My Trumpeter "Seawolf" Conversion

[petn7]

I don't know if you

I don't know if you did it, or if it matters, but I lightly oiled both sides of right where the seal rides on the rod. I figured it could not hurt.
Mike's Subworks also sells pushrod seals. That is what I used on my RCAB cylinder.
I have not tested it yet. I discovered dropping my wtc on the ground packing for the regatta had done servo damage and a few other things, so I am redoing my cylinder now.
Fortunately, everything will be fine.

I did have both servo pushrod and seals lubed with silicone grease. Do the BHS pushrod seals from Mike's Subworks use o-rings?

[bigdave]

No, cup seals. BD.

No, cup seals. BD.

[petn7]

Alright, so I did more

Alright, so I did more underwater testing and the other pushrod seal leaked when the vacuum was created. I'm beginning to think these 1/16" pushrod seals were not designed for RCABS use, or at least require slightly thicker 1/16" pushrods. I doubt this is the case, since these seals were very "stiff" and when new, I could feel resistance when inserting the 1/16" stainless steel pushrod. Or maybe these are slightly too thick and therefore compress the o-ring so they can no longer hold an RCABS vacuum?

Any reason why the 1/8" BHS seals hold the RCABS vacuum, but these 1/16" seals are having trouble? It should be noted these seals were installed and sat with 1/16" pushrods for several months. I imagine submarine seals should be able to deal with that type of treatment.

I might have to order some 1/8" BHS pushrod seals...

[petn7]

The BHS seals have been

The BHS seals have been ordered from Mike's Subworks.

Cup seals > o-ring seals with RCABS.

Don't use Caswell o-ring seals for RCABS. They should be more than adequate with RCABS-R or gas/snort systems, though.

[wayne frey]

Just to be clear, my

Just to be clear, my system is the reverse RCAB, which does not cause significant pressure changes within the WTC. So, anybodys seals SHOULD work with my system.
For the regular RCAB system, I am not sure. I just like the idea of the reverse RCAB being contained, as it were, and not doing anything to the rest of the WTC as far as pressure changes

[petn7]

Just to be clear, my

Just to be clear, my system is the reverse RCAB, which does not cause significant pressure changes within the WTC. So, anybodys seals SHOULD work with my system.
For the regular RCAB system, I am not sure. I just like the idea of the reverse RCAB being contained, as it were, and not doing anything to the rest of the WTC as far as pressure changes

I'm with you, but I don't have the room for a pressure vessel on my "Seawolf."

Maybe my next project...

[Guest]

Try quality bellow seals like

Try quality bellow seals like the ones from Robbe or MHZ ,they can take tremenduse pressure. I use no other type since all other ones ultimatly failed in one way oranother,or cause exsesive friction on the servos.

[Guest]

Bellow seals with RCABS

The bellows seals I have tested with RCABS are not reliable because they unintentionally cause the attached pushrods to all controls to move when you inflate the bladder. The partial vacuum in the WTC collapses the bellows attached to the pushrods. SubTech BHS-1 cup seals seem to work best. When you inflate the bladder, the BHS's efficiency actually increases. I don't have info however on the smaller diameter pushrod seals, just the ones for 1/8" diameter rods.

[petn7]

Re: Bellow seals with RCABS

The bellows seals I have tested with RCABS are not reliable because they unintentionally cause the attached pushrods to all controls to move when you inflate the bladder. The partial vacuum in the WTC collapses the bellows attached to the pushrods. SubTech BHS-1 cup seals seem to work best. When you inflate the bladder, the BHS's efficiency actually increases. I don't have info however on the smaller diameter pushrod seals, just the ones for 1/8" diameter rods.

I do, and they don't work. They'll work until the o-rings stretch out. I presume the BHS seals don't suffer from this problem.

[petn7]

I just tested the new

I just tested the new pushrod seals (BHS from Mike's Subworks) and they are perfect!

I created the full vacuum and forced the WTC to the bottom of my test basin. The main shaft and 1/8" BHS pushrod seals were under about 4 inches of water (under the vacuum) and there were no leaks after 15 min. This is a huge improvement over the 1/16" seals which couldn't hold the seal under vacuum for even a few minutes and under less than 1 inch of water.

All I need now is to wait for my lead-free weights to arrive, add foam, and this sucker is done.

I'll be posting some more pictures soon.

[petn7]

Here are some pictures of

Here are some pictures of the completed WTC with RCABS ballast system :

[anonymous]

Nice and clean. I traditionally

Nice and clean. I traditionally go for the bowl of spaghetti look in my WTCs...

[petn7]

Nice and clean? It is

Nice and clean? It is a "bowl of spaghetti" in my WTC...at least in the front section.

[redboat219]

Got any pics or video

Got any pics or video of your Seafox in the water.

[xxl]

looks good

looks good