Wood-Mizer Blade Guides getting out of Adjustment

[musikwerke]

I was wondering if any of you folks have had this problem and if so, what you did about it. 

I installed the new High Performance Blade Guides on my 20+ year old LT30.  These are the ones with the bottom 'guide' or wear block / pad.  They came with the glued-on brake lining type pad but I have changed them out to the new all-metal ones. Anyway, my problem is that after a couple of hours of sawing the guides move back away from the blade so that the clearance between the roller flange and the back of the blade is nearly twice what it started out as (by factory adjustment specs).  I know that they have moved and it's not the blade tracking as I scribed a line on the square of the guide shaft and it most definitely moves back.  I have tightened the set screws is tight as seems practical using a regular Allen wrench but they still move.  My thoughts were to make a spacer to fit between the back of the guide and the front of the square mounting tube but after digging through my junk, I came up with a couple of stainless hose clamps that, with a little reshaping, did the same thing.

Now each time I stop sawing and check things out, everything if perfect, blade tracking, guide clearance etc.  I'm just puzzled and can't believe Wood-Mizer would have stuck with this 4-bolt alignment fixture if it didn't work.   

Anyone ever had similar issues?

[Tom]

I don't remember ever having that problem and wouldn't think that the upgraded pads have anything to do with it.   The only backward pressure is what is exerted on the flange of the wheel.

Not having my WM mill anymore, I can't remember for sure, but wasn't the round part of that adjustment shaft sloped or cone shaped?  That would make the backwards pressure try to push a larger diameter rod through the adjustmen/set screws.  If the adjustment/set screws were tight, I don't see how the guide could move backward.

Do I not remember correctly or is the guide now cylindrical rather than cone shaped?

[Bibbyman]

I think you have a problem that you need to take up with Wood-Mizer customer support. 

We field tested the new super guide upgrade for about 6 months before they went into production. There were a few small revision made and I had a pretty steep learning curve to get them adjusted properly.  They are more complex than earlier design with adjustments seven ways from Sunday.  But they've been working great for at least a year now and not moved that I've noticed.

[MartyParsons]

I would check you square hole, I have seen these wear and not hold the alignment, you can also change the allen screws to 3/8  stainless bolts. They should not move.  If you can floop the assembly in the square hole then it is worn. The way to fix this is replace the blade guide arm and weld on a drive side kit we have.
    How many hours do you have on your LT30 ?   If you need the part #s let me know.
Hope this helps.
Marty

[backwoods sawyer]

Is this the style of saw guide that you are using?

When I first installed this on the mill, I had the same problem, but after the screws finally "bit in" it quit moving. The other day I noticed that the guide roller was to far back again. After a close exam, I discovered that the step washer behind the roller was missing. Every time the top sprayer plugs up you have to remove the roller to remove the sprayer to clear it and the washer must have slipped out. I solved the problem by drilling and tapping a hole for the top sprayer on the outside and plugged the hole that was on the inside. You may also note that the bottom sprayer is stainless, you cannot get stainless sprayers from Woodmizer, I get them from a local mill supply store.

The other problem that I have had with this guide is that the screw that holds the metal wear plates in place will not stay tight with out the aid of locktite.

As Bibbyman stated: They are more complex than earlier designs with adjustments seven ways to Sunday. However, once you get them to settle in they seem to be a good guide system.

[musikwerke]

Thanks for all of your replies.
The round portion of the shank on the old guides and the new guides are cylindrical, Tom.  The difference is that the old ones were rusty and over time the set screws had noticably bit into the shanks.  The new ones are of course, shiny new and smooth and I have not tightened the set screws to the point where they have made 'divits' in the shank.

The mill has 2400 hours on it, Marty and the square opening on the guide mount is not worn.  In fact, after painting the mill I had to insert the guides with a mallet because the thickness of the paint made the opening that much undersize.

Backwoods:  Thanks for the info.  I'll keep an eye on the bottom pads.  I know what you mean about the spray nozzles.  I made my own out of 1/8" brass pipe plugs because I use diesel for lube supplied by a hand pump and it only takes a fine mist every so often.  There are a lot of adjustments but once you figure out what they do you can put everything 'right on the money'. 

My hose clamp spacer is doing an excellent job keeping them in place and I can't see why that adjustment will ever need to be changed.  I was just curious if I was the only one who had ever experienced this and I feel better that at least one of you have.
I will say that the new guides do work well.  I only have a 16 HP Briggs and put it right on the governor on amost every cut.  Even when cutting spruce I make consistent cuts with never a blade diving or rising.