Paul wrote:
We are about to go into mass production with this aluminum bell mouth.
Fits 2 inch OD tubes with .0625 wall. Can be epoxied on or tig
tack welded. No price yet. We are still looking for a distributor.

Paul Lamar

Mark wrote:
What are the design critia for bell mouths. I assume any radius helps, but there seems to be a wide range of shapes out there from  little circular radius bellmouths like these to larger more
gradual and epilliptical ones. When I made a set for Brian Trubee, I just took the dimensions he wanted and modified from circular to elliptical because it seemed more logical from an airflow
perspective. It was a fun project, but way too much work on a little 7X chinese lathe CNC conversion. Made heaps of swarf :)

http://www.wrathall.com/Images/Bellmouth.jpg

I would guess this topic much have been explored at great depth by the racing community. May be Archie has a definative word for us?

Regards,
Mark

Those are beautiful Mark. How much money do you charge?

Do they fit 2 inch OD .065 wall tubing?

How does one fasten them to the tube?

Paul Lamar

Their were two with 42mm ID and two with 47mm ID. There is a step to slip over the tube OD, and they could be bonded, but I think Brian welded them (Right brian?)

Sorry Paul, This was the first complex shape I had done on my lathe, and it showed me that that the lathe is just too small for it. The spindle only has 250w, so to core out 47mm you end up doing a
couple of hundered cuts with the boring bar.

I would estimate I put 200 hours in to get the four bell mouths for Brian. I really don't want to do any more. On a real CNC lathe, this would be a very simple quick part (although not very
efficient - you should really start with a casting).

Mark

 
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