What's the best blade for for swingmilling?

solodan · December 10, 2007, 03:52:40 PM

Do you have a pic of the bunks? how big are they and what are they made of? are you going to sell them separatley?

Furby · December 10, 2007, 08:11:22 PM

There are a couple different types of 12v jacks out there for those of you looking for that type of diy toe board.

Part_Timer · December 10, 2007, 08:18:53 PM

I take and figure out how much taper is in the log and put that many inches of cribbing under the bunk before I roll the log up onto it.

LOGDOG · December 10, 2007, 09:29:39 PM

I just wanted to mention something to you folks who are swingers or are interested in the concept. I just had a chance to view for the first time today DoubleCuts product video. If you haven't seen it, you owe it to yourself to get a copy. I could ramble on but watch it and you'll see what I mean.

I wanted to mention a noteable difference that I saw that is relevant to what we've been talking about here in this thread. I noticed that his saws do not have vents in the body of the blade. On my 10" ASM blades I had vents in them. I believe they had the ability to put carbide shavers of a sort in there. But we didn't. The only blade that didn't have them was the one I had built. Here's the thing about those vents - you can't run the roll tensioner over them. You can only roll on either side of them. This can pose a problem in the leveling and tensioning process. Just something i noticed and wanted to introduce to the thread.

LOGDOG

Dangerous_Dan · December 10, 2007, 09:41:27 PM

LOGDOG- What are the carbide shaver bits mention?
Fill me in.
And of course - You got a pic?
DD

Captain · December 10, 2007, 09:49:21 PM

He's talking about strobe knives. We've tried them, but they put too much of a load on the mill to be effective in essentially planing the surface.

I use them in our blades, but they are placed differently and are smaller than the "down under" originals. We've made blades without as well. The next batch may indeed be strobeless reduce the cost of the plate, they really serve no purpose to our application.

Captain

getoverit · December 10, 2007, 10:00:25 PM

Just for the record, neither one of my Peterson 10" blades had vent holes in them. They were all solid blades with 1/4" tips.

solodan · December 10, 2007, 10:13:54 PM

My Opteco blades are solid as well.

LOGDOG · December 10, 2007, 11:11:21 PM

Quote from: Captain on December 10, 2007, 09:49:21 PM
He's talking about strobe knives. We've tried them, but they put too much of a load on the mill to be effective in essentially planing the surface.

I use them in our blades, but they are placed differently and are smaller than the "down under" originals. We've made blades without as well. The next batch may indeed be strobeless reduce the cost of the plate, they really serve no purpose to our application.

Captain

:-\ Wish I'd have known that in the buying process.

LOGDOG

doublecut · December 11, 2007, 01:39:29 AM

In our experience Strobes are only really beneficial when stacking blade on one arbor like a gang edger or gang rip. We tried the strobes but were never satisfied with the performance and it robbed to much power . So we never realeased any to the market place.
The saw blade is what any mill is really about. And if they are not working right then it renders the whole mill useless, which most will agree.
Our new D&L swing blades design that we are now currently using have a built in raker system to clear and cut and introduce air. We have found this to be very successful design in our testing in hard woods in south america.
It is a delicate thing to play with a saw blade and when it is not engineered correctly or maintianed it can sure throw a heap of trouble on one's shoulders. I was lucky i had a good teacher with the over 50 years of experience through my family and father.
We are in th process of patenting a Circular blade as we speak that we believe will be the most revolutionary blade ever seen. We hope to have that in 2008.
doublecut

Nate Surveyor · December 11, 2007, 07:44:31 AM

OK, Mr. Double Cut, you sure have my interest!

I was already dreaming of a way to introduce air into the shavings, and it sounds like you are floating way out there ahead of me!

My questions:

What arbor is Doublecut using?

Will you be manufacturing one for the Peterson? (four bolt arbor)

Is your blade design real sensitive to speed, (As in the Peterson apparently turns slower than a Lucas)?

