|martyn nutland||06/04/2019 12:41:58|
|95 forum posts|
Does anyone make tab washers in their workshop, and know an easy way to do so that's not like taking a steam hammer, the size of Big Geordie, to crack a very small walnut? I know your going to say: ' tab washers cost buttons, so why bother'. True; but my supplier makes them from far too hard a steel and when they are close behind a nut and tight against a ball race (my context) they are nigh on impossible to bend neatly without damaging the nut and/or bearing.
Soften them by heating. Yes? But to what colour and quench?
Or, could you do it like this? The Big Geordie and nut method! The principal difficulty as I see it is the internal tab. What if you took a piece of aluminium bar, turned to the desired outside diameter of the washer and bored to the inside diameter less the width of the tab. Now set up the workpiece on a rotary table and mill round with an endmill for, say, 350° of the bore - or any circumference that left the appropriate tab width. Could you now slice off as many washers as required, as thinly as practicable, with a slitting saw and grind them down to an appropriate, bendable thickness.
|David George 1||06/04/2019 17:30:32|
783 forum posts
Hi Martyn tab washers are there to prevent a nut or similar unscrewing and if they are too soft they would not do their job or may break if hardened wrongly. I don't know the results of a nut coming undone have you thought of wireing the nuts instead it can be easier to access and does the same job.
|Speedy Builder5||06/04/2019 19:04:15|
|1740 forum posts|
I have made them from ordinary mild steel sheet for my Austin 7. None have come undone - So far.
3591 forum posts
Don't make them from aluminium; the tab will break off too easily. Cut them out of sheet steel with tin snips. 1mm thick should do the job but a bit thicker would be better. Machining a bar and cutting slices as you suggest would have the grain of the metal going the wrong way and be very weak and prone to tab snapping off.
I can't visualize your exact application without pic but one trick is to slightly bend the tab up a little (30 - 45 deg?) before installation so you can then get a screwdriver or plier jaw in behind it when installed in situ.
The best method to bend up the tab, if there is access, is to use a pair of slip joint pliers (aka multi-grips, parrot nose pliers or water pump pliers depending on side of the pond etc) with one jaw on the far side of the nut and one on the tab, with the the pliers oriented so the longitudinal axis of the plier jaws is in line with the longitudinal axis of the bolt. You then use a levering action on the pliers rather than a squeezing one to bend the tab up.
I suppose for tiny model size stuff you could use fine long nose pliers in the same way.
And you won't soften steel tabs by quenching. Heat to cherry red and allow to cool slowly to anneal. But I really don't think that is your problem. There is no reason a lock tag would be particularly hard other than perhaps an insignificant area on the very edge where it was punched out of flat sheet.
Edited By Hopper on 07/04/2019 02:28:30
Edited By Hopper on 07/04/2019 02:32:18
|Michael Gilligan||07/04/2019 06:49:47|
13053 forum posts
These people give specifications for many standard tab washers: **LINK**
The idea of [single use] tab washers has been well-proven over many decades, so I suspect that your problem might be attributable to your supplier's poor choice of material.
15321 forum posts
You don't want to quench anything to make it easier to bend. Heat to red heat and then allow to cool slowly, job done.
|martyn nutland||07/04/2019 09:54:09|
|95 forum posts|
Good advice and tips I shall employ.
|vintage engineer||07/04/2019 10:10:26|
124 forum posts
I get them laser cut on a tree and break them off.
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