Underpinning / mitre problems..

[Smiffy]

I'm having dramas with (I believe) my morso cutting my mitres properly.

The blades are secure, the fences are straight (as far as I can see!) and the supports are always in the correct place.

When pinning the joints, there is always a slight gap to the inner edge of the mitre - it's getting right on my nerves as I can't figure out why!

Any ideas people??

[IFGL]

I notice you are in chestefield, who sharpen your blades ? if it is master cut then that is your problem.

[Smiffy]

I bought the morso second hand, with 2 sets of sharpened blades. So to answer your question, no one as of yet! Maybe I could do with investing in a new set...

[IFGL]

if your blades are sharpe, your molding is straight, your rebate supports are set right , and you are cutting just a shave of wood off for your last cut and you are still getting a gap on the inner edge, then you need to pull your left hand fence towards you a fraction.

[Roboframer]

That's correct - and to get it smack on, get the widest flat profile you have and make a small frame, say 8x8" - cut it face down to take the rebate supports out of the equation (or, if you don't want to waste it or don't have anything very wide, use wide battens)

If it's not perfect, move the left fence again, just a fraction, break the frame up and make a smaller one, continue until perfect.

[IFGL]

and repeat, with every blade change

[Smiffy]

On it. Thanks very much! Ill let you's know how I get on / bugger it completely up!

[prospero]

Yep. The the classic left-hand fence tweak. Fine adjustments though....

There should be a scribed line near the fence locking lever and another on the machine bed. This makes eyeballing the angle easier. Or you can lay a length of moulding tight along the fence and move the fence so the other end of the stick deflects about a couple of inches. As the blades get duller, you may need to tweak it a tad more. If you start to get a gap on the outside, you have gone too far.

If you join three corners and there is a tiny gap between the last two faces, That's just about right. Pushing them together will cinch up all the corners nicely. (As long as you do the outer pins first)