What is best way to create 0.3mm dia blobs on plastic ?

Hi, I need to place some bolts on a 15thou piece of plastic card, at 1/32 scale, a blob as opposed to a hexagon is enough as thats only 0.46mm dia. Also
rivets in a row, 7mm dome head is 0.2mm at that scale. White PVA looks good but then as it dries the top sinks in. Any ideas how best to achieve this ? Any fillers that would blob on in those sizes ? Anything you know that does the job ? It needs something that doesnt shrink as it dries. Hole punches are too big for this scale. Steve
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Steve wrote:

If it's the plastic card, try the time honoured method of embossing the domes from behind with a ball pen.
Vedran
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El Viejo Dragon wrote:

Indeed, a ball point pen makes a neat embossing tool. I made a little jig that holds pen point vertical and an adjustable rail that allow me to slide card stock along in a nice straight line.
For work on regular injection-molded kits I use the white glue for small rivet heads, use aftermarket rivet and bolt heads for larger ones. These are available in the model railroad section of bigger hobby shops.
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Hi, thanks for the ideas, embossing plastic card 15thou thick from the back to produce bolts and rivets 0.46mm dia and 0.2mm dia ...sorry but it wouldnt work for those sizes. 15thou card is quite thick and a 1mm dia rivet might be a result with a ball pen but not 0.2mm and 0.46mm. In my case these nuts relate to a bracket affixed to the inside of the sheet, so any embossing is out of the question as the bracket is in place.
I have tried the R/C Modellers Craft Glue, the spots dont have their centres dip in when dry, but they do flatten down somewhat, looked good when first applied. I suppose a second and perhaps third application exactly on top of the first might produce a decent dome, but getting a hit in the same place is tricky, I am using the blunt end of a very fine drill bit to apply the glue, just touching the glue blob onto the card and not letting the metal meet the plastic.
I tried Mr Surfacer 500, but it tends to string a little, not bad but not as easy as the white glue, just wish the white glue didnt shrink in size and lose the initial domed effect.
I have a hexagonal shape punch and die set by Reheat RH142 but the smallest bolt head is twice as big as I need at 0.64mm flat faces. 5thou plastic card by evergreen gave a hexagon on three sides but a rounded fourth side. Tin foil gave a decent hexagon, less elasticity in the media !
Steve.

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You could try these -
http://www.archertransfers.com/catSurfaceDetails.html
In particular, the .011" (.28mm) and/or .014" (.36mm) rivet transfers - check all of the sheets, because they seem to come in various sizes and pitches on each sheet. I've never used these, but you basically rub them on and then paint over them, giving just enough lift to provide flush rivet detail.
Another way would be to use a Waldron punch and tape or aluminum foil - punch the dot out of the tape or foil and place it.
There's always Grant Line nuts, bolts, rivets, which I have used and are comparatively easy to use since they are plastic and you can use your usual glue with them -
http://www.grandtline.com/model_railroad/augmentables_pages.htm
Then there's these -
http://www.galtran.com/ScaleNutsandBolts/ScaleNutsandBoltsProductPage.htm
http://www.scalehardware.com /
--
- Rufus

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Cheers Rufus, Afraid though the bolt heads like grant are twice the size of those I need. The decal sheet is a thought, though a lot of money for the few I need. Good product to know about. The fasteners site, awesome, again nothing small enough, 18thou (0.46mm) would probably be impossible to engineer. I wondered about creating 0.46mm size hex holes in brass (means making an e-brass sheet) and extruding sprue or filler like milliput through it, then slicing slivers off. Trouble is that may not work and the slices may be impossible to do, but delays the build for weeks. Still stumped. At 1/32 the hexagons are visible but tricky to make. looks like its to be a blob of glue ! I may attempt trimming down the reheat die punched heads...perhaps not !
Steve

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Rufus has it right -- the Archer Fine Transfers are just about what you want and will last for a few projects (unless you are building WW I tanks or Gauge 1 steam locomotives!)M
You could also use "salami sliced" 0.020" Evergreen styrene rodding. A thin slice with a dot of liquid cement tends to melt and "blob" out very nicely.
Cookie Sewell
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Now that's a thought - an etched brass template and putty. You'd only need to tape the template in place, putty through it, and then remove. You'd likely want to use a rather "stiff" putty...or maybe even a slurry of bits of sprue and liquid glue.
Hex shape is a hard one - I've been looking for a set of Historex punches here for some time, but I both can't find a source and see that they are ridiculously expensive. If you have a hex punch of the right size, you could try punching them out of ordinary decal sheet in lieu of using the Archer dry transfers. I've done that with my Waldron round punches for things like red fuel caps, missile markings, etc. Or punch them out of Bare Metal foil sheet.
There's also quite a bit of etched fastener stuff out there meant for scale cars - depending on how many you need, may want to try looking in the auto detail bins at your local.
--
- Rufus

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Rufus,
Best bet is to use the Plastruct styrene hex rod and "salami slice" it with a NWSL "Chopper". Takes a bit of practice to get the cuts even but works a lot better and is much cheaper and easier to use.
Cookie Sewell
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snipped-for-privacy@aol.com wrote:

Yeah - that would work too...I'd suggest blocking the backside. Like setting up a guideway on the Chopper, and using a backing block.
...I'm going to have to look over the Plastruct line again. I recall that stuff being ABS and never being able to find a glues that would work with it...been using Evergreen styrene ever since.
--
- Rufus

