Whatcha Sawin' 2025 ??

[Magicman]

I returned to a many times repeat customer this morning:


15 logs but about half were "too far gone".   Very good help.  


SYP is some purdy stuff!!


964bf of mostly 1X12's with eight 8X8's not shown.  We called it quits when we had to slab too deep to reach the small amount of good wood.  He was happy and so was I.

I think that my next job is hardwood. ??

[Old Greenhorn]

Well, you can check current (amps) with many multimeters, but you have to run the  feed through the meter and change the connections in the meter, meaning you have to disconnect the line and connect the lead to the meter and the other meter connection goes to the terminal. However, most of the cheaper meters we all use do not allow for this. Those more expensive meters that do will have a low limit on the amount of current they will handle before burning up. If you have a nice Fluke meter, it might handle 5 amps or a bit more. Less expensive ones only handle an amp, maybe 5 at best.
 For serious current to run a motor or something you need a clamp on ammeter such as MM showed. Those aren't cheap, but they can tell you an awful lot. They worked by induction and sense the current traveling through the conductor. The ones I used always belonged to my employer because of that cost and troubleshooting was not mt main job. If I blew it up, the boss ordered a new one (I never blew one up). I may have an old one around here somewhere I could use in a pinch.
 This is why I suggested a infrared thermometer earlier, it's a lot cheaper but still lets you detect heat rise in a conductor.

[WV Sawmiller]

You are not going to get an amp reading with a multimeter. 

 
Reading a circuit's amperage is a whole 'nuther ball game.  Here I am reading the voltage with a multimeter and the amperage with an ammeter.

The power feed motor does not operate with a varying voltage but with a varying pulsed voltage controlled by the circuit boards, etc. that Ted referenced to above.

Lynn,

  Thanks for the semi lesson. I now know I need to get an ammeter but where do I need to place it to get a reading and what is normal or excessive amps? The feed motor has 2 wires to it that look to be about 10 gauge wire. Do I need to encircle the wire at the motor or somewhere inside the control panel? What would be acceptable and what would be excessive amps? 

[Magicman]

As I mentioned earlier, the power feed motor does not operate with a varying voltage but with a varying pulse voltage.  All of the tests that I have done with the techs at Indy have been with a test lamp not an ammeter.  I have never had a power feed problem.

Howard, I am not knocking you for anything that you did or did not do.  I still feel that your ongoing problem has not been with the components that failed but with a dirty connection that was causing the components to fail.  Put a new component in and it will fail just like the previous one did.  That center wire could have been that dirty connection.  

As Tom mentioned, "tight is not good enough".  It has to be clean and tight.  I know that you eliminated one problem, I just hope that it was the problem. 

[SawyerTed]

If I'm not mistaken, the feed motor is a 1/2 hp 12 volt motor.   Full Load Amperage would be between 35 and 40 amps.  It should not operate at full load very often.  Full load would be nearly or completely stalled.  So amperage drawn should be considerably less. 

Not every clamp on meter like Lynn pictured measures DC amperage.   When looking for one, check for that in the specs.  About all measure AC amps.  The clamp on types can measure several hundred amps.  We used to have to measure amps with the meter inline as Tom was indicating.  

There was mention of a bare wire leading to the motor.  That could easily be the source of the high amperage/heating issue.  Intermittent contact to ground might not have been enough to trip the breaker.  

Did you have breaker trips prior to finding the bare wire?  

[WV Sawmiller]

   I found the bare wire while changing the motor and taped up the spot. Yesterday I cut and properly replaced the terminal end. Prior to replacing the motor I was sawing an oversized log and the breaker was tripping constantly then on the smaller log following my feed became too erratic to run. The erratic feed turned out to just be a worn out feed belt as far as I can tell as a new speed controller (Potentiometer) did the same thing but the new belt stopped it.

   My new switch I ordered Thursday from Atlanta came yesterday but I'll try the repaired on till I feel it is not working right. 

