Tiller arms on the cheap??

http://www.anderswallin.net/2006/11/cnc-machined-tiller-arms/


The above link shows some cnc machining of tiller arms. It also shows an incredibly simple tiller arm at the bottom.

Does anyone know how to do some tiller arms for under $100?

They don't need to be as expensive or as complicated as they are.

Thoughts on simple, cheap ones?

 

There are lots of them for sale for under $100 apiece. But then, you don't say what size or what material they need to be, or what type of rudder post they connect to, such as round, square, keyed etc.

 

That homemade tiller is a really bad design. The point of a bolt is the only thing keeping it from spinning loose. There should be a woodruf key.

 

The link looks like it pertains to "model" yachting- probably fine for that, but agree for a real boat unacceptable.

I've a couple of times in the past done rudder head/tiller fittings that include a fabricated box that cradles the top of the stock, two bolts act transversly through the top, these stocks were staino tubes of about 65OD with around a 6mm wall in catamarans.
Snowbirder needs a compact arrangment to fit within steps/boarding platform of a 15M cat so may not have the height for above.

Jeff.

 

I agree the lower image of the cheap tiller isn't well thought out. If there's a flat on the shaft, the bolt should be fine threaded, the hole cut to the "D" shape and then maybe it'll take some torque. A key would be helpful, though difficult to machine in the garage. A pinch assembly could be easy to make, but these tend to slip too. Personally, I'd just find an exact fitting to go over the shaft and weld an arm on the darn thing, screw the CNC work, just hefty, stout and easily repaired if it takes a dump.

 

Whoops.

Sorry for the lack of information.

2" O.D. 316L rudder shafts x2 since it's a catamaran. Thet are kick up rudders in cassettes so while PAR's idea is the most appealing, I'd like to stick to a bolt on setup so I can disassemble the thing easily.

I have no metal working tools and cannot neatly and easily drill straight holes through the extremely hard, round 316L shaft, nor work with any metal nicely apart from aluminum.

I'm trying to get out of this the quick, cheap, production boat way.

Don't care what the material is, but they are outdoors. So... stainless, aluminum, maybe bronze.

 

Wait... I think I see what PAR is saying.

Find an exact round fitting, like a shaft collar, to bolt on and weld an arm to that fitting.

Sounds perfect.

 

Yes, something like this from Grainger Supply, 2" ID x 3" OD stainless.

1L653Shaft Collar,Set Screw,1Pc,2 In,SS
1L653
Set Screw
1
2"
Stainless Steel
3"
Check Availability

$47.10 / each


DAYTON
Shaft Collar, Set Screw, 1Pc, 2 In, SS
Item # 1L653
Mfr. Model # 1L653

Catalog Page # 175

Price $47.10 / each

Technical Specs

ItemShaft CollarDimension TypeStandardCollar StyleSet ScrewNumber of Pieces1

Bore Dia.2"MaterialStainless SteelOutside Dia.3"

 

Looks like a good start,

these fittings usually hold the rudders in too, need more than a single set screw even in a dimple to achieve safely, these rudders are in a 50' powerfull sailing cat, might do 20+, rudders maybe 3-4? square feet each.

Snowbird still needs to develop his metal skills/capabilty or take the pieces to someone with them especially for welding. A lot of the cutting for this style of thing can be achieved with a steel rule, square & scriber, 5" grinder with cutting & grinding/flap discs, horse & clamps/vice & PPE especially visor also use cutting discs carefully between around 1-3 oclock, a chinese 16 speed drill press will drill staino & come in handy on lots of other jobs in the low 100s or just mark up & centerpunch for the someone else to drill, even take your own drill bits.... pressure & cooling is important on staino.
Jeff.

 

Thanks, Jeff. You've got all the numbers correct even converting to imperial units!!

I'm about to launch. This is some of the only metal on the boat, apart from some aluminum bits here and there. For this reason, I probably won't be buying a drill press. I have to outsource this one.

What do you suggest instead of just the single set screw? Through bolt?

 

I'd use a pair of bolts...... very agricultural but simple, besides transmitting rotational loads they will hold the free hanging spade rudders in the boat/cassette, you need some bearing surface incorperated at the bottom of the tiller fitting, sometimes the top bearing is a tophat style with this, other than that some donuts of nylon sheet- even cutting board wil do- it's only tuning through 70-80 degrees, oil filled nylon sheet like ertalon is good for this, can be machined like wood.....
the grub screw I would replace with a set screw(prolly at 90degrees from bolt /s with a dimple or locat flat) - the stock is not fast rotating machinery so pretty safe & then you can work on every component with adjustable spanners.............
Set up should be pretty careful especially with staino & tight tolerances, very easy to set up a burr that locks stuff up.
There's plenty of other options for keying & set screws.
Jeff

 

Cool. Thanks. I agree with the bolts. Seems perfect, except I'll need help drilling these 316L shafts. Stuff is so hard I can't even cut the extra stock off nicely.

The cassettes already have built in Delrin bushings, so a nice sliding surface is ready to accept the tiller arm/rudder stop.

 

When we splashed I didnt bother to put on the rudders, because we were in a hurry to leave before dark. I thought that I could make it a few miles up the river under power ,(twins) OK enough without rudders and then fit them later on. Mistake. I couldn't get her to turn and was lucky to get back to the dock.

 

I'm missing tons of stuff too, but I felt rudders would be pretty high on my list.


That's a funny story.

I have a 1000 mile trip up the Eastern Seaboard ahead after launch... first stop, Cape Fear. Im skipping that snaking, 4,000 mile Georgia intracoastal.

I'll be motoring the whole way up, since a rig is out of my budget for a year at least.

Basically, the exterior is done to a level I can now move it. The interior has a crew room and galley done, allowing me to finish the other rooms and main salon while at anchor closer to sources of income.

 

Ha ha ha. Good, cheap, fast - pick 2. You're trying for 3 out of 3, never happens.

A machine shop can easily square the tops of the shafts and make matching drive plates, or key the shafts and make matching bushings. I like a setup like the taperlock bushings with keyway myself but that's custom machining in stainless, it works really well but you wouldn't like the price.

A bolt bearing on a flat or in a dimple on a round shaft, having a significant side load, on a mission-critical component like a rudder, is way, way under-engineered.

Pay a machine shop and get on with life. You can't properly do crap like this with hand tools and the odd cheap drill press anyway. The fact that you think stainless is hard is revealing enough because it's not. It *work hardens* if you play with it but that's a sign you don't have the horsepower to take a proper cut.

PDW