And, another side note: Most swingmills sold in USA seem to be 8" models. (my impression). Will the 180° swinger tend to RE-introduce the 6" model, as the intense ease of double cutting with a 180° model seems to make sense. In other words, a 6" one that is set up perfectly could really be the cat's meow! Most of the wood I cut, I don't need wider boards than 12".
6" mills can use narrower kerf, and it seems to me (in my head) that they would wander less in cutting, making double cutting easier, as the cuts line up better.

Thanks,

Nate

JimBuis · December 11, 2007, 08:00:30 AM

I am running a Peterson 10" WPF with factory blade. I have had no problems WHATSOEVER with the blade.

That is of course unless you want to count the time that I knocked most of the teeth off of one of the blades when I hit metal. ;D Yes, it was my fault.

Jim

LOGDOG · December 11, 2007, 08:55:46 AM

That's good Jim. Glad you haven't had any problems with your blade. How many board feet have you got on that new mill now? She running better with the new sprocket? I keep waiting to see some pics. You know how we are about pics here on the forum.

LOGDOG

Husband · December 11, 2007, 10:06:03 PM

Hi guys and gals.

Just a quick note on the blades, the "slots" are there for a couple of reasons which have not yet been mentioned, we have spent lots on R&D with the blades, types, sizes, speeds etc as you can all well imagine. :P
They serve 4 main purposes,
1 You can put the strobe blades in them, this can use a bit of the hp on the mill, but are good for when you are dealing with the "fluffy" timbers as they clean up the cut and prevent friction which becomes heat which equals loss of tension in the blades as we all know.
2 They also allow a larger amount of water to get to the other side of the blade, if you had a hot piece of flat metal and poured water on one side, what happens? Thats right, it cups, same as a blade. If it cups then it is not running true, again, more heat, loss of tension.
3 The gullets are usually overlooked in servicing by sawdoctors in a rush. When they get rounded the sawdust doesn't get cleared as efficently, then it goes to the side of the blade, those slots will help as gullets and assist with the throwing out of the sawdust when needed.
4. They look cool 8) (just thought tht I would put that one into see who reads this to the end.)

As mentioned, alot of time and dollars but this is why we down under do our blades as such. I would believe that many other manufacturers see the benefits of how and why we do them as such and are doing simular/same sort of thing now. Even the number of teeth on the mills.
Here is a quick story on that.

I was with Carl Peterson helping him at an A&P show with his first mill. We went to do cut number one, all going well, cut two, still going strong, about 1/3 through this log and "TING". First time I heard that noise, (not the last either) we had about 20 teeth on this blade, it left us 4, we had no spare blade so we decided to biff that log, get in another and start again. To our surprise, it cut cleaner and faster with the 4 teeth left.
True story, that is how we came about to using such few teeth on the blades.
So there are times in ones life as we all know that accidents such as ours are blessings in disguse.

Hope I have not bored you.
BTW. We are in disscusions with a couple of blade manufacturers in the USA to do our blades for us there. This way for those Peterson owners, they can purchase their approved blades, from us via USA without worrying about warranty issues etc.

Chris Browne

doublecut · December 12, 2007, 12:10:07 AM

Nate Surveyor :
Yes the new blades will fit any mill. The blade are engineered for up to a certain speed.
But all this will come forth soon.
Doublecut

Captain · December 12, 2007, 06:37:40 AM

With respect to the point that was made about the strobe knife slots dispersing water, we've studied and considered this. The centrifical force and circular motion of the blade dos not allow the water to simply "fall through" the holes. The water does in essence cool the plate when copious amounts are applied, but is is rather like the mud puddles warping hot brake rotors argument to suggest warping of the blade is possible by applying on one side when it is rotating and in the cut. It may possibly if poured on a hot and stationary blade. Water effectively cools by lubricating the cut,and also has positive benefits on some species in carrying/removing chips in some species. It also keeps the fine dust down

. We like water, but mill more often without it for one reason or another.

