SS shims
Wayne
Thinnest is .012, largest .015.
One shim has a 10 mm I.D. and 17.5 mm O.D.
The other 15 mm I.D. and 33.5 mm O.D.
I only need a few of each.
Last ones I made where from brass. I sandwiched the
sheet between 2 boards and drilled the center hole.
Then I used snips for the O.D. They were not pretty,
but functional.
I'd like to make some out of SS this time, for more
durability and rust resistance. I haven't worked with SS.
McMaster has type 302 in an assortment pack.
I have no punches and would be too expensive for a couple shims.
Got a mill and lathe.
What's a good way to put the hole in and cut the OD in a
way that would look decent?
Wayne D.
Bob La Londe
news:cLP4n.24561$AO4....@newsfe02.iad...
Epoxy it to a sacrificial block, machine to size and shape, remove from
block with heat.
Winston
> "Wayne" <wayne1...@operamail.com> wrote in message
> news:cLP4n.24561$AO4....@newsfe02.iad...
>> I need to make some donut shaped shims.
> Epoxy it to a sacrificial block, machine to size and shape, remove from
> block with heat.
What Bob said, except use Super-Glue cyanoacrylate.
Epoxy doesn't stick to steel nearly as well.
Start with an aluminum backing plate the same X and Y size
as your shim stock blanks.
Clean and degrease shimstock and backing plate, interleave
layers of copier paper between each piece of shim, all glued
up with Super-glue.
A 4 layer sandwich will give you 4 shims per operation.
Use a thick aluminum sheet to clamp the sandwich to cure
each lamination flat.
HINT! Before gluing, exhale to fog the shim. The condensed
water really speeds up the curing process.
Adjust the direction of mill cutter travel clockwise on
the ID and counterclockwise on the OD so that the ragged
edge appears on the scrap material rather than your top
workpiece.
A propane torch on the backing plate will cause the shims
to release from the backing plate. Use Lots Of Ventilation!
Promptly blow out the flame produced by burning superglue.
They turn out very nicely. Use a random orbit sander to
clean off charring on the back of the top most shim, should
it appear.
--Winston
James Waldby
> I need to make some donut shaped shims. Thinnest is .012, largest .015.
> One shim has a 10 mm I.D. and 17.5 mm O.D. The other 15 mm I.D. and 33.5
> mm O.D. I only need a few of each.
...
> I'd like to make some out of SS this time, for more durability and rust
> resistance. I haven't worked with SS.
>
> McMaster has type 302 in an assortment pack. I have no punches and would
> be too expensive for a couple shims. Got a mill and lathe
...
Besides SS shim stock, McMaster also has SS shim washers, like
at <http://www.mcmaster.com/#stainless-steel-shim-washers/=5f8nkc>,
74 or 72 cents each for .012 or .015 thick, 3/8" ID, 5/8" OD.
I don't see much of a match at McMaster for your other
size, but you could have a look at suppliers of metric shim
washers.
--
jiw
F. George McDuffee
Given the thickness of the material and the few that you need, it
may be possible to chemical or electro-chemical mill these at
home. What sort of accuracy do you need on the ID/OD and is some
slight undercut on the edges OK? Resist, etchant and possibly a
battery charger are all pretty cheap. It may be possible to get
one of the sheet plastic lettering machines [like a plotter but
with a knife to cut the plastic sheet] to produce your "donut"
resists in some sort of stick on plastic. Or if you have a steady
hand just paint the resist on with a fine brush.
see
http://www.cricut.com/default.aspx?AspxAutoDetectCookieSupport=1
http://medicaldesign.com/contract-manufacturing/update_chemical_milling_0309/
http://www.metallographic.com/Etchants/Etchants.htm
http://www.finishing.com/108/82.shtml
Unka George (George McDuffee)
..............................
The past is a foreign country;
they do things differently there.
L. P. Hartley (1895-1972), British author.
The Go-Between, Prologue (1953).
cncmillgil
Since you have a lathe & mill, make a shim die? Seems like just as
much work gluing clamping burning off? Plus you'll have it to make
future replacements if needed?
--
___ ___
/ /\ / /\
/ /__\ / /\/\
/__/ / ------------------------------------ /__/\/\/
\ \ / ------------------------------- \ \/\/
\__\/ \__\/
Gil©
Member of
==American Toolmakers==
using the "old world" ways
with yesterdays technology
building
Tomorrows Dreams
Gunner Asch
Nobody has shim stock anymore??
Gunner
"I am for doing good to the poor, but I differ in opinion of the
means. I think the best way of doing good to the poor, is not
making them easy in poverty, but leading or driving them out of
it. In my youth I travelled much, and I observed in different
countries, that the more public provisions were made for the
poor the less they provided for themselves, and of course became
poorer. And, on the contrary, the less was done for them, the
more they did for themselves, and became richer." -- Benjamin
Franklin, /The Encouragement of Idleness/, 1766
Royston Vasey
Not sure how applicable this link is, I found it interesting:
http://mechanicalphilosopher.blogspot.com/2008_05_01_archive.html
Steve Lusardi
I have a sheet of peelable SS shim stock. It peels in .002" sheets. It comes as a .035" sheet. I make a cutting die on a lathe and
a 60 ton hydraulic press. You would not need 60 tons. I would guess ten tons is fine.
Steve
"Wayne" <wayne1...@operamail.com> wrote in message news:cLP4n.24561$AO4....@newsfe02.iad...
Wayne
Don't need any special accuracy.
I think I'd like to stay away from chemicals though.
Wayne D.
Wayne
> Member of
> ==American Toolmakers==
> using the "old world" ways
> with yesterdays technology
> building
> Tomorrows Dreams
I couldn't see the diagram clearly until I started the reply.
Different font I guess. Usually I use Courier New for text
diagrams since it isn't proportional.
I still wouldn't know how to make a die though, or what
material to use.
Wayne D.
Wayne
Definitely applicable.
I saw them at McMaster, but with SS they were only rated to .010
Can't do custom sizes either.
Wayne D.
Wayne
What kind of cutter are we talking about here? I've mostly
have used end mills, or occasionally a counterbore.
Wayne D.
Wayne
Wayne D.
Wayne
I might as well make my own. That way I'll have shim stock leftover
if needed for something else.
Got the shim stock in today. I just love next day delivery
from McMaster.
Wayne D.
Winston
End mill. I used a 1/8" 4 flute center - cutting type.
Lots of superglue; saturate the paper or coolant will
cause delamination.
Use coolant or the end mill will melt the super
glue and bind in the slot.
Cut SS aggressively to stay under the work - hardened
area.
--Winston