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

Keith Moore wrote:

Paul:

I made half inch radius bell mouths in aluminum with a carbide router bit
($35 at Home Depot), and a table mounted router.  The bit mounts a small
bearing at the end to locate the ID of the inlet.

The aluminum cuts easily with light hand control.

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