Surface Treatment of Installation Holes
Proof pressure data for Lee components is given for installation in bosses without any surface treatment having been applied.
Passivating stainless steel installation holes per MIL-S-5002 or ASTM A 967 has no effect on the performance of Lee components. For aluminum we recommend untreated installation holes, however anodized holes per MIL-A-8625 Type II are generally acceptable.
We do not approve the use of some proprietary surface treatments which include the deposition of solid lubricants such as Teflon®.
The Depth of the Reamed Hole
The "A" Dimension on the hole charts shows the depth of the reamed hole recommended for maximum holding power. When using the recommended "A" dimensions, the back end of the plug and pin will always be at least 0.010 inch below the surface of the material.
If it is desired to improve the appearance of the assembly, and maximum holding power is not a major concern, then the depth of the reamed hole can be made to equal the "M" dimension plus 0.010 inch.
In doing so, the finished installation will be flush with the material surface. However, this will cause a reduction in proof pressure of approximately 20% for short Lee Plugs and 15% for long Lee Plugs. This procedure is not recommended for High Strength Plugs.
Teflon is a registered trademark of E.I. Dupont de Nemours & Co., Inc.