Chop Saw Skew... bad saw?

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I finally bought the nicer 14" Milwaukee abrasive cutoff/chop saw. It did okay with 90 degree cuts, but now I'm doing 45 degree cuts and I'm having a problem. The blade seems to bend a few degrees to the right when cutting 45's. 4 degrees exactly on 1.5" square 16g tubing. I.e., as you pull the saw down, the cut sways about 1/8th of an inch away. So you get a useless piece of stock that won't square up.This means I am effectively dead in the water. I have no idea how to get this seemingly simple task done.Will prehaps putting a new blade on help? The blade it has is not old, but I'm thinking maybe just switching the brand will help or something. Running out of ideas here.
Reply:It's one of the down sides of abrasive blade chop saws. The blades flex, especially with angled cuts. If you use an older "worn out" blade that is smaller in dia, you usually get less flex. I've also seen guys use "blade stabilizers" on wood trim saws to help eliminate blade flex. Usually they are a disk of steel with a center hole to match the arbor. They reduce the unsupported blade area and stiffen a blade. The down side is that on an abrasive chop saw as the blade wears you won't be able to cut 100% thru the material at some point and taking the stabilizer on and off will become a PITA quickly.Solutions are another saw for miters...  floor mounted bandsaw, Carbide blade " multi cutter saws" like the evolution and others. ( Note you can not just slap a carbide blade on a standard abrasive chop saw and have it work. The RPM's on abrasive chop saws are too fast for those blades to function.)Another solution is to oversize your pieces and then grind to fit, usually a PITA, but it works if you only need to do a few pieces. A disk sander makes a good tool for precise fitting. That or learn to fill gaps  in your fit up..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:My suggestion would be to try using less less pressure when you are feeding the blade into the cut.  I am not saying this will stop you problem, but I do belive it will help.I offer three choices: Good, Fast, & Cheap. You may pick two.Hobart AC/DC StikMate LXHarbor Freight AD HoodHarbor Freight Industrial Chop SawDeVilbis 20 Gallon, 5 HP Compressor
Reply:DSW i had a porter cable chop saw that i finally got tired of about a month ago after about 6 years  for the same reasons you are talking about no matter what brand of abrasive chop saw you buy or blade you put on it they will only cut so good " 45's suck " i might add  . when i started watching and  reading on all these types of forums i couldn't see why everybody cussed these types of saws until i spent a few years using and cussing one myself so i  read and saw what everyone was saying about the dry cut saws [looks like a chop saw with a carbide blade that cuts metal and uses no coolant but turns slower about 1600 RPM ] i was going to buy a horizontal band saw and keep the PC chop saw then i realized how much floor space  the band saw would take up so already having a stand that i made for the chop saw i looked into the Milwaukee # 6190-20 dry cut saw and weighed my options money wise and decide to  pull the trigger on the dry cut for the sole reason of after what i would have spent on the band saw and gave up allot of floor space that i didn't have and still had the bad cutting abrasive saw that i have grown to hate and let me tell you these things are the S*** they cut perfect 45's with no burrs and doesn't get hot and discolor the material either and i have taken 1/8 in. wide cuts that are perfect "which is impossible with a chop saw ". the only drawback is the $450.00 price tag  and $100.00 or so blades  "haven't had to buy one of those yet " but from what i have read they last a long time if used correctly so if you want to remedy your cutting problems rat hole ya some $$'s and get a dry cut you will not be sorry ! P.S. my cousin and i were half partners on the abrasive saw and i took it back to him yesterday i didn't even want to look at that POS sitting in my garage any more LOL! just my 2 cents  good luck.. Chris
Reply:Thanks for the feedback everyone. Much appreciated.I ended up using a grinder to "fix" the skew. I have a 10" abrasive wheel which I'll try putting on and we'll see if it works (might just be too small). The blade stabilizer is another solution, along with applying as little pressure as possible and taking it slow. If I were to buy a blade stabilizer, what diameter should it be? (say, 8-10 inches for a 14" abrasive wheel?)One day I'll probably just buy the dry cut saw, after I get that 220v MIG setup and a spool gun... right now I'm using stick- pita...BTW, any way to convert an abrasive saw to a dry cut by reducing the RPMs? Dunno if altering the flow of power to it would work... less amps?Last edited by badmajon; 07-04-2011 at 11:40 AM.
