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aostling
07-10-2007, 11:31 PM
I'm fixing to level my 6" Atlas. I have a precision level, but I do not have a supply of shim stock. It's a small lathe, so I wonder if I can use something handy for shim stock -- aluminum foil, perhaps, or photographic film. I could cut up a sardine can with my nifty aviation snips. Any suggestions?

Spin Doctor
07-10-2007, 11:34 PM
If there is a hobby shop near you stop and see if they have styrene card stock. Sold under the Evergreen brand name. Comes in a variety of thicknesses.

http://www.evergreenscalemodels.com/Sheets.htm

Any good hobby shop should also have brass sheet. Stay away from aluminum foil. It will not stand up to use as shim stock.

aostling
07-10-2007, 11:36 PM
If there is a hobby shop near you stop and see if they have styrene card stock. Sold under the Evergreen brand name. Comes in a variety of thicknesses.



Thanks, there is a Michael's nearby. I'll see what they have.

Evan
07-10-2007, 11:52 PM
Aluminum foil is too thin, around .0005 to as thin as .0002". A good source of shim stock is a cheap points/spark plug gauge. Take it apart for a handy selection of thicknesses.

aostling
07-11-2007, 12:46 AM
Aluminum foil is too thin, around .0005 to as thin as .0002". A good source of shim stock is a cheap points/spark plug gauge. Take it apart for a handy selection of thicknesses.

Evan,

Thanks, this is the solution which was staring me in the face. I have just what you suggest, not used on spark plugs in ages.

rotate
07-11-2007, 12:52 AM
Aluminium beer can?

darryl
07-11-2007, 01:09 AM
I found a package of shim stock at the local hobby shop- cheap enough and sizes from .001 to about .015.

pntrbl
07-11-2007, 01:24 AM
Aluminium beer can?

I got some beer can under mine. The cans were .006 and I supplemented that with some brass stock Evan put me onto at the hobby store. The brass came in .002, .003, and .005 flavors. Made by KSF?

SP

BadDog
07-11-2007, 02:45 AM
Technically, what you want is "feeler gages" used for setting valve lash or points. The term "spark plug gage" is generally accepted to mean a wire gage for setting the gap on plugs. :D Get feeler gages for nearly nothing at yard sales or when HF or the like puts them on sale for a $1 each.

On a side point, I bought a whole sheaf (correct term?) of shim stock in a WIDE assorment of sizes and materials from a yard sale. I think I paid $5 for it. Typical size of each sheet is a bit smaller than a piece of paper, and the stack is about 1" thick. There are a selection of examples in Brass, Stainless, and Steel in all sizes from foil-like that you need to be careful with to rather sturdy. Fellow was a home machinist/gun smith and they were selling his estate. Picked up some nice scores that day, also left some dreamer priced items behind, but it always makes me feel a bit sad to go to those, even when I score something nice...

Evan
07-11-2007, 04:19 AM
Technically, what you want is "feeler gages" used for setting valve lash or points.

Hah. Technically it's a leaf gauge. :)

pcarpenter
07-11-2007, 12:29 PM
You can buy longer "feeler gauges" individually from places like Enco. I keep several sizes around handy. I stacked a few thicknesses to figure out how thick the turcite ought to be for a given gib. These longer lengths (10" as I recall) allow for support across the full length of a surface like a gib. I hate shimming at a tiny point and reducing the mounting surface. On top of that, it would produce erroneous results for something like the fit of a gib. These feeler leaves are maybe 30-40 cents a piece as I recall. I do also have a cheap feeler gauge I bought to use for small pieces in a larger variety of thicknesses. Just don't break a good set of shears cutting them. Good ones are hardened and should be cut with a dremel tool etc.

Beyond that, shim stock assortments in various materials can also be ordered from the same places (Enco, KBC, MSC, etc). These are larger sheets of steel, brass, or plastic from which you can trim what you need. For low force stuff with lots of bearing surface, the plastic is fine. I used it to make a temporary shim for the back of a gib. You can trim it with scissors to fit the full back side of a gib, for example, even notching for an adjusting screw so it will move with the gib.

Paul

Fasttrack
07-11-2007, 12:38 PM
Leaf gauge? My machining textbook calls them "thickness gauges" and then says they are commonly called "feeler gauges" since it requires the user to have a good "feel" to get an accurate reading. I always grew up hearing them called feeler gauges. I wonder if leaf gauge is a regional thing? (not that its any less correct if it was)

Swarf&Sparks
07-11-2007, 12:48 PM
Yup, cheap feeler guage sets and brewer's shim :D
Had to shim a precision slide last week, $5 for a 28 leaf feeler guage.
Surprisingly close to spec. I miked em during setup with my trusty old Moore & Wright.
If it's just a case of jack and pack, brewer's shim (beer can) works fine. You can even scrape off the plastic coating to vary thickness.

