You bet, a guard would be great...
...until the corner of the workpiece hangs on the guard in the middle of the cut. Then you have to turn the power off with your toe. Clearly, safety should be the first consideration in the shop.
Ever seen a mill with a guard? For that matter, how about a lathe with a guard near the tool and material?
The technique above looks OK to me. Note the 3/4" MDF pusher board. No hands on the cut off side. Finger tips only. And most likely an escape route... a fast way to get out of the whole kit 'n kaboodle if things go f**led up.
I have been in many Euro shops. Safety is good. And machinery with the CE marking can be trusted to supply excellent guarding and redundant electrical circuitry relevant to safety. Some differences exist... here, for example, we ALWAYS are obliged to wear safety glasses, in Europe, only when you REALLY need them.
Machines are run differently in the United States. The old saying is "Crank it up until the machine stalls, then back the feed off 5%", or, "run it like you stole it".
I only need one hand to order six beers...but it's not pretty!
...until the corner of the workpiece hangs on the guard in the middle of the cut. Then you have to turn the power off with your toe. Clearly, safety should be the first consideration in the shop.
Ever seen a mill with a guard? For that matter, how about a lathe with a guard near the tool and material?
The technique above looks OK to me. Note the 3/4" MDF pusher board. No hands on the cut off side. Finger tips only. And most likely an escape route... a fast way to get out of the whole kit 'n kaboodle if things go f**led up.
I have been in many Euro shops. Safety is good. And machinery with the CE marking can be trusted to supply excellent guarding and redundant electrical circuitry relevant to safety. Some differences exist... here, for example, we ALWAYS are obliged to wear safety glasses, in Europe, only when you REALLY need them.
Machines are run differently in the United States. The old saying is "Crank it up until the machine stalls, then back the feed off 5%", or, "run it like you stole it".
I only need one hand to order six beers...but it's not pretty!
chipco3434 said:
Ohh, so only fingetips are gonna get chopped off, now thats reassuring 😉
If I had seen an apprentice do something like that, I would most likely have had a few words with him. I again dont know about the rest of the world, but here we do not accpt such risks being taken. Hence we have VERY few injuries here.
According to the european regulations, the emergency stop must be within reach of a different bodypart than the hands...for instance the forehead if on a drill press, or the knee if on a saw.
In europe you also have to have a guard on a lathe now...I retrofitted a lathe with a guard as late as last week to make it legal. You hardly see any manual milling machines in europe anymore, so i guess thats why little attention have been paid to make them safer, but for a CNC milling machine, you cant en´ven get near the rotating mill....the entire machine is screened off.
Magura🙂
I felt pretty comfortable doing those crosscuts (in a pic). However, when cutting on the width, I didn't put my hand on the piece, but used a wooden block to press it against the table. I used another block to hold the piece against the fence and I was feeding material by pushing a longer piece of wood with my stomach😉
The good thing about whole setup is that the power on the saw is not that big, and when something is not right, the blade rather stops, instead of throwing things at me. Over the years I cut myself badly only once, while cutting thin sheetmetal on radial saw.
I used the setup below initially for any metal cuts. The material was firmly clamped to the table and I could slide the circular saw over it. It was very save, but not convenien, required too much time to setup and accuracy wasn't what I needed. Later, I tried using a table saw, and results are very good.
Safety glasses are mandatory and I'd rather recommend proper judgement than blindly following safety rules. Sometimes the rules act against your personal safety and only you can decide what's you comfort zone is.
The good thing about whole setup is that the power on the saw is not that big, and when something is not right, the blade rather stops, instead of throwing things at me. Over the years I cut myself badly only once, while cutting thin sheetmetal on radial saw.
I used the setup below initially for any metal cuts. The material was firmly clamped to the table and I could slide the circular saw over it. It was very save, but not convenien, required too much time to setup and accuracy wasn't what I needed. Later, I tried using a table saw, and results are very good.
Safety glasses are mandatory and I'd rather recommend proper judgement than blindly following safety rules. Sometimes the rules act against your personal safety and only you can decide what's you comfort zone is.
Attachments
What Peter shown here seem very safe compare to my first usage of a mitre saw for diy audio. It came with a standard 10inch ripping blade and I used it to cut a roughly 4 inches by 3 inches PCB, trying to trim an inch off. Used just my left hand to hold the PCB and my right hand pull down the saw and POW I could not see the PCB anywhere except just some red pieces everywhere. No, not my blood, the red bits were the red platic blade guard at the base of mitre saw where the blade goes thru. The blade flexed/wobbled so much and yet I was lucky my left hand did not moved or jogg with reflex action otherwise ...no there is not enough do and don't do regarding partical usage of power tools...
Regards,
Chris
Regards,
Chris
Fingertips are very necessary. Otherwise nose picking is difficult. As for apprentices, I concur. Clearly this usage of a table saw is NOT a lesson for novices. Period.
