bandsaw blade question

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I am a woodworker by trade and we are doing a winder stair rail with metal balusters.  I talked my boss into splitting the cost of a Grizzly bandsaw to cut the balusters instead of having them sent out. This is the saw: http://www.grizzly.com/products/g9742I have to cut about 90 balusters on each end for a total of ~180 cuts. The material is 9/16" square hot rolled steel bar.I ordered 2 bi-metal, variable-pitch blades.  1 is 8-12, the other is 10-14.Is the 8-12 blade the better one to use for this application?Should I use some kind of oil or wax? (the saw is not setup for oil bath)If so, what is the best thing to use?I am assuming that I can get 200 cuts out of a blade without any problem, or a I being optomistic?Thanks for all of your help.  I have learned a lot from this site and I am really enjoying metalworking.Reece
Reply:I have the Jet version of that saw.  I cut tubing mostly with 18 tpi blade.  I easily get 200 cuts.  I don't know how to gage it since I usually gang cut, like 25 1/2" squares at a time.  I don't keep track of how many time the saw rises and falls, just the quantity.    A couple of years ago I kept a log, in a thread,of the number of cuts I made in 1.25 schedule 40.  I think it was around 200 or more and the blade crack in several places.  I don't remember if it was in a thread I started or not.I don't use any coolant or lube on steel.  If I cut Al or Brass I spray with wd-40,  these metals are rarely cut on my saw.
Reply:I have a similar saw, the cheaper version.  I tried cutting oil.  The chips gathered on the drive and idler pulleys and made the blade jump off.  I quit using them and had no more problems.Just always keep a spare blade.  I can't get the bi metal blades around here, so I am stuck with the cheapies at home repo or the hardware store.  I would pay $30 for a bi metal blade any time.  A few drops of oil on the guide bearings every time you do change the blade keeps em going.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:northazman  I would use the 10-14 blade myself if I had to choose between the two. Mine is 18 tpi also. I only use oil on thick hard metals like 2" SS. Assuming you can cut them all to just one or two lengths, as opposed to each one a different length, I'd suggest gang cutting once you are sure the saw is cutting properly. Cut in small batches first to be safe. Angles will have to be stacked to gang cut as opposed to side by side. I'd also consider setting up a stop block to set your length. This can be as simple as setting the saw near a wall if it dosen't walk while cutting. watch keeping the balusters level when you cut them. A rest or roller stand would help.Good luck and post some picts when its done for us.
Reply:I run the 10-14's all day long on two 4x6 saws, cutting mostly stainless, up to 1 1/2" with no problemDry, with the 10-14, you should easily get your 200 cuts, IF you dont drop the blade on the steel. Lower it gently, and you should get 2000 cuts out of it.But if one tooth goes, then they all will, lickety split. Doesnt that saw have a hole and set screw for a piece of 1/2" round as a length stop?Most do.I agree a stop is the way to go, and a roller stand, if you are cutting from long stuff.
Reply:Using the rule of thumb, minimum of three teeth in the metal, the 8 tpi portion of the variable is about as coarse as you'd want to go for that 9/16ths stock. But I'll bet that 8-12 variable will eat it up as long as you don't get heavy handed and stress the blade. Easy does it with the coarser blades. The 10-14 will work great too and will probably be a little more usefull for all around cutting. Wider range of use that is.
Reply:http://www.mcmaster.com/click onto page 2320 for info on bandsaw blades.
Reply:A couple tricks for keeping the blade clean (so it tracks and doesn't jump on the pulleys) and long lived:When you tighten the blade, make SURE the tension is high enough. Too low and the blade will flex. There are tools like belt tension gauges for this. Some saws have build in gauges (usually a spring and pointer attached to the tensioning mechanism), but check it to be sure the scale is properly set. One of the saws at work was breaking blades and stripping teeth. Finally measured the tension with the right tool and found that the scale (a sticker, basicly) was installed about 1/4" out of position.Take the first several square inches with a light feed to break in the teeth. Then you can move up to the rated feed. The teeth hold up much better.If you can't use coolant (which does help with tooth life by keeping the teeth cool in the cut, but also keeps the blade clean by washing the chips out of the teeth), you can use an air hose. Don't need, or want, much airflow. Set a blowgun to blow over the blade at the inlet of the cut, just enough air to get the chips off and leave the blade clean. You arn't trying to blow them all over the shop, just off the blade. Some saws (older vertical powermatics, for example) came with small compressors built in and an adjustable tube for this. Chips getting dragged in on the blade surface really reduce blade life.Make sure that the blade wipers are in place and properly adjusted on the guide at the cut outlet. These keep the majority of chips from being dragged into the guide, onto the drive, and back to the cut.
Reply:Thank you for your replies.The balusters are S shaped and we do not know exactly where the cuts will be yet.I will be using a stop setup for keeping a consistent length, which will be important for this project.I am now thinking I may try to setup a shop-vac as a chip collector since it seems better to just cut them dry.  That would help keep the chips out of the machine and also provide an airflow across the blade to aid in cooling.I had planned on gang cutting them stacked vertically as much as is practical.  Is it wise to set them up side by side also?  I figured that if I laid them out like that it would be harder to cut, basically like cutting 1 1/2" or 2" solid.  It will also depend on how close we will be cutting to the curved portion of the baluster, it looks like we will be rather close.Another question I had was blade speed.  I am guessing that the slowest of the 3 speeds would be correct for this application.  The speeds are 80, 120, 200 fpm.I'll know more on Tues. when the machine arrives and I can read the manual.Thanks again for all of your help, especially for us newbies.Reece
Reply:My guess is that setting them side by side won't work for you. I think that the curves would cause an offset in length.  I would stack them. I'd probably also bundle them with electrical tape in groups to keep them from moving around. If you are careful they should stay in place. Number per group would depend on how many will fit in the saw vise.
Reply:Another thing that can be done is to keep a spray bottle like a windex bottle with about 2 table spoons of dish detergent and the rest water. Use this to spray on the blad just behind the cut. It helps to keep the blade cool and the chips cleaned out. we use this on the rescue truck with our saws all. It makes a huge difference in the way it cuts and the blade life. There is an air system that you can put the soap water mix in a jug and it will spray a fine mist on the area. Look at a machin shop supply place for a mist coolant system. They are not real expensive.
Reply:Canning wax against the balde every once in awhile when cutting aluminum..Nothing when cutting steel.....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.