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Post by delaplume on Sept 30, 2020 9:49:30 GMT
Hi Roger,
a) Combine the last 2 ideas with the punch giving the accurate hole, and the bulk turning to give the O/D required.....
OR
b) Try an On-line search.... you never know, there just might be something out there at, or near to your requirements...
Great job on the paintwork matey !!........I can see you taking in contract work when you retire !!
PS}---- the old fashioned Fly Press is ideal for this type of work....
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stevep
Elder Statesman
Posts: 1,070
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Post by stevep on Sept 30, 2020 10:37:32 GMT
Hi Ed, I'm not sure I'd be able to do that well enough, although the idea is appealing. Roger, many years ago I made a simple jig for cutting washers. It was intended for copper washers to go underneath boiler fittings, but would work well with shim. It consists of a block of steel with reamed holes, and a sawcut which cuts across the reamed holes. Put the material in the slit, and using a piece of squared off silver steel of the same size as the reamed hole, tap it through, and a disc is cut out. If you make one hole the size of your bolt, and then in a separate hole of the required OD, use a punch with a 'nose' the size of the first hole, and you can align the fist hole on the 'nose, and then punch out a washer. Mine is very crude, but remarkably effective. I'm sure yours would be much more elegant! :-)
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Post by Roger on Sept 30, 2020 10:49:15 GMT
Hi Roger, a) Combine the last 2 ideas with the punch giving the accurate hole, and the bulk turning to give the O/D required..... OR b) Try an On-line search.... you never know, there just might be something out there at, or near to your requirements... Great job on the paintwork matey !!........I can see you taking in contract work when you retire !! PS}---- the old fashioned Fly Press is ideal for this type of work.... Hi Alan, Punching something this thin is tricky. If you have a shear style punch and die with an inner and outer, the ID od 3mm and OD of 4mm makes it tiny and fragile. You need clearance, but that can't be much since the material is so thin. If you punch it onto a flat compliant surface, you're going to struggle to get a decent edge and the punch probably won't last two minutes. I'm just going to make a thin tube and part them off to length, I think that's the easiest way to make them.
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Post by cnr6400 on Sept 30, 2020 10:59:42 GMT
In industry, washer making in quantity is done in compound dies. A good animation of how these work is at the following link. Note that in this type of tool any thickness of stock can be cut into a distortion free washer or shim because the stock is fully supported across the tool faces. For very thin stock very small cutting clearances are needed to get a clean burr free edge. For stable tooling, the rule of thumb re the possible min ratio of ID to OD is that the distance ID to OD should be 3 times material thickness min. In other words don't try and make a washer 0.5 mm thick and an ID to OD face distance of 0.3 mm. A 1.5 mm wide face or wider ID to OD will work fine in 0.5 mm stock. youtu.be/LKEG3p3yx1g?t=7For the home workshop, for making just a few special washers or shims, such dies can be simplified and made to operate in a vise or arbour press by extending the top outer punch downward with a skirt that rides an increased lower section OD of the bottom centre die. All parts turned easily on the lathe, suitable die springs are available from Producto Corp, Danly, and other die making suppliers, and industrial suppliers. Hope this is useful.
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Post by simplyloco on Sept 30, 2020 12:16:11 GMT
Roger IIRC Chris Vine machined a very slight taper under the mating bolt heads of those that mattered. Much easier than die making! John
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Post by terrier060 on Sept 30, 2020 12:46:44 GMT
Punching is very easy. We do it in clock and watchmaking all the time. For the hole a simple circular punch which is held vertically and tapped with a hammer into a receptive hole. Just need a larger one for the outside of the washer. Brass shim would be ideal, as it does not rust and the washers only need to be the diameter of the flats on the nuts/bolts so are hidden. Very quick to make and certainly not difficult to make the punch for you Roger.
I am away at the moment so can't show you a photo of the punch. Ed
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Post by Roger on Sept 30, 2020 12:54:28 GMT
Roger IIRC Chris Vine machined a very slight taper under the mating bolt heads of those that mattered. Much easier than die making! John Hi John, That's what I was going to do, but I think this will cause less damage to the paint because the bolt will have something slippery and firm to press against which can stay stationary rather than tear into the paint.
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Post by terrier060 on Sept 30, 2020 13:02:17 GMT
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Post by Roger on Sept 30, 2020 13:26:20 GMT
Thanks Ed, I think I can see what those are. I've just made 8 from a piece of 4mm Silver Steel with a 3mm hole in it, parted off to 0.2mm thick with a 1mm parting tool. That seems to have worked out fine, so I'll probably stick with that.
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don9f
Statesman
Les Warnett 9F, Martin Evans “Jinty”, a part built “Austin 7” and now a part built Springbok B1.
Posts: 960
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Post by don9f on Sept 30, 2020 15:44:40 GMT
Hi Roger, I used to fly model helicopters and some of the rotor heads I assembled, came with a number of very thin, well fitting washers to use to make tiny adjustments to the fit of bearings etc. on shafts. I have no idea these days if such things can be bought separately but somewhere “out there” these things are being made. I might have a few of say 3mm bore that I could lay my hands on.
Cheers Don
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Post by Roger on Sept 30, 2020 16:25:13 GMT
Hi Roger, I used to fly model helicopters and some of the rotor heads I assembled, came with a number of very thin, well fitting washers to use to make tiny adjustments to the fit of bearings etc. on shafts. I have no idea these days if such things can be bought separately but somewhere “out there” these things are being made. I might have a few of say 3mm bore that I could lay my hands on. Cheers Don Thanks for that Don. If the ones I'm making don't turn out good enough, I'll have a look and see if I can find those.