BadDog
07-11-2007, 02:20 PM
Interesting, never heard it called a "leaf guage". Hmmm...

RPease
07-11-2007, 02:24 PM
Hah. Technically it's a leaf gauge. :)


Hah........."Technically" it's a bunch of thin pieces of steel of various thicknesses (usually progressive) assembled together (or individually) to be used to measure lots of things (i.e. spark plug gap, points gaps, leafs (or is it leaves), or many other things. You could probably use enough of them to measure the height of your favorite beer can.........LOL

Evan
07-11-2007, 04:17 PM
Nope, leaf gauge is the proper term.

example usage:



Spark Plug Maintenance (http://www.02restoration.com/spark-plug-maintenance.htm)


First, what kind of plugs should you use? From 70,000 miles of experience, I like Champions, and contrary to what you may read elsewhere, their cut threads will not damage a BMW if you install them carefully. Champion and other plug manufacturers all put out handbooks on how to inspect used plugs, whether to use a hotter or colder plug, etc., so Iíll skip those discussions here. I use Champion N6Y plugs and my driving doesnít involve a lot of stop-and-go, city-type routes. I clean and re-gap plugs every 5,000 miles and replace them every 10,000. Also, by watching for specials I never pay more than 60 a plug.
Tools needed are:

Spark plug wrench
2 inch ratchet extension
Ratchet handle
Wire feeler gauge or leaf gauge.
A wrench with the rubber insert that holds the plug is best; you can also use the tools from your carís tool kit, which should include the required leaf gauge.

http://www.02restoration.com/spark-plug-maintenance.htm

ERBenoit
07-11-2007, 05:18 PM
Nope, leaf gauge is the proper term.

Not for a single thickness or "feeler" gage.

Assemble a set of individual thickness or feeler gages, then each individual gage becomes a "leaf" of the set.

http://catalog.starrett.com/catalog/catalog/PLH2.asp?NodeNum=22133&Mode=PLIST

http://catalog.starrett.com/catalog/catalog/groups.asp?GroupID=30

ptjw7uk
07-11-2007, 05:29 PM
You used to be able to buy strip gauge material from Vauxhall (GM over the pond) which were hardened and used to set tappet clearances with the engine running on tick over, a very messy operation but you got used to it.
The strips were about 12inches in length not sure if you can still get it as a lot of tappets are now hydraulic.
Peter

Magic9r
07-11-2007, 06:18 PM
My dad calls 'em feeler guages & so do I, & that's 90 years and over 250, 000 miles of motoring experience between us.
Champion are OK but Nippon Denso are good and NGK are brilliant,
and it's definitely feeler guages cos that's what it says in the Snap On catalogue and Moore & Wright of Sheffield, England also use this description,
Pick one unauthoratitive source on the internet as backup & you'll prove black is white and get run over on a zebra crossing :D
Regards,
Nick

Mike W
07-11-2007, 06:27 PM
Small Parts and MSC sell brass and steel shim assortments in good size sheets. Hobby shops usually have smaller brass pieces. That is a lot easier than hacking away on feeler gauges.

Evan
07-11-2007, 08:48 PM
Pick one unauthoratitive source on the internet...

There aren't any authoritative sources for the English language. However, the fact that at least one other person uses the same terminology means I didn't make it up. :)

You can still buy 12" Starrett gauge strip. My local dealer has it. It's what I used for the secondary mount on my telescope. By using .010" hardened strip under very high tension the secondary mirror is mounted as if on a solid plate, absolutely rigid compared to other methods. But, the amount of shadowing of the primary mirror is extremely low, about .4 percent or so of the optical area. Also, by using such thin supports the diffraction spikes are greatly reduced in intensity. The leaves are sandblasted and then cold blued to produce a black matte finish.


Seen from the side:

http://vts.bc.ca/pics/spid2.jpg

But, seen from the axis of the main mirror they disappear. Arrows point to them.

http://vts.bc.ca/pics2/spider2.jpg

Note: This is before I anodized many of the parts flat black. I believe my use of gauge strip in this manner may be original in the astronomy world. I haven't seen it described before where such thin material is used under high tension to give high rigidity as well as low light loss.

HTRN
07-11-2007, 08:54 PM
What about using the steel packing strip?


