Hello all,

For reasons that are beyond my comprehensiong, I loosened the bolts,
scraped out what I could between the column and the base, swept the
table, and added some shims. Actually, I swept the table as a test
before ever messing with the bolts.

First, my Chinese combo wrench was no match for the Chinese lock
washers. Geeeezzzzzz. Hats off to Enco, because their bargain wrench
(23 mm was the charm) held very securely, allowing me to use my bargain
deadblow hammer.

The readings matched what I expected from the face mill: the head was
leaning to the right (almost a shame to fix itg). I was a little
surprised to find about seven thou at 5 inches. At this point, I have
it within a couple thou, and should get more shims before messing around
any more. The alignment should be much improved, and I doubt I have the
material to do better.

So far, I am using all one-thou shims. Would you like me to get some
thicker ones? While I'm at it, are there any cheap but good indicator
holders I should get? I cobbled together a contraption using parts from
the Baker kit and at least one import mag base. Maybe that's good
enough. Most of my dti work is spindle mounted for aligning my vise,
and that is easy (slap it in a collet) and works well.

To tighten the bolts, I gave them a good tug and then a few light whacks
with a mallet. Was that overkill? They were _really_ tight before I
got to them. Do I need to do something else? Having seen a vise slip,
I have renewed respect for milling forces, but obviously, stripping
those bolts would be a BAD idea =:0

Bill

"Bill Schwab" wrote in message
ink.net...

snip----

So far, I am using all one-thou shims. Would you like me to get some
thicker ones?

If you can put a shim in that is the proper thickness and you have one on
hand, it makes screwing around with the job easier because you don't have
to keep chasing the shims to keep them stacked properly. Otherwise, if
you've kept things clean, shouldn't make any difference.

When you shim the base, try to install the exact amount of shim that the
position requires------which is much easier if you have the .001" shims you
mentioned, otherwise it requires a variety of shims---not really necessary.


While I'm at it, are there any cheap but good indicator
holders I should get? I cobbled together a contraption using parts from
the Baker kit and at least one import mag base. Maybe that's good
enough. Most of my dti work is spindle mounted for aligning my vise,
and that is easy (slap it in a collet) and works well.

I've always used the attachments that came with my indicators, but when I
need something beyond normal application I use the large unit that came with
my Starrett mag base. By chucking a short piece of 3/8" diameter material
I can then use pretty much any kind of extension needed. I'm not sure
what the new ones look like, but mine has a large knurled nut that unlocks
the swivel that accommodates two 3/8" rods---which you can then place at any
angle you prefer. Hope this makes sense. It does when you're holding the
attachment. Beyond that, I have no suggestions.

To tighten the bolts, I gave them a good tug and then a few light whacks
with a mallet. Was that overkill? They were _really_ tight before I
got to them. Do I need to do something else? Having seen a vise slip,
I have renewed respect for milling forces, but obviously, stripping
those bolts would be a BAD idea =:0

Agreed, stripping them would be a bad thing, but it might be a good idea to
check proper torque specs for the diameter bolt in question and use a torque
wrench. Breaking the bolt wouldn't be nearly as bad a deal as having the
head move under a cut. If you do use a torque wrench, unless you can
ascertain that the bolts are heat treated, tighten them to specs for a class
2 bolt. That's playing it safe. I'm not sure how I feel about using a
hammer on the threads. I've always just trusted my instincts when
tightening bolts, but then I've tightened one hell of a lot of them.

Harold

Harold,

When you shim the base, try to install the exact amount of shim that the
position requires------which is much easier if you have the .001" shims you
mentioned, otherwise it requires a variety of shims---not really necessary.

I'm close as it is, so I will probably stick with one thou.


While I'm at it, are there any cheap but good indicator
holders I should get? I cobbled together a contraption using parts from
the Baker kit and at least one import mag base. Maybe that's good
enough. Most of my dti work is spindle mounted for aligning my vise,
and that is easy (slap it in a collet) and works well.


I've always used the attachments that came with my indicators, but when I
need something beyond normal application I use the large unit that came with
my Starrett mag base. By chucking a short piece of 3/8" diameter material
I can then use pretty much any kind of extension needed. I'm not sure
what the new ones look like, but mine has a large knurled nut that unlocks
the swivel that accommodates two 3/8" rods---which you can then place at any
angle you prefer. Hope this makes sense. It does when you're holding the
attachment. Beyond that, I have no suggestions.

That helps. I will find the isolated pieces that I need to make a
dedicated rig; it should be a lot cheaper than the complete sets and
will prevent lost parts and time.


To tighten the bolts, I gave them a good tug and then a few light whacks
with a mallet. Was that overkill? They were _really_ tight before I
got to them. Do I need to do something else? Having seen a vise slip,
I have renewed respect for milling forces, but obviously, stripping
those bolts would be a BAD idea =:0


Agreed, stripping them would be a bad thing, but it might be a good idea to
check proper torque specs for the diameter bolt in question and use a torque
wrench. Breaking the bolt wouldn't be nearly as bad a deal as having the
head move under a cut. If you do use a torque wrench, unless you can
ascertain that the bolts are heat treated, tighten them to specs for a class
2 bolt. That's playing it safe. I'm not sure how I feel about using a
hammer on the threads. I've always just trusted my instincts when
tightening bolts, but then I've tightened one hell of a lot of them.

