Tramming Spindle

[Leo]

What is your best strategy to tram (make perpendicular) the spindle to the table?

I am not happy with my strategy.

[IslaWW]

Leo...
With your experience I feel like Im preaching to the choir.
First method:
Surface an area a foot square (raster)
Use a 1) bent Z rod or 2) tram gauge with indicator on smooth blocks at the opposite side of swing, adjust

Second method:
Use a purchased dual indicator tram gauge.
surface with 1 1/4" bit a circular area (on vector spiral ramp) the diameter of the centerline distance of the indicators
calibrate and adjust

The reality is that in the majority of cases, any method gets you close. With router tables I have often had to chuck up a 2.5" surfacer and make multiple trial and error surfacing passes to get rid of the ridges. On my mill, pretty close to set and forget.

[ozymax]

I get my spindle as close as I can by using an engineers square resting on the table with the blade along the body of the spindle.
Then I skim the table surface with my largest diameter cutter (19mm) and take note of the marks that the cutter makes.
Then I mount a Z shaped bar in the collet chuck. My home made bar is made from ground shafting and is 6mm diameter for rigidity. When it swings, it gives me approx 300mm arc. The bigger the arc the better, but you loose rigidity in the Z bar if you go to big.
I then lower my spindle so that it is just clear of the table and I can swing the Z bar 360° and not touch the table surface.
I then use mechanics feeler gauges between the tip of the Z bar and the table at 90° intervals around the spindle centerline. The feeler gauges span the cutter marks that the first skim cut left.
I note those measuremnts down and adjust the spindle tilt till all feeler gauge measurements are equal.
When I'm happy with all measurements, I re-skim my table and compare the cutter marks.
It's worked every time for me.
I had to surface a work piece today and you'd swear that it had been through a planer it was that good.

[Leo]

Gary,

It is sometimes a little embarrassing to admit that one is not good at something. I believe that nobody is good at everything and there is always room to get better at what one is not good at.

I have never used the dual indicator system. I am wondering if I could make one.

[AndyPitts]

I cannot add to these good suggestions, but after tramming as good as I can I can still see telltale cutter marks, visible but with infitesimal depth. Now I wonder if it's just the nature of a cutter to leave some small stepping as it rasters.

[Rcnewcomb]

Andy,

Fishtail router bits tend to leave swirls.

An end mill with a radiused edge will not do that.

[highpockets]

I level a 16" square 1/8" tempered glass plate to the top of the table using a dial indicator in the spindle. I've seen people using playing cards or scraps of paper to shim up the glass plate. I decided to make a glass plate with bolts in each corner that I can use to fine tone the level of each corner.

I then use a tram that I made out of a 5/8" thick aluminum bar with dial indicators to tram the router head.

The side advantage is I had fun making the tools to do it with

[IslaWW]

Leo....

"It is sometimes a little embarrassing to admit that one is not good at something. I believe that nobody is good at everything and there is always room to get better at what one is not good at."

Amen to that!
I don't think there is an accuracy advantage to the dual indicators, but they will read a few seconds quicker when making adjustments due to not having to rotate.

[martin54]

Leo I don't doubt that you would be able to make one with your background but the challenge will be achieving the right sort of accuracy with twin gauges. As Gary has said there probably isn't an accuracy advantage with twin gauges & a single gauge version is easy to make. Gary has loads of money so can afford all the fancy toys
I made a single gauge version which works well, only problem I find with a largish table is that it can be difficult to read as you rotate it, you have to follow it round the table your table is larger than mine so you will need really good eyesight or be able to jump up on the table

[Leo]

I looked at the Edge Technologies web site. The dual tramming fixture is $99. Not bad.

I read the manual and it is pretty straight forward.
Calibrates just as I would expect.

I have a decent collection of Federal Products .0001 indicators.
I work there and just got some rejects, they don't calibrate well enough to put in stock, but they still work just fine for a hobby shop.

I have some aluminum on hand.
With a nice CNC machine and nice Vectric programming software, so,,,, heck yeah,,,, I can make that.
Gotta be fancy. I can get it color anodized too.

Bucket list item - in the NEAR future.

I do thank you for the input

[IslaWW]

Leo...
While you are at it, can you make a couple magnets that sick to MDF spoilboard for calibration?

[Leo]

Two rare earth magnets with double sided tape - on the way

[IslaWW]

I walked right into that one