Wooden Cam Shaft, is it possible?

[WIGdj]

G'day Folks,

I thought I would come straight to the experts as I want to make a decorative cam shaft out of wood and was wondering if it's possible to do on a lathe from start to finish? I have experience in wood turning but only round objects, never any offset turning which i assume is required for such a thing.

Cam shaft components aren't all round, some are tear drop shaped, is that achievable on a lathe or do those parts need to be finished by hand?

Cheers

Dan

279778

[artme]

Considering golf club woods - when they were made from wood - were tyrned on
7 axes I uess anything is possible.

A cam shaft should, by comparison, be relatively simple. After all they are turned for engines!!

[chuck1]

hi Dan I think it's doable you will have to draw it up to work out all the centre's it will need to be turned on, maybe a few trial and error ones will happen

[WIGdj]

hi Dan I think it's doable you will have to draw it up to work out all the centre's it will need to be turned on, maybe a few trial and error ones will happen

So would i need to balance it somehow? I imagine it would shudder quite a bit turning off centre or is that part of the planning?!. Is there a way of balancing a piece of offset turning timber, would a steady work?

Maybe i'll take it down to the golf shop and ask them to make it :D, 7 axis lathe sounds like a fantastic piece of gear.

Good idea re doing a mock up first and then remembering the recipe.

[RETIRED]

To do a proper camshaft shape a rocking head AND tailstock would be needed unless you want a lot of hand work to get the cam profile.

[WIGdj]

To do a proper camshaft shape a rocking head AND tailstock would be needed unless you want a lot of hand work to get the cam profile.

Cheers for that , I've done some googling on rocking tail and head stock and I can see what you mean. It would require some more hardware investment. I think the elbow grease may be getting a workout before i go to that far.

Thanks for the input fellas :2tsup:

Dan

[Skew ChiDAMN!!]

It should be a relatively simple matter to turn the bulk of the camshaft, leaving discs of wood where the cam lobes will be.

I'd also leave it mounted in the lathe to use it's indexing facilities (assuming it has them, of course!) to mark out the high points of the lobes - and any secondary marks to define the cam profile - on the discs for easier carving. Just so you get the 'timing' right.

[WIGdj]

It should be a relatively simple matter to turn the bulk of the camshaft, leaving discs of wood where the cam lobes will be.

I'd also leave it mounted in the lathe to use it's indexing facilities (assuming it has them, of course!) to mark out the high points of the lobes - and any secondary marks to define the cam profile - on the discs for easier carving. Just so you get the 'timing' right.

I think that's the way i'll do it Skew, as it's the simplest without having to buy more gear for the lathe, plus it'll allow me to read the grain as to where the high and low points should be shaped.

I want to make a table as a house warming present for a mate who builds hot rods as a hobby. The cam shafts will be the legs that will start narrow at the base and gradually increase in diameter towards the top where the cog will be. I have to make four of the suckers :oo:

Thanks for the ideas :2tsup:

[KBs PensNmore]

Hi. How wild do you want the cam lobes to be? If they are offset round it shouldn't be much of a problem. How many lobes are you planning to put in? Do you plan on making it for a V8?
I could have a go at drawing up the offsets on the comp for you, if you have problems working it out.
Kryn

[rwbuild]

How about getting an old cam shaft from an engine reconditioner, copy the dimensions, etc, scale up the size to suit the table

[WIGdj]

Hi. How wild do you want the cam lobes to be? If they are offset round it shouldn't be much of a problem. How many lobes are you planning to put in? Do you plan on making it for a V8?
I could have a go at drawing up the offsets on the comp for you, if you have problems working it out.
Kryn

Hi Kryn,

Thanks heaps for the offer, rwbuild made a good suggestion of getting an old cam and copying that. I can then draw it up in ACAD to get the proportions right as i want to exaggerate / taper it and then make some mock ups in MDF before using real timber.

The number of lobes will depend on proportions as the lobe width will increase as the diameter does, yet the lobe depth will decrease as the diameter does so it's not a dust collector.

I always make miniatures of all of my projects so will start with that first, as it uses less material before i get to 1:1 scale mock ups.

I'm making the cam for table legs, so depending on the proportions it may turn out to be a brand new engine size, should i patent it then sell it to GM? :rolleyes:

Cheers
Dan

[WIGdj]

How about getting an old cam shaft from an engine reconditioner, copy the dimensions, etc, scale up the size to suit the table

Fantastic idea :2tsup: i may just do that. My neighbour has trucks which are for ever getting parts replaced so will ask him if he has any cams i can use.

[Skew ChiDAMN!!]

Sounds like it'll be an interesting project.

Don't forget lotsa pix for a WIP! :D

[Evanism]

The main body, bearing surfaces and lobe bodies you'd do all with conventional turning.

To get the lobes into needed egg shapes, youd use a method as seen in this video: Milling a camshaft (with EMC2) - YouTube (http://www.youtube.com/watch?v=YnABuOOoi5w)

Rather than from the top, you'd do it from the front side with a jig and a smaller hand router. The jig would only let you slide/move it up and down. You'd move it by hand. You'd also rotate the piece by hand. It would be very useful if the lathe had indexing with, say, 5 degree stops.... Rotate a bit, route, rotate, route.

Don't forget each cam is offset by 360/n-cylinder and they are paired to inlet/exhaust. For the sake of simplicity, offset the inlet/exhaust by 30 degrees.

But, if it didn't have small stops, use what you have, route out what you can then use strips of sandpaper to smooth them out.

Your query interests me as I've built quite a few absurdly powerful engines over the years and have seen the cams made for me. The machines that make them are fantastically complex.

Pictures needed and progress pix too! :U

I just had a thought, doing a crankshaft would be infinitely easier....

[oreos40]

This isnt that difficult. if you have a lathe that can handle the length and diameter of what you want to turn. Turn the journals and disks for the lobes round first as a blank. mount a cam between centers (behind or in front of, your choice) the blank in the lathe. mount a pivot shaft further outside of the pattern. set up a router in one end of a teeter totter type arm that can be fixed to the pivot shaft. you will have to fix the rotations of the master (the metal cam) and the work piece. fasten a board on edge under the teeter totter board that will be the stylus to follow the lobes. If you angle the master to the other two centers the machining process will scale up or down accordingly as you move from one end to the other. set the location and carefully drop the router end of the teeter toter board as you rotate both master and workpiece.

There was a paddle/oar manufacturer that made oars/paddles this way. He used a dado blade on a spindle and the motor counterbalanced the spindle. The material shaping/copying is the same though.