Fixing a bit of a hiccup.

[James NewberryParticipant @jamesnewberry]

[James NewberryParticipant @jamesnewberry]

Hi Folks,

I've got myself into a mild pickle with my Stuart Victoria build. Where I've machined the cylinder top I've managed to mess up the bolt spacing such that, rather than forming a nice hexagonal pattern they are a good way off and it looks a mess. I'm pretty confident it's nothing that would affect the running but it's going to annoy me so I'd like to redo it. My plan of attack is to make up a new cylinder cover with the holes drilled in the right places and then re-drill and tap the holes in the end of the cylinder. In the places where the new holes in the cover overlap the old ones in the cylinder I'm planning on filling the old holes with JB Weld or similar.

Couple of questions now – the original cylinder cover is made from cast iron. Is there any reason why I couldn't use brass for this? I only ask because I have a suitable piece of brass in the scrap box whereas I would have to order a piece of cast iron specially. To my mind, I can't see why brass or cast iron would make a difference, but then I'm quite new to all this and there may be a reason I haven't thought of in terms of differential expansion or something.

Second question – is my JB Weld idea going to cut the mustard or do I need to do something else? The alternative that I have thought of is to drill out the holes to a larger size and fit plugs of cast iron (being the same material as the cylinder itself) held in place with Loctite. I saw this method used by Keith Appleton in one of his Youtube videos.

Finally, is there any reason why I would need to plug all the holes or can I leave the ones that don't overlap the new holes? I may get lucky and find that none of my new holes overlap the old ones in which case I am not planning on plugging anything – is this likely to cause any problems with weakening the cylinder wall?

Many thanks for any help or suggestions.

Jim.

[JasonBModerator @jasonb]

Brass will be fine

The problem with using JBW is that the drill will want to follow the path of least resistance and wander into the softer JBW. Better to tap the holes if not already done, put in a screw of threaded rod with loctite or JBW, flush off to teh cylinder top when dry and then redrill your holes.

Happens to us all, this is steel threaded & loctited into CI

Just do the ones that overlap

Edited By JasonB on 24/11/2014 13:48:36

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