Shim Stock Questions

[ShopShoe]

I have been using inexpensive feeler guages, old printing plates (all 0.005-in.), and a few pieces of brass shim I was given. I am thinking about buying an assortment of real shim stock. My preference is brass, but steel is cheaper. The 6 x 12 in assortment will last longer than I will.

1. Does someone sell an assortment of thicknesses where the sizes of sheet are maybe smaller, say 4 x 6 in.? Obviously, the price would need to be correspondingly lower.

2. What is the best way to cut small pieces? I already have standard size snips of various types that I used to use for auto-body sheetmetal. These don't work well with thin metal. This probably affects the choice of brass or steel.

3. A punch would be nice, but I don't think I'll use one enough to justify a good one: would the knock-off of the Roper-Whitney punch be useful, or just a waste of money? I can drill holes after sandwiching thin metal between wood or plastic, but sometimes the hole is rough or everything shifts.

--ShopShoe

 

[MachineTom]

It depends on what you are using it for, as to the material. I cut real thin with sissors, thicker with snip's regular and avation type. The brass bends easier, I buy that in roll form .010" 6 x 60". For steel the 6 x 12 seems right for most uses, and a selection of 1/2 x 12 strips, mostly thin.

Rolls are available in different widths, but much longer lenghts.

 

[ShopShoe]

Thank you MachineTom

 

[GailInNM]

I have a small Diacro bench shear, but in years past I used a swing arm paper cutter to rough cut BRASS shim stock up to about 0.012. Like Tom, I use use sissors for thin stock. Kitchen shears that have a very fine serrated edge work quite well and for smaller cuts I have a pair of surgical sissors that only have 1-1/2 long blades. Good for stuff up to about 0.006.

For punching holes in thin stock there is an old trick that I use quite often. Put a piece of mild steel on parallels in the mill vice and drill a hole the desired size in it. Then grind the smooth drive end of the drill square and chuck it up. Set the quill stop so the now sharpened end just goes into the mild steel hole about 0.015 inch. Position the shim stock and pull the quill handle and instant hole with almost no burr. Again, only for thin brass, and only for small holes up to about 3/16 diameter max. A little bit of oil on the punch will make it easier to get the stock off the punch after punching the hole. For 1/8 inch holes, I drill and ream an 1/8 inch hole in the steel die and use an 1/8 inch dowel for the punch after sharpening it. It will hold a better edge so gives a cleaner hole. If punching quite a few holes, it helps to relieve the back side of the die with a larger drill so the slugs don't bind up. Leave about 1/32 long section of the original hole.

A cad drawing of the part printed on a Laser printer and rubber cemented to the stock helps also. Laser printers are better at holding 1:1 dimensions on the print than inkjet printers. When punch holes by the above method, if the hole is accurately printed then it is easier to align the stock under the punch so the punch matches the drawing than trying to guess at centers.

Gail in NM

 

[ShopShoe]

Thank You GailinNM. I knew someone here would have a great tip like this, I love the help on this forum!

--ShopShoe

 

[krv3000]

HI well this may seem daft but I yous old food tins for shimming

 

[Tin Falcon]

Daft well maybe or not. I have heard of stories of using beer can material to patch skin on aircraft. IIRC slitz was preferred not the beer just the can material.
Tin

 

[Lakc]

3. A punch would be nice, but I don't think I'll use one enough to justify a good one: would the knock-off of the Roper-Whitney punch be useful, or just a waste of money? I can drill holes after sandwiching thin metal between wood or plastic, but sometimes the hole is rough or everything shifts.

--ShopShoe

I bought a Roper Whitney knockoff about 16 years ago. It has its faults and limitations, and I have throughly abused it, but I dont know how I would gotten along without it. At times, it has been worth its weight in Gold.

The cam bar was rivetted on backwards, the only thing that hurts is the pivot pin can fall out when changing the upper punch, but speaks of its eastern knock off heritage.

I have hammered on it with a 48oz ballpeen punching 11/32 holes in 1/8 mild steel, but it punched it.

 

[ShopShoe]

Thank you krv3000, Tin Falcon, and Lakc.

--ShopShoe