Alan Girvan | 13/02/2018 19:21:25 |
40 forum posts 3 photos | Need help with my 6x4 bandsaw. It goes through blades like crazy. It does cut really straight. I would cut a lot of cast iron in sizes from 6x4 and 5inches round. Also mild steel in 5 inch rounds. The blades I have been using are 14TPI. sometimes it just sits on the cast iron and does nothing in the largest sizes. Can anyone help on best blades and number of teeth. Thanks in advance. Alan. |
Muzzer | 13/02/2018 19:42:01 |
![]() 2904 forum posts 448 photos | Somebody on here recommended Tuffsaws. I got a couple of blades from them. The 6x4 uses 1638mm x 1/2" blades and I went for a couple of variable pitch blades - 8/12 and 14/16. I always go for the bi metal blades rather than the 100% carbon steel, as with hacksaw blades. I would guess that you should go for the coarsest pitch and a fine one for cutting thin sections. Are you applying enough pressure? Insufficient would cause rubbing and make the teeth blunt quickly. I found that a 5" round took about 30 minutes and the blade was nice and sharp afterwards. I forget how I judged the preload.... Murray Edited By Muzzer on 13/02/2018 19:45:25 |
Mike Poole | 13/02/2018 19:45:49 |
![]() 3676 forum posts 82 photos | Cast iron is notorious for having a hard skin that would take the edge off the blade in a flash. If this is a possibility you could test with a file for the surface condition of the cast iron. Mike |
Mark Rand | 13/02/2018 20:36:46 |
1505 forum posts 56 photos | For those sizes of stock a 6 tpi blade will work reasonably well. Coarser would be better. 14tpi is so fine that the blade is spending most of its time skating on packed in swarf. |
Clive Foster | 13/02/2018 21:52:25 |
3630 forum posts 128 photos | Allegedly a short (1/2" long?) nick cut through the outer skin where the blade starts cutting helps circumvent the hard skin issue. Presumably because the blade is able to cut immediately and pulls the hard skin away in thin layers with the chips. If the blade merely comes down on the skin it skates around until the skin is worn through. Which is very hard on the blade. Breaking in a new blade considerably extends its effective life. Unfortunately following proper break in procedure is pretty much impossible with those saws. Feed rate and pressure is also an inherent problem with those small hobby saws. The usual spring thing is somewhat non-linear and generally doesn't allow enough feed. Bottom line is you are asking a boy to do a mans work. If you have space seriously consider an older, relatively inexpensive, power hacksaw for that sort of stock cutting. My £100 Rapidor is very effective and would soon have paid for itself in reduced blade replacement costs if I did the amount of heavy cutting you seem to be doing. Clive. |
Mark Rand | 13/02/2018 22:54:19 |
1505 forum posts 56 photos | Posted by Clive Foster on 13/02/2018 21:52:25:
Bottom line is you are asking a boy to do a mans work. Clive.
I'm not sure that that's the case. While I still had the 6"x4" I regularly used it for 4" and 5" stock from aluminium, to cast iron and on to EN24. With a good blade it coped quite well (only blew the motor up once...). But 14tpi blades just aren't going to work on much over 1" diameter. |
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