Metal bashing

[Graham_Wright]

The top end of my 1" rudder post is formed into a 'male square taper'....

Onto it fits a block of s/s which has a 'female square taper', mating with that above. The nut is to retain this in place.

Welded onto the rear/side of this block is a short horizontal tube which takes a through-bolt, permitting the end of the tiller to secure to the above assembly.

I'd like to have the above s/s block reproduced, using the original as a template. How involved, please, would be the cutting of the 'female square taper'....? What sort of gear is necessary?

Cheapest would be four pieces of plate welded in the corners and then turned in a four jaw chuck if you wanted a circular outside. I have had collets wire cut and it ain't cheap but produces a good finish. I'm not sure it could produce tapers though.

At a DIY level, a series of holes at the smallest square and with the smallest holes in the corners could be feasible.

How thick is the boss? Plasma or flame cutting could be another route although there would be a lot of finishing to do.

 

[30boat]

Cheapest would be four pieces of plate welded in the corners and then turned in a four jaw chuck if you wanted a circular outside. I have had collets wire cut and it ain't cheap but produces a good finish. I'm not sure it could produce tapers though.

At a DIY level, a series of holes at the smallest square and with the smallest holes in the corners could be feasible.

How thick is the boss? Plasma or flame cutting could be another route although there would be a lot of finishing to do.

I'm also for welding four plates at the corners and then shaping the outside as required.With,say,6mm thick metal the welded structure will be very strong.

 

[john_morris_uk]

That depends very much on the grade of stainless selected and deep hole drilling in stainless can be a real pain if you're not set-up for it

It's all basic apprentice skill test stuff and relatively simple in a good workshop, however you’d probably want to make an exact copy of the male as a gauge.
I don’t think I’d want to be doing the final shape on a boat

I completely agree with the 'drilling can be a pain' but I seem to recall the OP is working on the boat which is laid up at or near his house and workshop. A pillar drill, cutting and cooling compound and an engineers vice to hold it while you fettle away would be almost essential to do a good job.

 

[sarabande]

have spare big bench drill if you want to borrow one to DIY. Well capable enough to drill SS blank.

Or what about that company in Westbury you visited on my behalf ?

 

[30boat]

Drilling stainless is very doable but a powerful pillar drill,sharp cobalt drills and loads of cutting fluid are important.I do it all the time but my milling drilling machine weighs 300 kgs.Not huge but more than capable .

 

[boaterbaz]

Just flicked through the replies, some of the more fanciful methods would probably cost more than a new rudder/stock design of a simpler design!
If I had to make that square taper using simple tools, I would make it in two halves either sawing and filing the taper with hand tools or if a shaping machine is available using that. the two sections could then be drilled and tapped together or even weld. Long winded and time consuming admittedly but doable with easily obtained tools. Good luck.

 

[30boat]

Just flicked through the replies, some of the more fanciful methods would probably cost more than a new rudder/stock design of a simpler design!
If I had to make that square taper using simple tools, I would make it in two halves either sawing and filing the taper with hand tools or if a shaping machine is available using that. the two sections could then be drilled and tapped together or even weld. Long winded and time consuming admittedly but doable with easily obtained tools. Good luck.

I could make a female square taper fitting in a few hours for that rudder stock.It's definitely not a complicated project.

 

[macnorton]

You could get one cast cheaper?

 

[jdc]

I could make a female square taper fitting in a few hours for that rudder stock.It's definitely not a complicated project.

+1, except I'd be tempted to make a trial piece out of material which is easier to work than Stainless Steel, such as Aluminium 6082-T6 which is readily obtainable and cheap. It might well be strong enough as is, but its main advantage I think would be to reduce the chance of making an error and having to start again when making the real stainless piece (which will be some hours of tedious and hand-ache inducing work!)

 

[30boat]

+1, except I'd be tempted to make a trial piece out of material which is easier to work than Stainless Steel, such as Aluminium 6082-T6 which is readily obtainable and cheap. It might well be strong enough as is, but its main advantage I think would be to reduce the chance of making an error and having to start again when making the real stainless piece (which will be some hours of tedious and hand-ache inducing work!)

Grinders are wonderful tools
Agree with everything you said.

