pgrbff
Established Member
I need to make 2 35cm straight cuts in 4mm mild steel. Will the jigsaw with bimetal blade work?
Cutting 4mm mild steel with jigsaw
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It should. A fine blade, 18 tpi say, drop of oil and reduced speed is how I would tackle it.
Qualitatively, it's the same as a recip saw and those are used for metal all the time.
It won't be fast and watch out for the blade binding in the cut.
I prefer a narrow slitting disc in an angle grinder if there's a choice but you know your job best.
Qualitatively, it's the same as a recip saw and those are used for metal all the time.
It won't be fast and watch out for the blade binding in the cut.
I prefer a narrow slitting disc in an angle grinder if there's a choice but you know your job best.
That might be a challenge with a jigsaw, personally I have cut quite long lengths of 4mm using an angle grinder and 1-1.6mm thin metal cutting disks.
With care and a bit of practice even 1-2m long cuts can be made quite accurately, you just have to exercise care since the disks are quite fragile and prone to shattering if you inadvertently apply much lateral pressure.
Safety protection is a must!!
If your jigsaw has a pendulum action and is variable speed then you might have some success if you practice on some scrap to find the optimum speed and pressure to apply along with some lubrication to minimise the heat which otherwise will quickly destroy your blades.
Goof Luck!
With care and a bit of practice even 1-2m long cuts can be made quite accurately, you just have to exercise care since the disks are quite fragile and prone to shattering if you inadvertently apply much lateral pressure.
Safety protection is a must!!
If your jigsaw has a pendulum action and is variable speed then you might have some success if you practice on some scrap to find the optimum speed and pressure to apply along with some lubrication to minimise the heat which otherwise will quickly destroy your blades.
Goof Luck!
pgrbff
Established Member
I had a narrow disc blow up in my face last week. Admittedly the first time, and they were Parkside discs at a friend's house, which I confess I wouldn't buy. It's a good Bosch Pro jigsaw, reciprocating and speed control.
I see no reason why it shouldn't work with a good quality blade.- the blade is only a miniature hacksaw blade after all. You're probably better off with no pendulum action though. Use a good quality cutting oil/paste.
Lons
Established Member
Like Sideways I use a slitting disk where ever possible, they cut very fast and if I need a straight edge I clamp a length of hardwood as a guide, it only needs to be about 1/2" thick. As said don't use pressure, it isn't needed and wear a face shield and dust mask. BTW I use Aldi / Lidl (Parkside) disks and never had one shatter so far though they wear down quickly.
I haven't tried them yet but coincidentally I bought a 3 pack of bosch jigsaw blades from screwfix the other week. They are sold as stainless steel cutting and have a continuous small strip of tungsten carbide fixed bimetal style as the cutting edge. Pretty fine pitch teeth are ground into the carbide. If these will cut stainless, they will surely cut mild steel.
I think Phil's right too. Best without the pendulum in metal. Not sure why but I guess because it improves blade stability and swarf clearance isn't a problem with a fine metal cutting blade.
I think Phil's right too. Best without the pendulum in metal. Not sure why but I guess because it improves blade stability and swarf clearance isn't a problem with a fine metal cutting blade.
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AES
Established Member
Don't know for sure, but I'd "almost" bet money that the blades Sideways mentions will do the job. Just keep the feed rate down and use an oil (anything will do, it's "just" to keep the blade temp down).
When I think of a jigsaw I don't think of metalwork, I also like to keep any metal work tool away from woodwork as wood & metal swarf do not mix and also in metal work keep the stainless tools away from the ferrous tools to prevent cross contamination. What you really need is a metal cutting bandsaw or find someone local with one as that makes it easy.
AES
Established Member
@Spectric: Fair enough comment, and certainly basically "correct".
BUT to buy a metal cutting bandsaw "just" to cut (presumably) a 1-off job ???. Personally if I didn't know someone with such a machine, I'd cut it by hand with a hacksaw. It's "only" MS, and "only" 4 mm thick! NOT as much work as people would think (until they try)!
But for a 1 off, I'd happily use a jigsaw - with coolant and the right blade. Doing that job regularly with a jigsaw is a different story - all IMO anyway!
eribaMotters
Established Member
How about going old school and using a senior hacksaw? Last year I had to make a couple of 300mm long cuts in some stainless steel plate. At just under 3mm thick it is thinner than you are working on but not an easy material to work by hand. The cuts were true and a little time draw fileing saw good results.
I had originally tried a cutting disc in my 5" grinder/disc cutter, but it did not like it.
Colin
I had originally tried a cutting disc in my 5" grinder/disc cutter, but it did not like it.