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Post by Roger on Sept 30, 2020 22:43:54 GMT
Chris Vine in his book shows how he sprayed the frames using a vertical mount, and this is what I want to do to get the best angle for spraying the buffer beams. The way I currently have it makes it hard to see what's going on and the paint surfaces are vertical. Although I can turn that over, it would just be much easier if they were horizontal. So to that end, I've quickly designed a pair of 3D printed clamps that are handed. 20200930_115034 by Roger Froud, on Flickr I've used an M6 square nut to take the clamping screw. The 'U' shapes is 10mm across. 20200930_211451 by Roger Froud, on Flickr And this is where they go, on the front of the bench. 20200930_211503 by Roger Froud, on Flickr So you can see that those two M10 studded rods can be trapped between the clamps so that this arrangement can be stood on its end on the floor and not fall over. I'll strip off the motor and handle, those won't be required. 20200930_212036 by Roger Froud, on Flickr I'll leave the paint to dry for another 24 hours before masking up the buffers, and then I'll give it a try.
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dscott
Elder Statesman
Posts: 2,438
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Post by dscott on Oct 1, 2020 0:26:24 GMT
PS}---- the old fashioned Fly Press is ideal for this type of work....[/quote]
I could hire it out such a sweet little thing. Still cant lift it. It has taken to living on the end of the third Raglan.
David and Lily
Punches and dies plus material could be accepted for a production run!!!!
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Post by chris vine on Oct 1, 2020 9:22:13 GMT
Hi Roger,
Yes, the little taper angle on the undersides of model bolts does work well in protecting the paint. For stronger needs, cylinders etc, I think a washer might be better so you can tighten it up properly. However for most fixings, eg running boards to brackets, the little bolts only need doing up gently. For these you may find that the tapered underside works just fine.
Chris.
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Post by Roger on Oct 1, 2020 9:59:58 GMT
Hi Roger, Yes, the little taper angle on the undersides of model bolts does work well in protecting the paint. For stronger needs, cylinders etc, I think a washer might be better so you can tighten it up properly. However for most fixings, eg running boards to brackets, the little bolts only need doing up gently. For these you may find that the tapered underside works just fine. Chris. Hi Chris, Thanks for that. The ones that really show are the smokebox saddle bolts and the ones that hold the brake stretcher. Both of those ought to be fairly tight, so maybe a really thin AF sized washer would be better for those?
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Post by chris vine on Oct 1, 2020 13:21:34 GMT
I think you are right. On Bongo, all these tight bits, cylinders, stretchers, smokebox saddle etc, were in place and tight before painting. For you it is different.
You will be able to make washers better and quicker than messing around trying to find a supplier of exactly what you want!! Stupid idea: Could you machine them on your mill out of some shim stock? Maybe on a mag chuck or double sided tape. Just leaving a thou' or two, (sorry a few microns!) to push them out of the sheet.
Chris.
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Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Oct 2, 2020 0:26:16 GMT
I think you are right. On Bongo, all these tight bits, cylinders, stretchers, smokebox saddle etc, were in place and tight before painting. For you it is different. You will be able to make washers better and quicker than messing around trying to find a supplier of exactly what you want!! Stupid idea: Could you machine them on your mill out of some shim stock? Maybe on a mag chuck or double sided tape. Just leaving a thou' or two, (sorry a few microns!) to push them out of the sheet. Chris. A problem with assembling after painting, is not so much damaging the paint film (though I can undertand how annoying that might be) but if you don't damage the paint, your bolts will not stay tight. The paint film is soft (relative to metal) and will try to squeeze out until the pressure of the nut/washer has been relieved. And you still have to go back and paint the nuts and bolt heads after assembly... Gary
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Post by chris vine on Oct 2, 2020 6:49:20 GMT
That is correct, Gary. That is why I didn't dismantle the cylinders, motion brackets, stretchers etc for painting. Maybe Roger could make a tiny, hand-held, counterboring-like tool. It could just remove the paint for a diameter across the corners of the hex heads. Then they will stay tight and the paint won't get dragged all over the place as bolts are tightened.
Chris.
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Post by Roger on Oct 2, 2020 7:14:33 GMT
I think you are right. On Bongo, all these tight bits, cylinders, stretchers, smokebox saddle etc, were in place and tight before painting. For you it is different. You will be able to make washers better and quicker than messing around trying to find a supplier of exactly what you want!! Stupid idea: Could you machine them on your mill out of some shim stock? Maybe on a mag chuck or double sided tape. Just leaving a thou' or two, (sorry a few microns!) to push them out of the sheet. Chris. A problem with assembling after painting, is not so much damaging the paint film (though I can undertand how annoying that might be) but if you don't damage the paint, your bolts will not stay tight. The paint film is soft (relative to metal) and will try to squeeze out until the pressure of the nut/washer has been relieved. And you still have to go back and paint the nuts and bolt heads after assembly... Gary Hi Gary, As with all things Engineering, it's a compromise. The problem with spraying an assembly is that it's much more difficult to do that and get an acceptable finish all over. Some folk seem to have a gift for achieving this, learned over decades of experience. For a one off project, I thought it was simply too difficult having tried that and been disappointed with the result. Each to their own, they all have their pros and cons.
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Post by Roger on Oct 2, 2020 7:17:11 GMT
That is correct, Gary. That is why I didn't dismantle the cylinders, motion brackets, stretchers etc for painting. Maybe Roger could make a tiny, hand-held, counterboring-like tool. It could just remove the paint for a diameter across the corners of the hex heads. Then they will stay tight and the paint won't get dragged all over the place as bolts are tightened. Chris. Hi Chris, That might prove to be a good solution, I'll probably try that.
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