Using CNC to route edges on a board

[BLM Enterprise]

Has anyone tried to route edges of a board with CNC? I am wanting the edges of my sign to look decorative but do not want to hand route sign. If so, how did you do it? Thank you.

[sharkcutup]

Has anyone tried to route edges of a board with CNC? I am wanting the edges of my sign to look decorative but do not want to hand route sign. If so, how did you do it? Thank you.

I have not done any but I am sure that it can be done on the CNC. I have created several files in V-Carve Pro using roundover bits which previewed well for finishing outside edges of material but have not actually used them. Probably because I have a router table that I can use for the finish details on my projects which also creates less wear a tear on my CNC, not to mention the added router bit changes I would be performing, re-setting Z-axis, etc......

Have a GREAT DAY!!!

Be SAFE around those AWESOME machines!!!

[NewAgent45]

Yes we have done this. We found that form tool type bits work best as shown in the pictures. I have also used tools with the bottom guide bearing removed. You must be sure to limit the depth to less than material thickness.

I added some of these bits to the database. See help for instructions on how to add new "forms".

Hope this helps!

... Rod

[Rando]

I'm with NewAgent45 on this one. One issue can occur when the router bit isn't fully concave, like with a beading bit. You have to be careful if the bit can't be moved out of the cut vertically without cutting in unwanted ways. For example, moulding bits: http://www.rockler.com/power-tool-acces ... outer-bits. If the bit can't be lifted (by the CNC) straight up, then you might need to add to (lengthen) the start and end of the vector it's cutting, so that the tool is actually out of/off the material when the cut starts and ends. That's commonly called a "lead-in" and "lead-out", and can sometimes be a confusing pain to get right, where you have to essentially trick the Vectric/other software into making the lead-ins/outs properly. But, it's just another case where something cool isn't simple or easy.

WRT the cut depth, if the bit you're looking to use has to extend below the bottom of the wood, you can sometimes raise the stock you're using, but it starts to get complicated really quickly, since wood is frequently held down by clamps around the edge. If the bit has to go 'round the entire edge, where will the clamps sit? Which then leads to strange fixtures that require attaching the stock to some type of platform using blind fasteners or through-bolts.

Regards,

Thom [Rando]lph

[NewAgent45]

Rando,

You are right to add that caution and hint on "lead-in and lead-out". I have used this for cutting a slot in the edge with a slotting bit. I always cut some air first to test the program. I second the motion on being tricky. When cutting like this, I always use a starting point at the lower left-hand corner and a project size larger than the actual material size too.

Have a great weekend!

... Rod

[bill z]

We did this by wasting the outer 1/2 inch all round where we clamped the board down. We cut through with tabs.

What we thought of, but have not tried, was to screw some 1/4 inch sacrifice ply to the back of the board where the sacrifice is larger. Then clamp the sacrifice down.

The cut to the edge of the board would not be deep enough to cut through the sacrifice.

I would be interested in knowing how you resolved this.

[NL7U]

I would like to just edge route small plaques. Couldn't I just position the bit at the correct X Y Z coordinates and pretend it's just an upside down router table? I do not have a a big shop and only the one router that is attached to the cnc machine.

[sharkcutup]

Couldn't I just position the bit at the correct X Y Z coordinates and pretend it's just an upside down router table?

Risky and Unsafe, and I would not attempt it!

Have a GREAT DAY!!!

Be SAFE around those AWESOME Machines!!!

Sharkcutup

[cjablonski]

Although I wouldn't recommend using it similar to a router table ( by any means ) if you are referring to using it with a bottom bearing it's feasible. But beyond dangerous, which is 99% of the concern, is that it's also impractical. Consider the interference you may have with the gantry, holding it would be a challenge. Additionally the extra complexity of setting the correct Z height to run it seems like more work than removing the router and remounting it back in the shark. If you have several plaques to do and all have already been cut by the shark, then leaving the router in the shark is already rendered unnecessary. My vote, pull the router. Not at all intending to offend, by any means, but I would consider purchasing a second router. As far as they go, there is a million uses for em, so a second ( or third or forth even) will always get used. Hell, I have 6 em, and none collect dust

[gordread]

I have to add my two cents. Please don't try to use the CNC as an upside down router table for exactly all of the reasons stated here. If this is something you will be doing regularly, grab yourself a second router and a counter top router table, one you can put away when not in use, or if you have a table saw, build one into your table extension, there are lots of more safe options.

Please be safe. I've had too many friends and relatives seriously hurt (ie Lose body parts) because it was faster/cheaper/easier to do it 'this' way.

Gordon