How to hold flat washers to increase hole size

[Mr Fixit]

Hi Group,

I Know this is a simple question but I'm not thinking 🤔of a good solution.

I have a quantity of 1/4" flat washers that I want to keep the OD the same but need to increase the center to fit the application. I have tried to hold them in the vise and they catch and spin with a drill. I tried the lathe and the 3 jaw but it did the same thing or pushed them in the chuck. If I tighten the chuck they get flat sides.

I know I could make them but was trying to use what I have and just change the center ID to fit. I probably could buy some too, but what good is that when as a HSM I have the tools to hopefully make it work.

TX
Mr fixit for the family
Chris

[jmm03]

use a fender washer of the size hole you want clamped over the 1/4" washer. making a jig would be worth your time if you have a lot of them. A c- clamp with angles on the jaws will work but is cumbersome. Jim

[lbender]

For the lathe -- a pot chuck or emergency collet sized to match the washer OD and bore to size.

For the mill -- clamp a piece of scrap in the vice.
Bore a recess the OD of the washer with a depth less than the washer thickness also drill and tap for two mounting bolts located outside the recess.
Take a second piece of scrap and drill clearance holes that match the drill and tapped holes.
Place washer in recess and center drill over existing hole in washer.
Bolt down second scrap piece.
Drill thru.
Unbolt and place next washer in recess.
Repeat.

jmm03 types faster than I do.

[BCRider]

A flat vise much like this is a big help. This design is from one of the old Guy Lautard "Machinist's Bedside Readers" with a few slight changes to suit the stock I had on hand. The size of the square is picked to suit the drill press vise you use.

If you want to do a LOT of them or do the same job very regularly to the same OD washers I'd make a special one with a V or shallow flat bottomed bore to seat the washers to the same ID each time.

In fact..... assuming your DP table has a center hole something like this..... The khaki part is your DP table and the pink part is an easily turned center part to fit the table's clearance hole and given a centered thru hole and a slight counter bore which is a close but easy drop in fit for the OD of the washers. You want some way to hold the washer firmly so a make a long fish mouth hold down. I'd suggest you make the fish mouth bar longer than the outside of the table. Then drill a hole near to the inner end of one of the slots and add a bolt. To clamp the washer for drilling you just lift up firmly on the extended bar and the lips of the fish mouth lever the washer firmly down while drilling. Being a loose fit with the bar means it's easily slipped out of the way for switching washers.

Another option would be a shorter fish mouth bar with a fixed bolt/stud and hold down nut and a smooth wedge simply raises the free end to do the clamping. I'm thinking wedges or direct force simply because if you're doing lots these would be a faster option than any sort of threaded method which would be a lot of screwing around....

Of course another option for the fish mouth clamping bar if you're doing enough of them would be a cam action toggle handle.

Oh, and whatever you use for the center pivot for this hold down lever use a spring from below so it is self raising and thus easily swung away and back again.

[Mcgyver]

I'd used one of these, step chuck or pot chuck. Probably not very helpful if you don't have them already, but they are the cool tool for that sort of job. If you had a bunch to do, you could get the same setup with say a 5C emergency collet with a shallow bore of the right diameter.

Simple and cheap? piece of round stock with a shallow bore a little less than the washer thickness. In the end have a couple of screws such that when tightened the head of the screw holds the washer in the bore

[J Tiers]

The obvious "right" way is a step chuck. But you need the right step chuck, and the lathe that takes it, etc.

What "accuracy"?

My inclination for just use as a washer, would be to screw it to a piece of board with a hole under it, and use a "mechanics" general use taper reamer to increase the size. If I was more fussy, I'd run the reamer in from both sides.

Next up is the same, but use a step drill.

Last on the list, for reasonable accuracy, is holding it in a chuck, with a spacer under it, and cutting the hole larger.

And then, the step chuck, if I had one, for maximum accuracy. (I have exactly ONE, a WW type for the Boley)

[BCRider]

Accuracy for simply enlarging the middle holes in punched washers can be a little more forgiving than using a step chuck suggests. Although... if we have one it would be the quick and easy way as well as being very accurate....

I also have my doubts about the very shallow steps on those style of step jaw collets to hold the nasty shape from the punch process for cheap washers. I could see the drill easily ripping them away due to the roughness and bad angles on the edges of the cheaper made washers.

I saw Mcgyver's post and it immediately suggested this option to me if you're fresh out of step chucks. It would be held in your three jaw. Or if you have a 5C collet setup the little outer collar diameter just behind the front flange could be sized for a 7/8" or 3/4" 5C collet too. So a sub collet to fit a regular collet.

