GUIDE BLOCK VS ROLLER AND KINKED BLADES?

Dana Stanley · March 06, 2019, 08:37:34 PM

So I have two questions and or concerns! The first is about blade guide rollers or block, and which is better and why. I have a woodland Mills hm126, it has guide blocks. I am wondering if I should or even could convert it to rollers.

The second is about blades that have a kink in, and can I just hammer it out, which seems to me to be the thing to do, or am I looking for trouble? I was having a little trouble setting the tracking on my mill at first and I kinked two blades, and cleaved 4 teeth off of one blade. I ran the one with the missing teeth, and it cut ok, but obviously not the smoothest looking cut. Then one of the kinked ones I tried and did a whole log with it ,but I plan on working on it more before I use it again. Made the same skip marks as the missing teeth!

I guess I have a 3rd question, anyone ever weld teeth onto a blade? I think I can do it, but I'm not sure how they will hold up. I thought I might take an old sawzall blade, cut some pieces out weld them onto the blade, then regrind the teeth. Maybe weld the strip of all 4 teeth at once, the then grind and set teeth into the patch. kinda like a crown or a partial that a dentist would do! ;D

Chuck White · March 07, 2019, 06:43:08 AM

I sharpen a few blades for friends, and I've received blades that were kinked, and I layed the kinked part on the bench and hammered them out with good results!

Welding on the blades IMHO would be a job for the really advanced welder.

Dana Stanley · March 07, 2019, 07:22:58 AM

Quote from: Chuck White on March 07, 2019, 06:43:08 AM
I sharpen a few blades for friends, and I've received blades that were kinked, and I layed the kinked part on the bench and hammered them out with good results!

Welding on the blades IMHO would be a job for the really advanced welder.

I was a professional welder for 6 years. I built trailer dumps from scratch. Chassis and tub, fab and weld. Then I welded aluminum for signs, and fabricated signs. I would be better off with to tig weld it, and I'm not sure my tombstone welder will go low enough. I know I can mig weld it ok, but will it hold up? I also know people braze blades, but is that the best way. I believe the machines that weld blades together are elecro-welders, like a big spot welder. Thanks for the reply, I am sure I can fix the kinks, just don't know how much I shortened the life, and if there are any special tricks to it.

millwright · March 07, 2019, 08:03:11 AM

As cheap as blades are I don't know how I would feel about working around one that had teeth welded in it. You are pretty much in the line of fire if one breaks off.

Southside · March 07, 2019, 08:27:07 AM

Seeing how much a band flexes and the that even a factory weld can and does fail in a band I agree that I would not want to be around welded on teeth. If that worked well I suspect some of the band manufacturers would offer it as a premium product.

The question you have to ask is if the band fails what is at risk, even inside of the guarded areas, and do those parts cost more than the savings of not replacing the band?

CCCLLC · March 07, 2019, 08:46:24 AM

Southside has got it right. Flexing thousands of times around the wheels,welds need to be tempered and annealed to perfectly match adjoining material, otherwise stiffer area does not flex as much and adjoining area takes up the slack, leading to failure. Not worth the time, considering the cost of blades and safety.

Chuck White · March 07, 2019, 04:28:54 PM

Another thing to consider!

When a blade cracks, out at the edge of the crack the gap in the metal is wider than at the base of the crack!

Unless the two edges are forced back together, once welded the blade will be crooked and won't run without a noticeable jump as it goes around the wheels and bladeguide rollers! :-\

Woodpecker52 · March 07, 2019, 04:58:43 PM

Not worth the risk, deep 6 the flawed blades and as far as rollers or guides I like rollers, they fit tight and keep blade from flexing. I have guides on my shop bandsaw and use cool resin blocks but they still have gaps in them and allow blades to flex more.

Dana Stanley · March 07, 2019, 06:39:10 PM

Ya, I am pretty much convinced that for the $20.00 for a new blade vs the risk, and time to repair, it won't be worth it. It was the blade that came with the mill, a lenox, and it did cut very smooth. O well. What about guide rollers vs blocks? Any pros and cons?

btulloh · March 07, 2019, 06:56:46 PM

Probably no argument that rollers are better than blocks. That being said, I have the HM126 with the original blocks and don't have any problems. I have always run my blocks with a little more gap than is usually recommended, even on my vertical band saws. Some people change their blocks to rollers.

bandmiller2 · March 07, 2019, 07:24:22 PM

As with anything bandmill the proof is in the boards, if their straight and of even thickness all's well with the world. I have used blocks on a WM LT-70 and they worked fine my own mill uses rollers. I think most would prefer rollers, Cooks sells good after market rollers for the conversion. Frank C.

Southside · March 07, 2019, 07:55:39 PM

Just to add to the confusion my Super 70 has rollers AND guides.

Dana Stanley · March 09, 2019, 07:54:43 AM

Well I haven't found any negative articles on the guide blocks, so I guess I should stick with them. Not sure why I think rollers are better. Oh well. So I ordered 5 more blades from WM, once I bang the kinks out of the two, I will have 10. That should be plenty for a hobby mill. This time I got the double hards. Now I'm rounding up parts to build the trailer. I just got 6 jacks.

donbj · March 09, 2019, 01:40:48 PM

Personally, I wouldn't use a kinked blade. The kinked area has been bent well beyond what is intended imo. Being a hardened spring type steel I think it's integrity is compromised. It's strictly a safety issue for me.

mitchstockdale · May 24, 2019, 01:52:39 PM

Quote from: Dana Stanley on March 07, 2019, 06:39:10 PM
Ya, I am pretty much convinced that for the $20.00 for a new blade vs the risk, and time to repair, it won't be worth it. It was the blade that came with the mill, a lenox, and it did cut very smooth. O well. What about guide rollers vs blocks? Any pros and cons?

Missing teeth on blades isn't that big of a deal...I chowdered up the factory blade on my HM126 pretty good when I first started running the mill. That blade is still in my regular rotation that get sharpened and works fine. I think if you can weld adding a set of rollers with an extendable arm would be great upgrade for the HM126. I was having some issues last evening with wavy cuts around knotty areas and noticed my guide blocks where about 1/8" on each side of the blade...adjusted the guide blocks and cuts nice and straight now.

luap · May 24, 2019, 05:52:53 PM

Quote from: Dana Stanley on March 07, 2019, 07:22:58 AM

I believe the machines that weld blades together are elecro-welders, like a big spot welder. Thanks for the reply, I am sure I can fix the kinks, just don't know how much I shortened the life, and if there are any special tricks to it.

We had such a welder in our shop and anybody with a little training could prep the blade material and weld them together. But without The proper annealing, tempering technique, they broke immediately. It took lots of practice to master this process especially with more than one band size. We had 100 ft rolls of blade material. These were for metal cutting saws but principle the same.