Stuart Beam

[Chris Taylor 3Participant @christaylor3]

Can anyone tell me how the Watts parallel motion links on the classic Richard Beel model, were made? Rather than the standard flat version, they are beautifully turned fish bellied shafts with perfectly circular bosses. Are the shafts turned separately and screwed or bonded to the bosses, or are they filed in one piece? Any ideas?

[bernard towersParticipant @bernardtowers37738]

My Stuart Beam Has the rounded ends and fish bellies and I built it with an accompanying book so I would think that the method is in there somewhere. will try to look it up when I have a minute.

[JasonBModerator @jasonb]

It’s the same method as any other fish bellied rod just on a small scale.

I would start with round stock, mill flats and ream the holes. Cut overlength, face and ctr drill the ends. Turn three facets and blend to bet the belly. Finally cut off the waste material at each end and round them over either with filing buttons or on the rotary table. Bit of needle file work if you want round ends or leave as is for “D” shape. This sort of way

[John PurdyParticipant @johnpurdy78347]

Chris

See my post in the “Stationary Engines” topic “Sanderson Beam, dated 20 March 22 17:40” on how I made the fish bellied links with rounded ends for the Sanderson. Might give you some ideas.

John

[Chris Taylor 3Participant @christaylor3]

Thanks John, I have the book and it shows the flat versions, I can turn the fish bellied part, it’s how to do the circular end that’s puzzling me, photo…

[JasonBModerator @jasonb]

Mill most of it with a small dia cutter on a rotary table then blend into the fishbelly with a needle file.

Some people silver solder round rings onto round or bellied material.

[John PurdyParticipant @johnpurdy78347]

Chris

The way I made mine was to drill/ream the holes in the 1/8 x1/4″ stock at the appropriate distance, with the end hole a sufficient distance in from the end to allow a small centre to be put in the end for tail stock support while turning the fish belly so that when the end is rounded off the centre would disappear. Then mount in the 4 jaw, with the outer end  running on a live centre, to turn the fish belly section. Cut off from the parent stock leaving sufficient for the rounded end. I then mounted them on my small rotary table and milled the round ends with a 1/8″ end mill, stopping just short of the fish belly to leave a small square section as visible in the pic below. (or you could then blend it into the fish belly with a needle file as Jason suggests if you think it would look more aesthetically pleasing).

John

[David-Clark 1Participant @david-clark1]

They look very nice John.

[lfoggyParticipant @lfoggy]

I made these by machining from solid, cutting tapers with the topslide and then finishing with a hand file and abrasive paper on the lathe….

[John PurdyParticipant @johnpurdy78347]

Thanks David, still needs painting but can’t decide on a colour scheme. Will have to wait till next summer anyway as we are into the cold rainy season out here on the west coast.

John

[David-Clark 1]

On David-Clark 1 Said:

They look very nice John.

Yes indeed – they look really ‘right’..

[Chris Taylor 3Participant @christaylor3]

Thanks John, that’s one method I was contemplating but wasn’t sure if it would work. Your results look really nice. I was slow replying to everyone because the email notifications went into spam for some reason, probably a different email address being used to send them.

 

 

[John PurdyParticipant @johnpurdy78347]

Chris

If you go with a method similar to what I did, here is a snipit of my notes showing how I laid out the stock material. From the notes it appears that the material supplied for the links was 3/16″ x 5/16″, where as the plans call for the links to be 5/32″ thick with 5/16″ dia. eyes. My notes don’t say, but I must have milled .015 off each side before turning the fish bellies, as else where in  my notes I list the eyes as being .160 thick (just measured them and they are .160). For the centre I used a #1 centre drill, drilled in 3/32″ point depth as shown. I laid out a link on each end of the supplied bar so I had plenty to hold in  the chuck. After turning the centre section to 5/32″ dia. I turned the fish belly by setting over the top slide 1.9 deg first one way then the other to taper the ends for the dimensions shown below then blended the three sections together with a fine file and abrasive paper. I used a 3/32″ wide parting tool with a semi circular end to turn the tapers so as to leave a fillet at each end. Hope this might be of  some use.

John

[Chris Taylor 3Participant @christaylor3]

Thanks again John, that is really useful, I will use that method.

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