Reciprocating tool for metal cutting?

[scar]

Hello guys,

My first post/question here...but first a short para about me...

I do metalworking as a hobby - not as a full time job, I have used a Deca 200 buzz-box for the past ten years. Never had a mig though I intend to soon. I have saved up a lot for it cos I would prefer a good unit. I haven't made up my mind yet since I live in Malta and unfortunately we have no dealers here for the big brands. I can buy through internet of course but what about maintenance then? I mostly do stuff for my own around the house. My wife designs ...and i do... erm...try to do them. I admit I am also a tool freak. A large part of the money I earn goes into buying tools - which brings me to my question...

A reciprocating tool...(better known as sawzall) - anyone tried one of these for metal cutting? I'm not talking plasma here but sometimes I find myself having to salvage a piece of metal from a structure and hacksawing is hard work. Grinding disks are great but wear out a LOT. (I used 6 of them for a simple perpendicular cut on a 6-inch I-beam) I have seen clips on youtube of guys using them on demolition sites but haven't yet seen anyone cutting thick metal with them. Pipes, tubes and anything hollow is ok but solid metal???

Had a quote from Hilti - which for me are the best power tools out there (and the most expensive) but this was more than I could pay for..He he.. Now I've set my sight on Milwaukee super sawzall. What you guys think? Will I be buying a useless tool? Should I stick to the simple hacksaw and more grinding disks?

Thanks

 

[rtbcomp]

Welcome to the forum.

I've just Googled "Milwaukee super sawzall" and it comes up with some very interesting posts.

 

[scar]

square holes?

Oh yeah...sorry to bother some more but one other question...

Before welding, when preparing joints, I sometimes like to go a bit further and push one piece of metal all the way through the other, then weld from one side only. (a sort of "mortice" joint in metal) For example, If I have to weld a round rod perpendicular to a flat bar, I like to drill the flat bar first, chamfer the hole from the back, push the round rod through until flush with the chamfered side, and then fill-weld the sloping chamfered side to the round rod. I believe this creates a much stronger joint.

Now recently I heard there are "square drilling drills" which can make a square hole by the simple use of a pillar drill. I can't imagine how this is possible but if true - it's a good thing to have. Anyone knows more about this?

 

[scar]

I've just Googled "Milwaukee super sawzall" and it comes up with some very interesting posts.[/QUOTE]

Hello, Yes interesting isn't it? You can also download the operating manual - which i did - but i got the feeling it's more suited for wood than metal. But then again, why buy one for wood when you could use a chainsaw? Confused now!

 

[rtbcomp]

Oh .........
Now recently I heard there are "square drilling drills" which can make a square hole by the simple use of a pillar drill. I can't imagine how this is possible but if true - it's a good thing to have. Anyone knows more about this?

I remember those from years back on a TV programme called "Tomorrow's World"

I don't think it was broadcast on April 1st, but I've not heard of them since!

Google is your friend http://upper.us.edu/faculty/smith/reuleaux.htm found while Googling "Drilling square holes"

Hello, Yes interesting isn't it? You can also download the operating manual - which i did - but i got the feeling it's more suited for wood than metal. But then again, why buy one for wood when you could use a chainsaw? Confused now!

Use a metal cutting blade for metal, the manual shows it cutting through a steel pipe.

 

[scar]

Wow man, Now that's a lot of info for drilling square holes!! Great read though - and to be honest - if I omit the equations, it's even better.....Just kidding He he.. So these bits do exist then. There's a pic of one which has a tapered shank. Like Morse taper. That would be great since my pillar drill accepts morse taper 3. Now I just have to google where I can find them .......and price. But thanks again. Soemtimes I forget to google stuff and ask instead. If I menage to find them I'll post it for all interested.

Regarding the reciprocating saw, yes you'd have to use the metal blade for metal cutting of course, and cutting through hollow sections would be a breeze I think, - especially thin walled stuff. However since the reciprocating action is only about 2.5 to 3cm movements, to and fro (different models - different brands), something inside me keeps saying it won't be much good on solid steel say 1 inch round or maybe 5/8" square - and that's what I'm after you see. I won't even be bothered to cut hollow with the reciprocating saw since a hacksaw would be more than enough and not a lot of effort either..... Hacksawing 1"+ ---- Ah!! now that's bicep power, sweat and broken blades - and that's in a comfortable sawing position! I know cos I had my body contoured recently around several sharp rusty edges, twisted around a metal structure in a sorry form trying to hacksaw 1" round, using my left hand while holding my weight with my right arm and with almost no room to move the saw. ...I'm sure sometime or another we all've been there. Now that's where maybe a reciprocating saw could have been indespensable. That's why I ask.

 

[rtbcomp]

They seem a pretty friendly firm, try dropping them an email.

 

[shenion]

I have a Dewalt version of a Sawsall. It can cut mild steel up to about 3mm. Then it starts tossing teeth unless you keep it slow. I did a bunch of 1/8 thick angle iron with it and it cost a lot in blades even using better brands.

On thin metal it really chews it up

Sawsalls are great for tearing out walls, jut right through metal lath, studs, nails conduit etc. Not really for accurate cuts.

I had a Milwaukee Portaband that worked great. They are reasl smooth and cut fast.