 

[Avocet]

Is that off the Cutlass? Avocet's doesn't look anything like that! It's a huge (bronze, I think) casting with two wings that come forwards off it with a gap between them, between which the wooden tiller is inserted and secured with two through bolts. As far as making a matching female taper, it might be worth considering getting something water-jet cut? I had a one-off set of sundial numbers and markings water jet cut from brass and it wasn't THAT expensive. Yu can water jet cut 6" steel plate, so you might be able to get something like that done.

 

[pmagowan]

There are only really two options;

1) DIY; do it whatever way seems easiest with the tools you have. Making it in parts seems most likely.

2) local fabricator; hand him part, say "make another one of these", pay money and let him figure out the process.

Unless you have lasers, plasma, water cutters etc then the method is more or less irrelevant. Metal fabricators make metal things (it's in the name) and will likely have a good idea of how they will cope but, at the end of the day, that it their problem. Your problem is signing the appropriate cheque!

 

[prof pat pending]

A distinct lack of response from the OP, but there are far more than two options here.
I guess it’s time I put my money where my mouth is….So!!!!!



Oldbilbo, if you’d like the job done properly, I’ll design it for you as a one piece part (no welding (even the tiller tube)) FOC.

I’ll give you some manufacturing options from the modern world (I can do all of the above mentioned methods, but during the last 32 years of hands on making hi tech products I’ve learnt better)
I’ll suggest the suppliers based on experience, but the rest is up to you.

I can’t guarantee the design unless I get to do the reverse engineering, but if you have the tools and are confident send me the measurements.

Unless you commit to a part, all you have to lose is my time

 

[oldbilbo]

A distinct lack of response from the OP, but there are far more than two options here.
I guess it’s time I put my money where my mouth is….So!!!!!



Oldbilbo, if you’d like the job done properly, I’ll design it for you as a one piece part (no welding (even the tiller tube)) FOC.

I’ll give you some manufacturing options from the modern world (I can do all of the above mentioned methods, but during the last 32 years of hands on making hi tech products I’ve learnt better)
I’ll suggest the suppliers based on experience, but the rest is up to you.

I can’t guarantee the design unless I get to do the reverse engineering, but if you have the tools and are confident send me the measurements.

Unless you commit to a part, all you have to lose is my time

Second PM en route

 

[ffiill]

If it were me I would set to work after careful marking with the flat face of an angle grinder cutting disc.
So long as you have a nice light grinder I find you can do some quite accurate work.
If it were just a squared off end no problem whatsoever using the same technique.

 

[DownWest]

Slightly different idea occured. Cut a series of plates to make up the height, say 8mm each, then cut a square in each one to match the size at that position. Quite easy to drill a hole in 8mm and file the corners out in the vice to match the taper. Then weld them all together. Stick welder with correct rods would do. Probably take me a couple of hours or three.

 

[30boat]

Slightly different idea occured. Cut a series of plates to make up the height, say 8mm each, then cut a square in each one to match the size at that position. Quite easy to drill a hole in 8mm and file the corners out in the vice to match the taper. Then weld them all together. Stick welder with correct rods would do. Probably take me a couple of hours or three.

It's a lot less work to cut four triangular plates to fit the flats ,bevel them at the edges and weld them together.The whole thing will tighten up as it cools but as it's piramidal just make it slightly longer than the male taper and cut the excess off the top.

 

[DownWest]

Yes, but I was thinking of the bit for the cross bolt, which would just be extra plate. Probably would do it your way and add the rest. Except, welding would be off the job with a stack of plates.

 

[Graham_Wright]

Cheapest would be four pieces of plate welded in the corners and then turned in a four jaw chuck if you wanted a circular outside. I have had collets wire cut and it ain't cheap but produces a good finish. I'm not sure it could produce tapers though.

At a DIY level, a series of holes at the smallest square and with the smallest holes in the corners could be feasible.

How thick is the boss? Plasma or flame cutting could be another route although there would be a lot of finishing to do.

Pictures as promised.
Crude but cheap and effective and can be made as strong as you like.

 

[30boat]

flame cutting could be another route although there would be a lot of finishing to do.

Pedant.Flame cutting doesn't work on stainless.