Paul

 I've been thinking about building a 3 rotor P-port, and some of the
 sealing
 techniques used around the
 intake tube. I know you have suggested epoxys in the past but what
 about using
 lead or tin?
 fairly easy to melt and will easily handle the heat. My thought was
 to clamp a
 steel plate to one side of the rotor housing
 fill the water jacket up with lead or tin then mill the hole in the
 rotor
 housing for the P-port. Has anyone suggested that yet?
 I think body shops have been doing that for years to fix panels on
 cars.

 Tony

 It is worth a try. I think it will cool when you pour it into
 the water jackets and not bond. However heating the rotor housing
 to 1100 F in an oven and then poring the liquid brazing
 stuff might work. You will have to clean out the water jacket
 with a die grinder to get rid of the oxide and coolant deposits.

 We don't mess with any of that in the welded p-port version.

 Paul Lamar

 We finally have a reliable system that works and easily repaired after
 a couple of years of trial and error AKA R&D :)

 We don't really use epoxy anymore. We tig weld a SS tube to
 the steel rotor liner. Pin hole leaks are sealed with liquid
 silicone rubber.

 http://www.rotaryeng.net/Welded-steel-p-port.html

 We also have a youtube video or two on the subject.
 See the attached pdf for a list.

 There is no reason for the tin or lead to bond to the aluminum
 so you would probably wind up with leaks.

 Paul Lamar


 There are alloys used to sweat dissimilar metals together, along with
 fluxes to clear oxides from the surfaces. Temps range between 350 to
 1200f depending on metal types to be joined. --
 http://www.muggyweld.com/index2.html


 I am going to try this method when I do my P ports, both with the
 stainless tube, and aluminum tube. A benefit may be eliminating any
 silicone sealants required.

 Although I can tig the stainless tube to the housing myself, I am not
 certain it will be successful after the hard chrome gets melted and
 mixed with the stainless on the liner, as I am not sure what the
outcome
 has been with this phase of the project.

 Ed Carver


 Mark Steitle has been flying for awhile with welded p-ports.

 We have 4,400 hits around the world  for almost a year
 and no nay sayers yet :)

 http://www.youtube.com/watch?v=NKJ00JsnS8A

 Hard to guess how many have been built.

 We only resort to the silicone if you find a leak
 after the engine is assembled. It is rather
 easy to check for leakage if you do this.

 I have probably close to several hundred hours fooling
 around trying to bond in p-ports. One engine developed leaks
 after it ran and I had to drive half way to Denver to pick it up,
 take it home, disassemble it and start over.

 It can be done if you do everything exactly right and use just the
 right procedures and materials. Aluminum is hard to bond to
 as it develops an oxide coating that epoxy does not stick to
 rather quickly when exposed to air. We discovered this
 back in the 1960's when we tried to build bonded aluminum
 monocoque race car chassis's at Chaparral.

 Here is an eye opening little test.

 Take four small strips of aluminum. Bond two to together with
 epoxy. Treat the next two with an aluminum prep kit and
 bond them together. Now try to bend them both after cure.

 Paul Lamar


 Paul
 Thats certainly one way of doing it, The nice thing about using the
 HTS-2000 rod
 is there is no welding
 you would be drilling a hole in essentialy a solid block of aluminum
 straight
 thru to the rotor housing
 that's it no grinding cleanup nothing, if done correctly no leaks
 either. You
 should realy watch the videos on their website it's pretty
 impressive stuff.

 http://www.aluminumrepair.com/index.asp

 Tony

 As I said above it won't bond to the aluminum in the rotor
 housing unless you get rid of the oxide first and then by heating
 the rotor housing to 1100 F. If you don't do that as the mixture
 cools it will shrink moving away from the inner and outer walls
 in the rotor housing water jacket.
 Furthermore you could destroy the existing heat treat on the
 rotor housing. Try the tig welding trick. You will like it as
 it only takes 5 minutes. It does not distort the aluminum housing.

 The video has nothing to do with what you are suggesting.
 Notice they are heating what they are bonding parts to.
 Notice also that they are filing the old part to remove
 the aluminum oxide coating. You will have to go into
 the water jacket and grind out the entire interior
 surface with a burr inserted into a die grinder.

 Also good luck finding a low cost oven large
 enough to heat the entire rotor housing to at least 500 F
 and maybe 1100 F.

 However you are welcome to try it if you wish.
 Make sure you build up the p-port engine and run it
 full power as we have. Pressurize the cooling system to
 50 psi to be certain there are no leaks.

 If it fails make sure you let us know :) I always let
 people know when something I try does not work no matter
 how embarrassing. We learn more from what does not work
 than we do from what does work. Document each step, as
 we have, by taking a lot of pictures.


 Paul Lamar

Paul,

I filled the water jackets around the p-ports with Ultra-Grey RTV.
Bonded to the aluminum just fine and stuck like glue.  It didn't leak
either.

Mark

For the new people Mark is using the SS tubes welded to the steel
rotor housing liner.

Silicone sticks to anything as far as I can tell. It even sticks
to glass. The beauty is it is flexible so it can expand and contract
unlike epoxy to follow the shape of the water jacket as it heats
up and cools off. I take it you are still using the O-rings inside
the sealing blocks.

Just silicone alone might work. Would be an interesting experiment.
Be great if you could get it in liquid form. No worries then about
voids. Easy to remove and start over. Epoxy is a pain to grind out
and start over. Ask me how I know :)

Paul Lamar

Paul,

I have the early sealing blocks before the O-ring sealing blocks were
invented, so no, they are sealed by 1) welding the tubes to the liners,
2) Ultra-grey under the sealing blocks and in the cavities, and 3)
o-rings under the bolt heads (chamfered the holes in the sealing blocks
for the o-rings).  It took me a few tries to get all the leaks stopped,
but once I got them stopped, they haven't leaked since.

Mark