Here are a couple of pics of the EJF Viofan adapter to convert the older gas Viofan to electric. I'm not sure it is supposed to have this much play in it, but I've been in touch with Robert from EJF and he is going to let me know.

Ok I just finished writing this one because I was sick and tired of waiting 1000+ seconds for the "cone" program to start up since I'm too cheap to pay for it.

Anyway this spreadsheet isn't as cool as the cone program, but it gives you the info you need to roll your own. All you need to input is the outside diameter of your fan, the diameter of your tailpipe, and the length of your tailpipe. NOTE: ALL DIMENSIONS SHOULD BE IN millimeters. The spreadsheet will work if you use inches or feet for that matter, but since most people use mm as the units of measure for EDF I figured I would stick with convention. But as long as all units are the same then the sheet works fine. Oh yeah, input in the blue fields in the upper left. Results are in the yellow fields.

Enjoy


Edit: I found an error in the formula. DOH Sorry about that to the 7 people that bothered to download the original spreadsheet. It's fixed now and has been verified.

Here is a simple Excel spreadsheet that calculates FSA of a ducted fan. I see people ask how to calculate FSA a lot. This spreadsheet will give you 100% FSA down to 70% FSA in 5% increments. Only input the diameters of the fan shroud and the fan hub (green cells). The fan hub diameter should be the largest diameter of the hub as some fans have a pointed tip.

I have updated this spreadsheet. It now also calculates exhaust diameter at different percentages of FSA from 100% down to 70% in 5% steps. This is done for both a single exhaust outlet and a bifurcated (two outlets from one fan) exhaust.

Somehow I deleted this spreadsheet a while back. Sorry about that.

In response to all of the "yeah but they had to make the intake larger so it would fly better" and the "you wont even be able to see how ugly it looks when it's flying" people. I give you your new "Sabre".

Here is a screen shot of the cnc wire cutter that I'm building. It's drawn in Google Sketchup and based on a design by Blueswede from the yahoo cncfoamcutters group. It uses drawer slides and acme threaded rod and is all out of MDF.

I'm slowely building this thing (heavy emphasis on slowly). Really if I had a free weekend I could knock out the MDF on the table saw, it's just getting a free weekend that's tough with 3 sons.

Steve