steering line replacement.

[john]

I have a job that the owner of a older 38 Bertram wants the lower steering lines/hoses replaced. Its a capilano steering system. I guess now its seastar solutions. There specs say copper or 1000 psi equivalent hydraulic hose. Copper is going to be tough as its a old boat and ots just not that easy to run the lines with bends. Looking for ideas on the hydraulic hose to use. Stainless jic in some areas like the rudder most likely. Very pricey though. Thank you in advance.

John

Topic

[john]

Before and after

[john]

Well I finished this project today. Was a pretty large job for my standards. Way more than what was initially planned. If you look at the before pics earlier in this thread and after it is a pretty dramatic improvement. I cantlevered the ram off the rudder plate. Attaching another plate. I had to strengthen the hole rudder supports on both side. Relocated autopilot pump and raw water pump. Custom rail mounts to make replacement easier. Installed a smx rudder travel indicator. Most of the wiring was laying in the bilge and now is overhead under the deck. A big thank you to To y and everyone that had input on this.

[john]

We are on the right page. I didn’t see a edit button anywhere to edit my response. The point where the angles become a parallelogram at full extend and retract is the ram placement.

[Tony Athens]

When the geometry is RIGHT ( regardless to the total rudder arc) , there should be a STRAIGHT LINE thru the center-line of the ram between full extension and full retraction.. Study the drawing some more. it will confirm that 100%……..

See if you can sort out the attached drawing I put together over 20 yrs ago.. Most have no clue what it is trying to show…

Tony

[john]

So I have been looking at the ram placement for a few days now. Took a few days off to let it sink in I guess. So here are my thoughts. Then I am drilling holes. When looking at the offset angle The ram should be parallel with the tie bar connecting the two rudders together. Any more angle and you start to loose any mechanical advantage when being hard over(ram fully extended) Also fully retracted will be the same angle. Roughly pushing at 90 degrees when fully retracted. That how I came up with the ram offset. Right train of thought?

[Tony Athens]

Look at the attached drawing..

It’s all there.

Tony

[john]

I was playing with the ram angle geometry some with the time I had today. It is only a slight angle now. I see how the angle gives the mechanical advantage when going hard over. It seemed ok but will see how it feels with more angle. Thank you!

[Tony Athens]

Now you are talking.. Good job.. A few comments in the attachments.. Run every thing back & forth a few times before you commit to drilling..Look at all as to binding , geometry, etc, etc, etc.. Assemble all with copious amount of grease between all and use a thin piece of PVC or ?? between the ram base and the aluminum.. You’ll thank me 10 years from now..

I’d say you are on the right tract..

Tony

[john]

Hard over port and some closer shots

[john]

Hard over starboard

[john]

I realized that when i looked at it it was tough to tell anything. I did a much better job today of a mock up. I might have to email the pics to myself to post them. Here is one of the rudders centered

[Tony Athens]

John,

I really want to help, but I need to see it all.. Your picture does not really do it.. I know you know what you see, but I cannot look past what you take a picture off.

Need some decent pics or my hands are tied

Tony

[john]

Looking at the post the number its 4.91 on the measurement form the center of the ram shaft mount side to the center line between the rudder. So the offset is about 1.1 inches

[john]

I’ve been probably overthinking this. Here is my last mock up. Pretty much the same as the drawing with two rudders. I have 6 inches between the rudder post and ram ball joint. 5.91 inches from the center line between the rudders and the center of the cylender shaft on the mount side. Looking at different pictures some appear quite a bit more angled. Tell me what you think. Thank you!

[Tony Athens]

Vertically in relation to the tiller/tie rod connection, the ram has to installed to where at full travel, NOTHING BINDS.. The ball joint gives you some flexibility that way, but we always shoot so all in in the same plane…

Post a good pic BEFORE you commit as to what GEOMETRY you think you want..

I am here to “SEE”..

Tony

[john]

Getting ready to start drilling some holes. I’m following the third drawing from the last post by you tony. Tiller came off relatively easy. One question I have is about offsetting the ram. Do you put the foot of the ram in line with ram or on the same plane as the tie rod? Or since its hinged it doesn’t matter. I’ve seen it both ways on different drawings. I’m leaning toward the same angle as the ram. I keep looking over the drawings and info and was wondering also what the term rudder fold means?

[Tony Athens]

Study the drawings well along with being sure the geometry is right .. It does not matter whether you end up with 70, 75, 80 83, or 90 degrees of total arc.. But what ever, there is correct place for ram orientation for any arc set-up.

[john]

I Thought about as well. There was a hole already for the easy install so went with the easy option. I will look in the morning. It is a square rudder post so even if I can not drill from the top I should be able to take it off. Pretty sure its bronze also so should be easy to drill. So I guess the HC 175 B-7C would be the in between option. I will look and order tomorrow if it looks right. Steering 101 will be over soon! Thank you

[Tony Athens]

John,

You have been doing your home work—-GOOD!

Now give this a thought since I know you are about to redo all in the rudder area.. Can you re-drill the tiller to about 5-6″ where either the tie rod attaches or the ram attaches and use a 200-7 Ram?.. That will give you a “in-between” upgrade in ram push vs. turns lock to lock and still give the rudder arc needed ( 70-90 degrees)

Compare the drawings and geometry..

Tony

[john]

Tony,

Here is some of the info you wanted.
Upper helm hynautic h21 2.75 cu inch
lower helm h21 hynautic 2.75 cu inch

Old ram was a k22 hynautic. 13 cu inch displacement.

With the old system it was a little less than 5 turns lock to lock. Hard to turn with one finger and one hand on the wheel no problem, 19.5 od on the wheel.

So here are my calculations and thoughts.

Using the seafirst HC 150 b-9 you would get similar rudder movement forces similar and about 4.8 turns lock to lock. Looking at the bigger displacement ram ( hc loo b-9) you get about 1/3 more displacement at 20.5 cu inch so 7.45 turns lock to lock. Easier to turn the wheel, but more turning to get the rudder to react.

The boat is a 38 Bertram. Twin qsb 380. 95 percent of the time the boat is run 10 knots and below.

I ordered the hc 150 b-9 but told kevin to hold off shipping after I talked to you. If you need pictures I can attach them but will have to make them smaller to post.

Thank you!

[Author]

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