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-   Rotary Engine Building, Porting & Swaps (https://www.nopistons.com/rotary-engine-building-porting-swaps-55/)
-   -   My First Port (https://www.nopistons.com/rotary-engine-building-porting-swaps-55/my-first-port-38274/)

FD3S_wanted 05-03-2004 11:02 PM

This is my first port on a TII housing. It's mild, I followed the RB template to start. I'm praticing on this housing before doing a port job on my 13B-RE housings.



http://www-edu.gel.usherbrooke.ca/co...port_TII_2.jpg



http://www-edu.gel.usherbrooke.ca/co...port_TII_5.jpg



I would like to know what do you think ? What should I improve ? I have pic of the runner but the quality is poor. How far could I go to the opening side so that the corner seal can't fall ?



Thanks for your help!



Alex

BDC 05-03-2004 11:37 PM

Not bad, alex. Hit the port tunnel up and sand the walls down to medium-grit finish and also don't forget to scissor the short radius (the iron where the corner seal and apex seal ride along near the inner water jacket o-ring land ..



B

SomeGuy_sg 05-04-2004 06:16 AM

BDC; what do you mean by "scissor the short radius "

Lynn E. Hanover 05-04-2004 07:39 AM


Originally Posted by SomeGuy_sg' date='May 4 2004, 03:16 AM
BDC; what do you mean by "scissor the short radius "

Typical of the port job layout is to draw a line along the edge of the rotor to determine the new closing line. This results in the unsupported, trailing end of the side seal arriving at the closing line at once.



By slightly increasing the closing line radius at the outer end of the closing line, you can have the side seal return to the flat of the iron from the inner end, with the very end arriving last. This gives a very gentle return to the flat and there is no bounce, and no rounding of the very corner of the end of the side seal. Port timing is not changed. The bowl of the port need not be enlarged. You should radius and polish the closing line anyway. So just make the outer end of the closing line have a larger radius than the inner end.



So, the side seal crosses the closing line just like the blades of a scissors. Or just have the inner end of the seal closing the port before the outer end.



Lynn E. Hanover

Lynn E. Hanover 05-04-2004 08:03 AM

1 Attachment(s)

Originally Posted by Lynn E. Hanover' date='May 4 2004, 04:39 AM
Typical of the port job layout is to draw a line along the edge of the rotor to determine the new closing line. This results in the unsupported, trailing end of the side seal arriving at the closing line at once.



By slightly increasing the closing line radius at the outer end of the closing line, you can have the side seal return to the flat of the iron from the inner end, with the very end arriving last. This gives a very gentle return to the flat and there is no bounce, and no rounding of the very corner of the end of the side seal. Port timing is not changed. The bowl of the port need not be enlarged. You should radius and polish the closing line anyway. So just make the outer end of the closing line have a larger radius than the inner end.



So, the side seal crosses the closing line just like the blades of a scissors. Or just have the inner end of the seal closing the port before the outer end.



Lynn E. Hanover

There is no need to move the bowl shape of the port. Just increase the radius and polish job a bit more on the outer end of the closing line than the inner end.



The red line is the side seal as it crosses the closing line. Notice how the lines cross like the blades of a scissors.



I would break all sharp edges around the port with 400 silicone carbide paper and solvent. No sharp edges should be left once the port job is finished.



Lynn E. Hanover

FD3S_wanted 05-05-2004 12:03 PM

Thanks for comments guy, I will improve it.



I understand the radius thing. But what I don't understant is this:




Hit the port tunnel up and sand the walls down to medium-grit finish


Sorry I guess it's easy to understand it's maybe just because english is not my first language. https://www.nopistons.com/forums/pub...1047683561.gif BDC do you mean to sand the top of the runner or the top of the port ? Is it just to cut some rough ?



Thanks!

RETed 05-05-2004 03:09 PM

Good work!





-Ted

knonfs 05-05-2004 06:26 PM


Originally Posted by FD3S_wanted' date='May 5 2004, 01:03 PM
Thanks for comments guy, I will improve it.



I understand the radius thing. But what I don't understant is this:







Sorry I guess it's easy to understand it's maybe just because english is not my first language. https://www.nopistons.com/forums/pub...1047683561.gif BDC do you mean to sand the top of the runner or the top of the port ? Is it just to cut some rough ?



Thanks!

I don't get it either https://www.nopistons.com/forums/pub...1047683561.gif https://www.nopistons.com/forums/pub...1047683358.gif https://www.nopistons.com/forums/pub...1047683664.gif

GMON 05-05-2004 09:18 PM

I assume that he means becuse you increased the size of the port on the top that you should do the same to the port runner.



https://www.nopistons.com/forums/pub...1047683561.gif

kahren 05-06-2004 07:03 PM

make the 90 degree turn of the port a nice smooth transition, as well as what LYnn said


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