Personally, I'm not a woodworking guy. Table saws can be tricky devils and I still have a mark on my stomach to remind me.
There aren't many fun AND SAFE hobbies.
Personally, I'm not a woodworking guy. Table saws can be tricky devils and I still have a mark on my stomach to remind me.
There aren't many fun AND SAFE hobbies.
According to the local emergency ward stats, DIY is the most dangerous thing you can possibly do, its worse by a magnitude than for instance motocross and car racing....
With that in mind, I believe that unsafe practice is not to be spread by this forum.
Id personally rather that people go and have a block og metal cut by somebody who's got the right equipment, since the equipment is essentially the limitation here.
Im sure that most people here could operate a saw in a safe way with a little instruction, but very few here, does actually have a saw of adequate quality and rigidity to be doing it safe.
Once you have the right mashinery for doing theese things, its really quite simple to do it.
Actually there are other solutions to get a bar in the required dimensions. 99% of the manufacturers of metals and pretty much any other material, will cut to size for a most reasonable price.
Magura🙂
With that in mind, I believe that unsafe practice is not to be spread by this forum.
Id personally rather that people go and have a block og metal cut by somebody who's got the right equipment, since the equipment is essentially the limitation here.
Im sure that most people here could operate a saw in a safe way with a little instruction, but very few here, does actually have a saw of adequate quality and rigidity to be doing it safe.
Once you have the right mashinery for doing theese things, its really quite simple to do it.
Actually there are other solutions to get a bar in the required dimensions. 99% of the manufacturers of metals and pretty much any other material, will cut to size for a most reasonable price.
Magura🙂
Magura,
You start sounding like a broken record. I'm having doubts if you are really tool and die maker and not safety inspector.
This is DIY Forum and people want to see what can be done in home environment, without need to contact machine shops.
If this scares you, don't look, but don't try take it away from others with statements like this:
With that in mind, I believe that unsafe practice is not to be spread by this forum.
It's easy for you to say, sitting all day behind your big CNC rig, looking at material being machined through your little safety window.
It seems to me that you come from totally different background and hardly ever did anything with your own, bare hands.
As to "99% of the manufacturers of metals and pretty much any other material, will cut to size for a most reasonable price" suggestion, it doesn't work that well, and if you want to have it done at reasonable quality, you have to wait for days, or otherwise when done on spot, the tolerance is within 0.1" (if even that).
You start sounding like a broken record. I'm having doubts if you are really tool and die maker and not safety inspector.
This is DIY Forum and people want to see what can be done in home environment, without need to contact machine shops.
If this scares you, don't look, but don't try take it away from others with statements like this:
With that in mind, I believe that unsafe practice is not to be spread by this forum.
It's easy for you to say, sitting all day behind your big CNC rig, looking at material being machined through your little safety window.
It seems to me that you come from totally different background and hardly ever did anything with your own, bare hands.
As to "99% of the manufacturers of metals and pretty much any other material, will cut to size for a most reasonable price" suggestion, it doesn't work that well, and if you want to have it done at reasonable quality, you have to wait for days, or otherwise when done on spot, the tolerance is within 0.1" (if even that).
I sold a few of the saws to the metals service center in my town. When they call my house at 11PM with a stuck limit switch problem, they are willing to cut for free.
I suggest that everyone make the same arrangement!
I suggest that everyone make the same arrangement!
Peter Daniel said:
As for my background. I began machining on a lathe...a plain oldfashioned lathe at the age of 6.
During a month work, I operate pretty much any machine you can think of, that be both the manual and CNC variant. So a statement like that "all i see is metal being machined through my little safety window" dosnt have much to do with the reality.
I have unfortunately just seen a little more accidents caused by unsafe practice than good is. I guess you could compare machining to electronics.
In electronics its just easier to tell where the safe limit is, since everybody knows that high voltage is dangerous. As for machining its a little harder since you need a lot more background knowledge to estimate if something is safe or not.
I know for a fact that Uddeholm is represented in most of the world, and they offer day to day cutting and machining service for a most reasonable price. This service is used by plenty of companies for the same reasons as DIY'ers would use it. Most have the equipment to drill a few holes and make a few chamfers here and there, but the rougher part of it is not something most are able to deal with.
Magura🙂
Peter Daniel said:
Yes, mostly a metal saw have different speeds, and theyre all lower than for wood.
Magura🙂
Usually on a 400mm balde (~16") it's 3600 RPM. 24" ~ 2400 RPM. I think it relates more to the cetrifugal force on the carbide tips (silver soldered to the steel saw disk) and the blade body than anything else.
It is absolutely clear that it is quite possible to spin a HSS blade up to grenade status. Small HSS blades ~ 300mm are typically differentially hardened ~ rim ~ 62 Rockwell, hub ~ 50.
