Comments? Bandsaw TPI.

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Little background.After years of "messing with" a small 5"x6" bandsaw (1/2" blade) I finally went ahead and ordered a Wilton 7'x12" saw which uses the 3/4" blade.I have been researching the subject of blade selection for a couple of days.  Lenox has a very informative article regarding blade selection.  I'm really looking for "first hand" experience with different TPI's, variable pitch or not, recommended/nonrecommended brands, ETC, ETC.I know a lot will depend on what I cut but has anyone found a "general purpose" blade configuration that does most cuts at least "well" if not great.On the smaller saw (no name cheapie) I've generally run a 10 TPI bi-metal blade.  Does OK but not great but always attributed the shortcomings to the saw itself.  No matter how much tweaking I do, the cuts don't come close to the PC Dry Cut saw I also use.On my Milwaukee Portaband I use the bi-metal 10-14 TPI variable pitch blades and they seem to be a good all around selection.One of the problems I face (and some of you I'm sure) is the wide range of materials that end up needing to be cut.  One day it may be 2"x2"x1/4" aluminum angle and 30 minutes later its cutting a 2" Aquamet 22 (SS) boat shaft.  Next will be 1" dia x .065 wall SS tubing.  I hope you get the idea.I wouldn't even think of using anything other than a bi-metal blade but beyond that I guess I'm looking for that "silver bullet" which does all things well if not great.Any comments?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:I'm starting to lean back more and more towards the single pitch and finer pitch. That's based on the old "3 teeth in the metal" rule of thumb. Of course I do ninety nine percent mild steel. But if you think about it even something in the 1/8th inch range would need a 24 tpi to meet the above rule of thumb and I've yet to use anything less than an 18tpi. The coarse toothed ones really hog it out quick and porbably are better for aluminum but it just seems like they start developing cracks between the flutes well before they get dull and break. Early death. After the last few 14tpi's died still sharp I've gone back to 18's. Time will tell. The variable pitch never did much for me. Pure opinion but that cachunk-cachunk of the change drives me nuts.
Reply:The blade thats in my saw now is a 3/4" 10-14 TPI M-42 Sarret, but it's been at least 4 years since I bought it so don't quote me on that 100%.I picked it because I needed to cut quite a bit of 2 1/2" 316 SS round bar and some 3/4" 316 SS round. Since then it's just been the generic shop blade until it dies. It's not super happy with real thin stuff (go figure) but does fine with 1/8"+ MS or pipe.I'll probably grab a similar blade to replace this one since I have a bit more of that 2 1/2" SS to cut and that saw is the best I have for that. Anything else I can do with some other saw if required.
Reply:Sundown, you may be looking for too much out of a basic saw and saw blade. One of the factors involved in bandsaw and extremely accurate - square cuts is blade tension. And a small bolt that tensions that wheel is not really the tension that is gonna give you the most accurate cuts. Stay away from any blades that advertise that they cut everything well ! Your machine doesn't have the horsepower or ability to tension the blade to take advantage of these radical saw blades. Decent quality bimetals of single pitch are prob. your best bet. Get a variety of tpi's to keep around and you should be ok. No (1) blade will cut lightweight al angle and then 2" solid ss and then lightweight mild tubing well. It will cut one better than the other but not all of them well. Our saw operators sometimes change to different blades 3 times in an 8 hour shift. Btw, I mean no disrespect against you w/ my comments about saw hp. or blade tensioning ability. Dave
Reply:Generally 3 teeth in the work at a time. IIRC, the Lenox blade info says something like that.Variable pitch lets you 'fudge' the TPI vs workpiece-thickness a bit, but you still can't really get a fine-pitch blade to properly or economically cut through thick work.That means you still have to change blades to get the appropriate TPI for the workpiece thickness.  No "silver bullet" there.Or you get different saws and leave them set up with different TPI blades for different workpiece thicknesses.  Ala Norm and his routers at the NYW.  He doesn't change router bits, he just grabs a different router with the desired bit already in it!    Slightly tongue-in-cheek.  The best laid schemes ... Gang oft agley ...
Reply:Wouldn’t it be easer to go plasma with all the various cutting you’re doing?
Reply:Hey guys, really appreciate the comments.Slanty6:  No offense taken that's for sure.  I know the bandsaw I got won't compete with the big boys. The bandsaw I use at the fab shop I hang out at uses a 1 1/2 blade and is under thousands of pounds of tension.  Now that blade does cut most anything well.  Liquid cooled of course and a hydraulic feed table.  Does a really nice job on 18" I-Beams.Transit:  I do cut a lot with the plasma cutters.  I have two.  A Hypertherm PM 600 and a PM 1250.  They are the workhorses when it comes to cutting sheet/plate goods.  Never been real satisfied with the way they cut SS tubing.  A tubing cutter or the Portaband do much better.  Angle cuts in box and angle are a lot "truer" with the PC or a bandsaw, than they are with a plasma.A lot of times, when ripping a sheet of steel (less than 1/4") I'll use the Milwaukee Metal Cut saw with a Morse blade.  Plasma is faster, but the edge still has to be prepped.  With the saw, I'm done when the drop hits the floor.  If I've got a lot to do, I take it to my buddy's shop (9 miles away) and shear it.  Same thing for precision work.  Instead of trying to do it with the plasma, I'll take it to his shop and use the water jet.  He also has a CNC plasma (10' x 24' bed) powered by the Hypertherm 260 A cutter.  That thing is a beast.  That's what I use when I've got a bunch of multiple cutouts.Based on my previous experience with the smaller saws and the comments I've gotten here, I'm leaning to setting the saw up with a bi-metal 10-14 blade.  I'll also keep an 18 TPI on hand for the thinner stuff.Again, thanks for taking the time to respond.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:Moonrise,That's really not so far fetched in my book.I've got one trim router (a small PC) that stays loaded with a 1/4" roundover bit.You can never have too many routers.  Lets see, at last count.Little Ryobi for 1/4" or so roundover work.DeWalt 1/4" trim routerTwo 1/4" PC trim routers.Two Bosch 1/4" trim routers (really like them)Two Bosch 1/2" (or 1/4") sets.  One set up for fixed operation.  One set for plungeTwo PC (1/2" or 1/4")  One is set up for plunge and one is general purposeOne 2HP PC plunge routerAnd finally, the 3 1/2 HP PC set up in the router table.Believe it or not, they all get used pretty regularly.  And no, I don't have a router for every bit.  Not even close.  Have accumulated "a lot" of bits over the years.I enjoy making sawdust as much as I do mangling metal, and actually am probably a little better at the woodworking.  Been really fortunate to have had some EXCELLENT mentors in both fields over the years.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:You got me beat there! I used to have only 10 routers that I had collected at various times as deals came by and I upgraded or needed a specialty one. I've trimmed back to about 6, 3 of which I might use regularly, but I'm thinking about dumping the one on the router table and just getting a light/med duty shaper instead. Oh and the 1/2" Porter Cable needs to get upgraded to one of the new ones that will take the various bases, I'm thinking the plunge and the D handle at a minimum.
Reply:DSW,I'm an old Porter Cable guy myself, however I prefer the med duty Bosch Variable Speed to the PC in both the fixed base and plunge configuration.  Don't think Bosch makes the D handle though.  Know PC does.The Bosch is also my favorite trim router.Bosch though, doesn't make anything to compare to that PC horse in the table.I've got an older Craftsman Professional shaper (cast iron, 1/2" shaft) that I seldom use.  Probably done more tongue and groove with it than anything else.These new Freud panel door bits (on the router table) are sweet.  They're "real proud" of them too.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.