Need help shimming head

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seal killer
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Need help shimming head

Post by seal killer »

All--

[ALL IS GOOD NOW. I RECOVERED FROM MY STUPIDITY, as you can read in the following post.]

My mill is nodding off.

I have a Grizzly 3616 (Bill S. caught the error in model number) vertical mill. I can spin the head horizontally and vertically. Except to tram the head to the table in the x-axis, I never do, of course. The table will spin horizontally. I never do that, either. The head will move in the y-axis. I sometimes do that.

What it will not do is allow me to adjust for nod. I need to shim the table.

There are four bolts that hold the base of the table to the knee. They are easy to access. Here's my "plan", critique it please.

After I determine how much correction to apply, I will loosen the bolts significantly. Then I will pry the base of the table up a bit and block it. Next I will insert the proper number of shims.

Questions . . .

How many shims? Do I spread them equidistant between the knee and the base of the table along the front edge?

The Grizzly tech suggested that I use cheapie feeler gauge leaves for shims. Sound good?

Thanks for the help! I need it!

--Bill
Last edited by seal killer on Sat Jan 21, 2023 2:18 pm, edited 2 times in total.
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Bill Shields
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Re: Need help shimming head

Post by Bill Shields »

How much is it out?

Properly shimming is more than just putting a couple of shims here and there.

.maintaining rigidity is also important

A search of the model you described shows me a bandsaw
Too many things going on to bother listing them.
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seal killer
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Re: Need help shimming head

Post by seal killer »

Bill and All--

FALSE ALARM!!!

I made an amateurish mistake. I'll explain . . .

When I moved the machinery to its new home, I took pains to tram the head of the mill to the table. I got it to about 0" in the x axis and less than .001" in the y-axis. So, that made me happy.

The other day, I started work on another little stationary steam engine. When I finished the engine, I started thinking about the simple base, just an aluminum rectangle. I wanted it to have a nice finish, so it needed to be fly cut.

I have a weird fly cutter. It holds the tool bit at 45* or so. It probably would not bother you, but I could never achieve an acceptable finish with it. I decided to make one.

After watching a bunch of YouTube videos about shop-made fly cutters and the cautions concerning tram, I decided to just ensure my tram was still right on the money.

Wow! It was horrible! Good along the x axis, but the y axis dropped beyond the ability of my BestTest to register. Hmmm? What the heck had happened between the last time I trammed the thing and now? I had done no heavy machining. Nothing bumped the mill. I couldn't figure it out.

So I went back to basics. (Don't laugh . . . too much.)

I had both the 6" Kurt and the 10" Phase II on the table. I took them off and set up to indicate again.

First, I marked the entire y distance over which I ever work using the Kurt. That included rolling the head out from its extreme, back y distance to the distance to the front of the table as I moved the table from its extreme y position next to the column, out to its closest position to me.

Hmmm, again. Less than a thousandths . . . about .0007". What was going on? This matched my alignment of months ago when I swept the table with the BestTest.

I stuck the Kurt back on the table and clamped a 6" parallel along the y axis in the vise. (I was thinking the Kurt's table had somehow been hosed.) I cranked the knee up to the BestTest and indicated again. No nod.

Now I am really confused. I sat down and had a Bubly. (Haven't had anything stronger than than that in a very long time; almost 20 years.)

Thinking, thinking, thinking.

Then, as if in a dream, it came to me. Stupid mistake. Something that "back in the day" when I was in the shop daily, I would have never done: I had checked the y axis nod along the top of the moveable Kurt jaw. DUH!

So life is good again.

--Bill
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Bill Shields
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Re: Need help shimming head

Post by Bill Shields »

Not even on a Kurt should you depend on that measurement.

Glad u found it
Too many things going on to bother listing them.
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