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Bill Dufour
11-25-2023, 11:43 PM
I need to do something about the wood guide blocks on my 14" delta bandsaw. Previous owner lost the factory metal blocks. I have some worn solid carbide endmills 1/2'" diameter. Just use the round non sharpened ends to touch the blades. Similar to ceramic guides? They have a slight chamfer on the end. Any reason not to use them for the straight horizontal guides. I think there is one at 45 degrees under then table that I will make of steel or bronze. No good way to cut or grind that much carbide.
Bill D

Cary Falk
11-26-2023, 12:09 AM
Spacesge Ceramics makes ceramic blocks for the 14" Delta. You can also google cool blocks for the Delta as well

Mel Fulks
11-26-2023, 2:03 AM
In an employment years ago we were having trouble getting band -saw guides to work well. I took some hard Brazilian Rosewood and
made guides , and they worked better than anything else and ran cooler.

Curt Harms
11-26-2023, 8:51 AM
I used solid surface material for guide blocks. The thing I didn't care for about really hard guide blocks if if they come in contact with the blade's teeth, the teeth come out second best. If the solid surface guide blocks contact the blade's teeth, the solid surface may suffer some but it's easy and cheap to either sand off the damaged portion or make replacements. A second consideration is narrower blades - 1/4" or less. There's not much bearing surface on the blade in back of the gullets. If something is going to get damaged due to teeth contacting the guides I'd prefer the guides get damaged rather than the blade.

John Kananis
11-26-2023, 9:07 AM
I had an old delta clone and I swapped the stock blocks out with a bit of lingum vitae, which worked fantastic. I later bought cool blocks but they weren't an upgrade to the lingum vitae.

Tom M King
11-26-2023, 9:16 AM
Cool blocks work fine on mine.

John TenEyck
11-26-2023, 10:03 AM
I use Cool Blocks as well, but I had good service and performance prior to that with really hard wood. I think Lignum Vitae would be great. As mentioned, metal and ceramic guides will dull/destroy teeth instantly, which I why I use Cool Blocks. You can bury the blade in them if you choose to.

But to answer your question, I don't think I'd use carbide guides unless you only run wide blades and make sure your rear bearing guide will keep the teeth clear.

John

Erik Loza
11-26-2023, 10:17 AM
Just my thoughts: Ceramic is good because it won’t actually wear the blade. Will polish and “de-burr” but won’t change the shape or remove material, like (I suspect) carbide could. Not aware of carbide being used as guide material in any type of woodworking machine. The idea of just using another type of wood seems the most simple to me. Or perhaps some phenolic scraps off Ebay.

Erik

Wes Grass
11-26-2023, 12:09 PM
I regularly saw sparks coming off my ceramic guides. Not heavy enough to ignite anything ...

Bigger issue was nothing was parallel or square. Diamond stone and a fly cutter in the mill fixed that.

I've been too lazy to put some on my Felder.

I'd think shanks of carbide endmills would work well. Nothing but a gut feeling, but maybe the 'line contact' would not damp vibration/ flutter as well?

A number of metal cutting bandsaws use carbide guide blocks. Coolant fed, and hydraulically clamped to the blade on some I've seen.

John TenEyck
11-26-2023, 4:47 PM
Just my thoughts: Ceramic is good because it won’t actually wear the blade. Will polish and “de-burr” but won’t change the shape or remove material, like (I suspect) carbide could. Not aware of carbide being used as guide material in any type of woodworking machine. The idea of just using another type of wood seems the most simple to me. Or perhaps some phenolic scraps off Ebay.

Erik


I use aluminum oxide rods to sharpen knives. SpaceAge Ceramics ceramic guides are made from aluminum oxide. I assume other manufacturers use the same or similar material. How is it that static ceramic guides don't wear blades? Sparks, as mentioned above, sure suggest they do.

John

Dave Zellers
11-26-2023, 4:56 PM
Like others here, I replaced the steel guides on my Delta 14" with wood. I used greenheart and it's been great for many years now. No worries about the teeth contacting them if that should happen.

Erik Loza
11-26-2023, 5:57 PM
I use aluminum oxide rods to sharpen knives. SpaceAge Ceramics ceramic guides are made from aluminum oxide. I assume other manufacturers use the same or similar material. How is it that static ceramic guides don't wear blades? Sparks, as mentioned above, sure suggest they do.

John

I use one of those rods, too. That white ceramic starts at about 1,200-grit, which would require a LOT of pressure and contact time in order to reshape the profile of a bandsaw blade. Unlike carbide, which is specifically used to re-shape metal. Maybe I could’ve clarified better.

Erik

Steve Demuth
11-26-2023, 6:10 PM
I don't see why carbide wouldn't work, but if you'd like to stick with wood, you can get Lignum vitae in small bits (like 1 1/2" square pen blanks, e.g.) for under 20 bucks from a place like Bell Forest Products. Makes great bandsaw guides that will probably outlast the person who puts them on the saw.

Edward Weber
11-27-2023, 11:30 AM
My 2 cents.
Carbide is a bad idea because it's harder than the blade. This defeats the purpose of limiting the blade movement without damaging it.
Vera, or Argentine Lignum Vitae is more readily available than genuine LV and has a Janka rating of 3700, it will work fine.
Unless you cut a lot of curves, a set of guide blocks of "whatever" style, should last years.
Guides are a wear item but only when the blade is forced against them, this should be momentary at best.
If you're wearing guides out too quickly, bearings should be the next step.

Steve Demuth
11-27-2023, 3:45 PM
I agree that Argentine Lignum Vitae is much easier to find than the true species. it'll work fine for band saw guides. It's not quite as hard as the true species, and it's a little less self-lubricating, but it'll work fine for band saw guides. I used waxed hard maple for some time an old machine, and that worked fine without excessive wear too.

And, of course, carbide is harder than the carbon steel in a bandsaw blade, as you say. But so are ceramic guides, which work fine without damaging blades. Carbide is significantly less abrasive than Aluminum Oxide ceramics, and as you point out when you say that wood should last for years, its not like the blades are actually rubbing abrasively against the blocks, if the saw is properly set up. I think it'll work fine, although if I were in Bill's situation, I'd go with wood.

Bill Dufour
11-28-2023, 8:38 PM
Thanks for the responses. I think I will try some 1/2" round bronze rod I have. Much easier to cut and polish the 45 degree angle.
BilL D

John TenEyck
11-29-2023, 3:35 PM
Thanks for the responses. I think I will try some 1/2" round bronze rod I have. Much easier to cut and polish the 45 degree angle.
BilL D


Good approach, Bill. When I read this post, I immediately remembered a post by Jack Forsberg (sp) (Where are you Jack? I miss your posts.) where he made some clever brass guides that fit into the blade slot on his bandsaw. I always wanted to try it but haven't yet. Now that I have a CNC I might just give it a go. Jack's idea makes a lot of sense, regardless of what material you use, for any saw where the lower guides are substantially below the table.

John

Bradley Gray
11-29-2023, 4:42 PM
I think I will try some 1/2" round bronze rod I have

Bronze is good. I knew a bandsaw box maker who used 1/8" bronze to guide 1/8" blades for clean tight turns. His were angled down on top and up for the lower to support closer to the work

Bill Dufour
11-29-2023, 9:34 PM
Round brass or bronze is about half the price of square. Same is true for steel. It has slightly less metal in it and much easier to roll then squares.
Bill D

Richard Coers
11-29-2023, 10:23 PM
My bandsaw blades get dull way before any kind of abrasive guide would cause any damage. I don't run the guides that tight to the blade anyway. There is always a dollar bill clearance between the guides and the blade.