Wadkin Bursgreen 10" not cutting square

[Pedro_Hernandez]

Good Afternoon

I'm having problems getting a square cut on our Wadkin Bursgreen 10" AGS tilting arbour saw at School.

I'm baffled as the saw blade is square to the table and the mitre slide is also square to the blade and the fence, which is also square to the table .The saw blade is also running true and I stripped the saw down yesterday and cleared all dust/resin and residue from the rise and fall/tilting mechanisms.

However I'm still getting a back cut , in effect over a cross cut using 150mm pine it's about 0.8 -1mm out !. Any help would be much appreciated.

Peter

 

[Steve Maskery]

It sounds as if you have alignment problems somewhere. Have you checked that the blade is parallel to the mitre slot?
S

 

[jo-53]

I had a similar problem some time ago with a startrite 275, and couldn't see what was causing it, as I remember ( it was over 10 years ago) I think it was "run out" caused by the blade running slightly out of alignment on the spindle.I remember I bought a new blade to make sure it wasn't the blade itself, but never really solved the problem.
I hope you sort it out, and I'd be interested to know how.
Best of luck
Jo

 

[Pedro_Hernandez]

Hi

Yeah the blade is parallel to the mitre slot, I followed the instruction in the original manual to check this.

We use TCT blades and thier all square and no tips missing yet the same problem occurs regardles of which blade I try. It would be nice if all I needed was a new blade for a quick fix Jo, however thing's are never that simple !. Unless ofcourse all my blades are dull !.

This is a very old well used School machine so one might suspect worn bearing's/arbour. The only other thing I could attribute it to would be the mitre slide, looks like it's had some work on it to ensure a good fit, unless the centre punch marks all along one side of the slide are normal ofcourse !.

Peter

 

[Digit]

Riving knife?

Roy.

 

[Pedro_Hernandez]

Riving knife?

Roy.

I've already elimated that from the equation Roy, with or without the riving knife the problem still persists.

However the arm that the riving knife bolts to has movement up and down on the spindle, is this normal ?.

Peter

 

[Digit]

In my experience, yes!

Regardless of your tests, if the blade is cutting on the up stroke, ie, the back of the blade, then the wood is either closing up on the kerf or it is not tracking parallel to the blade or the spindle is bent.
I test for parallel to the slot using a digital vernier, checking at the front and the rear then also rotating the blade and rechecking.
A bent spindle will act like a wobble blade.

Roy.

 

[Pedro_Hernandez]

Cheers Roy, I use a dial gauge and non digital vernier, with the same process you noted above. There's no wobble on the blade and the blade is parallel.

I'm starting to suspect my mitre gauge is the culprit, It look's like it's already been tuned in it's lifetime and on reflection it's not the tightest of fits in it's slot. It's possible that any play would be componded when the blades starts to cut, pulling in the tiimber towards it and to the right.

I'll tune the mitre gauge up after half term, it not been done since my time at the School (two years) so let's hope it something as simple as that !.

Thanks again.

Peter

 

[Digit]

The bar on mine was sloppy so I fitted three brass plugs into the side with a grub screw to ease each of them forward.
The angle of the blade to the slot has no effect on the angle of cut! The only exception to that is if the blade is dished or so far out of parallel to the slot that the angle/dish is greater than the kerf, when the blade rubs and pushes the wood sideways.

Roy.

 

[lanemaux]

It comes to my mind that the culprit may be more subtle than an alignment issue. If the saw is as well used and possibly abused as is the case with many saws in a school enviroment are wont to be, might not there be some minor play in the arbour? Nothing immediately obvious , just something evident under the stress of use? Not familiar with your saw , but it strikes me that wear on the undersaw attachment points for the arbour on any tablesaw might cause the symptoms described and yet not show when the saw was not in use. Just a thought.

 

[Digit]

Yep! Which is why I mentioned the wobble saw effect. If Peter starts with an accurate mitre fence all of these issues can be resolved one by one.
If set up with a mitre fence at 90 degrees to the bar results in someting other than 90 degrees, then the fault must lie with the blade set up.

Roy.

 

[9fingers]

The table slot must be parallel to the blade when under load. Any error in this cannot be corrected by the mitre gauge.
Just setting the mitre gauge at 90 to the blade does not ensure a 90 degree cut.

You can tune the slot alignment by ear as thee should be just the slightest rub of the teeth on the rear of the blade after the main cut has been made by the front teeth.

Bob

 

[Digit]

You can tune the slot alignment by ear

Or the amount of wood dust in you teeth! :lol:

Roy.

 

[Pedro_Hernandez]

Thank you all for your advice, youve all been very generouse with your help for a newbie on the forum!.

I stopped on till gone 6-30 at School on Friday and I'm pretty sure I established that the mitre slot was parallel to the blade and there was no warp to the blade fitted or evidence of wobble down to worn bearing's. I got parallel sides when ripping on the fence so I'm putting my bets on the cross mitre bar being having to much play.

I remember looking at it last thing before the Caretaker kicked me out and there was play in it, with atleast 0.5 tp 0.7mm side to side.

I'll let you know how I get on after half term.

Thanks again.

Peter

 

[misterfish]

The bar on mine was sloppy so I fitted three brass plugs into the side with a grub screw to ease each of them forward.

With the amount of play you have found this would be the best option. My saw has a 20mm mitre slot and 'standard' 3/4 inch bars are way too sloppy. I have a Kreg mitre that has this as a standard adjustment. I also have a smaller width gauge that I can use on my router table which has a 'standard' slot. To use this on the TS as well I drilled and tapped three holes across the bar and use nylon grub screws.

Misterfish

 

[davem62]

Hi, i have the same ts and the mitre gauge from rutlands is a very good fit ,as the bar has four tiny ball bearings fitted into one side of the bar with springs behind and are tensioned from the other side with grub screws,making it possible to remove all play, and adjustable to be as tight or free to slide as you wish,hth david