drill jug for drilling holes in washers

[Frank S]

I made this jig or fixture, to drill opposing holes in the face of some 3/4" hardened washers


It seems after I made these riser blocks I never run out of uses for them

I can clamp from 1 to a dozen washers in the fixture using 1 that it predrilled as the drill guide for locating the holes

Since the holes in the washers are slightly larger than 3/4" a 20mm bolt fits them very nicely holding them very close to concentrically centered

[NortonDommi]

Just today I explained to a younger friend,(Chef by Trade who I am teaching a bit about machines),about how washers are always a bit larger than the bolt or stud they are intended for and how by mixing Imperial and metric you can usually get a closer fit if needed.
The investment in those risers is certainly paying off.

[Frank S]

Just today I explained to a younger friend,(Chef by Trade who I am teaching a bit about machines),about how washers are always a bit larger than the bolt or stud they are intended for and how by mixing Imperial and metric you can usually get a closer fit if needed.
The investment in those risers is certainly paying off.

Also different grades of washers have different Id's and OD's, washers also have a top and a bottom when installing. On softer lower grade s this will be noted by the rounded edges on 1 side and sharp edges on the other, for hardened or machined washers the top is denoted by a slightly larger bevel on the ID, these rounded or beveled sides should always be installed next to the bolt heads, this is to lesson the possibility of creating a pinch moment with the fillet radius of the bolt head which could result in a stress fracture of the bolt. the hole Id of washers are larger than the bolt diameters for much the same reason.

[bob47907]

“… washers also have a top and a bottom when installing. On softer lower grade s this will be noted by the rounded edges on 1 side and sharp edges on the other…”

I never knew any of this! Thanks!

[DIYer]

Thanks Frank S! We've added your Washer Drilling Fixture to our Drilling and Drill Presses category,
as well as to your builder page: Frank S's Homemade Tools. Your receipt:

Washer Drilling Fixture by Frank S

tags: drilling, washer, fixture

[piper184]

Also different grades of washers have different Id's and OD's, washers also have a top and a bottom when installing. On softer lower grade s this will be noted by the rounded edges on 1 side and sharp edges on the other, for hardened or machined washers the top is denoted by a slightly larger bevel on the ID, these rounded or beveled sides should always be installed next to the bolt heads, this is to lesson the possibility of creating a pinch moment with the fillet radius of the bolt head which could result in a stress fracture of the bolt. the hole Id of washers are larger than the bolt diameters for much the same reason.

Thanks for the explanation Frank! I always just figured the lower grade washers were shaped that way because they were punched but not ground. The low grade washers always irk me that the center hole is nearly large enough for the next size bolt. Sometimes you need that "slop" but usually it just diminishes the effectiveness of the washer.

[Frank S]

Thanks for the explanation Frank! I always just figured the lower grade washers were shaped that way because they were punched but not ground. The low grade washers always irk me that the center hole is nearly large enough for the next size bolt. Sometimes you need that "slop" but usually it just diminishes the effectiveness of the washer.

If you take a look an any structural engineering books there will be a whole chapter on minimum and maximum hole tolerances for fasteners with and without washers and specifications for the types and thickness of washers suggested for drilled or burned holes
For most of my purpose's stamped steel washers are nothing more than a space filler or used as a cushion

[motorhead]

I think that, in part, you are referring to the differences between the SAE and USS washers as far as some of the differences go. Stainless steel washers can be a bit different in sizing as well.