LOGDOG · December 12, 2007, 09:29:08 AM

I hope you guys don't mind if I disagree on a couple of points mentioned here.

First I have to say that the notion of my water trickle from my ASM dripping on my blade (which is spinning at 3650 rpm +/- reaching the other side of the blade (migrating through the strobes)in either the horizontal plane or the vertical plane is just flat out unlikely. Physics says no. The water lube system was so inefficient on my ASM that in the vertcal plane it wasn't getting water on it anyway. The drip mechanism was mounted to the armature with the blade. In the horizontal position the water would drip straight down onto the blade. But in the vertical position, that armature swings 90 degrees and now (because of gravity) the water still wants to drip down. Only problem - the blades not under it - it's to the side. A better system albeit more expensive system would be a pressurized system similar to WoodMizers Lubemizer which has the ability to irrigate both sides of the blade under pressure in both the vertical plane and horizontal plane. Then of course you'd have to figure out how to do it without it getting in the way while double cutting. Also I believe that with proper side clearance of the teeth to the blade the need for water becomes less.

As to strobes robbing hp. - I didn't have any to spare. With 27 hp I was already underpowered to pull a full 10" cut well. The rule of 5 hp per inch of thickness is hard to get away from. I know some have said that they could do it. If things were right I could do it in the vertical plane if I would baby it. But I'd put money on the table that it's not feasible/ practical with that hp and a 10'' blade to pull those full cuts all day efficiently and have any amount of production. IMHO

Also, a rounded gullet (as slightly round as they may get if you're speaking of the edge of the blade where it meets the profile of the gullet) is not near as likely to be at fault for sawdust spilling over onto the body of the blade as is the geometry of the tooth angle changing and producing smaller chips instead of curls that are easily rolled out of the cut by the blade. If you're talking about the actual shape of the gullet changing then that's some cheap steel in that blade. Also, an excess number of teeth creating too much of a chip load can contribute to over loading the blade.

It's also still a material fact that the strobes interrupt the process of roll tensioning and leveling a blade. See the Armstrong website that I posted earlier in the thread. Note the different approaches to roll tensioning. I don't make this stuff up.

Also, if the strobes or slots were the answer why not have all the mills in your line up using them? It's been mentioned here that some didn't have strobes. Just thoughts that come to mind. Not trying to be argumentative I promise.

Here's my thought on R&D. I think we're it. The sawyers that buy mills, identify things that need to be improved, and either do it ourselves or tell the manufacturer about it and then they address it. Woodmizer is humble enough to say that their best ideas have come from sawyers running the mills and having ideas that ultimately endup on a blueprint and then in production on new mills. For progress to occur though someone has to say, "You know what? You're right, there's a better way to do that. Show me what you've got in mind." I think that's one of the good things to come from this thread. Here's a mix of guys using different brands of machines facing similar challenges posed by the law of physics. This kind of brainstorming can lead to progress.

LOGDOG

woodbowl · December 12, 2007, 09:49:25 AM

Quote from: LOGDOG on December 12, 2007, 09:29:08 AM
The rule of 5 hp per inch of thickness is hard to get away from.

This is another area that concerns me. If a half pass is made, (3" then 6") or (4" then 8") the second half pass that completes the cut takes the same amount of time, the same amount of HP, the same amount of feed pressure and has the same load sounds comming from the motor as the cut is being made ..... right? .... Or does it? ?

Is there a different geometry within the two process that causes either the first or second cut to be theoretically easier and faster to cut?

Nate Surveyor · December 12, 2007, 09:55:01 AM

I know it is more complex, but what about a HOLLOW shaft, with an air & water hole in the center of it. And, a few grooves in the mid portion of the blade, to allow the air and water to escape from the middle, some on one side, and some on the other.

And some 40 psi air pressure, with a little water added in, being fed into it.

