Help me understand

[bakerkr]

Hi Everyone -

I just surfaced my table and get the following pattern on the top. I know these pics are small if you need the larger version, just email at bakerkr at cox dot net


9161

[bakerkr]

I'm using a 2 inch cutter setting over 80%.

[bakerkr]

The ridges are slight, I can just feel them when I slide my hand across the table. Can't upload the other two pics, they "exceed" the incredible 50kb limit.

[bakerkr]

9162

[rhfurniture]

Is the shaft of your spindle/router at 90 deg exact to the table? (in both X and Y directions)

[paco]

Whenever I'm confused, I set a straight edge on the spoilboard with a light to see if I just feel the ridges or if the Z is actually out of square.

I do think it's normal to see some pattern and to slightly feel one...

[richards]

Kevin,
As Ralph and Paco have stated, your Z-axis is not perpendicular to the X/Y axes. You'll need to 'true up' your machine before surfacing the spoilboard. I use an inexpensive (less than $100) dial indicator to align the Z-axis within 0.002 of an inch. Others may spend a little more time and get tolerances even tighter, but I'm lazy.

First, make sure that the X-axis and the Y-axis are perpendicular to each other. Don't even start on the Z-axis until the X-axis and the Y-axis are perpendicular.

Next, align one rail of the Z-axis perpendicular to both the Z-axis and the Y-axis. Don't waste your time aligning the body of the router/spindle to the X and Y axes until the rail is first aligned. After the rail is aligned, then align your router/spindle to be parallel to the X and the Y axis of your machine.

Then surface your spoil board.

As Paco said, it is normal to 'see' grid lines in the material. The 'nap' of the spoil board will contribute to the visual effect, just like looking at a football field before the game starts. A good grounds-keeper will use his skills to alternate the direction which he uses to cut the grass to give a visual appeal to the field, when, in effect, the grass is all cut to the same height. So it is with a spoil board. As the cutter moves either CW or CCW, a different visual appearance will occur, but the spoil board will be flat and level.

[Brady Watson]

I'm even lazier than Mike (scary, I know)...I use a 4' level and 1st make sure table is dead level. Then I level off of the T-rail NOT the 2X2 part of the Z axis, the part that goes up and down shaped like a T. I have setup many machines this way, and while you can see lines in the table surface from the MDF 'hairs', you cannot feel them. It is perfectly flat.

"Read" the lines carefully looking to see which way the angles are going. Exaggerate the slope of the cutter in your mind and you'll know which way to tweak the Z axis.

-B

[paco]

Mike,

are you saying that I can tweak my lawn mowing from either conventional or climb cutting?




I actually prefer to cut conventional when the grass is tall and thick!

[richards]

Paco,
When you get to be my age, all lawn mowing is 'climb' cutting.

[dray]

"Paco,
When you get to be my age, all lawn mowing is 'climb' cutting."

That was funny. Ok now im off to a good start today

[brian_h]

Geeeze, I was looking at the top picture thinking, man, his setup almost looks like mine. Then I realized I was wrong. It looks EXACTLY like mine. Finally, I figured out why he re-posted it.

I'm slow, but I eventually arrive!

[bakerkr]

Brian -

Yes, after I did my post I did a search and found your post from a while back. Did you get your setup fixed to prevent this?

Kevin

[jseiler]

Soem have been asking whether your z is exactly 90 degrees. It probably isn't. You can feel a ten thousandth of an inch ridge with your fingernail. Lets presume this is 1 thou. For small angles, you're looking at arctan(.001"/2") (radians) as the angle you are off. In degrees, this works out to less than 30 thousandths of a degrees. For something this small, you might just try torquing the bolts on one side of your z a little harder and see if you can adjust it out with small compressions on one side. Repeated shimming will just drive you nuts.

John

[sawkerf]

I started out using a 1.5 cutter and it wasn't so noticable, but when I switched to my 2" cutter, I could really tell that there was a problem with my Z. It drove me nuts (short trip) 'til I figured out how to make "micro" adjustments to the Z. I made a set of "Turn-buckle style" rigs and mounted them on two sides of my Z axis. Now I can dial it in with relative ease. It also helps stiffen the Z in case I run into something accidentally. Kip

[bakerkr]

Kip -

I had the same ideal.. I was even playing with this ideal just the other day.. can you give me more details / Pics? bakerkr at cox dot com.

Thanks!

[ed_lang]

Sounds like a nice way to adjust. I too am looking for your pictures and ideas.

ed

[pete]

Kip, we must have photos and more details please - sounds like a great solution. Thanks, pete