3/16 or 1/4 inch clevis pin on Vang

Mawill

New Member
Hello,

Was all excited this week - got the upgraded vang - and like a present with no batteries - there is one problem.

The hole on mast tang is 3/16th of an inch diameter. The clevis pin on the vang assembly is 1/4 inch. Now - what to do?

Option 1a -
I could get a new Mast Tang with the correct diameter hole but that means drilling and re-riviting the mast - potentially weakening it.

Option 1b -
Use the original clevis pin - the 3/16th one in the new vang. It has a head that is big enough, but am not sure that it is strong enough - my assumption is that I would bust the boom before I broke a stainless steel pin - but I am not an engineer.

Option 1c -
Drill the hole out to 1/4 inch. Could do this, but if I had a nickel for every drill bit I have melted attempting to drill SS....

Opinions?

Thanks
Matt
 
Matt,

Just drill out the hole on the mast tang. Use a sharp bit, medium speed - and put a drop or two of oil on the tip of the drill bit. Most any oil will do (not WD-40).

Slow, steady pressure, and you will cut right through. Remember, you are only enlarging an existing hole, not making a new one. Much less wear and tear on the drill bit.
 
Hi,

Thanks for the advice.

I did try drilling it yesterday (using a neighbors drill bit) and well - drill bit is no more. I used WD40 so maybe that was the issue. I guess I will give it another go.

Thanks
M
 
Nothing against WD-40 - it is a wax-based product and good for what is was designed for.

You need a cutting oil on the bit to lubricate it and help it cut throught the SS. Any heavy oil (like motor oil) will suffice.

Medium drill speed, moderate pressure - you can do it!
 
Since you owe your neighbor a bit, do yourself a favor and buy a new 1/4" bit, drill the hole and give him the bit when you are done. A new bit will cut SS easily, just follow the advice above..
 
The key to machining SS is to always keep the bit cutting.

Don't let the bit spin at all. Stainless is actually pretty soft, but it work hardens very easily. That happens to the surface when the bit turns against it (instead of cutting away a layer) and suddenly the bit is trying to cut a layer nearly as hard as it and it dulls or breaks pretty quickly.

So, the best technique is fairly heavy feed pressure and moderate/slow turning speed. Start the bit cutting immediately and press hard enough to keep one steady curl coming off the bit. If you loose it and the bit spins a bit, just stop, let everything cool off for a moment, and start again.

Any heavy oil is helpful as a cutting fluid. Too much is better than too little.

Cheers,

Geoff S.
 
Humm -

So - this all makes sense - BUT - I have already melted a bit on this once.

Does that now mean that the SS is 'Work Hardened' and if so, does that change your advice.

Thanks
Matt
 
Most likely the bit was already dull and/or drill speed was too fast. I've done the same thing in the past when in a rush.. In the times when I've done that, as soon as I put in a new bit and slowed the drill down, I had no issues drilling thru the SS.

So, it's even more important if you have work hardened the SS to drill with a new, fresh bit. If you have only drilled from one side so far, start drilling from the opposite side.
 
as soon as I put in a new bit and slowed the drill down, I had no issues drilling thru the SS.

Ditto my experience.

I'm not a materials expert, but what I suspect happens is that the SS surface hardens and the drill-bit quickly dulls rubbing against it (it may also loose hardness due to the high temperatures that can occur if you just "press harder" to try and muscle your way through the problem). At that point it's over for that drill bit, but a new sharp cutting edge can cut through the thin hardened layer and keep going.

Cheers,

Geoff S.
 
Option 1c -
Drill the hole out to 1/4 inch. Could do this, but if I had a nickel for every drill bit I have melted attempting to drill SS....
I used a small round metal file, opened the hole just a hair, then tapped the pin through with a small ball peen hammer. It may never come out again, but it worked.
 
you certainly explore all the options in re: to drilling a 3/16 hole out to 1/4 lol. get a 1/4 drill bit and just drill it already!!
 

Back
Top