Now, we have POSITIVE air pressure and water added to both sides evenly, and making a cushion of air on both sides of the blade. This provides cooling, and better blade tracking.

It might be a hair brained idea, but hey, not all of us are bald! :D :D

Nate

LOGDOG · December 12, 2007, 10:01:53 AM

Woodbowl,

In your illustration the chip load on the second half of the cut should be near identical to the first half of the cut because when you come back for the second half there is only air in the first half. Almost as if it's not there. That triangle I described earlier in the thread would illustrate this because it's only the first 3 or 4 " down the tip to tip line (in either scenario you mentioned) that is actually doing the work. There could be a difference to how it feels if there were a misalignment of the blade present causing the first half of the cut to rub and bind on the face of the blade but it would half to be out of whack pretty good to get that. As to sound, motor load may sound the same but the harmonics of the blade may sould different. Liken it to a couple of pop bottles. One filled 1/4 of the way with water and one filled one half of the way. Each will produce a different sound if you tap them or blow into them. In the second half of the cut more of the blade is covered and sound will be produced and escape differently.

Nate,

I like the idea of adding air to a cut. But then we'd have to address the compressor power issue in the portable application of milling. Stationary wouldn't be so hard.

LOGDOG

Nate Surveyor · December 12, 2007, 10:17:34 AM

2 gallon air tank on the Peterson, with a small compressor, that fills it, and as you enter the cut, pressing the mill, you activate the air valve, by your hand's pressure, to push it through the log. Seems do-able to me!

(Armchair General)

N

LOGDOG · December 12, 2007, 10:18:16 AM

Tagged on to the air idea ...I'm curious to see what DoubleCut has come up with to introduce more air into the cut.

LOGDOG

Steve · December 12, 2007, 01:07:50 PM

I"ve been sorta following this thread so forgive me if my input isn't relevant here. I come from a long background operating Mobile Dimension mills, which are essentially a bigger swingblade mill that doesn't swing.
These mills use what might be considered standard circle sawblades that use inserted teeth that are held it with a tooth shank. It is this shank that does the work of pushing the sawdust out of the cut. Has anyone tried to duplicate this in the swingblade design?
Maybe a just a hardened surface brazed into the gullet would help?
With the MD these shanks would lose a bit of their edge and need replaced periodically and it was obvious then how much they contributed to the sawdust removal.

Steve
???

Captain · December 12, 2007, 04:48:47 PM

Hey Steve, thanks for chiming in. I have run blades on the swingmill with standard "B9" bits and shanks. Honestly, the chips were a bit smaller than I was accustomed to. Feed speeds were a bit slower and harder to push manually, the angle of the tooth was increased about 5 degrees on the ones that I used. I should also mention that the kerf was .030" wider as well.

In an application where I was cutting a lot of nail ridden urban timber, It would be the way to go. I prefer the speed and effort of the standard carbide tip setup to my angle preference, and being more dilligent with the metal detector.

Hey, I found those pics of us on the "big island" again the other day, that was a fun visit.

Captain

Nate Surveyor · December 14, 2007, 06:29:36 PM

Quote from: Steve on December 12, 2007, 01:07:50 PM
I come from a long background operating Mobile Dimension mills, which are essentially a bigger swingblade mill that doesn't swing.

Steve
???

My little brother used to ask mom for a peanut butter sandwich, WITHOUT peanut butter!

We all knew what he wanted was a HONEY sandwich! (he was about 5 yrs old, and the baby of the family, and he ALWAYS got pampered!)

Maybe try one of Captain's blades, as he has done alot of research on this, and give us some feedback.

Right now, I'm running a 9" mill, but have part of the equation solved to bring it back to an 8" mill. when I get that done, I plan to TRY a number of different blades, in various woods, and develop my own opinion. One of Capitan's blades is on my list.

I am fascinated with stuff I cannot have! :D :D

And, I want a swinger that does it ALL!! He he!

Nate