Cacique Caribe | 16 Jan 2011 2:35 a.m. PST |
The ones with the cut-out circles: link I haven't found them in either Plastruct or Evergreen's websites. Do they even make them? Thanks, Dan TMP link |
Colin Hagreen | 16 Jan 2011 3:21 a.m. PST |
Not seen any
but that's an inspiring picture for my 15mm sci-fi stuff
|
apathostic | 16 Jan 2011 3:39 a.m. PST |
You might just have to buy a punch and die set, and go old school on a piece of plasticard. Have been trying to buy this stuff as well. |
Given up for good | 16 Jan 2011 5:02 a.m. PST |
Wonder if Ken Litko can make you some up out of wood? Only other thought is architects supplies rather than modelling suppliers. Main issue will be I-beams are normally flat not curved. Andrew Main site: blog.kings-sleep.me.uk |
Goose666 | 16 Jan 2011 5:12 a.m. PST |
I would say, best plan to make a master from plasticard sheet with a punch kit and then cast in a two piece resin cast. I would make sure the mould split long the same axis as the central spine with the holes. That way you can sand down the seem/flash more easily. Though the lightening holes could be a problem with getting the resin to flow around them. You might find it easier to cast it solid and drill out this later in the resin. |
Cosmic Reset | 16 Jan 2011 6:02 a.m. PST |
I've made them from sheet and strip styrene. Started by make in a simple jig out of basswood, drilled pilot wholes with a 1/16" (or slightly smaller) bit, and drilled the final holes with a unibit. The unibit is really nice for drilling the plastic as you don't get any ripping or spalling effect on the backside of the hole, though they may not go small enough for 15mm. |
Given up for good | 16 Jan 2011 6:05 a.m. PST |
Need new glasses – just saw: drilled pilot whales not drilled pilot wholes |
Cacique Caribe | 16 Jan 2011 6:38 a.m. PST |
LOL Dan PS. Colin Hagreen, if you like that image, check out the many others in my second link. |
ming31 | 16 Jan 2011 7:29 a.m. PST |
Couldn't you just heat form some ? use a large coffe can and some boiling water . |
ScoutII | 16 Jan 2011 7:49 a.m. PST |
Is your main desire the holes or the bend? I have built ones with holes before – not too difficult. Take your strip styrene and use a hole punch the size you want, pop the holes. Be sure to do a layout ahead of the time to make sure you have them in the right positions. After that is done – use two smaller strips and glue them to the top and bottom. Curved would be the same deal – only you will want to cut your own primary strip from a larger sheet. Use one of the large circle cutters to cut the curve you want. Again – lay it out first with a compass in order to make sure you get everything in the right spot. Cut the outer curve. Punch the holes. Cut the inner curve and then glue on the flanges. Should only be a few minutes work from start to finish. |
Cacique Caribe | 16 Jan 2011 7:51 a.m. PST |
"Is your main desire the holes or the bend?" The nice clean, properly spaced and lined-up holes, really. I just read something that made me think. If all else fails, I may even try using the plastic canvas pattern that is used here to make rivets: TMP link Except I'll probably use a small hole punch and skip every other square. Thanks, Dan |
ScoutII | 16 Jan 2011 8:00 a.m. PST |
So clean properly spaced holes on a straight bar
drill press. |
elsyrsyn | 16 Jan 2011 8:11 a.m. PST |
Wonder if Ken Litko can make you some up out of wood? Or, if it's worth the effort to you, you could draw them up yourself, exactly as you want them, and have them laser cut. It's not terribly expensive, but it's probably not worth it if there's something reasonably close you can get off-the-shelf. Doug |
Cacique Caribe | 16 Jan 2011 8:13 a.m. PST |
ScoutII, Those are going to be some pretty expensive holes. :) link Dan |
28mmMan | 16 Jan 2011 8:50 a.m. PST |
A couple thoughts: Drill bits
use sharp/new bits for the project
buy good bits or several of the same cheap bits
dull or misshapen will catch or redirect, breaking and cracking the plastic. Unibit stepping bit
one of my favorite tools picture , again new is best (mine have been in use for all manner of metals, fiberglass, starboard, etc.)
