Bridge Saw Breaking last 10mm ish on Porcelain

[TheNamek]

I've got a Rubi DU200LBL. When I cut hard porcelain almost always 'breaks' when I reach the last 10 to 15mm. I'd upload a pic if I can figure how on a mobile. I have both continous porcelain and turbo blades from ATS - makes no difference what blade, speed of cut.

I reckon it might be down to vibration. I usually clamp the workpiece to the bed but can only do so on one side. If I don't clamp then the quality of the cut edge is rubbish (chips galore). Any ideas or experience?

 

[White Room]

Don't own one but do a cut from the other end of of the tile about 20mm to alleviate the chipping.

 

[Concrete guy]

Check that the blade is running true.

It shouldn't be necessary to clamp the tile down. There's something putting stress on the blade as it cuts that's causing the last bit of the tile to break. That could be:-

Non level bed, head running not square on the bridge, bearings worn on the motor allowing the axle to wobble slightly or even the axle itself slightly bent.

If it's displaying the same symptoms when the blade is changed then it's unlikely to be the blade.

Do you have a third blade for the machine so you can completely discount that being the issue?

 

[TheNamek]

Thanks for reply. Machine was only new couple months ago. I don't have a third blade capable of cutting porcelain but I strongly suspect it's not a blade problem.

When you say the bed not being level, surely it doesn't matter given that the bridge can tilt upto 45 degrees anyway.

However, it's interesting that you reckon it's not necessary to clamp down the workpiece. I have found that the quality of the cut edge is significantly better when the piece is clamped. This is because vibration is controlled. Whether the vibration is a symptom of a bent axle or blade running untrue ia not something I know how to determine. It looks like I'll have to do some homework!

 

[Concrete guy]

It shouldn't be vibrating, it should be a reasonably smooth operation so that's somewhere to start.

 

[Rookery]

I'd be using a dry rail cutter. Much quicker.