Colin
AES
Established Member
More or less what I was saying above. Lots of people seem rather "put off" by thoughts of "all" the hard labour that's needed to do such a job by hand, but if they try, they're usually pleasantly surprised to find how easy it is really.
Perhaps this'll help the OP:
https://www.ukworkshop.co.uk/threads/hacksaws-how-to-choose-em-how-to-use-em-other-stuff.109936/
AES
Established Member
More or less what I was saying above. Lots of people seem rather "put off" by thoughts of "all" the hard labour that's needed to do such a job by hand, but if they try, they're usually pleasantly surprised to find how easy it is really.
Perhaps this'll help the OP: https://www.ukworkshop.co.uk/threads/hacksaws-how-to-choose-em-how-to-use-em-other-stuff.109936/
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A good quality blade, cutting fluid, the right speed and a good jigsaw and you will be good! Make sure the blade does not heat up too much !
I like the diamond slitting discs for metal, cut quickly with little heat build up and much less likely to fracture. Don’t use normal slitting discs anymore.
Jigsaw would also be fine, given the up and down motion, clamping it to something solid - e.g with the cut line overhanging a bench edge will help with avoiding it vibrating and making an awful noise
A guide would also help with staying straight
Jigsaw would also be fine, given the up and down motion, clamping it to something solid - e.g with the cut line overhanging a bench edge will help with avoiding it vibrating and making an awful noise
A guide would also help with staying straight
glenfield2
Established Member
Shouldn’t be a problem. I’ve cut 4mm steel on my canal boat, including circular holes for chimneys and windows. Bosch metal cutting blades and cutting oil worked for me - the oily swarf makes a right mess over your jigsaw though.
Hi,
Best way if cutting with a small grinder is to carefully follow the line to put a small groove in the steel before returning to the start point and follow the groove gently cutting right through. If you try cutting through and following the line it will wander. I’ve just retired recently after 50 yrs in the piping game and we would cut pipes perfectly square without a need for any trimming before prepping the pipe ends for welding. Even a steel cutting bandsaw is not as accurate if you have a good wraparound for marking the line. Works just as well on plate. A jigsaw will wander I think and will take ages on that
This (linked) shows the way but his safety isn’t too good and a finer line would be more accurate.
I would recommend clamping the pipe/plate down and using too hands on the grinder and a guard.
www.youtube.com/watch?v=bZYD6YlhmLU
MOD EDIT : HIS SAFETY IS APPALLING. AS DAVE SAYS THE WORK SHOULD BE CLAMPED. PLUS SAFETY GUARDS SHOULD NOT BE REMOVED FROM THE GRINDER AND FINGERS SHOULD BE KEPT OUT OF THE WAY. USE APPROPRIATE PPE.
Regards,
Dave
Best way if cutting with a small grinder is to carefully follow the line to put a small groove in the steel before returning to the start point and follow the groove gently cutting right through. If you try cutting through and following the line it will wander. I’ve just retired recently after 50 yrs in the piping game and we would cut pipes perfectly square without a need for any trimming before prepping the pipe ends for welding. Even a steel cutting bandsaw is not as accurate if you have a good wraparound for marking the line. Works just as well on plate. A jigsaw will wander I think and will take ages on that
This (linked) shows the way but his safety isn’t too good and a finer line would be more accurate.
I would recommend clamping the pipe/plate down and using too hands on the grinder and a guard.
www.youtube.com/watch?v=bZYD6YlhmLU
MOD EDIT : HIS SAFETY IS APPALLING. AS DAVE SAYS THE WORK SHOULD BE CLAMPED. PLUS SAFETY GUARDS SHOULD NOT BE REMOVED FROM THE GRINDER AND FINGERS SHOULD BE KEPT OUT OF THE WAY. USE APPROPRIATE PPE.
Regards,
Dave
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Pendulum is like a chopping action so definitely a no when cutting metals
quintain
Established Member
MOD EDIT : video removed
Horrible, terrible, not acceptable on this forum....I request moderators impose a ban on such as this and similar dangerous videos. A lot of you wonderful forum members are experts in your field and innocent people are looking for your advice and when they see the unguarded single hand held cutter working close to the other hand they possibly think "this is how to work" one small slip of that blade etc could so seriously damage the other hand and more, the resultant event would be life changing and possibly life threatening. In my English good manners I seem to think I should apologise for my RANT..... BUT no please, please ban such as this unsafe video.
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A little OTT don't you think ?
I haven't looked at the video (I have now) but did you read the @Dave Moore 's comments before the rant ?
"this is the way, but his safety isn't too good" etc. All the warnings are there.
I have added a note to emphasise his comments pending someone finding a better video that shows the same method but with the work clamped and the grinder properly guarded.
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