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: snipped-for-privacy@aol.com wrote: : :> Best bet is to use the Plastruct styrene hex rod and "salami slice" it :> with a NWSL "Chopper". Takes a bit of practice to get the cuts even :> but works a lot better and is much cheaper and easier to use. :> :> Cookie Sewell : : Yeah - that would work too...I'd suggest blocking the backside. Like : setting up a guideway on the Chopper, and using a backing block. :     Plastruct does offer 0.020" hex rod, which is 0.003mm larger than what the OP wanted originally, and it is in styrene.
    Problem is, Walthers is OOS, and Plastruct doesn't sell retail, so unless you have somebody that has the required rod, it is a bit of a problem still.
                            Bruce
--
------------------------------------------------------------------------
"I like bad!" Bruce Burden Austin, TX.
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Steve, here are some photoetched 0.020" hex fasteners: PTMC 7 Nuts & Bolts/Bolt Heads (any scale)(photoetch)(please specify size).. Use these any place a nut and bolt or bolt head should go. (.040 - small), (.030 - smaller), (.020 - smallest)
http://www.protechmodelparts.com/carpartspics/ptmc7.jpg
Peteski
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Hi, Peteski, thats certainly an option, size is ok, USA location and payment/time as I am UK is a nuisance and customs may add to the cost. Tab free is excellent. I may well try for a sheet. Many uses.
Bruce, <<Plastruct does offer 0.020" hex rod, which is 0.003mm larger than what the OP wanted originally, and it is in styrene.>>
I make that 0.26mm, 0.02" is 0.508mm and I needed 0.31mm, difference of 0.198mm, almost double the size I need. However again its good to know they do rod down to that size and in a plastic that will glue. Like Rufus said, Plastruct used to frustrate me as it wouldnt stick, even with the correct glues.
I looked at my Reheat hole punch set and found that the smallest there was 0.41mm and the results from it, having had to drill out the guide hole in the transparent upper part of the jig first as it was undersized, looked acceptable and being flat topped, could be accepted at that small size as a bolt head. I think one would be pushing the limits of punching plastic sheet with the little bit of elasticity it has and expecting a crips perfect hexagon. Aluminium foil may be better but at 5 thou would it yield too much resistance ?
I shall paint the receiving area with an enamel based (for slow dry time) varnish and place them on.
I find that you can read countless articles in mags on kit build reviews but they never prepare you for these tasks, a 'not so FAQ' site with questions and answers with illustrations on things like creating dome head rivets at 1/32 scale, bolt heads and tails, filing sticks 10thou and 5 thou thick, or 2mm wide etc. You can't buy them , always lollipop stick size !
The rivets will have to be either the decal 3D sheet or blobs of dense white glue.
Steve

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Use sludge. http://www.tri-art.ca/en/products/sludge/ I get mine from the artist's supplies shop.
This is a fantastic product for quirky applications. Flat on flat surface adhesion is as good as any glue without the problem of glue melting/softening/fogging the material. If you don't like it just pull it apart and rub off or use a wood pick to remove the dried sludge. Not even the paint will be damaged. Use Sludge to secure clear parts (cockpits, windshields), to adhere irregular fully painted parts (eg. personal equipment such as water bottles, bayonets, spades, sidearms) to figures; equipment, baggage and accessories to vehicle sides. I have even used sSudge to attach nylon strands to replace the molded horse's tail and mane. It will bond glue incompatible materials such as plastic to wood to metal to organic stuff such as feathers (indispensible for building dioramas.)
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Steve wrote:

Have you tried sugar or salt ? I've gotten by using both before and from a distance it worked.
Sorry, I've been a way a while....
AM
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wondered where your nym went...glad you're back.
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Steve wrote:

I bought a set of Jewellers beading punches and punch rivets out of heavy foil thin plastic sheet or even lead foil from dental xrays . Item 1 on this link
http://www.hoj.com.au/images/catalogue/aa287cc50eec40daad020f492bb5e461.jpg
They are punches with a concave domed end and will produce a small domed rivet of what ever size the punch is .I bought the 23 punch set and handle , they work great for also embossing the big screw heads on the stug roof plates. I know I have seen them on US websites of Jewellwers suppliers.
Alternativly ,get a set of those fine drills from Micromark . No 61 -80 ,place a piece of thick foil onto one of those vinyl erasers and use the blunt end of the drill of the size required to punch the rivet from the the foil , you will have to dig the rivet out of the eraser . I have made hundreds of rivets in a few minutes ,what I don't use I keep in those plastic film containers with the size written on them for further projects . I have been making scale rivets with these two methods for years ,so I know they work. For larger Hex bolt heads I use the hex plastic rod from Evergreen or Plastrut (forget which now) and slice it with a sharp razor blade , I glue them onto thick plastic card temoprarily with white glue and then sand them all together to the required thickness.
--
Kevin (Bluey)
"I'm not young enough to know everything."
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There is very likely a hypodermic needle of the diameter you need from the veterinary supplies or a farm supplies shop. You can buy them without any staff member freaking out. You can probably use it as a punch (squared off sharpened tip) or as an extruder for a string of material of the correct diameter that you can slice to the desired thickness to make your boltheads. The extrusion material that come to mind is resin (although I have not worked with resin yet.)
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PaPa Peng wrote:

Oooooo...great suggestion! I'd use it to punch foil rounds - like Baremetal foil that I could simply stick on, or thicker stuff that I'd glue with a foil adhesive...dat would woik!
--
- Rufus

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