It’s the kind of dimension that LBSC didn’t bother with overmuch, as it wasn’t important, just visual! I’d simply scale it from the drawing – it looks sort of 3/8″-ish to me. If you need some better information, you could refer to (say) Les Warnett’s 9F drawings in EiM and scale them from 5″G. Or Martin Evans’ Evening Star drawings might help.

Hi, if you can scan the plans onto your computer. Then in solidworks you can import the drawing and if you have one measurement on the plan you can input, solidworks will scale the rest of the plan for you.

Hi, I know you shouldn’t take measurements from drawings but this evening I’ve printed the drawing in question at full size, that the measurements show, and the points in the O/P’s posts at the top, measure 15/16″ above the bottom of the frames.

Regards Nick.

On 18 February 2024 at 14:44 David Holmes Said:

…I can’t see to find any refrence dimensions to place the feature in the centre of the attached photo. There’s enough dimensions to draw it and place it horizontally, but nothing to indicate a vertical measurement. Am I missing something? Can anyone advise me?

 

 

Like as not  as others suggest it’s cosmetic and doesn’t matter much.  Or a mistake, missed because it doesn’t matter much!  Old plans often have a few blunders, finding them is almost a rite of passage.

Looking at the proportion relative to the measured inset beneath, it’s a shade more than ⁵⁄₁₆”.   Given this is a fractional drawing, I guess ⅜”, maybe ⁷⁄₁₆”.

A CAD advantage is different positions can be tried without doing much work.  You certainly don’t have to find it’s wrong by making one for real.  Dunno about SolidWorks, but SolidEdge lets me select and drag features like that around the model, and it’s very easy to fiddle in 3D until it looks right.

What you’re doing is an excellent way of developing CAD skills and flushing out problems in 2D plans, ancient and modern!

Dave