found a source for steel disc - would 1/4" be thick enough?

[sunbelt57]

http://www.ebay.com/itm/1-8-125-STEEL-PLATE-12-DIAMETER-DISC-CIRCLE-/320594034708?pt=LH_DefaultDomain_0&hash=item4aa4e4c014

[OperaHouse]

WOW.......Just goes to show you can sell anything on ebay. 

[Bluevitz-RS]

Use old table saw blades. 

[fabricator]

1/4 would be thick enough but those are 1/8.

[sunbelt57]

1/8" right. I don't suppose you could weld 2 together. Naw, that would be a cludge. Now, what did I do with those old saw blades...

[sunbelt57]

http://store.otherpower.com/parts/set-of-2-steel-magnet-rotor-disks-for-10ft-wind-turbine.html

OK, I'm looking at the description of these discs and it says:

These are 12" outer diameter. They have a 2.75" diameter hole in the middle. Both have 4 holes, 5.010" in diameter located on a 4" diameter circle (this is a common bolt pattern for car, and trailer hubs)...

What is the 5.010" mean? That can't be the distance between adjacent bolt holes. Is it a typo?

[klsmurf]

I'd say typo, as you typically use 1/2" stainless all-thread.

[sunbelt57]

He just emailed me and said it was a typo. Its supposed to be 0.51"

[fabricator]

It's pretty hard to keep 1/8 discs flat, you need flat so you can have a reasonably tight air gap, don't even think about old saw blades, they are a nightmare, they are hardened so you have to anneal them to drill holes in em or cut holes with a plasma cutter. And if you have to do any welding on them they warp like crazy, and fab shop can cut you discs with water jet, plasma or laser with all the holes you need usually at a very reasonable cost.

[electrondady1]

their usefulness depends on the scale your building on.
the strength of your mags etc
if it's mild steel they will be a bit floppy and will maybe move a little bit when used for a dual rotor
you could laminate two disks together to stiffen each rotor up.

i have found i can drill saw blades if i use those golden titanium type bits.
but there isn't enough meat to put a thread on the disk so you need to laminate a spacer for the jacking bolts   

[CraigM]

Look at the left hand side of his ad where it says Store Categories and click on Circles/Discs.

This seller as 1/4", 3/8" even 1/2" thickness in various diameters.

Lots of options in 1/4" that will work just fine and they also offers custom orders. (plasma cutting)

Would be interesting to see what they charge to cut holes for trailer hub mounting.

[sunbelt57]

I thought it was a joke when someone first mentioned saw blades. I guess they would work if the mill is small enough. I can buy the ones from otherpower (with the holes already drilled in a 4 bolt/4" pattern to fit most trailer hubs) for the same price as the ones on ebay. Thanks for your help.

[Bluevitz-RS]

yeah I only mentioned saw blades because that link if for .125" 1/8 thickness plates.