Cam Grinder on The Go

[Charles Lamont]

The cam grinder is finished and has sucessfully ground a camshaft for the Westbury 'Seagull'. When I say finished, I have not yet built the bit to oscillate the rocking frame side-to-side over the width of the wheel. I just moved it slowly by hand instead. It needs doing, as I had a overshoot and one side of the adjacent cam is no-longer quite perfect. Overshoot too far and the cam template could fall off the side of its shoe.

The pictures actually show things after I had finished the job and cleaned up. I did not want to mess about with photography while I was trying to concentrate on making cams.

In practice the areas behind and below the workpiece would be stuffed with kitchen paper to collect the overspray of coolant, which went everywhere except out through the wheelguard drain pipe. I found I had to put a pretty tight squeeze on the liquid pick-up pipe to reduce the flow enough to just keep the job wet, even with the air tap little more than cracked open.

A minor annoyance is that there is really no way to get a mic across the cam in situ. The shaft has to be removed for measurement. On the other hand, it does help prevent getting grit in the micrometer.

Additional bits not shown are a block for mounting a wheel dresser on the 'tailstock', a height gauge to transfer the height of the top of the wheel to the pivot bar (a requirement for preserving the correct geometry), and a synchronising gauge for the setting the cam template and the camshaft 'catch-plate' in phase.

 

[dsage]

Will you be checking your finished cams against the expected profile? I find a good way is to mount an indicator vertically in the quill of your mill with a home made tip the same size as the lifter you expect to use (important).
Then mount the cam under the quill in a rotary table so it lifts the indicator. Use the rotary to measure the degrees of rotation and plot against lift as measured on the indicator. I'd be interested to know if you get the cam profile you expected i.e. - valve opening and closing points, lift, duration, fluctuations on the profile etc. etc.

Let us know what you find.

Thanks

Sage

 

[Charles Lamont]

Will you be checking your finished cams against the expected profile?

No. I am satisfied that I made the templates to the correct profile, and that, when set up correctly, the geometry of the grinder correctly reproduces that profile.

 

[Shipdisturber]

Beautiful setup great workmanship.

 

[Brian-in-Oz]

Nice to see your grinder up and running and grinding some lumps for your "Seagull". Have you or are going to have a build thread for this engine? I am currently procrastinating on my next build and tossing around ideas as diverse as a 14 cylinder radial to a single cylinder with rotary valve but neither of these two use a conventional camshaft so I will probably settle on something with a conventional cam so the cam grinder can be put to use. Sorry for being a bit slow in responding but I have just got back from NZ after escorting my sons German in laws on a holiday of both islands. Helps that us Aussies and the Kiwi's sort of speak a similar language.
Cheers and keep up the good work - Brian :thumbup:

 

[Charles Lamont]

Brian, I am not doing a thread here, but at:

http://www.charleslamont.me.uk/Seagull/home.html

although at the moment I have only written up as far as April 2015.