Avoiding Set Screw Marking

[Ken I]

Here's a tip for avoiding setscrew (grubscrew) marks in your shafting.

Place a small piece of soft solder in before the screw - this hydraulics into place and holds quite firmly without leaving any permanent marks.

Obviously less grip than if the screw bites into the surface but it works for most applictions.

Here I am using it to secure my flywheel to my "6 Shooter" elbow engine - as the cylinders are Aluminium they would otherwise mark quite badly.

In some cases the ridge left by the screw can hinder removal later.

Ken

 

[Mosey]

Would you care to comment on Woodruff keys v. Set screws for holding on shafts?

 

[mklotz]

Lead bird shot works well too. However, almost anything can mark aluminum. Best bet is to machine a flat where the setscrew seats. That way the mark won't interfere with removal.

 

[Ken I]

Mosey,
Set screws are a fairly "rough & ready" method but nonethess practical for a lot of modeling applications.

For my industrial designs I generally wouldn't use them - sticking to P&W & Woodruff style keys and even cross drilled tapered pins.

On my beam engine I went to the trouble of making a double taper "Clampex" coupling - looks good - but an awful lot of work when a grub screw would suffice.

Marv, point taken - I was thinking more along where you might need to use it as a point of adjustment.

Ken

 

[dalem9]

Nice looking fly wheel . Dale

 

[Dunc]

Second the comment about the nice work quality.

Are the spokes cartridge cases? And is there a story here?

 

[Ken I]

Yup - you can follow the build thread here :-

http://www.homemodelenginemachinist.com/index.php?topic=16790.0

That's the engine on the marquee this month.

The cartridge case flywheel makes its appearance on page 5 of the thread.

No story other than the elbow engine cylinders reminded me of six-shooter cylinder and I just continued with that "theme".

Ken