Upgrading to the Raymarine linear drive

M

Mike Oldak

.
Jan 22, 2008
323
Hunter 34 Herrington South, MD
We upgraded our boat to the Axiom system and later found out that our old autopilot with a wheel drive wasn't capable of doing all the new capabilities. So we upgraded to the new autopilot with a wheel drive that looked identical to the old unit. We kept getting low voltage errors and the system not responding properly. Raymarine told us that he upgraded autopilot wheel drive was no longer strong enough for a H34 and that they gave us a deal on another upgrade to the EV200 with the linear drive.

The next task was to figure out how to install a linear drive on a H34. There are at least two options, buy the Edison short arm or fabricate an attachment plate. I tried to figure out how to mount the Edison short arm underneath in the aft cabin, but while it would attach above the rudder drive wheel, there was really no space for the HUGE linear drive assembly. The other option was to install it in the lazarette, which would be renamed the linear drive bay (since it would require a major framework that might take up most of one side of the lazarette. I decided to try and use my engineering degree (electrical NOT mechanical) to design something that would be secure, reliable and not take up too much room. We decided that it was worthwhile to take up some headroom in the aft cabin rather than half the lazarette.

I'm in the middle of the fabrication, which actually is not that difficult and will provide more pictures as we finalize the installation, but thought I might get some advice from others that have attempted a similar fabrication, if any.

Using 1/8 stainless steel, I cut two plates and drilled four holes in the rudder drive wheel. I've attached the plates to the drive wheel with 4 two inch 5/16 SS screws. I instant glued about 10 SS 5/8 (?) washers together to provide a solid shim between the two plates so that I could really tighten the linear drive bolt to my plates. I'll add a second set of bolts and washers to the inner side of the plates so that the plate won't be torqued by the linear drive bolt when I tighten it down. Everything seems to be working appropriately.

I located the linear drive to the port side and installed a 12 x 20 x 1 inch starboard inside the bottom of the lazarette to spread out the torque. Plus two 4x4x1 starboard pieces to go under the linear drive bracket so that the drive arm was parallel to the drive wheel. I also found out the forward and aft positions for the drive bolt so that the total swing of the arm during operation was minimized (hopefully under their 5 degrees.

I should have some "final" photos next week.

Any suggestions?
 

Attachments

  • Like
Likes: kloudie1
M

Mike Oldak

.
Jan 22, 2008
323
Hunter 34 Herrington South, MD
kappykaplan said:
Not a Hunter, but here's what my installation looks like:
View attachment 228920
View attachment 228921
Click to expand
Looks GREAT did you do the welding? Unfortunately there is really no spot for the Edison arm under our drive wheel and not sure if I really want to shorten the rudder post housing to install the short arm. I do have a welder, but I think my fabrication should work and save the $800 for the Edison short arm. I would need to weld up a mount if I had installed it in the lazarette. THis is not my boat, but it shows how little room there is on a H34 to install an Edison short arm. I could cut the rudder post, but that would mean that the linear arm would be that much lower into the aft cabin.

auto helm rudder install.jpeg
 
kappykaplan

kappykaplan

.
May 1, 2011
4,721
Pearson 37 Lusby MD
I purchased the type 1 linear drive and rudder angle sensor from Defender. I paid the boatyard a flat rate for the installation. All in for the boatyard was $5800.
 
M

Mike Oldak

.
Jan 22, 2008
323
Hunter 34 Herrington South, MD
I think Raymarine just made an incredible mistake in requiring 34 foot boats to use their linear drive since the new wheel drive motor can't handle what the old wheel drive motor could. If I had known that my $1500 upgrade would require a $5800 install, I would have just left the old autopilot in place and forgone the new features. As it is, everyone would have to buy at least the $800 Edison short arm, except if they can do or get a fabrication like I'm doing.
 
kappykaplan

kappykaplan

.
May 1, 2011
4,721
Pearson 37 Lusby MD
I agree. I went through the same thing. Replaced the old wheel pilot with a new one and was very unimpressed with its lack of performance. I've been quite pleased with the linear drive, despite the expense. And yes, the short Edson tiller was an expensive piece of metal!
 