"Hammer on threads" makes it sound worse than it was: I used a soft dead
blow hammer on the end of medium length wrench. It took a lot more of a
whack to get them loose than I used to tighten them; each of them took
three light taps with progressively less motion each time. I will check
on class 2 bolts; that sounds a lot nicer than winging it. Somehow, I
suspect I will need a bigger torque wrench than the one I have on hand
for small engines[*].
[*] Don't get the idea that I know what I'm doing; I'm simply too lazy
to cart a mower off for service

Thanks!!

Bill

"Bill Schwab" wrote in message
ink.net...
snip-
I will check
on class 2 bolts; that sounds a lot nicer than winging it. Somehow, I
suspect I will need a bigger torque wrench than the one I have on hand
for small engines[*].

Damn, late last night I was thinking about my response and wondered if I
said. I meant to say *grade* 2. Class is a reference to the thread
itself, not the strength of the bolt (which will automatically have a class
2 thread).

The reason I suggested grade 2 bolts is because of the unknown with the
existing bolts. They may not be heat treated. The torque specs for a
grade 2 would be lower than for a grade 5 or grade 8 bolt. If the thread
depth in the casting is double the diameter, if you buy new ones, shoot for
stronger bolts. Grade 2 is the lowest, just plain low carbon steel.

The only problem I had with the soft blow hammer is that it's hard to know
how much you're putting on the thread, but if you have a sense of how much
is too much, go with it. Didn't mean to imply it was wrong, or a bad way
to go, it's just that torque wrenches remove the unknown.

Harold

Harold,

Damn, late last night I was thinking about my response and wondered if I
said. I meant to say *grade* 2. Class is a reference to the thread
itself, not the strength of the bolt (which will automatically have a class
2 thread).

No sweat; I'm actually happy it's a concept with which I was already
familiar.


The reason I suggested grade 2 bolts is because of the unknown with the
existing bolts. They may not be heat treated. The torque specs for a
grade 2 would be lower than for a grade 5 or grade 8 bolt. If the thread
depth in the casting is double the diameter, if you buy new ones, shoot for
stronger bolts. Grade 2 is the lowest, just plain low carbon steel.

That's a good way to look at it. Beats an educated guess with a hammer


The only problem I had with the soft blow hammer is that it's hard to know
how much you're putting on the thread, but if you have a sense of how much
is too much, go with it. Didn't mean to imply it was wrong, or a bad way
to go, it's just that torque wrenches remove the unknown.

I appreciate the feedback. Given how hard it was to get the bolts
loose, I had to do something beyond pull on that wrench, and I didn't
have a workable extension. I did some milling yesterday (including some
deep cuts in Al), and some flycutting today; no disasters yet =:0

With the flycutter, I can already see a massive improvement in the
alignment. Suddenly, the "leading and trailing edges" both typically
leave marks on the surface. I won't claim that it's dead nuts yet
(pretty sure it's not), but it is probably not off by much.

Bill

"Bill Schwab" wrote in message
...
snip-----

With the flycutter, I can already see a massive improvement in the
alignment. Suddenly, the "leading and trailing edges" both typically
leave marks on the surface. I won't claim that it's dead nuts yet
(pretty sure it's not), but it is probably not off by much.

Bill

Cool! That's what you're looking for.

My experience with mills indicates that you'll never get it "perfect".
There's rise and fall to some degree in almost all tables, so you get a
changing pattern, but on the average, you don't want a lip where cuts
overlap. It will always show a difference because of the variable feed
rate, almost non-existent at the edges of the cutter, and the coarsest @ 90
degrees. I think you get my drift. Bottom line is when the head is
correct, you don't get steps. That's the target, anyway. The cross-hatch
you mentioned as an excellent indicator that the head is correct in one
plain. When you can duplicate that pattern by moving the saddle, the head
has to be true.

Sounds like you're getting a handle on the machining thing, Bill.

Harold

On Thu, 2 Feb 2006 17:37:07 -0800, "Harold and Susan Vordos"
wrote:

Agreed, stripping them would be a bad thing, but it might be a good idea to
check proper torque specs for the diameter bolt in question and use a torque
wrench. Breaking the bolt wouldn't be nearly as bad a deal as having the
head move under a cut. If you do use a torque wrench, unless you can
ascertain that the bolts are heat treated, tighten them to specs for a class
2 bolt. That's playing it safe. I'm not sure how I feel about using a
hammer on the threads. I've always just trusted my instincts when
tightening bolts, but then I've tightened one hell of a lot of them.

Harold

Breaking a few bolts and stripping a few threads with misc
wrenches and sockets is a priceless learning experience. The
more difficult it is to fix/replace said broken item the
faster one seems to learn (at least for some of us, there
are those that never seem to figure it out).

A man has to know his limitations and strength.

Here's a few torque charts I found, just in case you didn't
dig one up yet:

http://dodgeram.org/tech/specs/bolts/SAE_bolts.html

http://www.hastingsmfg.com/Service%20Tips/torque.htm

or if previous link with the embedded space doesn't work:

http://makeashorterlink.com/?X3F21359C

and a metric chart:

http://www.boltdepot.com/fastener-in...ded-Torque.htm


--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

Leon,

Breaking a few bolts and stripping a few threads with misc
wrenches and sockets is a priceless learning experience. The
more difficult it is to fix/replace said broken item the
faster one seems to learn (at least for some of us, there
are those that never seem to figure it out).

True enough, but let's _not_ try it on my milling machine, ok


A man has to know his limitations

numerous and indefinite

and strength.

few and defined



Here's a few torque charts I found, just in case you didn't
dig one up yet:

Thanks!!!

Bill