HTRN

aostling
07-11-2007, 09:23 PM
Note: This is before I anodized many of the parts flat black. I believe my use of gauge strip in this manner may be original in the astronomy world. I haven't seen it described before where such thin material is used under high tension to give high rigidity as well as low light loss.

Evan,

This is a beautiful reflector. I'm wondering if astronomy is why you moved to Williams Lake, where the skies are presumably free of light pollution.

Your radial strips under high tension make me wonder about creep. Do you have to retighten the tension screws occasionally to take up some slack?

But creep is virtually absent in metals, I understand, if the stress is kept below the yield stress, so perhaps you need never fiddle with it.

Fasttrack
07-11-2007, 09:38 PM
There aren't any authoritative sources for the English language. However, the fact that at least one other person uses the same terminology means I didn't make it up. :)


I didn't mean to suggest that you made it up! I just haven't ever seen the term used around here. I've looked in five different machining books, from "Machining Fundamentals" to "Haynes Small Engine Repair" and all of them have thickness or feeler gauges. Makes since that they are leaf gauges if you have a set though.


On a related note, i've always heard that its not a good idea to check spark-plug gap with a feeler - err leaf gauge. Especially if your checking one thats been in the vehicle for a while since a crater can form on the top electrode. The wire gauges are supposedly more precise way of measuring gap.



Oh - HTRN i've used packing strip before for off hand shim stuff. Not sure how uniform it is, i never checked, but for bringing a cutter up to the center of the workpiece or etc it works well.

Evan
07-11-2007, 09:58 PM
Your radial strips under high tension make me wonder about creep. Do you have to retighten the tension screws occasionally to take up some slack?

Not yet. According to Starrett their gauge strip is made from "The finest tempered steel". If we assume that is medium carbon steel, say 1045, then it has a yield strength of about 71 ksi in a spring temper. So, a .010" x .5" strip has a yield strength of about 350 lbs. Since the tension applied on each pair of strips redistributes to all of them the total tension required to cause plastic yield is over one ton. The aluminum ring the tensioners are mounted on also acts as a spring and maintains tension throughout the normal temperature range.

TGTool
07-11-2007, 10:51 PM
Hah. Technically it's a leaf gauge. :)

Hmm, to me a leaf gauge has been more properly called a tapered leaf gauge. They may be tapered in thickness or in width, with markings to show the width or thickness at that point.

For setting spark plugs, the taper is slid in until it jams and the gap is read from the thickness there. For hole checking, the tapered-in-width piece is placed in the hole and the diameter is read where it comes to rest. Somewhere I've got a picture of them, maybe a catalog. I'll look.

Evan
07-11-2007, 11:07 PM
Hmm, to me a leaf gauge has been more properly called a tapered leaf gauge.

Yes, that would be the correct name for a tapered leaf gauge. However, for one that isn't tapered....

aostling
07-11-2007, 11:47 PM
Yes, that would be the correct name for a tapered leaf gauge. However, for one that isn't tapered....

Here's a feeler gauge with 26 leaves. http://www.amazon.com/General-Tools-Leaf-Feeler-Gauge/dp/B000BQRAFG

darryl
07-11-2007, 11:59 PM
I used to use my brain as a leaf gauge, but it was a bit hard on the lungs. Besides, I got too paranoid.

Evan
07-12-2007, 01:15 AM
"Feeler gauge" is a colloquial term for a specific type of leaf gauge. A leaf gauge is any sort of gauge that is made in a flat form to measure thickness. It may refer to a single leaf or a collection of same. There are many types of leaf gauges used in various disciplines including dentistry, machining, auto mechanics and others.

ERBenoit
07-12-2007, 09:55 AM
I used to use my brain as a leaf gauge, but it was a bit hard on the lungs. Besides, I got too paranoid.

Hah! Wonder what this statement reefers, I mean refers to :D

Evan
07-12-2007, 10:47 AM
http://vts.bc.ca/pics2/rm.jpg

Swarf&Sparks
07-12-2007, 11:11 AM
"Feeler gauge" is a colloquial term for a specific type of leaf gauge.

You say tomayto, I say tomahto
Can we get back to machining please?
Lets avoid the pedantry and character assassination.

Evan
07-12-2007, 11:48 AM
No characters being assassinated around here.

Swarf&Sparks
07-12-2007, 11:58 AM
Yeah, sorry Evan, character assassination is on another thread :o

Just like to get the whole thing back on track.
This is a fantastic forum, with many lifetimes worth of experience.