Sawmill Maintenance/Repairs

[ladylake]

 
Unhook the computer setworks for sure.  Steve

[barbender]

On the Ponsse machines, there was a pre-welding procedure. You turned off the master switch, disconnected the engine computer, and then there was a grounding switch that was engaged. I think the grounding switch grounded the fuse panel, if you forgot it engaged there was a big 300 amp fuse that would cook when you turned the master switch back on😁 This is just an example of how managing welding on a a machine with a lot if complex electronics.

[Beavertooth]

Throttle pin on my 62 cat engine has worn on the inside where bolt from throttle solenoid runs through the middle of big part of it and also the small pin that actually sticks into the throttle on the motor is worn near bout into.(can't see that part very well in the picture).  So when the solenoid pulls the throttle into position it was a good bit shy of full throttle.  Just something that had been a gradual thing happening and I had not realized how much slower my engine had been running compared to what it should have been. Solenoid not engaged in pictures.  Got it adjusted and a new one on the way.  

 

 

  

[Magicman]

Good catch Craig. 

I will try out all of the maintenance items that I have done next week with a bit of ERC sawing.  I have not sawed since August 23rd.  ;D

[Beavertooth]

Having someone change my head gasket Monday. I still have the old style head gasket. 

[Beavertooth]

Lynn I haven't sawn since then either.  Must be something in the water. 😂

[Dan_Shade]

I had an interesting thing happen a few weeks ago:

I've had a lot of problems with my alternator eating belts, I used a 17350 Belt most recently, not sure how many hours it lasted, but i'm guessing 25-30 or so...

But anyways, with all of the shields on and off over time, I lost a bolt for the alternator shield.  I had a single bolt holding the guard on the bottom side of it.  After finishing a cut, my blade did not disengage when I turned off the auto clutch switch.  I first thought that the switch had failed in the "on" position.  After troubleshooting for a bit, the alternator shield was getting hung up on the drive belt shield, not letting the engine set back down to disengage the belt....

I have a tendency to just patch up things "good enough" when on a jobsite, but never seem to have time to complete the repair properly after the fact.  I suspect that I'm not alone, and this sort of thing gives old equipment a "quirky personality" that we tend to learn to address over time.  After all, a leaky roof is only a problem when it's raining.   

One of the other "quirks" on my mill is that the far end toe roller hydraulic lever doesn't properly actuate the microswitch that turns on the pump, so I have to pull two levers at a time to make it work.  

Who is it that said "We'll keep going like we are until we can't go any further."?

[moosehunter]

Beavertooth, last year my idle adjust screw bracket cracked. It was hard to see but my idle kept getting lower and lower. I was on a job so I adjusted it up. Pretty soon it was way low again. Took putting on my reading glasses to see the crack. Got through that job and welded it up when I got home.
mh

[Magicman]

One of the other "quirks" on my mill is that the far end toe roller hydraulic lever doesn't properly actuate the microswitch that turns on the pump

I would think that you could tighten that rocker up a bit.  (This should be the thing to do.)

You may could even move the microswitch slightly which could make it actuate/energize quicker.  I realize that we are talking thousandths of an inch, but...

[Dan_Shade]

I'll adjust it next time I'm in the hydraulic box. 

Dan 

[Stephen1]

I was on a job last 2 days and yesterday the mill acted up sawing going forward. stalling and sticking.
first thing I did was open the drive cover, belt was a tad loose and full of sawdust. Cleaned it out adjusted the belt and bak to sawing. Too simple , still acting up as I had to play with the potentiometer and getting surges and then of course wavey cuts. I had just replaced it back in June at a cost of $100, a big jump from $35 I used to pay to replace it on the old 93 mill. So being frugal, I didn't order an extra replacement like I should have. 
But I'm thinking yesterday, I have a spare in the kit, take the cover off to replace it and realize the one in my kit is really the old one and not a new one like I was hoping. 
I called WM, Yes we some in stock, yes you missed shipping today, yes we can leave it out for you to drive over and pick it up. I also ordered another box of blades. 
Cathy would you like to go for dinner tonight. Yes that would be nice Steve. I didn't tell it was 1.5 hr drive for dinner until we left.  ;D ;D
We had a nice drive through the countryside and a very nice dinner. 

