Paul,
If you or Jeff still have any RX-8 coil
heat sinks on hand, I need one. Just
let me know how much and where
to send the money. Thanks.
Frank


I only made one Frank. Jeff never made any to my knowledge.
Alex Moltena owns it. The demand is not much so far.
Might take awhile for most people to realize it is the best way to go :)

If you know someone with a mill you can get the islands
machined and clamps made. If not my next door neighbor will do it
for $35 an hour. Drop ship the extrusion to me.

The minimum order for the extrusion is enough for two parts as I recall.

Paul Lamar

Would a spreadable thermally conductive compound be beneficial for this
application?  The product in mind is used
between the CPU of a computer and it's heatsink.  If it is of benefit,
would applying it to the stock mounting plate
provide meaningful results?

Product in mind:
http://goo.gl/Bx5Nr

Aaron Buster

That is a given but you still need the islands.
The thing to constantly keep in mind is four cycle piston engines
work the coil half as hard.

Paul Lamar

Found a great heat sink riding the back of the processor in an old HP
computer.  Easy to get to, and free, or nearly so,
when your PC dies.

Lewis.

How big is it. What are the dimensions.

Paul Lamar

Paul,
I have already contacted the supplier. They are no longer
called M&M Metals, instead they are called Alexandria
Industries. Their minimum order is $250 for a six foot
length, enough for about 12 heat sinks. I can't justify
this for only one part; any suggestions?
Frank

Anybody else need some heat sinks?

There are lots of options.
l

<http://www.thermal-solutions.**us/extrusions.html<http://www.thermal-solutions.us/extrusions.html



Check the price from this company on part number
EXT301525



<http://thermocoolcorp.com/wp-**content/uploads/2013/01/**TCP7503.jpg<http://thermocoolcorp.com/wp-content/uploads/2013/01/TCP7503.jpg


TCP7503 will work.


<http://catalog.chtechnology.**com/viewitems/extruded-bonded-**


fin-heat-sinks/extruded-heat-**sinks<http://catalog.chtechnology.com/viewitems/extruded-bonded-fin-heat-sinks/extruded-heat-sinks





All of these will work.

You want something about 3 inches wide with fins 1 to 1.5 inches high.

Paul Lamar

Check out All Electronics:

<http://www.allelectronics.**com/make-a-store/item/HS-176/**


17.25-ALUMINUM-HEATSINK/1.html<http://www.allelectronics.com/make-a-store/item/HS-176/17.25-ALUMINUM-HEATSINK/1.html

**


Jim R

That is a very good price. You can cut and inch off the width with a
band saw or hack saw. That might be enough for three.

Paul Lamar

For $250 just for heat sinks, I start scrooging the electronic junk
places, try Digi Key catalog, maybe even put a fan on it. Not using heat
sink grease is like pouring cooking oil into your engine.The islands are
just to stop the coils moving around?? You need a flat surface for max.
heat transfer, that is where the grease come in.
Tony


Paulo, Don't forget about E-bay,  I bought some  3" X 7" X 2"  finned
heat sink extrusions for $7 each plus $8.45
shipping  to convert an AC welder to DC and some 300 amp 1200 v  diodes
for $1.70 each .  I just looked under heat
sink and there were 47,246 hits. items  250672045065for $3.99  solid
state relay mounts look interesting  or item
271161273217 for blocks of extrusion 7-1/2" X 13 X 1-3/8" for $13.A
narrower search for large aluminum heat
sinks got 38 hits

george grimes

The All Electronics heat sinks have a few holes in them but nothing that
would affect our use. The fin density is high so they are rather heavy
at about 1.6 pounds each for four coils. Lots of fins means good cooling.

Paul Lamar



Milo,
I'm sorry to have taken so long to respond on your
offer to buy the metal for the heat-sinks; but, it's
not the money that concerns me. It is more about
spending that amount of money for only one or two
unit's. Now, if we could get at least eight or more
commitments for these units, then I will order the
material and have them fabricated here and then
ship to each person. Thanks.
Frank


Mill a prototype Frank, and loan it to me for inspection and I will put a
free ad on the web site for you. You can get two out of a $25 All
Electronic surplus version. Each heat sink will then cost $12.50 before
machining.


Paul Lamar

Just an idea of an alternative to the extrusions:

A five foot length of 6061 1 x 3.5 inch flat bar is 80.00. The cooling
fins can be cut on a regular table saw to desired configuration. Set the
fence and depth of blade on a piece of scrap lumber. Run the aluminum
through slowly in a similar fashion to ripping a piece of wood. Keep feed
rate slow to keep the heat down on your blade. Aluminum cuts easily with
wood blades as long as they are of good quality, sharp, and you go slow.

Alan Mullen

Good idea Alan. Good trade off of money for time.
The All Electronics sinks have about 5 or 10 fins per inch.

Carbide blades work well with aluminum.



Paul Lamar

Paul,  Carbide blades cut the aluminum in it's non hardened state as long
as you keep it from galling onto the blade.

I was plant engineer for Easco aluminum
(extrusion presses) for a while and
we used 20" carbide blade saws to cut to length. We lubricated the saws
with a stick  of bees wax by  touching it in the running blade about
every 3 cuts.

Saws were an Oliver

air feed. The blades were resharpened once a week. In places like a
milling

machine where it can be contained a mist of kerocene and air worked on tool

steel cutters and drill bits.

george Grimes

Contained is a good term to use here.  Be sure to buy and use the
appropriate personal protective equipment while you saw your way through
the aluminum plate.  You don't want to breath the aluminum dust, take
any chips in the eye, or ruin your hearing.  You may not want to get the
aluminum shavings into your table saw motor either.


Mark LaPierre