Yes, socket*less* cap screws. As in no hole to insert a hex key, but other wise the same shape and height as the head on a socket head cap screw. Roughly 5/16" to 3/8" X short, standard or metric, course or fine thread, grade, material unimportant. Does have to be metal... Thought about ordering shoulder bolts and cutting the head off. May end up going this route but looking for a less expensive and labor intensive solution since I may need as many as 50.
Could possibly live with an acorn head if it lacked wrench flats, but prefer the cylindrical over bullet shape.
Breakaway Nut/Non-Removable Security Nut Aluminum Hex nut breaks away when nut is tightened leaving only the tamper-resistant conical portion. No special tool is required - uses standard wrench for installation.
or these:
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Carriage Bolts have round heads with square necks under the head to prevent the bolt from spinning as the nut is applied. Also offered with ribbed neck.
Looks tall enough. Not crazy about the conical shape but could live with it if it works... Argh, have to ask for a quote.
Not tall enough. Hard to explain exactly what I'm trying to do but it needs to be tall enough to leave a 'bump' on the inside of a thick walled plastic part so sand can stick.
Another poster mentioned breakaway nuts but you can get bolts in this style also. I used a couple for a job years ago but can't remember what or why now. The bolts were used to hold the ignition barrel and steering column lock on a European Ford application and were IIRC 8mm and maybe
30mm long but it was a while ago. Got them from stock at the local Ford dealer parts department so a good place to start as I would guess the same might be used in the US as well if that's where you are.
Y'know, I've seen such breakaway bolts in a locksmithing catalog (which I can't put my hands on now). You might check with a local locksmith for some advice.
Also, without knowing exactly what it is you're trying to do or how many you need, I'll just take a shot: Would it be possible to just take some cap screws and fill in the sockets with solder? Shouldn't be a big deal at all, unless you need thousands.
Actually did almost that a few years ago. Only needed four total for that application since it was to control shrinkage in one particular area of the finished part. Used TIG and then smoothed and rounded the weld as I was removing the knurl and putting a degree or two of taper. No longer have ready access to TIG or oxy-acetylene, doubt stick or flux core would work very well. Plus I may need as many as 50.
What I am trying to this time is add places for sand to pause long enough to stick to the hot plastic. Rotational molding uses powered plastic rather than the pellets used in injection (and blow) molding. Normally no sand is used, but since I'm making bat house shells and want the inside wall to be rough like a cave wall... Since sand does not melt it tumbles around until the very last before sticking.
Works great in corners, narrow areas and around bumps or projections. However, large flat areas of the mold do not allow time for the sand to stick since the mold is constantly turning.
A bit more back ground and a few pictures near the bottom of this page if anyone is interested.
Have seen small electronics style standoffs in round. Never seen larger ones in anything other than hex. Will do a bit of searching...
Ouch! They start at $10 each for too small.
See my reply to rangerssuck above.
Interesting! This makes the third or forth suggestion of something I had no idea even existed. Doubt they would be tight enough to not stay in the first part molded.
Be great if I could find some cheep enough. Trivial to sand the knurl off.
Why not plain hex heads? I don't see where they need to be perfectly round; the sand thickness may be uneven but who's to say what the bats will prefer? :-) Oh, also look at 12-point head bolts, not round but rounder than hex heads and no hole.
Actually did almost that a few years ago. Only needed four total for that application since it was to control shrinkage in one particular area of the finished part. Used TIG and then smoothed and rounded the weld as I was removing the knurl and putting a degree or two of taper. No longer have ready access to TIG or oxy-acetylene, doubt stick or flux core would work very well. Plus I may need as many as 50.
What I am trying to this time is add places for sand to pause long enough to stick to the hot plastic. Rotational molding uses powered plastic rather than the pellets used in injection (and blow) molding. Normally no sand is used, but since I'm making bat house shells and want the inside wall to be rough like a cave wall... Since sand does not melt it tumbles around until the very last before sticking.
Works great in corners, narrow areas and around bumps or projections. However, large flat areas of the mold do not allow time for the sand to stick since the mold is constantly turning.
A bit more back ground and a few pictures near the bottom of this page if anyone is interested.
Will look for 12 point heads since I vaguely remember seeing them in a taller high head version. Bats as you have noted would not care if I electro formed turds and bolted them to the mold. Pesky humans however (ones with money) want things that look beautiful and have no obvious "I know how they did that" features.
And yes, most of us on this newsgroup are not typical and spot 'how they done that's' frequently. I know I do...
Not sure what size head you need, but can you mold in a rubber bumper with threaded stud on the backside? Something like
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or browse their other products and maybe something will click.
Will look for 12 point heads since I vaguely remember seeing them in a taller high head version. Bats as you have noted would not care if I electro formed turds and bolted them to the mold. Pesky humans however (ones with money) want things that look beautiful and have no obvious "I know how they did that" features.
And yes, most of us on this newsgroup are not typical and spot 'how they done that's' frequently. I know I do...
What about just chucking up hex headed bolts in your lathe and turning the head to be round? No lathe, then clamp a bit to the drill press table and use your drill press as a lathe.
Or, if a drill press but no lathe bits, use a file. No drill press, clamp a drill motor in a vise, and use a file.
Real hex-head cap screws are going to be a little hard, but a file will do it on those small screws. If they're ordinary hardware-store screws, they'll file easily.
If you can thread the hole it goes into you could thread some rod, stop and leave part unthreaded (the 'head'), screw it until the unthreaded portion jams to hold it in place.
One more thing: If you're going to chuck the threaded end of a screw in a drill (or lathe) chuck, wrap wire around the threads to protect them. Ordinary copper or steel wire will do.
Ah, and the ones that come with many toggle clamps are even closer to size and shape I'm looking for. Rubber however would not last long and if Teflon or some other high temp plastic was used it would leave a hole all the way through the part. Teflon is often used as an insulator to keep an area that will be cut away from forming. On a large part it can save several pounds off the shot weight. Save big buck$ over time...
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