Run Past Dado Grooves

[J Flowers]

Good Day all.

In setting up grooves for Blind Dado's, I need to extend the groove at the ends.  This is usually only on a "x" or "y" axis and approximate half the thickness of the tool being used.  Is there a way that I am not finding to do this?  a "trick" of sorts, or a feature I am not finding.  Currently using 2018.

Thanks for the help.........

 

Jeff  

[Colin Gilchrist]

It really depends on how you are driving the toolpaths.

If you are using Contour, there is a 'Extend/Shorten' option on the Lead In/Out page.

I would set the option to Extend by 51% of the cutter diameter. But also 'disable' the other 'line / arc' entry/exit options.

When you look at the Data Entry Fields, the 1st field's is '% of tool dia', and the 2nd field is 'actual length value'. (Adjusting either one, updates the other.)

[J Flowers]

Thanks Colin for the info. I have played with the contour function in this way some. I have however, found that it is usually more useful for me to use pockets to run my grooves. 

Any suggestions using a pocket?

[crazy^millman]

1 hour ago, J Flowers said:

Thanks Colin for the info. I have played with the contour function in this way some. I have however, found that it is usually more useful for me to use pockets to run my grooves. 

Any suggestions using a pocket?

Using Pocket not really you would have to draw the pocket to have the bump outs like you are describing. Might find it best to do a pocket to get the square shape and then come back with a contour to do the bump outs like you saying to allow for the width of the dado to work like you want. When I made custom windows and doors over 30 years ago we did all of this by hand. I can only imagine what I could do with a router today. We made Arch Windows and everything bay hand with templates and jigs. We made a custom arch press for the laminating forms we glued together. Was made from 2" x 2" x 1/4" Square tubing for the frame. All the glue up jigs were wood, but the clamp straps were 1-1/4" ACME rods with a Hand made handle welded on the ends to tighten the straps down. The other ends were attached to a 16 Ga piece of sheet metal that wrapped around the thin Veneers we glued together to make each frame.

[Colin Gilchrist]

2 hours ago, J Flowers said:

Thanks Colin for the info. I have played with the contour function in this way some. I have however, found that it is usually more useful for me to use pockets to run my grooves. 

Any suggestions using a pocket?

For Pocket, I'm assuming your slot geometry is a chain (closed loop), correct?

The easiest way to extend this geometry is with the Transform > Stretch command.

With Stretch, you use a "click and drag window" to select the geometry. If the geometry is completely inside the window, it will "move". If the geometry intersects with the window, then that geometry with "stretch".

On the slot example, you get to 'move' the end of the slot, while maintaining the 'tangency' of the endpoints of the chain.

If you had 10 slot chains for example, 1.0 wide, but 15.0 long, and you wanted to extend both ends of the slot by .500, you could use Transform > Stretch, window the bottoms of all the slots (window intersects all 15" long lines, while all the 1" lines on the bottom are fully inside the window). In the dialog, select 'move' and Y-.500. That 'stretches' the bottoms of all the slots. Now repeat the process on the top, and use Y+.500. Two quick operations, and you're ready to cut.

Stretch also works on chains with existing toolpaths. Just stretch the geometry and regenerate...

[J Flowers]

Thanks Again Guys.

In the Past and Currently, I am drawing a 2 d geometry over top of any "grooves" that I absolutely need to.  I should clear up the thought process a bit.

I am importing Solid bodies from designs of others doing.  The solids have the "grooves" with in them that I need to cut.  I use the bottom face of the groove for the geometry that I want too cut.  It is natural that the tool will not run past the end of that face.  Therefore it leaves the rounded corner matching the tool in every corner of that face.  You can change the size of the groove in the x, y by changing the "Stock to Leave on Walls".  but it does it in both the x and y.  would be good if I could leave/remove stock only in the y or the x.    

 

Thanks Much for the Ideas.

 

Jeff Flowers

Louisville Lumber and Millwork

[Steelab]

On 7/11/2018 at 12:56 PM, J Flowers said:

Thanks Again Guys.

In the Past and Currently, I am drawing a 2 d geometry over top of any "grooves" that I absolutely need to.  I should clear up the thought process a bit.

I am importing Solid bodies from designs of others doing.  The solids have the "grooves" with in them that I need to cut.  I use the bottom face of the groove for the geometry that I want too cut.  It is natural that the tool will not run past the end of that face.  Therefore it leaves the rounded corner matching the tool in every corner of that face.  You can change the size of the groove in the x, y by changing the "Stock to Leave on Walls".  but it does it in both the x and y.  would be good if I could leave/remove stock only in the y or the x.    

 

 

I run into this issue also and use a few ways to get around it.

1- if your cutter is the dado width create a line from the mid point of the dado ends, split the line in the middle and run 2(ramped 2d contour) cuts, with cutter comp off, from the center to each end. This will stop your tools center at the end of the dado.

2- In the model prep tab use Move to change each end of the blind dado by about 51% of the cutter diameter. Then instead of creating 2d geometry just use the Solid loop selection when picking your toolpath geometry.

3- To maintain the width and length of the dado, use the create curves on all edges of the bottom face of the dado and then create a "Relief" Fillet(using the radius of the tool) in each of the 4 corners so you end up with a dog bone shape. Of course using this method you end up with a little cutout next to the piece going into the dado, but it's very useful when you can get away with it so you don't need to go back in with a re-machining toolpath and a tiny cutter...