Router placement.

[GullyFoyle]

BillK

Would there be any advantage to balancing the router equalizing the weight of both sides?

Milling aluminum, router looks to be near even with the mount
https://www.youtube.com/watch?v=15n0CHhcJts

Router looks to be midway
https://www.youtube.com/watch?v=zatLtKozhcE

Maybe there exist design advantages to the various positions.
We need an Engineer and some modeling software for a workup on the pros and cons of placement. I bet it varies with choice of router too, different weights and balances.
Makes me wonder about the metal cutting, better cut close to the clamp?
Thank You for the observations.

[BillK]

Would there be any advantage to balancing the router equalizing the weight of both sides?

I often thought about this and always come down on the side of no, not really. While it would lower the angular flex between the upper and lower X rails, the added weight will increase Z flex in those rails.

As far as metal cutting closer to the clamp: depends with proper feed speed adjustment you can achieve similar results regardless of position. Closer to the clamp maybe more stiffer and allow for a higher speed but could cause X axis issues I mentioned above.

The analysis can be done without too much software firepower. The flex results are in thousandths of an inch and depending on what you are doing if that makes a difference or not.

[GullyFoyle]

I can't remember if it was that video or a post regarding milling steel but the person milling said they went very slow.
Thanks again.

[sk8nmike]

2 things to keep in mind with the placement of the router in the clamp. First weight is irrelevant since the clamp will be supporting the entire weight of the router no matter where it's clamped. Second leverage, try holding a pencil near the eraser and try writing. Much more control if you hold it near the tip. You can add in centrifugal force too if you want, the closer to the middle of the spinning armature you get the easier it is to tilt the router.

[GullyFoyle]

A better analogy would be a pencil with a five pound spinning motor on the end.
You need to hold that in the middle.
Well, where the forces balance.

[GullyFoyle]

I installed using the bottom three holes on the gantry. My router sits high when z bottoms out.
No big deal I'll add a sacrifice board raising it to the correct height.
On the positive side I'll never cut the bottom.

[tonydude]

Top three holes is the normal unless your carving thick material. I never needed to raise my gantry even when I use 1 1/2" to 2" material.

Tony

[Wolffie1]

Why is it a bad idea to have the router all the way down? Too much pressure on the clamp? Wouldn't the weight of the motor add to the stability when it's down that low?
Oddly enough it's the updated manual.

The further you push the router down, the more Z Axis you lose.
Cheers
Wolffie

[GullyFoyle]

Top three holes is the normal unless your carving thick material. I never needed to raise my gantry even when I use 1 1/2" to 2" material.

Tony

Pictures nor the videos on the internet and quote from the manual.
Just like router placement there seems to be a lot of room for interpretation.
It would have been nice to find it all standardized.

http://www.rockler.com/images/logon/201 ... 2hd3-2.jpg

http://www.youtube.com/watch?feature=pl ... Y_CD3vIB5c

http://www.youtube.com/watch?feature=pl ... x-oXgfSwRU

Line up the six pre-drilled bolt holes in each of the two gantry mounting brackets and
insert, but do not fasten, the 12 bolts through the gantry assembly and gantry mounting
bracket. You may find it easier to have an assistant to help during this phase of
assembly. You should use the top 6 holes (3 on each ‘side’ of the individual arm) in the
gantry arm where more than 6 holes are pre-drilled in the gantry arm.

[GullyFoyle]

Why is it a bad idea to have the router all the way down? Too much pressure on the clamp? Wouldn't the weight of the motor add to the stability when it's down that low?
Oddly enough it's the updated manual.

The further you push the router down, the more Z Axis you lose.
Cheers
Wolffie

The dust boots are designed for the tip of bit at edge of brush. Too high and it is harder for z to travel, too low and the bit is beyond the boot not collecting properly.
The dust boot depth makes for router placement, if you use a dust boot.