c 1" Tooling Ball needed or Advice Please
 

Ladies and Gentlemen,

I hope you are all staying safe in these uncertain times.

I'm about to drill the oblique port holes in my 6" Scale twin cylinder casting. Joe Pieczynski (USA) has just posted an excellent (to a newbie like me) Youtube Video on this and uses a Tooling Ball.

I can't find any for sale in Europe - all available have to be ordered from the USA with substantial Postage etc.

Does anyone have one for Sale / Hire please? Or does GB Engineering use a different tool and if so what is it please.

As ever your guidance / advice will be very gratefully received.

Kind regards.

Andrew

I imagine a 1" ball bearing would do. Look on eBay first. I suppose bearing suppliers might have them,but you'd probably need to buy a whole lot.

Never heard of one , so perhaps could you post a link to the video , it sounds interesting .

Does it have to be a 1" ball? I have a 1/2" one that you would be welcome to borrow. It has a 1/4" stem (if I remember correctly).I can measure it properly if it is of any use.
Regards
Brian

Thank you.

Here is the link : https://www.youtube.com/watch?v=KjQscFVgQgU&t=185s

A 1/2" would probably do - I went for a larger simply because I'm building in 6" Half-size scale and hence the cylinders are 3" diameter. Having said that I feel 1/2" should work just as well!! I'll pm you.

Kind regards,

Andrew

hi, you can buy single balls (bearings) online, i got a single 2" ball from " the bearing boys" or "the bearing guys" online for £11 delivered.
stay safe,
chris.

You could use the full balls or hemispheres from a Moore and Wright tramell set for that

Strangely I watched that you video ( I do like to watch a bit of Joe at times - often pick up a little tip), the ball thing was new to me. He is building a stationary engine in a series of videos I believe. He is easy to listen too.

I’m completely lost as to why the design calls for an orphaned stud in the middle of 2 ports.
Why not rotate the stud pattern by 30 degrees and drill a single port?
On a full size, surely that must significantly weaken a casting?

How about, making the bung up with a centre drill dimple in it and gluing ( Araldite ETC) a ball in place.

I think that would be accurate enough.

Accuracy
 

Yes I've been thinking about that especially with the links to Ball Bearing Manufacturers / Sales Outlets. The key is its accuracy as a small degree out at the base will quickly be exaggerated the further out you go (Yes I know there will be a phrase / definition name for this but, sorry, don't know it).

If, as replies suggest, this side of the 'Pond' we don't use a Tooling Ball here - how do you achieve the same ie centering above a cylinder (3" dia in my case) thats at 20 degree angle to the X Y axis - or do we just eyeball it?? (I guess eyeballing will likely be more accurate than a minimally misaligned ball bearing.....?)

Kind Regards,

Andrew

Careful marking out to find your centre,then pick up the centre with a centre in drill chuck or collet. Or the venerable "sticky-pin".

Now that I have had a rethink and watched the video right through I think Henry Maudslay's method above would work fine.

But note that you will probably still have to calculate the distance B, D, + the distance to your holes depending on your drawing information.

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