If used in the basic three jaw to have a fighting chance of staying fairly well centered I'd turn all the OD items first then part it off. Flip it and hold by the front collar and with a punch or file nick mark the Home jaw. Then drill or drill then bore to get the roughly .05 flex walls and turn the step for seating the washers. My 1/4" washers range in size from 9/16 to just over 5/8". So I've shown it as indicated. Just do it to fit what you have. Then remove and cut the flexure slots with your metal bandsaw or even a hack saw.



The downside to this method will be the number of starts and stops needed to do the job. And the time to slow down and speed up each time. All in all I'd say the drill press center hole holder would be nicer and faster since the table could be set for a height that gives you safe access to swap the washers and swing the clamp away and back while leaving the motor running the whole time. But work it would. My own preference though is clearly aimed at the drill press option.

[reggie_obe]

Roughly described: Square or rectangle of aluminum 2x1x1/2, drill, mill or bore a recess the OD of the washer, a little deeper than its thickness, drill a 7/16" hole through the plate, centered (approx.) in the recess, cut a slot through the plate from 1" end to the center hole. A washer placed in the recess should be held firmly when the plate is clamped in a vise and the recess collapses around the periphery.


BCRider, all common SAE and USS washers are punched, it'd the way they are made. Even 30 years ago, we regularly bought hundreds of pounds of punched washed in burlap bags made in India. They were cheap, but not because they were poor quality.

[masheenest]

You could bore a set of soft jaws for the three jaw chuck, or make a set of soft jaws for the milling vise.

[Bob La Londe]

On a mill or drill press? Machinable soft jaws in a vise. Doesn't need to be a mtach. Opposing Vs will hold it at 3 or 4 points.

On the lathe with a generic 3 jaw you just need a spider with a hole in it. Depending on the washer thickness I might do it without the spider. If it spins glue it.

Does it need to be clean? Maybe just blow it out with a torch or plasma cutter.

None of the above? Clamp the edge in a heavy vise and ream it out with a step drill.

There is always (almost) a way.

[Black Forest]

I think one question would be how many do you have to enlarge? That would dictate to me how much time to invest in fixturing.

[old mart]

Another way would be get some 1/4" penny washers, clamp down and make the hole to size. Then turn up a 3/8" stepped mandrel with a section for the washers to fit on and the end with a 1/4" thread for a nut. This will fit in the lathe chuck with some ordinary 1/4" washers in front and a nut. Fit in the lathe chuck and put several of the bored washers on the mandrel and turn the od to size.

[Bob Engelhardt]

How to hold flat washers to increase hole size

Vise grips, of course.

[BCRider]

.....BCRider, all common SAE and USS washers are punched, it'd the way they are made. Even 30 years ago, we regularly bought hundreds of pounds of punched washed in burlap bags made in India. They were cheap, but not because they were poor quality.

That's true. And I've seen a lot of good punched washers in my time. But the rougher ones pushed out by long suffering punches to reduce costs are a whole other new level of roughness. And sadly far more common these days. And the step collets I've seen only have very small step dimensions.

Roughly described: Square or rectangle of aluminum 2x1x1/2, drill, mill or bore a recess the OD of the washer, a little deeper than its thickness, drill a 7/16" hole through the plate, centered (approx.) in the recess, cut a slot through the plate from 1" end to the center hole. A washer placed in the recess should be held firmly when the plate is clamped in a vise and the recess collapses around the periphery.

A great option. And it only requires one part to be made. It could even be made from a piece of flat plate. And either given ledges with a mill to rest on the top of the vise jaws or used with parallels. Very neat idea. The holder could even be done with a piece of flat bar if the ledges are used. Just a flat version of your end on idea. Minimal machine work too.

For that matter these edge pinching ideas do not even require a counter bore. Three slightly leaning inward pins set in press fit holes on the flat or square bar version would serve just as well as a counter bore.



So lots of options. Pick the one that fits material on hand and that is most easily achieved. Or with the ideas given come up with something else that best suits.

Oh heck...just thought of an even easier washer holder that can be made from a very short length of scrap 1" round bar in the lathe and given a couple of easy flats to permit using it in the drill press vise.

[plunger]

I do this often. I have a standard 150mm three jaw chuck and the jaws have been bored on the front and its easy to set a washer or any thin workpiece in them . They are only bored about three mm but its enough .The washer is relatively true to the chuck when set up. This is similar to a soft jaw setup but its done in my hard jaws and is permanent obviously. Its very useful.