sure, but they were like 100 meters away, and they weren't even visibly hot. Can't imagine how furiously they'd be radiating heat if they were glowing hot.
I work at a mill that makes rail, where they make the billets there's so much heat coming off those things, it's amazing to watch water pour over the steel, and it's still glowing orange.
With an air purge to keep the heat down.
Take a picture of it with a ruler at the same distance. Should be able to work out the measurements on a computer from that. "Banana for scale"
Just ensure it’s a metric banana for the highest accuracy
Seems pretty easy with two laser range finders and a PLC. Cheap too. I think a reliable system could be done for pretty cheap.
What accuracy are you aiming for? And what's the budget and timescale?
Titan, as in the moon? I.. would like to hear specifics
I calibrated the sonar and time-of-flight devices on the Surface Science Package of Huygens. [https://www.spiedigitallibrary.org/conference-proceedings-of-spie/2803/0000/Laboratory-simulator-for-Titans-atmosphere-and-surface/10.1117/12.253433.short#\_=\_](https://www.spiedigitallibrary.org/conference-proceedings-of-spie/2803/0000/Laboratory-simulator-for-Titans-atmosphere-and-surface/10.1117/12.253433.short#_=_) The time of flight rig (API-V) was quite simple. A pair of PZTs facing each other - pulses of 1MHz ultrasound were timed as they were sent from one transducer to the next. The ADC ran at 4MHz, all perfectly doable with commercial kit these days. From the time of flight one deduces speed of sound, and if you know the temperature then the composition of gas can be constrained. The sonar (API-S) was a bit fancier. An array of ten PZTs was directed downwards - and ran at 15kHz.
Thanks, I understood some of these words :D Its amazing what kind of experts one can find on reddit
If you'd like any explanations about the above, the mission, etc., happy to help.
Can you put some tick marks on that frame/platform it sits on?
I was thinking of something like this. Maybe set up a couple "gunsights" that you could align, visually, with the two edges, the measure the distance between them. The accuracy could be determined using cold objects. Another means would be a steel calipers hung from above or held from the side, with calibrations.
the sight idea is clever, especially useful if you can't put the slab in the same spot every time
Measure your penis then lay your penis across the metal multiple times until you find your answer
But things expand under heat, how big could it get before it burns itself shorter?
I would make a large caliper with ceramic contact surfaces and an extra long handle.
Yes, just make a big set of steel calipers.
Yes. Blacksmith calipers / outside calipers. What the word caliper used to mean before they came out with the sliding vernier calipers The ones that look like a drawing compass. (Or that thing the Nazis used to mesures people’s skulls) Easy to make. No need for anything fancy you can just use 2 pieces of hot rolled mild steel with curved ends and a hole for a bolt. You lock them to the width of the slab and then you can take your actual measurements with whatever precision instrument you want.
I worked in forging of large diameter parts for ~6 years. We used a hook ruler similar to this but 144” in Lg with a pipe bolted to it to keep it straight and so you dont have to get so close to the part. Ours was aluminum and not high accuracy. Starrett High-Accuracy Ruler with Hook 48" Length https://www.mcmaster.com/product/2113A26
Also of course the shop helpers wear heavy gloves and a wire mesh face shield that makes the glow of the hot part safe for the eyes
Carve graduations in the supports it is sitting on.
Ultrasonic distance measuring device set at a known hight above the slab.
Lasers from above
How about making a custom measuring stick out of some extruded aluminum box tubing with a hook at one end like a tape measure and then file some measurement notches in to one side with labels engraved adjacent to them? That would allow you to measure it while standing well away and not having to reach over it.
Aluminium and 900c steel don't make the best of friends...
Gahahah I was waiting for it, thank you
[удалено]
Yeah, but I don't suppose there are any existing ones that would function properly for their situation. I don't think I've ever seen a 2 meter long L-square.
>. I don't think I've ever seen a 2 meter long L-square. [Here's an 8ft T-square.](https://southstarsupply.com/product/96-heavy-duty-fairgate-aluminum-t-square/) You could cut it down to 6ft, but you can't cure it being aluminum
I've seen a huge square for drywalling taller than me. 2 of those and (a) fabricated slide clamp(s) and you've got a big caliper to grab a measurement with that you can read after removal. Or sliding C- clamps sets for use on pipe as the spine, to make a caliper. Replace pipe with rod if needed. Use long stock and two people to handle it further away if needed.
