Confused about bandsaw tpi and width for blades from bar stock, cutting fluid choice

Fitzhugh

Fitzhugh

Joined
Feb 5, 2013
Messages
194
We have a HF 4x6 bandsaw at our community shop but the blades are always trashed, time to buy my own and hoard it.
I'm looking at diemaster II bi-metal blades due to many recommendations I saw here, just not entirely sure which.

I will mostly use it to cut blades out of 1084 and 1080+ bar stock - have some in .110, .125, and .1375 thickness. I know about 3 teeth in the cut (with 2-10 OK, according to some), which suggests the 24tpi, but I haven't found lenox bi-metal blades that pitch. I also do see myself cutting some 1/4 and 1/2" mild steel bar stock and some 1.25" cold rolled 1018 round bar in the near future (sooner than I can really afford a second blade).
Can I cut both ends of that range with one blade? I don't care if it takes forever to make the larger cuts, just don't want to ruin the blade.
I'd also like to cut tighter curves with fewer relief cuts when cutting out profiles, so width and thickness come into play. I don't have any sense of how much a narrower or thinner blade reduces blade life, which is why I assume they aren't the first choice.

So, for example, would you suggest
3/8 x .025 10/14
3/8 x .025 14/18
1/2 x .025 14/18
1/2 x .020 24 skip tooth
1/2 x .035 14 skip
(aren't skip tooth only for softer materials? must be tiny, cause that would be the same tooth size as a 48 tip non-skip, right?)

This is purely hobby stuff, doesn't matter if the cuts take forever, especially the thicker ones where it's just gravity fed and needs touching with a candle - or a real cutting fluid if you say it is worth it.

Enco has high carbon blades for $7-8 delivered right now, thanks to the sale. SHould I just buy a coarser high carbon for the small about of thicker stock I'll cut before I can buy a second, coarser bi-metal?

Thanks for any advice,
Fitzhugh
 
Don't over think it. Get yourself a 3/8" bi-metal blade with a tpi suitable for whatever thickness of metal you will be cutting the most. Then make some metal dust!
 
That's the answer I wanted to hear :)

I keep reading about teeth knocked off and have learned not to trust my woodworking intuition about tolerances and tool selection when it comes to metal - started using both a cnc mill and cnc router recently and the need for much greater care in choosing tooling, feeds and speeds, etc. with the mill had me running scared.

Thank you all,
Fitzhugh
 
Darrin Sanders said:
I use the 1/2" 14/18 TPI for everything.
Click to expand...

I use 10-14 tpi M-42 Bi-Metal blades from Sawblade.com for most of my cutting down to 1/8" on my vertical saw, and like them as well or better (and they're less expensive) than the Lenox blades.

Below about 1/8th though, you will need to use 24 tpi blades, especially cutting thin liner material out of stainless or titanium. IMO even though you'll end up stripping teeth from these especially doing titanium, they'll cut for a long time even missing teeth, as long as you don't try to force thick material through them.

Above 1/4" I prefer a courser blade, which I also get from sawblade.com usually a 6-10 tpi works great. To be clear, we're talking about variable pitch tpi, not saying anything between 6 and 10 tpi will work. Variable pitch gives a better cut and some latitude in thinner material.



Trying to cut too thin or too thick material is hell on blades, so try to get in the habit of swapping blades when necessary, it takes 30 seconds or less usually. Also, learn about break-in procedure on blades, it saves stripped teeth and your blades will last much much longer. I can't recommend sawblade.com enough, the prices are great, you get free shipping above $150, they throw in free swag sometimes, but regardless of all that, they have the best blades period. The Lenox Diemaster II's are as good, maybe slightly better for countouring (cutting curves) on verticals, but they're usually twice the price, and personally I couldn't get a difference. I'd put their M-71 Hi production blades up against any other blade on the market for horizontals however(these aren't appropriate for your saw though), I haven't met a blade that can stand against it for cutting solids in a large cut-off saw, especially when you're working with non-annealed nickel alloys.
 
Same here - 10-14tpi for almost everything. I keep a couple 24tpi on the wall for cutting up thin stock.
 
Sounds like I can get away with one blade for most things, just not that thin stock. Oh well :)


Is there a difference in terms of something other than form factor that makes vertical bandsaws handle some blades better, besides being able to take wider ones, or is it just the uses the proper table allows?
 
i really wish they made an 18-22 like back in the day 90% of my steel cutting is 3/32. i have to keep 4 blades in shop 2 wood 2 metal bothe tools get fine tooth and 4-6 TPI blades cause when im cutting anything thats not thin itts really thick as in inches (6 or more on the wood saw and over and inch on the metal saw)
 
I'm having trouble even finding 24 tpi. Spectrum has it but want $30 shipping, even for one blade, clearly set up for larger orders. Northern tool has some but they are unknown brand, looks like northern is horror-freight's twin, only a few less ads on the home page.

I'll have to call around tomorrow (unless anyone knows where?)
24 tpi is the right one to get first in this case.

Thank you all for the help!
 
I see Morse and Viking but no Norse ;)

I went ahead and ordered a 24tpi sold as "Irwin vise grip" brand in 7' 9-1/2", $26 delivered as a memorial day sale ended. With luck it will last until I can buy a decent one.

That was the only length at that pitch, but luckily(??) that's the length needed for this very old shop made bandsaw i found in cl and talked my friend into buying for $25. All hand made, seriously looks like it should be chasing mel Gibson and his dog across the desert before his career meet it's own apocalypse. Dude's landlord's great grandfather made it between the wars, so the story went. Had a whole bunch amazing ago made tools but this was only one that looked at all salvageable. It has a crazy two motor clutch setup for two speed ranges, the one he left on has a serious reductio in addition to the pulley so it goes SLOW. It also has a large steel plate table. It's been tuned up and a few replacement parts machined.

So really it's a race to see if the saw or blade gives up first. Have to remember to add oil to the drip system. Can you say babbett? I just didn't think I'd find even a crap blade i could afford.

I'll go there tomorrow to make a real plunge guide and better bevel jig. I'll take a photo. Hopefully without fingers everywhere.
 
Fitzhugh, Try looking for Lennox brand bi metal blades. Many guys really swear by them as do I. I also buy and use Starrett blades when I find a good deal. Good luck. Larry
 
Thanks Larry, and everyone. In a month or so I'll buy a second blade from sawblades.com or a dm2 from e wherever has them cheapest. You all have been great help, thank you!

I forgot to take a photo of the saw, but used it with a less dull blade I found on the shelf. I tried with the 4x6 and a salt dull blade, but better than the one with flat-top teeth that was on it. That latter saw will need some serious tuning when I get time.

I'll take the photo tomorrow. You're not losing sleep over it I know, but you will have oddly titillating nightmares about it after seeing it, I promise :)
 
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