From some old research I recall, there isn't a top speed for carbide machining in aluminum. Run what ya' brung as the saying goes. For aluminum milling ~3/8" endmill ~ 28,000 RPM is not uncommon. Spindles, are however, replaced routinely. New coatings are making a big difference.
It is absolutely clear that it is quite possible to spin a HSS blade up to grenade status. Small HSS blades ~ 300mm are typically differentially hardened ~ rim ~ 62 Rockwell, hub ~ 50.
From some old research I recall, there isn't a top speed for carbide machining in aluminum. Run what ya' brung as the saying goes. For aluminum milling ~3/8" endmill ~ 28,000 RPM is not uncommon. Spindles, are however, replaced routinely. New coatings are making a big difference.
Magura said:
It is nice to see the regulation now a days. When I was a little boy my elder brother at the time 16 years of age.. working on a 3.5 horse power motor 13 foot long lathe...was told not to wear gloves when working with wood..well he did...there was no emergency stop switch that he could reach.. he used his solder, neck and body to stop the turning mill then scream for help.. guess what his bones in his forearm where like our twisted pair interconnect in the X-ray...to add more insult he was not insured by the shop owner.. those were the days....
Chris
I was joking a bit on the subject of little (operator's) safety window, but the fact remains that manual work is more and more the thing of the past, and there isn't too many craftsmen left (i'm not even pretending I'm one), who can do much with only basic tools.
But I also believe that those skills could be useful for some eager diy people, and just hiding that info, only because it may seem not safe, is not a good approach.
There are many jobs, and many sports for that matter, that are unsafe, yet people do that because it gives them satisfaction (and pride with things well done). That's why I never strictly adhere to rules and safety practices, because life gets boring pretty soon, when all those rules are being applied. I'm not saying that one has to try whatever I show, I just want to show what is possible. And I usually show how it's done with a reasonable safety margin.
Just to let you know, I cut myself badly only once, when cutting thin sheet metal on a radial saw, without leather gloves. It was a lesson well learned.
I also have an implant in one eye (a plastic lense), when capacitor exploded and hit me directly. That's about all damages I sustained in 20 years😉
But I also believe that those skills could be useful for some eager diy people, and just hiding that info, only because it may seem not safe, is not a good approach.
There are many jobs, and many sports for that matter, that are unsafe, yet people do that because it gives them satisfaction (and pride with things well done). That's why I never strictly adhere to rules and safety practices, because life gets boring pretty soon, when all those rules are being applied. I'm not saying that one has to try whatever I show, I just want to show what is possible. And I usually show how it's done with a reasonable safety margin.
Just to let you know, I cut myself badly only once, when cutting thin sheet metal on a radial saw, without leather gloves. It was a lesson well learned.
I also have an implant in one eye (a plastic lense), when capacitor exploded and hit me directly. That's about all damages I sustained in 20 years😉
True, manual work is sure a thing of the past. It though have proven very usefull to be able to do things manually frequently.
I am of the last...as in very last generation whom learned to use a file and operate a manual machine.
Youre absolutely right that this sort of knowledge should not be hidden from anyone, but it have to be followed by a remark about the fact that anybody I know of have spent thousands of hours with manual machines to gain the ability to get the right result every time.
It also have to be done according to safety practice, else the newcomer have a high risk to get injured before he actually learns to estimate the risk.
Once youve reached a certain level of experience....and Im talking thousands of hours here...years (ive been machining for more than 20 years by now, and its been great the last 7 or 8), you will be able to estimate your own skills and the danger involved in an operation, to make an estimation of the risk involved thats actually worth anythin.
Till such point have been reached, to avoid getting hurt..stick to the general safety practices. When you have gained loads of experience, you can bend the rules a bit.....but not much.
Magura🙂
I am of the last...as in very last generation whom learned to use a file and operate a manual machine.
Youre absolutely right that this sort of knowledge should not be hidden from anyone, but it have to be followed by a remark about the fact that anybody I know of have spent thousands of hours with manual machines to gain the ability to get the right result every time.
It also have to be done according to safety practice, else the newcomer have a high risk to get injured before he actually learns to estimate the risk.
Once youve reached a certain level of experience....and Im talking thousands of hours here...years (ive been machining for more than 20 years by now, and its been great the last 7 or 8), you will be able to estimate your own skills and the danger involved in an operation, to make an estimation of the risk involved thats actually worth anythin.
Till such point have been reached, to avoid getting hurt..stick to the general safety practices. When you have gained loads of experience, you can bend the rules a bit.....but not much.
Magura🙂
chipco3434 said:
In unskilled hands or without the right safety equipment and so forth...yes.
Under the right circumstances....a very safe machine.