A

artboas

.
Jun 1, 2009
1,808
Hunter 49 toronto
kappykaplan said:
I agree. I went through the same thing. Replaced the old wheel pilot with a new one and was very unimpressed with its lack of performance. I've been quite pleased with the linear drive, despite the expense. And yes, the short Edson tiller was an expensive piece of metal!
Click to expand
I believe that the linear drive will definitely handle a 34 foot boat better than the wheel drive; especially with difficult conditions .
While you already have the linear drive, I’m wondering if you gave the rotary drive any thought? With your mech knowledge, this might be an option, and I’m confident Raynarine wouid cooperate
 
smokey73

smokey73

.
Oct 26, 2010
2,023
Hunter 40.5 Beaufort, SC
I have the rotary drive on my 1994 40.5 Installation was easy and did not cost an arm and a leg. It works well and I am very pleased with its performance.
 
M

Mike Oldak

.
Jan 22, 2008
323
Hunter 34 Herrington South, MD
smokey73 said:
I have the rotary drive on my 1994 40.5 Installation was easy and did not cost an arm and a leg. It works well and I am very pleased with its performance.
Click to expand
When I called RM with the problem of "Low Voltage" and they told me the newer wheel drives weren't as strong as the old ones, they told me to buy the linear drive.
 
M

Mike Oldak

.
Jan 22, 2008
323
Hunter 34 Herrington South, MD
FINISHED! Here are the pictures from my ~$200 install kit to mount the linear drive to my H34 rudder wheel. There was no room to mount an Edison short arm underneath the deck, and trying to mount it in the lazarette would require a welded steel structure or something and take up most of the lazarette. So, I decided to make my own attachment kit with two1/8-inch stainless steel plates (Amazon $29 each), a large 3/4-inch piece of starboard (Amazon $48 much cheaper than you know who), and about $50 worth of stainless-steel bolts, washers, etc. Essentially, I sandwiched the rudder wheel between two the two sheets of 1/8" SS and drilled 4 bolts through the inner rim of the wheel. To properly locate the 4 holes in the rudder drive wheel, position on of the SS plates above the wheel and track the inside of rudder wheel, then move in about 1/4 inch to what would be the middle of the inner wheel and drill the four holes. THEN mount the two plates and drill through the rudder wheel and the second plate. Then instant glued SS washers together to provide a spacer for the drive bolt from the linear arm. I also drilled 2 holes on the very inside and used glued SS washers to offset squeezing the outside of the SS plates.

I installed the 1-inch starboard in the bottom of the lazarette to provide a more secure base for the linear arm mount and two 3/4 inch ~5x5 inch starboard block on the ceiling of the aft cabin to lower the linear arm so that the arm was parallel with the rudder wheel (cut offs from the Amazon 12x27x3/4 starboard). I positioned the linear arm perpendicular to the middle between where the drive bolt was at its maximum aft position (rudder midship) and left and/or right max. This kept the linear arm swing within the max swing requirements.

It may not be the prettiest result, but we were designing as we were building and like Michaelangelo, I did it all on my back.

For a better explanation look at owner upgrade articles.
20241216_115151.jpg
 

Attachments

Last edited:
smokey73

smokey73

.
Oct 26, 2010
2,023
Hunter 40.5 Beaufort, SC
Mike Oldak said:
When I called RM with the problem of "Low Voltage" and they told me the newer wheel drives weren't as strong as the old ones, they told me to buy the linear drive.
Click to expand
Just for info, I was referring to a "rotary drive" not a wheel drive. It fits inside the binnacle and drives the wheel by a sprocket that is attached directly to the shaft of the wheel, not a "wheel drive" that attaches to the wheel that is then driven by a motor. I had one of those and it barely handled the 40.5. However, you linear drive self made kit looks like it does the trick nicely. Only clarifying for others that might be inclined to look for solutions to the lack of power of the newer rotary drives. Of course my installation was easy and straightforward since the 1990's Legend Series boats of this size were designed from the factory to accept a "rotary drive" so it was basically already set up for the installation. YMMV
 
You must log in or register to reply here.

Top Bottom