Do you have your part correctly clamped before sawing it?

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Hello folks, this has come up before as an issue in our school shop. I would guess that a few of you out there have had similar experiences. Yesterday, one of the students decided to saw some parts and in the process ended up destroying a rather expensive saw blade. Not necessarily an uncommon occurrence, yet it brought me to put some effort into providing a method of enlightenment for our shop patrons. So maybe some of you out there could use a pictorial such as this to enlighten some of your machinery operators to avoid similar issues. Best regards, Allan Attached Imagesaevald
Reply:+1 for you sir! The shim is a great idea. My saw tends to do the same thing. I'll try this.ThanksTorchmate 2x2 CNC with Flashcut CNC controlsHypertherm Powermax45 Esab ET220i Razorweld 195 MigRazorweld 200ac/dc TigTormach 770, Tormach xstechRazorweld, Vipercut/Vipermig, SSC Foot Pedal Dealer
Reply:Drill and tap a hole on that side of vise to use bolt as a jack.  Most important thing about a saw 9 out of 10 people will never understand how to clamp stuff in it .
Reply:Hello Old Doug, this photograph likely shows, to some degree, the suggestion that you made for helping to provide proper grip while sawing parts that are short or irregular in shape. Best regards, Allan Attached Imagesaevald
Reply:Yes something like that. I would be a wreck if I was around a bunch of guys learning to use a bandsaw. If I had replacements for all the blades that a saw misstreated I would have a life time supply. But some times you have to crack a egg to make a omlet.
Reply:Yeah Doug, I sometimes cringe, other times grit my teeth, still other times practice the art of ZEN, and other times yet, shake my head and walk away to keep from exploding from some of the lack of common sense that is displayed by users of the saw or any other piece of equipment in our shop as well as others. As you say however, you do have to crack a few eggs sometime. A bit off topic, but fairly recently one of the "brainiacs" decided that they would shear a cold saw blade in the plate shear....... I can tell you that the results were not good! The only saving grace on that one is that there are still three other edges on the blades. Best regards, Allanaevald
Reply:When the item is needed and I have no long stock I even have resorted to welding the short little piece inside an angle or channel then clamping on the channel.
Reply:Originally Posted by aevaldHello Old Doug, this photograph likely shows, to some degree, the suggestion that you made for helping to provide proper grip while sawing parts that are short or irregular in shape. Best regards, Allan
Reply:Good post aevald! There are easily as many ways to damage a chuck, vice, machine bed or even hand tools as there are ways to PI$$ up a weld...Some 35 years ago or so I just stuck with the following comment regarding use of machines and tools... "This is what keeps you from flipping burgers with a much simpler tool, or worse, selling pencils on the corner while everyone ponders the DUNCE! Treat it as such."A simple 8" handle on a 6 pitch vice screw provides 4 tons of force with moderate hand tightening, a lathe chuck is very similar. If that isn't enough then check your setup...Matt
Reply:Hello Matt, mechanical energy is a funy thing, it isn't like a snarling tiger or a barking dog. Instead it lies quietly in wait for you or someone else to disregard it's potential and then WHAM it'll give it to you. I have been fortunate enough to work with so many much more intelligent people than myself and I believe I have been able to gleen a bit of their smarts and apply it in a positive way most of the time. This topic may seem rather simplistic to some, yet it and so many others similar to it can mean the difference between a successful day in the shop or a costly or physically painful one. I've got a few more details that I believe apply here and when I get the chance I am going to try to include more. Thanks and best regards, Allanaevald
Reply:At a shop I worked in we needed to cut 10 feet off of a 30foot long 14 inch shaft not easy to get setup in band saw. I had it cuting along nicely some one came out of office and thought they could speed it up it. Slit blade down the center allmost full length never saw that done before. He went back to his deck leaving he to fix it.
Reply:I cut a lot of 9" 6061 round bar using a very large open rake blade. After a few hundred cuts the teeth fatigue and snap off or worse... bend over. A bent tooth will grab the bar and roll it right out of the machine. Nothing like 300 lbs chunk of bar getting thrown out faster than you than hit the e-stop. I normally strap my bars under 24" in length. On shorts I strap using a length of angle between two rounds from the top AND reduce my feed a LOT. Normally a 9" round takes about 6 minutes... if it's a short... I'll let it take 10 or 12 minutes.For smaller rounds I use a piece of angle that I welded a pad to. This goes between the material and the vice. The angle give much more holding power to the vice than the flat edge. I'll post a picture when I get to the shop later.If I'm cutting steels I'll weld the small part to a larger (often square stock) piece and then cut it.If I was a band saw designer... I'd build one with a three jaw chuck for doing round bar.
Reply:As promised here are a few pics of my setup. These setups are proven through trial and error.  I have been thinking about mounting a chain vice on the saw but it has been down my to do list. Pic1 and Pic2, For smallish rounds I made this shoe out of angle from the scrap bin. Literally a 5 minute throw together after rolling some 3.5" bar. It has worked dandy for a few years.Pic3, for trimming short large rounds. This setup worked well.Pic4, I strap the bars once they start to get short, less than 24" or so. Sometimes I'll put the angle iron on top to give the strap some bite. Without the strap the saw can roll a short bar out of the machine.Pic5, shows the blades I normally use. The saw was setup for 6" rounds the lower blade is what I use normally for the large rounds. All aluminum cutting is done at 250 fpm... as fast as my saw will go.If you look close to the lower blade you can see a bent tooth, third from the left. Not planned... just caught it after posting the pics. That is why the blade was retired. Attached ImagesLast edited by forhire; 02-17-2012 at 03:27 PM.Reason: Bent tooth in pic5 ;)
Reply:Nice stuff Forhire, by chance is that saw a DoAll? Guides, vise, and such look similar to the one in our shop, although ours is a C-916 and has some slightly different physical features. Otherwise I might guess a Hyd-Mech. Good looking set-ups and gadgets that appear to suit your needs well. You mentioned that your band speed tops out at 250, I believe ours goes up to 275. We generally run a 4-6 vari-tooth bi-metal blade. Serves the purpose for sawing the heavier sectioned pieces that we generally use in the program. I have an additional image to share on this thread and in this post, hope others will start to include various tid bits as they remember them or happen upon them. Thanks and regards, AllanNote: going to have to work on resizing this particular image as I can't get it down to the 150KB limit hereaevald
Reply:I like the little adapter for doing round things you made there.  When I had to run a bandsaw, it used to drive me nuts.  Tighten the clamp...round bar or whatnot hikes up a skivy!  Tap part down, retighten.    Wish I had thought of that!  Shim I knew, although it doesn't have to be the same height as the part, it does need to be the same width for shorter parts.
Reply:I am going to try to give this another shot to include the image that was too large. So here goes. Allanhttp://www.aws.org/mwf/attachments//...xplanation.bmpaevald
Reply:Originally Posted by aevaldNice stuff Forhire, by chance is that saw a DoAll? Guides, vise, and such look similar to the one in our shop, although ours is a C-916 and has some slightly different physical features. Otherwise I might guess a Hyd-Mech. Good looking set-ups and gadgets that appear to suit your needs well. You mentioned that your band speed tops out at 250, I believe ours goes up to 275.
Reply:That aluminum round looks as if it was on "spin cycle" and our saw is one of the blue ones, as you said, US made I'm pretty sure. I believe ours is around 8 to 10 years old can't remember for sure. Checked out your website, pretty cool stuff. Best regards, Allanaevald