bertram31.com

Hey Guys...What is the proper material/seal to use where the rudder port flange will meet the hull bottom?? Also, these must be bronze bolts correct, not Stainless?? Thanks, John

Not sure exactly what you're looking for, but have a look at this...

http://bertram31.com/proj/struts/strut_backing.htm

Boat life or 4200 will work.
Bronze bolts are preferred, but stainless will work. Make sure they are tied into the bonding system.

John

Did you make an angled ship to go under the rudder port so the rudders are straight or are you going to let them sit at an angle? I made a wedge. Believe it or not hard.

As an FYI, I went to the Container Store, and found a round tin container that was the exact size of my rudder port flanges. I had a big enough piece of the widest part of the old shim to get the correct angle. The tin needs to sit on a flat level surface then one end needed to be raised 3/8 of an inch. I used the thickest part of the old shim to get there. Then on the inside of the tin, I drew a line on the low side of the tin that was 3/8 inch high. That is the line you will poor too.

I mixed up some slow curing epoxy, and poored the epoxy until it came up to and a hair over that 3/8 inch line. Once it set up I had my shim. Drilled out the center hole and then set it up in the boat and held it until I had the shim and the port lined up so the rudders would be straight. Marked were the bolts would go through, took it apart and drilled out the holes.

I made a few mistakes, so I went through about 6 tins. Luckily they are pretty cheap.

Tony...The rudder ports I took off the boat are still in good shape and were cast with an angled flange to set the rudders straight...The only thing is they are old style, strictly allow for packing and a compression fitting with 2 tightening bolts...I have another set of straight rudder ports that have the newer screwable tightening nut, but then I would have to make the shim that you are talking about to make sure the rudders are straight...It would allow me to use the dripless rudder bearings though...Tide tells me they can't be used with the original ones that I have....At what point do I have to deal with the toeing in of the rudders guys??? Thanks, John

John

When we did mine, we did not set toe in until we hooked up the new steering arms. I assume that is what you are referring too.

John Nardi wrote:.It would allow me to use the dripless rudder bearings though...

Not to talk anyone out of anything...but dripless rudder bearings in my mind are a complete waste.

Rudder shafts do not turn enough to create any heat (the heat is why you allow a drip of water to come in on prop shafts, otherwise you have the packing too tight and you'll fry the packing) so even with the traditional Flax (wax) packing you can snug a standard gland to the point they do not drip while still pretty easy to turn.

My .02...and now back to your regular broadcast show.

Thanks for the reply Carl...I believe I am going to go with the standard stock packing...So do I understand this correctly; once I have the shafts in place, toeing the rudders correctly is done by tension adjustment on the steering arm connecting the 2 tiller arms?? Thanks, John

John Nardi wrote:Thanks for the reply Carl...I believe I am going to go with the standard stock packing...So do I understand this correctly; once I have the shafts in place, toeing the rudders correctly is done by tension adjustment on the steering arm connecting the 2 tiller arms?? Thanks, John

There's no tension in the connecting bar UNLESS a toeing has been set and water flows over the rudder surfaces...

You can toe rudders in when you hook up the jockey bar. Measure and mark center of rudders on trading end, mark and pulling the 1/4" or so you want...and just end ties, pin and done.




So then comes my question of why toe in, or out for that matter?

Running with no toe created a blade wobble, vibration at some spots, a little toe in or out fixed that. If I toed in or out too much boat ran slower. I did this on my boat, dads boat and a buds. All same results...toe in or out just enough to prevent blade from vibrating was about the best.

So why toe in and not out?

To answer the original question about bedding, here's what Bertram did with the 33's. Between the rudder port and hull, Bert used a thickened polyester paste as a shim. They installed the port with the paste, allowed to cure, and then fully bolted the port to the boat. Unfortunately, the resin mixture used in 79 became hard and brittle over time. IDK why but wherever it was used, it was cracking or had cracked in 2011. When I removed the ports, the OEM poly shims literally fell off in pieces.

When I reinstalled mine, I put the rudders in the port with packing, waxed the mounting surface of the rudder port and bolts, used a thickened epoxy paste consistency of thick PB, and then mounted it to the boat. Using the bolts and blocking underneath, I was able to align the rudders straight up and down immediately thereafter. Once it cured, I removed the ports, bolts, took the rudders out of the ports, and reinstalled after sealing with Sikaflex. 6 years later and now using custom made oversized SS rudders, I have never had a leak.

Not sure if Bert used the same manufacturing practices earlier with the 31's, but this worked extremely well for me.

I used bronze bolt.

Thanks for the reply Kevin...yes my 1980 has the same brittle epoxy like substance and thus the source of my original question...I'm going to use the original rudder ports which have an angled flange...The old epoxy was completely flat and no shim to it at all...I'm going to just sand well and 4200 to seal the flange...I think I am going to be the outer circular tube of the port to the hull with thickened epoxy...That is what it came with which I had to chisel out...Best, John