   I have replaced and checked the connections and don't know where else to look if it comes back other than feeling for a hot wire somewhere.

[SawyerTed]

Howard, all the clues say you have gotten to the bottom of it.

[Magicman]

There is a shunt that you can use that is wired in series with the circuit.  Your regular multimeter reads the small voltage drop across that shunt which is then converted to amps.

The problem with the circuit in question is that the driver is variable and creating a model for the testing duration could be a challenge.  As I understand it, the current draw for that motor should be fairly constant but the supply voltage is pulsed which varies the speed.  This would be very difficult to test with our normal test gear.  It would probably take an oscilloscope.

Howard, I am hoping that you have isolated your problem with the overheated crimp connection but if not you may have to resort to a thermal heat gun/sensor that someone suggested.

[Dave Shepard]

On my Super, Wood-Mizer told me they use PWM, or pulse width modulation to control motor speed. They basically increase or decrease the amount of time that the motor is grounded, many times per second.

[Magicman]

Exactly.   

Now if there is a bad or compromised connection in that circuit going through the motor, the result will be heat.  That circuit includes both the 12V hot and the pulsed ground.

[SawyerTed]

Won't polarity have to switch for reverse operation?  

[Magicman]

Yes, reverse is reversed polarity and direct with no speed control nor reduction.

At one time Wood-Mizer offered different size sprockets which would speed up the reverse with hardly any affect on the forward operation.  I doubt that they still do.

[SawyerTed]

So a short to ground would only be a short half time?  Only in forward or reverse depending upon which wire was bare.  

[doc henderson]

breakers and fuses are designed for a designated voltage and designated amps.  so, a blown fuse or thrown breaker can be a down and dirty way to say you are pulling too many amps, especially if it is repeated.  and do not think you must have a bunch of bad fuses and bypass it cause you'll burn up other stuff, letting the smoke out of the wires.

[WV Sawmiller]

   Y'all keep talking them foreign languages like reversed polarity, variable pulse rates and such and keep giving me a head ache.

     Tom is the only one who has provided a suggested tool I may know how to work with as an IR heat gun I can point at a wire or connection and get a reading. I still don't know what is normal or excessive but I guess if the difference is a lot more between off and running I need to check connections there.

Doc,

    Remember Murphy's Law: "A $500 picture rube will protect a 5 cent fuse by blowing first every time."

[Old Greenhorn]

Well Howard, we can explain it to you, but we can't understand it for you.

To really get good information from the more advanced diagnostic tools you need to have a working knowledge of electricity and electronics. Understanding the difference between current and voltage being a very basic building block, then wave forms (DC vs AC) and pulsed waves. Yes, it gets fairly complicated and I have forgotten much of what I used to know already.

But this is why I suggested a temp test device. In normal operation there should be very little, if any temperature rise in any of the conductors. Seeing 10° or more is a warning sign for sure. Also, it will not always show the heat rise in one spot, it could be along the entire length of the wire. SO it's never simple. With a thermometer, you are looking to 'see what you can see' and it may add another piece of the puzzle. If you had, or could borrow, a small thermal imaging camera (TIC), that would likely show you a lot more. These are expensive, but the price is coming down and a lot of mechanics are now carrying them in their tool boxes. Even Snap-On is selling them.

 I am with the other guys here, I think you have it fixed. Just keep a close eye on things for a while.

[WV Sawmiller]

Well Howard, we can explain it to you, but we can't understand it for you.

That's just a mean thing to say - even if it is true.

[Digger Don]

Howard, I'm with you on this one. I can read the words, but they just as well be Greek. I do know though, like Doc said, if you let the magic smoke out, it won't work.