Reply:I don't know of an easy way to reduce the RPM's I'm afraid. Turning down the input power on motors to slow RPM's usually is hard on the motor and not recomended. They do make speed controlers for routers that might or might not work, but by the time you add up the cost of the saw, the controler and the blade, I'd bet you are close to what a dedicated saw would cost.I forget where I saw the blade stabilizer's now. It's been quite a few years since I did  a lot of hard core wood working. Big issue is usually making sure the stabilizer is balanced. It wouldn't be hard to turn one out on a lathe if you had access to one.I also thought about something else. Try making a small notch with a grinder where you want to start your cut. That way the blade imeadiately finds a groove to follow rather than skating around before cutting in. I'd try to lay the cut out with a speed square and hit it with a zip wheel on that line then set it in the saw. Still more work, but you might get better results.I use my 2 chop saws simply for fast rough cuts, usually square or where exact fit isn't critical. All critical cuts are done on my band saw or done by hand since I haven't had a production job that waranted a carbide metal saw just yet. If I had to crank out a ton of angles, I'll drop the cash on a good carbide saw in a heart beat..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:thin blades work better
Reply:Then there is 'creep'. Believe it or not the piece you are cutting creeps into the blade while cutting and creates a lot of the added forces that tend to push the blade sideways compounding the bad cut issue. For us that used to do a lot of precicion wood work it's a familiar scenario. Get in a hurry and try to hold it by hand only, slap the piece up against the fence and start your angled cut ==== you could actually feel the held piece creep into the cut at the beginning, ease off during the middle of the cut then pull in again as the blade exits or cut completes. Didn't matter if it was a radial arm, table or chop saw. They all pull the piece in. Maybe only thousanths but still enough to make for an oogly fit up. Trying to counter by pulling back at best you'd come up with a rounded heel or entire rounded cut face. Clamping. Clamping is one of the more important things you can do. Chop saws with the sliding jaw still let the piece creep. That sliding jaw ain't perfect. In wood working guys would put sand paper on the fence and deck and everywhere they could to stop that creep. It's a tuff one to deal with. Go slow and clamp even if you need to make an auxiliary clamp for your saw."The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life." -Theodore Roosevelt
Reply:scribe the angle you want on there, cut using minimal pressure on a piece that is well clamped, then use a sanding disk to true up. I did it for years, but now us a 18" abrasive saw and a carbide dry saw, which are both more accurate.
Reply:I wouldn't have given the abrasive saw back to the bil.While a dry cut saw will do many things well, it's not the best for all uses.  For instance, most ot the dry cut blades are NOT recommended for SS.  Also, cutting rebar with a dry cut saw will, almost certainly, ruin the blade.Letting the abrasive saw "do the work", ie-not forcing the blade will help to minimize the problem.  When I have to do "precision angles" with a chop saw, I generally cut the piece about 1/16" proud and true the angle up using a miter gauge on the stationary belt sander.  Takes a little effort, but yields a nice product.Clamping the work to the saw has been mentioned.  Secure clamping of the work to the saw is ABSOLUTELY CRITICAL when using a dry cut saw.  Few, if any, of the dry cut saws have a substantial enough fence/clamping system to insure the workpiece doesn't "creep" somewhat when making a 45 deg cut.  If that workpiece creeps at all (blade tends to pull the workpiece into the blade), you'll get a rude awakening when the saw binds and generally destroys a few teeth along the way.  To minimize this effect, I will almost always add an additional clamp between the workpiece and the fence.  Have even gone so far as to add a second clamp to the workpiece to serve as a "stopper" to prevent creep.  If you ever jam a carbide blade, due to creep, you'll better understand where I'm coming from.  The first thing you do is go check your britches and then change out the blade because that one's toast.Just a word to the wise.  To be forewarned is to be forearmed.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Originally Posted by Fat Bastardthin blades work better
Reply:What works best for me on my Makita chop saw is using my visegrip C-clamp to hold the piece solid against the fixed fence.                                     MikeOl' Stonebreaker  "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw
Reply:I gave up trying to mitre descent angles with anything but my Haberle cold saw.  yeah, they cost way more money (mine was $280 at auction, plus 60 for a pair of reconditioned blades, and about 8 hours spend cleaning her up) but the payoff in correctly fit up angles is almost priceless and has saved me TONS of time.
Reply:I cut Mitres on my Dewalt Cop saw just fine-What I've seen with most people having problems with a chop saw is that they don't adjust the fence to make sure the blade is coming down on the material in the correct spot- causing the blade to wander. 90˚ as well as 45˚Ed Conleyhttp://www.screamingbroccoli.com/MM252MM211 (Sold)Passport Plus & Spool gunLincoln SP135 Plus- (Gone to a good home)Klutch 120v Plasma cutterSO 2020 benderBeer in the fridge
Reply:The supplied Milwaukee blade flexes quite a bit and was unuseable for meI found the Dewalt ones with the very visible fiber reinforcement to be much better.As mentioned before light pressure helps a bit and unless you are doing ultra precision stuff youcan figure out a way by maybe cutting a slightly tighter anglefor example I cut just slightly more than 45 and what results is that one side is 45 and the other is slightly over cut but will suffice to fit upsometimes if I am lucky depending on how I cut the pieces they will offset each other and fit good.MM 180
Reply:For light weight tubing try moving the clamp to a point where you are starting with the blade on top of the tubing, instead of the edge. For me this results in a more accurate cut. Takes longer, but the angled edge of the tubing does not push the chop saw blade at an angle.