Canal Crane Error

[Sub MandrelParticipant @submandrel]

Error in gear centre dimension

[Sub MandrelParticipant @submandrel]

I'm aghast to discover there is an error my drawings for the frame of the canal crane.

It's not 100% clear what the spacing of the centres are for the two gears and the most likley conclusion from the drawing would be 1 3/8".

It should be in the region of 1.180" or slightly more.

I suggest making your gear pair first and adapting your frame to suit – not forgeting that you need to have adequate space for the chain drum.

My thanks to Peter Bramley for spotting this and letting me know.

Also apologies to Peter and anyone who has wasted time and metal on this error.

I will check & redraw that part of the drawing and post a correction.

Neil

[Paul LousickParticipant @paullousick59116]

Hi Neil,

Join the club. I am not building a canal crane but have found that the supplied drawings cannot be trusted and are riddled with mistakes. I re-draw and double check everything before I start cutting steel. I work as a professional draftman and the drawings which I have been supplied would be rejected by our workshop.

I suppose though, that you only get what you pay for. The set of drawings which I received cost less than $100. If they were drawn properly and checked they would have cost $1000's.

Paul.

[Anonymous]

Paul: I think you'll find that Stub is referring to the canal crane wot he designed and drew, and which has been recently serialised in ME, not to a set of drawings which he bought. I normally skim through most ME articles, but I did read the canal crane series all the way through.

Andrew

[Paul LousickParticipant @paullousick59116]

My mistake, thanks Andrew

[JasonBModerator @jasonb]

Neil while you are at it the square ends of the rods have been dimensioned with a diameter symble, may well be the illustrators error or just a quirk of the programme you have used. Text and the way its drawn show it a square.

Edited By JasonB on 26/02/2013 07:55:58

[Ian S CParticipant @iansc]

Jason, do you mean the pinion, and Winding Drum Spindles? If you don't want to set up the milling machine, these would only take a few miniutes with a filing rest in the lathe. Ian S C

[JasonBModerator @jasonb]

Ah but how long will it take me to make a filing rest. Still if you think it will allow me to make 3/32nd diameter squares they must be good.

[Anonymous]

Simple, all that's needed is to square the circle, and then fit the resulting square peg in a round hole.

Andrew

[Sub MandrelParticipant @submandrel]

Here's a rivised drawing of the lower part of the frame, dimensions taken from the model:

You can see my drawing package enters a leading '0' before the fraction – I can't find out how to supress this. I think this is what was interpreted as a diameter symbol when the spindles were redrawn.

Another thing to watch is that the lower frame spreader must be made with care to avoid interference with the flanges of the cable/chain drum. the dimension for the flanges seems to have got lost – it should be 3/4".

My apologies for the errors – in answer to Paul, all can say is they haven't cost anyone £100, I've made the corrections as quick as I can (I have sent the correction to Diane as well), and if I had to work to industry standards then I and many others would not be able to contribute to the hobby in this way.

Please – if any other errors are seen, do speak up.

Neil

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