 

[Weldingartisan]

I've got the Milwaukee V28 recip saw. Good tool, well built and plenty of grunt, great on tube and box. However I would not recommend a recip for cutting heavy steel sections. W/A

 

[hareng]

I have the Dewalt 18V version as well, cost me £44 bare bones some years back. Probably one of the best tools ever bought.
Blades can be had from most places and the Bosch ones fit but not as good as Dewalt.
Choose the right blade for the job, great on laminate ply 81mm thick, need two batteries to cut about 4 ft.
Can cut trees down with long blades up to around 12" to 14" diameter, about 1/2 as slow as a small 14" petrol Still chainsaw!
Pretty good but not accurate on kitchen installs, just hack it out.
Saved a lot of time cutting out a door to install coolant in a 1/2" thick cast steel miller base, approx 12" square 10 mins and three batteries worth.
Great tools.

 

[scar]

Ok so I em...got it... a Father's day gift from my kids. he -he... I guess they won't ask me anymore what I would like when Birthday comes.

So a short review, though I ain't no expert - It's the Milwaukee Super Sawzall 1300 Watts. Straight out of the box it is a bit heavy - but that's holding it with one hand. When you hold it properly with both, it feels very well balanced and you get the feeling that you've got full control over it. The rotating handle is a great asset, as is the quick blade change mechanism.
Tried my very first cut on wood (brand new wood blade) Was friggin impressed. This thing gnaws through wood like crazy. Not a very accurate cut but extremely fast. It was already through it all when I realised I had to release the trigger to stop it working. I've had it for about 10 days till now and won't report anything more on wood - cos it ain't ever going to be a problem. It will cut - always.

Now - metal.... A brand new blade (for metal) - 18TPI and the first angle iron (1.5" x 1.5" x 6mm) was cut after about 45 seconds. I was impressed again but instict told me the blade ain't gonna last long. Till today I had more than a dozen cuts in 6mm with the same blade - and it is well and truly finished by now, but I abused it thoroughly. I cut 10mm studs, an array of L's and T's ...and even a 3" flat bar 4.5mm thick. The blade started changing colour to bluish after the 3rd use but it kept on cutting... so i kept cutting like a mad man to see where it will stop. Not much teeth left but the edge is still somewhat serrated. No use on metal - but will still cut wood at this stage.

I was very impressed that I went out and got meself a 9" long demolition "Torch" blade - 10TPI. ...aaand here trouble started. Found a nice piece of rectangular channel 2"x3"x3mm and before I started testing this new demolition blade I though this is gonna be a breeze. - It lasted about 10 seconds and wouldn't cut anymore. Teeth are all gone in the rear portion of the blade. What the hell? I couldn't believe my eyes!! This was supposed to be a better blade (for demolition) - which was rated as heavy duty and will go through steel, wood etc. A blade ruined in just 15 seconds. I checked the speed settings on the sawzall but all was within the limits specified on the manual.
So I searched google....and found the cause of the trouble... 10TPI. I read that one must have at least 3 teeth on the workpiece at all times during the cutting operation or the blade will snag. AH...well we all learn from mistakes don't we? I was trying to cut 3mm thickness with a blade with teeth spaced out for 10mm thickness. So, I bought new blades from ebay and waiting for them to arrive. One of them has 24TPI - so when it gets here I'm abusing that too - and report it here for all interested.

Till now I've had a couple of painful jerks from the sawzall - but they were due to carelesness from my part. After the initial couple of cuts, I became a bit more confident and totally forgot about the power this thing's got. The trick is to not force it, but rather hold it smooth and steady with light pressure...and wait for the cut.

Must agree with the post above though... great tool and yes - it will cut thick metal sections - with the approriate blade.

 

[Omniata]

I would say maybe use a little oil whilst cutting to help stop the blade jerking and make a smoother cut

 

[Weldingartisan]

scar, has your saw got the adjustable blade rest like mine? Besides giving a rough depth of cut you can vary the cutting area of the blade to even out the wear. W/A

 

[hareng]

Had a butchers yesterday and used a 14TPI Dewalt steel cutting blade when i cut out 1/2" thick cast iron. Still looks fairly good after cutting close on 4 foot.

 

[scar]

scar, has your saw got the adjustable blade rest like mine? Besides giving a rough depth of cut you can vary the cutting area of the blade to even out the wear. W/A

Yes it does. I can slide the blade rest outwards - which will enable me to cut with the front part of a long blade...and it is a very good thing to have but the more you slide the rest outwards, the less stable the cut.

Regarding oil, well yeah. Totally with you on this one. I have a low revs metal cutting machine on a stand in the garage. It makes very slow rotations of the cutting disk and with every revolution, it sucks up oil (with water as coolant) and squirts it all over the place to lubricate and cool the blade. I like it very much, particularly because it is very safe to use. It's not the fastest way to cut metal but definately the safest IMO, and it will go through anything, be it hollow, solid, even Stainless when the need arises. I buy the oil in concentrated state and dilute it with water. Then I use this for virtually all machining operations except tapping. A simple detergent squirt bottle makes a great tool when drilling and yeah... a couple of squirts on the sawzall blade will definately make the blade last longer. The thing is... it's so much fun watching the sawzall work that I em...forget to stop and squirt. ...he He.

Blades still haven't arrived from ebay. Sawzall is getting a longer rest period than expected and me hands getting itchy.

 

[TheJoker]

Hi,

Just seen this thread. I use one of these Ryobi ERS-80V 230V Recicating Saw. I've mainly used it to cut thick alu. Like this:

It works well, but it requires quite a lot of lubrication (which also cleans). A second person to squirt oil or spray WD40 onto the blade would make things quicker. I've used it on plastic and wood too, no problems at all. Still on my first blades (one metal one wood).

Cheers!