[Magicman]

 

 A guide roller stopped rolling this morning.  I felt a sorta roughness when I put the blade on but it was turning freely.  Freely, but not for long.  It stopped turning before I finished the first log.  That guide is only about a year old and was only slightly smaller than the new so I will replace the bearing and give it another chance when either needs replacing again.

[Dan_Shade]

I had that happen once, I tried to limp it through because I couldn't find my replacement bearing. 



 

 


I later found it on the dash in my pickup. 

[Magicman]

I have a few more new complete guides plus at least one replacement bearing kit. 

If/when I need to get rid of some $$ before the end of the year, I stock up on whatever sawmill & farm parts that I think that I may need the next year.  I try to pay myself instead of the tax man.  ;D

[Beavertooth]

My old throttle pin compared to the new one. Not hard to see why I wasn't getting full throttle. As I posted earlier I didn't realize it was wearing down and slowing my RPMS down. Did adjust it before I got the new one after I realized it was worn but it wasn't log from being broken into. 

 

  

[alecs]

I'm a mechanical engineer by training.  I wish I could have read a thread like this one when I was in school.  It would have been super helpful to a) get a real world understanding of how things fail in the field and b) get a real world understanding of what makes a design easy to repair and maintain.  In my machine design class, we had to do things like calculate what size bolt would be required for a certain load, but it was all abstract and without any consideration for what parts are readily available or what was required to actually build something and maintain it.  I did show up to school with plenty of hands on experience, and have accumulated plenty more since, but there was for sure a disconnect between the theory in class and practical application.

Side story-
Last summer I was talking to the technician at the Ford dealer who was working on my truck.  I mentioned that I used to be an engineer at Ford and he looked like he was going to kick me out of the shop, or maybe just kick me!  

Thanks for all the helpful info in this thread and elsewhere on this forum.   

[TimW]

Alecs,
My hat is off to you.  In my 42 years as an aircraft mechanic and the last 28 years with Southwest Airlines, I have never heard an engineer state that.  I can't remember how many times I had to drop the blueprints or just tell the engineer,.... .......I'll make it and you can test it and/or draw it.  They just couldn't grasp how it needed to be designed for real world workings. 
I guess nowadays, that doesn't happen with computer aided design with real sized mechanics with 3D motion, drawn into a given space (think under the floors in an airliner and in the avionics bays) to R&R a part or make repairs.
        Again, my hat is off to you.
      

[Old Greenhorn]

Alecs, it takes a lot to admit that. I came up through the shop making stuff starting when I was 14 or so. I always looked at how things were made, went together, and could be repaired as the most important aspects of a design. It took me a lot of years (30) before I earned myself a place doing design work and I felt my responsibility was as much to the folks building and fixing the things I designed as it was to the end user.
 Folks who go through school and right into design work are not taught to think that way and it is getting much worse.
 I was also a 'Ford guy" for many decades until the designs got so bad. Vehicles with both metric and english fittings were the beginning of the end for me. But I bought my wife a ford Taurus at one point and it needed a thermostat. So one night after dinner I pulled it in the shop to do what I thought should be a 15 minutes job (including a beer). I wound up spending more than 4 hours replacing that thermostat after having to pull half the front equipment and part of the top end off the engine to get at the thermosatat. When I finally came in the house and my wife asked if I had got involved in something else, I just said "If I EVER run into a Ford 'Engineer' at a party, I don't care where we are, I am going to punch him right in the F@#$ing mouth, then I am going to whup up on him something fierce". So yeah, I think I know what that tech was thinking. :D
 In the last 10 years of my career as a Manufacturing Engineer I had way too many 'discussions' with design engineers about why and how their designs were overly difficult to make, assemble, and maintain than was reasonable, all of which drove the cost way up. It was a daily occurrence and it wore me out.
 Design work is a lot like writing a hit song. You first come up with the concept (message) you want to Convery, then you write a lot of words and verses, then you edit those verses and pick better words, you write the bridge. Then you edit, edit, edit until you have the message presented in the clearest way with the least words that are chosen exactly to present the message and set the right mood and tone. In design work, that 'editing' is often missed. It is the part of the process where parts are simplified and made so that the tolerances can be opened up, where the total number of parts is reduced and the cost of each individual part is reduced. The part where off the shelf sock parts are put in rather than something made special for 'your design alone'.
 I see little elegance in the designs I come across these days. But it take a lot to impress me. ;D

