What glue works best for creating knobs on levers ?

Hi, I have some etch brass little levers and need to make spherical knobs on the end. They already have a circular flat disc end dia 1mm but its flat, I need
it spherical. Best so far seems to be Aliphatic Resin which has more body than white wood glue, 5 dips into it and the knob looks really good, right size etc. and spherical (ball shape) BUT..after its dried its the same diameter as the disc end still but only now half the diameter sticking outward from that, and with more body at the top, not symetrical anymore but more like a hot air balloon shape ! Dipping again makes it look good but the same shrinkage gives it a similar though better form but its also now too big as you can see the etch brass disc within the translucent amber shape and not at its edge.
I need a glue that when dipped into, takes on the spherical shape and keeps to that as it dries. no shrinkage !
Also need to see whats happening when dunking so a coloured glue would be useful. This would also be great for making flat unrealistic etch brass representations of railings and rods etc, into something circular section again.
Steve
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[snip]
Epoxy.
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Hi Wayne, I have the dual syringe araldite rapid which on the packet doesnt say epoxy anywhere obvious, though in very small type says contains epoxy constituents. Internet search has word epoxy in same sentence as araldite rapid so I hope this is suitable.
Any tricks, should I warm it up or go with it cold ?
If this does what I hope, I shall be overjoyed, googled modelling knob making and found nothing, Even fellow modellers and stockists of modelling materials had no advice.
I wish there was a central depository of all modelling tips we could all add to !
many thanks.
Steve
wrote:

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Any glue in a dual syringe is almost certainly an epoxy. With "rapid" in the name, it's probably a 5-minute epoxy.
I suggest cleaning the brass part first with alcohol or lacquer thinner, and lightly sanding it with 600 grit sandpaper, so the epoxy can form a tighter bond to the metal. It may also help to stick the part into a pin vise or the end of a dowel, to make it easier to hold.
The epoxy should be at room temperature. Squeeze out a small blob, say about the size of a small grape, onto a piece of cardboard and mix thoroughly with a toothpick. Then use the toothpick to transfer some epoxy to the brass part, or just dip the part into the epoxy, and wait for it to harden. If the epoxy starts to sag, twirl the part slowly to keep it round until it sets.
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merlin snipped-for-privacy@REMOVETHIShotmail.com says...

Gap filling superglue makes good knobs. Build it up in layers one side at a time.
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Hi Jessie,
strangely enough just tried that, but unlike the 5 dips and its done aliphatic resin which creates a knob superbly, but disappoints after drying, the gap filling glue (I did have a medium one though) just didnt seem to add anymore with each dip, and blobbing it on with a wire sees a small amount each time and a pimple results, maybe a larger depositing device than a wire was needed. One needs to cure it between dips maybe, but doing so is tricky without wrecking it. Applying to each side separately can see an asymmetry result. The superglue was looking good until accelerator was used to enable a next dip and then it went out of shape. Result I got was not even symetrical even after dipping which surprised me, so superglue seemed a rougher ride than the resin.
Maybe its a question of one side at a time and a larger depositor and let it naturally cure ?
It seems like there is one way and knowing it is the secrety to success.
Epoxy sounds good, so now to try that.
Steve
<Jessie_C> wrote in message says...

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I tend to use the bottle, and carefully drop a drop on the tip of the lever. If I use an applicator, one the same size of the knob works well. I always keep the ends of stretched sprues around for that, and trim them to size as needed.
Have fun experimenting with the epoxy : )
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Phew what a fiddle. Epoxy rapid , dip the part in, then after a few dips its not developing more than a rugby ball shape, so drip on more per side with a wire, but it tends to pull off as much as goes on.
Look at results next day and an elongated ball,the trouble with working each side separately, but cant file it as its sort of rubbery. Not gone like stone or filler.
need to get shape just right then,,,so start again !
Try again with standard araldite, more working time, thinned with Isopropyl alcohol, very runny. drip it on each side, giving the dollop on the wire a quick 2 sec held in front of heater so resin comes off easier without pulling resin from the existing ball shape, but that existing ball shape tends to go uphill against gravity...honest ! what was a lovely sphere is now going pear shaped.
put aside to set away from heat, reckon heat is causing it to 'rise', but after a while its back to rugby ball shape ! It also has tried to go uphill, thats most odd.
I have added a little more to each side, three times now, each time heating the dollop on the wire before introducing it to the existing lever blob, that way it comes off the wire without pulling the resin off the lever so much !
Why though is it shrinking, araldite rapid didnt shrink at all. Maybe its the Isopropyl alcohol evaporating out reducing the bulk , I only used 5 drips from a pipette into my mix which filled the top of a humbrol tinlet lid. Bacofoil lined :-)
Maybe the Rapid with just heat is the way to go ?
Why are the no articles on this sort of thing in mags ?
Steve
<Jessie_C> wrote in message >I tend to use the bottle, and carefully drop a drop on the tip of the

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merlin snipped-for-privacy@REMOVETHIShotmail.com says...

I just had another thought. Have you tried Krystal clear? It's got really good surface tension and makes nice ball shapes.
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Jessie_C wrote:

I was going to suggest that, but I',m sure how Krystal Clear is any different from thickened white glue...
--
- Rufus

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"> I have some etch brass little levers and need to make spherical knobs on the

You haven't said what scale you're working in, but 1mm ball must make the actual lever arm really thin. For something slightly larger you may consider sewing pins that come with a round (spherical) head. I measured some in my wife's sewing kit and the spherical heads are just below 1/16th inch in diameter and really round. 1/16 is about 1.58mm so let's call it 1.5mm. There are others at different diameters. Note I'm not talking about pins with flat circular heads like nails. These are spheres, and the stainless steel pin is tough. I've also seen similar pins maybe even smaller heads used to package dress shirts although they seem to be using more plastic clips these days.
Val Kraut
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Or try your friendly art supply store (Michaels here in CA) and look in the beadwork section. Seems like I've seen some around 1 mm there.
T2

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I've found much useful stuff in Michaels and a local fabric and craft store, particularly in the make your own jewelry supplies, not just beads but things that can be used as hinges, latches etc. It's like I walk around Home Depot inventing projects as I discover tools or supplies, here I wander around waiting for my wife to buy her craft and scrapbooking supplies. Also some items useful for diorama groundwork with the dried flower and plant stuff. I've got a small collection of things that could be useful on a future project (and won;t be available by the time I do it).
Val Kraut
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Hi, 1/32 scale aircraft consoles, 1mm and no bigger, araldite rapid found as the best, in all the tests..
Pins would be far too big and crude here, then you have the trouble of geting the ball onto a slab sided lever.. as for 1/48 again araldite rapid I would assume.
best to act quick, once its going a bit tacky forget it ! Mix more, fast fast fast is the trick. a drop on one side of a circular ebrass receiving area (designed my own ebrass levers)
else try the dip method and move it about keeping a ball shape and form it that way.
Steve


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