[doc henderson]

I sawed some oak for a guy who farms and has a business for lube to go on some part of a field irrigation system.  he brought 3 logs that his grandfather on his dad's side planted, and his dad was maybe 5 at the time.  got a cookie cut off for a family tree table.  got some 3-inch slabs and some 6 x 6 and 4 x 6 beams.  the longest tree was half inch under 21 feet the theoretical max for my mill.  I trimed the ends back as they were at a wonkey angle, and you have to be sure when you come out of the wood that you are not going to catch an angled piece of the log going up and damage or break a blade.  He was happy as I had it all banded and on pallets. 



barely fits




I do not think this is even a log.  @YellowHammer





6 hours at 100 bucks and hour and he brought two more logs when he picked these up.  well, they do not roll easily, but the weird ones pay the same per hour.

[Wlmedley]

What kind of wood is that Doc? Grain looks like red oak but the ends look kind of strange to me. I suppose it's some sort paint .

[doc henderson]

He did not know but I think it is red oak.  and yes, a yellow green paint left on the ends I did not trim back.  looked a bit like mulberry at first.

[Old Greenhorn]

That's just a mean thing to say - even if it is true.

Howard I assure you there was no ill will intended in that statement, it's just a fact. Truthfully I am as guilty as anyone of trying to 'hit above my weight' many times. My Pop would talk about motor phasing and field shapes as well as capacitive starts and such like that and it remained to this day a total mystery to me. He understood that just as easily as the alphabet, because he was there was these things were developed. We all work and understand at different levels is all I was saying.

 A related story: I worked in a shop one time and we and a CNC machine go down. It was running 2.5 shift production and we had a daily delivery quota. I wen tout and did the troubleshooting and narrowed it down to a bad pulse coder. The machine was older, the part would have to be made by the manufacturer in Japan and shipped. They said 6 weeks. This was unacceptable. I had friends at the company that made the machine and they pulled schematics for me while I opened up the pulse coder. Lots of tiny surface mount components that looked like little square cubes. No ID's on anything. The guys reading the schematics could only tell me this questionable component I found was a capacitor, but not the value. SO I went to radio shack and bought a package of about a dozen different small capacitors. I was pretty sure none of this would work, but I had to try, we needed the machine badly to get back up. I took a shot and picked one value at random and replaced it. The dang thing worked and the machine was back up and running after about 6 hours of work. I walked past the boss on the way back to my office an let him know the machine was up and producing again. He asked me what I did to fix it and I just said that I could tell him, but he wouldn't understand it. He wasn't happy with that and wanted all the details, he wanted to know how I always managed to figure this stuff out when nobody else could. So I sat down and gave him all the details including my thought process. When I was done, he looked me straight in the eye and said "You were right, I have no idea what you are talking about or how you figured it out, I am just glad you understand it."

 Everything is relative to one's experience Howard.

[Resonator]

Nice milling Doc, you definitely get the "big log on the mill" credit for today!

I'm not a hardwood expert by any means, but if I had to guess I'd say that's burr oak and not red oak. Note the thick deeply furrowed bark, and the end grain kind of "blurry" compared to red oak. If I'm wrong, I'm sure I'll be corrected.

[WV Sawmiller]

   Well, cyberspace ate another post.

    I went out and bucked 2 small tulip poplar tops into a 12', 8' and 2- 6' lengths. I needed a 12' 2X6 for a repair project on my barn and the rest is just salvage/stock.



I had a disinterested audience about 40 yards away. She ignored me even when I cranked and ran the mill. I spotted another doe with at least one fawn up in the woods 20-30 yards away a little earlier.


   I did not finish the last 6' log but got 118 bf out of these. The 6' boards have a lot of purple color. I smelled some belt smell and found the drive belt was loose and even jumped track once. I tightened that and ran the mill with the control panel open and would feel of the wires and terminal connection points but they all felt cool to the touch with these small logs. The cross bar on on the forward/reverse did seem to warm up in use but I don't know if that is normal or not.

   In the background you can see 2 aluminum 10' rollers I bought last week. I plan to mount one to two saw horses and build a trough to load slabwood and edging to saw off to kindling and small firewood lengths.