cheap unibits would be fine for this project of cutting plastic but not much else as they are not all that cheap
a dull or well used step bit can wobble and tear uneven holes
keep in mind that step bits cut in percentages/fractions and if you step too far then your entry side will be tapered into a larger hole as it starts cutting the next size up. Dan, for your needs I would recommend a decent vice with soft lips like this one link (craftsman tools are expensive, this is just a pic example :) clamp the flat edges and drill with a variable speed drill like a dremel link (you do not need the whole dremel package as they would have you think, just a simple lightweight tool IMO). Just keep in mind this when cutting plastics: high speed will cut by melting, which can and usually will seal itself behind the cut :( slow speed will tend to be unforgiving with angles and can catch/grab :( dull tool edges are bad :( keep a small cup of water to cool the cutting bits :) preparation is key, 90-95%, the actual cutting is only 05-10% of the effort :) Good luck, this is an easy process
find a close piece of scrap plastic to practice with :) |
ScoutII | 16 Jan 2011 9:02 a.m. PST |
Drill bits
use sharp/new bits for the project
buy good bits or several of the same cheap bits
dull or misshapen will catch or redirect, breaking and cracking the plastic. I would actually say a brad point bit – new (or recently sharpened). Since they have a center point – you can precisely align them. The outer cutters on the brad points will score and cut through styrene quite well. I have used them on acrylic and styrene in the past – and they actually cut well enough that you can twist the bit by hand in order to cut/drill the holes. Those are going to be some pretty expensive holes. :) Ask around the neighborhood. You might be surprised that the guy next door has one in his garage he will let you use for a second. That said – my first suggestion is probably the fastest way to handle it. Layout your positions on sheet styrene using a compass and ruler. The compass will step off even spacing and mark your holes as well. Take the hole punch and position it within the layout mark and punch away. Can get it done in less time than it would take for me to find the right bit in the garage. |
28mmMan | 16 Jan 2011 9:09 a.m. PST |
Good call Scout, all my standard bits are brad points picture I took it for granted :( |
28mmMan | 16 Jan 2011 9:14 a.m. PST |
Actually Dan or any others interested
the way that strikes me as the best way to achieve this process for a larger project would be to make a simple mold and cast in plaster or hydrostone. I have all the materials at hand so it seems a simple choice, but even so
Could be a fun project to consider. |
ScoutII | 16 Jan 2011 9:41 a.m. PST |
I would need to want a whole lot of things before I consider casting. The added cost and time in making molds compared to the time and cost of just making them straight away
If it was a commercial endeavor
possibly (though you can drill a whole lot of holes pretty fast on a drill press with a jig and stacks of 20-50 sheets of styrene). Prep and clean up alone would likely be more time than doing a dozen or more by hand. If you had a bunch of them to do – you could make a template on your computer and print it out. Use some spray tack glue to attach the paper to your styrene and punch away. Save you a minute or two on each one for layout. After that – a simple alignment and positioning jig for attaching the flange (not sure if that is an essential part of the concept or if it is mostly the holes we are after
). |
28mmMan | 16 Jan 2011 10:28 a.m. PST |
That would be viable also :) That is one of the fun aspects of dealing with other people with different backgrounds. I have been making molds since the early '80s and find it easy. But your points are valid. But you will find that jigs are a learned process that does not come freely to those unfamiliar. All in good thought to be sure. And I was thinking of commercial or at least mass production. Not just for this one beam but for related pieces. Fun stuff :) PS For just cutting holes in plastic I like your plan of mass cutting with jigs
smarter not harder :) |
Bishop Odo | 16 Jan 2011 12:45 p.m. PST |
Jigs are the way to go. Jigs and tool making take a certain mindset to create, but there are examples in woodworking videos, the Yankee workshop and U tube, books and magazines, it is an investment in time, but once you see something that will work, you go, "Why didn't I think of that" At my local hobby shop they own a ‘Hot foam knife Factory," it was a brand name with a wire temp control and all the bells and options, for building terrain, but the owners or staff where complaining that they could not cut a straight line. I showed them how to make a fence, like a table saw, and they where kind of ed off at me. It was the, "why didn't I think of that syndrome", it so simple. |
ScoutII | 16 Jan 2011 2:18 p.m. PST |
"Why didn't I think of that" Yah – you get that a lot. Many people who do production for a living (especially in niche fields) really have no clue how to do production for a living. They have an idea – and they figure out one technique
and then they stop. Often times working much harder than they need to. And I was thinking of commercial or at least mass production.Not just for this one beam but for related pieces. Yah – I tend to assume that unless they say otherwise – they are probably talking about a one off project. Nowadays there are a lot of different methods available for the home user. It sort of depends on what they actually wanted to do and what skills they had (and tools they had available). I have done molds for really intricate items that I only wanted a half dozen or so of
and I have also done hundreds of items more or less by hand that were pretty basic. One thing that people really need to keep in mind now is 3D printing too. Not quite to the point where you could print an entire army yet – but something like this, it would only take a few minutes to be designed and you can print them for pretty cheap (depending on the material it can be under $2 USD per cubic centimeter). For terrain and detail parts – it is a great option. |