bug stage I made

[johan]

A rather bad photo of a vaguely ok thing I made, which will hopefully be a reasonable improvement on the somewhat limiting "insect examination stage" that I currently use. Made from a maritime candle holder cut into bits and spraypainted black (to cut reflections)



The idea is I can rotate my thing's arms and its base as much as I like but the actual focus point where the bug is won't change (it's the centre of the circles, ie the end of the pin in this photo). The bug will be on a pin that's on a kinetix magnetic thing with putty inside it so I can just slide the pin in easily. The kinetix magnetic thing itself attaches to 4 mini magnets that I put into the innermost arm. This magnet <=> magnet mechanism allows me to both rotate the kinetix magnetic thing itself but also put it on a different magnet point if the arms get in the way of lens or diffuser. It's not completely finished yet as I'm replacing this base with a clear plexi one (to be able to use light from underneath) but almost there.

Bottom line hopefully this'll let me mount a bug and then readjust its position/angle as much as I like without endless refocusing or repositioning. The arms rotate easily, I did initially want to have handles on the end but I couldn't find the right bits easily.

I used meccano nuts and bolts, nylon washers and araldite. It's quite neat when combined with the other 'thing' I made in the last couple of weeks whilst waiting for my stackshot to come back from the stackshot doctor, a combo doubled microscope base ( ie with extra up/down mover track) with transparent focus stage (to be able to light from underneath) and mechanical stage giving x,y and z

[g4lab]

Very cool thing.

When you took the original gadget apart, do the rings hold together without both bearings or did you have to redesign the bearings?

[johan]

Very cool thing.

When you took the original gadget apart, do the rings hold together without both bearings or did you have to redesign the bearings?

Well in fact the original has double the number of screws/bearings, and they're of a type that means 1 on either ring doesn't hold it together. So I drilled new holes and put in different nuts, bolts and washers. Which fyi all come out of meccano sets - buying a £5 meccano box in a charity shop gets you hundreds of nuts and bolts for little projects like this

[canonian]

Hi Johan, I admire your DIY skills, great piece of hardware.

[ChrisR]

To my shame this thing is still in a box.

I've often mused that gizmos like this could be mass produced from slices cut from plastic plumbing pipe, and pipe clamps. It/they come(s) in black, at about eg 22, 32, 40, 50, 63, 75, 100mm. Or copper of course.
You could adjust the pin length/rotation with some screw parts from a Wittner pattern violin sting adjuster, glued to a ring magnet - or washer.
I should have one some where but they're easy to find on the net. They do horrible things to the sound from a violin, but ...

The a-ha bit is the "bush" in the middle. You knew that.
Two nuts could be used on the bush either side of a plate, magnet, ping pong ball etc..
A piece of bush could be screwed onto the sharp end of the brass adjuster with its other end filled with blu-tack, to hold a specimen pin. Yes?
This gives a pin-mount, with rotational and longitudinal adjustment.



Blu-tac's not the best, perhaps some canada balsam mix or ancient lanolin goo would be better.
The screws stiffness can be adjusted by squeezing and tightening the screwdriver slot.
I couldn't find an insect pin, and the other piece of ball would be better - but hard to see into for this. Johan's mount is better.
This is I think a " 3/4" violin string adjuster, they come in a couple of sizes.

Edit - cm & mm squared paper.

[elf]

Have you had a chance to use this yet? How well is it working?

[johan]

Have you had a chance to use this yet? How well is it working?

I havn't had a chance to do a stack yet (hopefully this w/e) but it looks to me that it very much works. I've finished it off by replacing the metal stand/base with a 10cm diameter round plexi sheet 1cm thick, which has a stud sticking out the bottom, at the centre of rotation.

This goes into a hole on the redone x/z microscope slide stage (which itself now has plexi 20x15 cm on it so it's actually a stage with x and z axis movement) - and when I put the device in the hole, I just rotate it on its axis. It's very nifty now, every axis of movement and rotation I could possibly want.

The last stage for this project is to construct the chilling chamber that I'll use it in conjunction with (replacing the magnetic ent pin mount with a magnetic croc clip mount to be able to do (cold) live moths on twigs/leaves/whatevers, but I expect this to take me most of the winter. But at least I can do dead properly now.