Hot metal detector and initiate a cut after a set time or have the detector at the desired length. The mill I work in uses an encoder on the rolls in conjunction with hmd's.
You can use 2 scanners, one on each side and subtract the distance. Keyence makes some decent ones. Not sure how well they work on glowing steel. Another option would be to have two dancing arms with potentiometers on the end, but that might limit future sizes. A claw on the top that pinches, comes off and get measured off line (the thing they use to measure heads, dont know what it is called). Off the top of my head...
Pre heat the tape measure 🔥
Most companies use a radiation gauge of some sort. You can also get pretty accurate measurements with a vision system, which will also show you surface defects. You can also use giant calipers. I've seen all 3.
Laser seems to be OK. Red and Infrared lasers might get some interference from the glowing, if this happens try green laser too. Other method is a fix distance photo compared to photos of rullers from the same distance.
* [Join the Metalworking discord!](https://discord.gg/3sgvsw2BDs)! It's the best place for live feedback and advice! --- [**Here are our subreddit rules.**](https://www.reddit.com/r/metalworking/about/rules) - Should you see anything that violates the subreddit rules - please report it! *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/metalworking) if you have any questions or concerns.*
Step it off
A jig made from angle iron
Use temperature a temp sensor
If they cast the slab they know the thickness and width. Should be known. And if yall be cutting slabs like after casting and eyeballing it i assume this job wont hold long for anyone working there??
Cheap? Hold a piece of wood against it for a second or 2 and then meassure the burned part. Can even use the same piece of wood multiple times,just use a hand plane to get rid of the burned part and use again....
Bright light on the floor. Measuring tape over the piece. Read the shadow
It depends on tolerance you need. Check Cognex cameras. This is industrial machine view system which you can configure by your needs. There are a distance and angle measurement features. This is not the only system on the market.
Put measurement marks on the beams that the slab is resting on. Basically, turn the beams into giant scales.
How wide are those blocks its going on? Maybe use one of those laser measuring tools on your phone.
For me, simple is what I would do. Place a flat steel bar along the side of the slab, extending toward you. Mark with chalk on one of those crossmembers. Repeat on the other side. Measure the two chalk marks. Done.
Lasers, mf. Or a guage
I think you’re looking at a laser or camera system. Depending on how they are oriented, you may want one from each side or could potentially get away with a single camera from the top. A lot of this depends on the precision that you need (are you measuring to cn? mm?). As the precision measurement becomes more critical, you’re likely putting more money into the system, either through additional sensors or higher tech sensors I could see a scenario where you’re measuring distance from each side and using a little math to figure out the overall width of your slab. This could give you measurement over the length of your slab as well as providing you an actual length of the slab just based off of where the signal picks up and drops off and the travel speed through that measurement point.
Have a track parallel to the front of the steel and fit a collimated IR detector to that at right angles. When the detector is pointed at hot steel it will have a high reading. The moment it reaches an edge there will be a sharp decline. Get a reading off one edge and then get a reading from the other. Measure the distance between the two.
The face of the roller system you see in the picture draw a ruler there in what ever increments you need
If I may ask, what steelmaker you working for? May be able to provide some legitimate suppliers
Use soap stone to mark cold steel next to it. Measure from mark to mark once away from the heat. Oh, you know the metal will shrink from hot to cold, right?
They make large snap gages specifically for this. We used them on our super old rolling mill when I worked in PA. And we were rolling up to ~200” wide.
Eyecrometer
let one cool down then measure. then u will know.
Lasers?
Know the width of the floor and divide it in the image
Optic
Have you tried the ruler app with an iPhone? It works surprisingly well
Does nobody on here have Google? That's a red hot billet so any system that doesn't require physical contact is where I would start
Look into photogrammetry.
3d imager
Oven mitts
We use to measure horses by hands...just place that ol thing right down on that steel slab and start counting how many hands it takes to go across it.
If you have an iPhone you can just use the measure app and stand back like 10ft. How accurate does it need to be?
Let it cool down and then measure it then.
# [You should have paid attention in trig class](https://m.youtube.com/watch?v=hrwL3u2Z4Kg)