Carbon Fiber Spider

[wimvb]

The difference between thin and thick vanes is most visible int the way colours are diffracted. Also, thick vanes block more light than thin vanes.

[Robert72]

On 23/06/2021 at 23:30, wimvb said:

The difference between thin and thick vanes is most visible int the way colours are diffracted. Also, thick vanes block more light than thin vanes.

I didn't mean the difference between thin and thick vanes, I meant the gap between the vanes. If I read your previous post correctly the gap between the vanes is the thickness of the thick vane. The gap between vanes on my initial design was 10mm. Does  that even matter? I think someone in a previous post mentioned if the gap is small it has a larger effect.

Regardless, I'm going to have a crack at a single vane design.

[wimvb]

I'll see if I can dig up the configiration image that Maskulator used to calculate the diffraction patterns. But the thick vanes that I used were considerably thicker than 10 mm, and so was therefore the spacing between the double vanes.

 

Addendum:

I added the configuration images to my earlier post with the diffraction patterns.

Edited June 25, 2021 by wimvb

[Robert72]

Here is the single vane equivalent, it's basically the same however the central box has been replaced with a 40mm tube. The tube and vanes are semi-slotted and bonded. Not sure about the ends, how important are they in terms of diffraction? If need be they can be integrated into the tube, this would give a very clean light path.

[wimvb]

On 23/06/2021 at 17:36, Robert72 said:

Maskulator seems like a handy app. The double vane spacing seems quite small though (I don't know if it makes much difference).

I edited my earlier post and inserted the configuation images for the diffraction calculations. As you can see, I exaggerated the thick spider and the distance of the double thin spiders.

[Robert72]

Now let's make a kit of carbon parts....

I've also made a rudimentary building jig. The outer ring and vanes are held by the adjustable quadrants of MDF. The inner ring is held by the steel dowel. Should be good for holding all the parts in position while bonding.....

[Robert72]

Here's a trial fit in the building jig....

 

 

[JamesF]

Are you sure it's not really woven liquorice?

James

[Robert72]

OK, so the sub assemblies are pretty much done....

A close up of the spider hub.....

The adjuster plate with brass inserts and anodised bolts. I chose red to stand out under red lighting. There is a bigHead female bonded onto the back there to act as a kind of lock nut to resist rotation....

Side view of adjuster plate and bonded bigHead.......

Assembled. Still awaiting compression spring.......

Internal view of the angle thingy. This is where the spring will go. The bigHead makes an ideal spring rod, but i think i will need a bigger washer......

Candle holders make ideal spider stands........

[DuncanC]

Looks good! how did you bond the parts together? Epoxy resin?