Getting the Z axis Straight

[Ken Sully]

Just repaired my Z axis (rail had a worn spot in it) and replaced the second 2 layers of the spoil board.
I decided to check the spindle and see how it lined up to the spoil board with dial indicator.
First I did the x axis and spun the indicator 90 degrees and was able to get it with in 5/ 1000.
The y axis has been more of a challenge, spinning it 90 degrees I am only able to get it with in 9/1000

I do not see any spec as to what to expect and maybe I am over the top on this one.
If I am would like someone to tell me. Guess I could continue to work on the y axis

[Simops]

Ken,

Hen you did your re-surfacing of the sailboard how was the surface......any ridges thT catches your nail??

I tend to use the fingernail process to gauge how plumb my spindle is. If I can't catch my finger nail at all it's good enough for me.

Cheers

[scottp55]

Ken,
I think you should be able to get a little better than that, and from what I've seen of your work and the detail in it you'd appreciate getting closer.
.009" in what radius?
Not being too picky at ALL
http://forum.vectric.com/viewtopic.p...rammel#p150038

[Ken Sully]

Michael,
I do have some wash boarding, tough to catch a finger nail.

Scott,
Thanks for the link to Vectric, It is .009 using an 8" radius.

So.... guess its back to the Y axis X seems to be fine.

Thanks for your help

[Simops]

Ken,
Originally I had wash boarding along the Y axis (now my X axis as I swapped them) that caught my finger nail distinctly. After some tweaking of the spindle mount fixed that.....still 'see' some wash boarding but no nail catching and very smooth.....I'm happy with that!

Cheers

[gundog]

I was able to put shims in mine to get it within a few thousandths. I made shims from a beer can or pop can. You can buy shim stock in any thickness but the cans are free and readily available and if you are close by I can help you empty a couple beer cans.

[gundog]

In the Y direction I loosened up the bolts on the spindle leaving one bolt slightly tight and used a soft blow hammer to tap the body of the spindle and then sweep back and forth to get it but like you I could not get it as good as in the direction I shimmed but I think I got it to .005" or so. I have a design in my head on a mount that would get it pretty much perfect but never built it before I sold the machine.

[Ken Sully]

Michael,
I think I will need about 24 cans. Being you are going to drink them for me do you have a brand preference?
Thanks for the tip. Going to get a piece of glass and lay it on the top.

[srwtlc]

Hey Ken,

Just a thought here, you could possibly (this is looking at my mounting plate) slightly ream out all but one of the six holes ever so slightly, allowing the plate to be rotated a little more.

[Brady Watson]

The only *easy* angular adjustment you have for the spindle is to tilt the top of the spindle in the -Y or +Y direction using the spindle adapter plate bolts. If you need to make an adjustment in the X direction, some more work is involved...and it isn't for the faint of heart.

Before you do ANYTHING, check the back side of the gantry beam with a framing square of known GOOD quality to make sure adjustment is needed.

The end plates on the gantry have to be loosened as well as the underside beam to plate gussets and the entire beam rotated until it is true. SB uses a special jig to get these right in the factory. However, they sometimes get out of adjustment if they are abused in shipping or mishandled.

In simple terms, it is a 2-step process. The plates have to be loosened + gussets. Adjustments made and checked. End plates snugged down. Doing one side at a time & using a block of wood + 36" clamps, clamp the X car down to the center crossmember to keep that side down. Check for square and work that gusset back into where it needs to be. Tighten it down. Tighten the end plate. Repeat on the other side. Then check your work 6 ways from Sunday - stepping back and adjusting as needed.

Make sure all 4 wheels are contacting the rails all the way down...or you'll have to go back and adjust.

Hope that helps! Been there, done that...more times than I can count!

-B