[TimW]

Well put OGH!  My best design work came when working under STCs (Suppemental Type Certificates) while working under my A&P license.  Only my butt on the line.  No engineer to worry with.  But the draftsman still had to draw it, but after I made it!
Again, my hat is off to Alecs and now to You.

[GAB]

To: alecs, Bindian, & OG;
One day I was looking at a fixture drawing I was working on trying to figure how to mount it to the machine.  Another engineer seeing that I was staring at the drawing on the drafting board asked me what I doing.  I told him I was trying to see if it could be mounted and used in the field.  He replied don't worry about that,let the guys in the field figure it out.  I ignored him.  Fast forward a few weeks and the section manager told me that I designed the fixture, I oredered the tooling to go with it and that I was going to debug it.  Off to Arizona I went to cut 20+" long keyways on 19° 58' surfaces in coal crushers.  The first one took a week of double shifts, the last four took 8 to 12 hours each.  Yes there was a steep learning curve.  After doing the job I found out that some of upper management had said that it could not be done in the field, that the machines would need to be torn down and the parts sent to a machine shop for revision.  Now you tell me.  (As an FYI the shipping wt. of the fixture was one ton.  Also there were some things I never thought of that reared their ugly heads that we had to deal with.)
I spent a lot of time at two other companies later being responsible for building prototypes and doing production support.  I've seen a lot of poor designs that needed a lot of drawing revisions to manufacture a poor quality product.
Many times in Engineering you do what you can with the mess dealt not what you would like or what you know would be best.
GAB
 

[TimW]

GAB,
  We would have worked great together back then!
       

[Stephen1]

30+ years ago I was told by a Small BMW shop repairman I played golf with to buy a BMW off lease. I commented , a little too pricey for me for parts and such. His comment was that parts were more expensive but his labour was less expensive because the car was designed to be repaired so less time changing parts. 

[SawyerTed]

My Dad used to "go over" a new car or new piece of equipment with a handful of wrenches tightening stuff after a few hundred miles.

The LT50 has convinced me my Dad was a pretty smart guy.  Actually, there's lots of other stuff besides.   

After tracing down a "hunting" problem with the Accuset 2 that turned out to be a loose connection and todays issue, I probably should go over it with a handful of wrenches. 

Yesterday, my customer pointed out a small spot on his driveway that appeared to be hydraulic oil under the command control unit.  

Embarrassing and concerning, first that my customer noticed it and second that there was a leak at all on a new mill! 

This afternoon I decided solving the mystery leak was my mission.  I figured leaks almost never get better on their own so it needed relatively quick attention. 

It took a little while to figure out what was leaking in the hydraulic control box.  It turned out a plug with O ring gasket in one valve was loose.  This is the rear toe board circuit.  A 1/16 turn with an Allen wrench stopped the leak.  It took removing 8 screws and 10 bolts to make that 1/16th turn.  

It wasn't a bad leak as far as leaks go.  A half dozen tablespoonfuls at most is all that leaked yesterday.  But, with 18 hours on it, it shouldn't leak. 

The small wrench is just a pointer to indicate the plug that was ever so slightly loose.  Yet it was loose enough to allow a couple of drops of oil by with each cycle of the toe board. 



 

[TimW]

Seems each machine has it's quirks built in.  Mine was built with a wrong drive belt and assembled to the max adjustment on the brake. Wonder what the hiring requirements is for assemblers?

[GAB]

Wonder what the hiring requirements is for assemblers?
hugs,  Brandi

These days - A pulse!
GAB