Magura🙂
The way most people I know around here have gotten around doing heavier machining at home, is to go for auctions of liquidated machine shops, and buy the old fashioned equipment there. The modern equipment is still expensive on an auction, but the old fashioned stuff is usually fairly cheap, since the industry dont want it.
You get a very nice bridgeport manual milling center for approx. 2000 USD here, with digital readout and feed motors.
To be able to go all the way, you would need a lathe as well, it can be of real simple standard without digital readout, and even fairly small. Such is cheap. Around 500 USD here.
To complete the workshop, a band saw(tape saw?) is a good investment. Again, buy old industry stuff, not the hobby machines that are manufactured for the DIY market. The price is about the same for a good used industrial band saw as for a new DIY saw. Again, attend a few auctions, and youll find yourself with a complete set of machines for relatively small money.
the same works for electronics test equipment, it can be aquired the same way, just got a distortion analyzer, a sine generator, an analog scope and a pulse generator....for less tham 200USD.
Magura🙂
You get a very nice bridgeport manual milling center for approx. 2000 USD here, with digital readout and feed motors.
To be able to go all the way, you would need a lathe as well, it can be of real simple standard without digital readout, and even fairly small. Such is cheap. Around 500 USD here.
To complete the workshop, a band saw(tape saw?) is a good investment. Again, buy old industry stuff, not the hobby machines that are manufactured for the DIY market. The price is about the same for a good used industrial band saw as for a new DIY saw. Again, attend a few auctions, and youll find yourself with a complete set of machines for relatively small money.
the same works for electronics test equipment, it can be aquired the same way, just got a distortion analyzer, a sine generator, an analog scope and a pulse generator....for less tham 200USD.
Magura🙂
Might be best to point out that its a horizontal tilting bandsaw for metal (dunno if it has a technical name), not the vertical woodwork type.
Peter do you accept tolerances of 0.1" in your work? 0.01" shouldnt be much of a problem for you with hacksaw and file(s), also giving you the option to make nice curves and such. And emery cloth will do a good job to clean up the raw filed surface and make it look nice and uniform. Good exercise too! 🙂
Just a point that is my own personal opinion, but some may agree, is that nothing dangerous should be put up on here at all, whether its only a little bit dodgy or not. Its all well and good telling your mates in the pub about how you discovered a new cheaper method to make the parts you need, but you know them and know how safe they are. Any random tom dick or harry could read this, maybe even just the bit where you put about that method, and not all the warnings after. I doubt anyones consience would be too happy if they knew that someone had lost their fingers/hand/more through their advice. Just my perspective though.
Also I'd say the cutting speed is far far too high. Most materials have an optimum cutting speed where you will get the best finish. Whether or not the tool will survive or not is another thing, and for bulkk material removal is fine, but not for finish cuts. From your picture (PD) you can see either where lil hot bits of aluminium have picked up and been deposited on the cutting edge tip, resulting in the metal being ripped out rather than cut. Some cutting fluid may help (to reduce tooth tip temperature) or slow the rpm down.
PS all this is just my opinion, not what i believe to be the ultimate truth
Steve
Peter do you accept tolerances of 0.1" in your work? 0.01" shouldnt be much of a problem for you with hacksaw and file(s), also giving you the option to make nice curves and such. And emery cloth will do a good job to clean up the raw filed surface and make it look nice and uniform. Good exercise too! 🙂
Im sure people don't do this hobby for adrenaline rushes!! There wouldn't be many of us left if that was the case.
Just a point that is my own personal opinion, but some may agree, is that nothing dangerous should be put up on here at all, whether its only a little bit dodgy or not. Its all well and good telling your mates in the pub about how you discovered a new cheaper method to make the parts you need, but you know them and know how safe they are. Any random tom dick or harry could read this, maybe even just the bit where you put about that method, and not all the warnings after. I doubt anyones consience would be too happy if they knew that someone had lost their fingers/hand/more through their advice. Just my perspective though.
Also I'd say the cutting speed is far far too high. Most materials have an optimum cutting speed where you will get the best finish. Whether or not the tool will survive or not is another thing, and for bulkk material removal is fine, but not for finish cuts. From your picture (PD) you can see either where lil hot bits of aluminium have picked up and been deposited on the cutting edge tip, resulting in the metal being ripped out rather than cut. Some cutting fluid may help (to reduce tooth tip temperature) or slow the rpm down.
I thought tools that run at this speed where sufficiently durable and red hot enough to survive this speed, and that this enabled them to effectively melt the material off rather than cut it. I remember seeing this used with a 1mm cutter at 100,000rpm+ that was making a mould for a chocolate box inlay. Quite impressive, but need things like air bearings in the spindle, not really in the diy domain yet...
PS all this is just my opinion, not what i believe to be the ultimate truth
Steve
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