45CC Wall Wizard

[Jo]

 

Having thought on the gear problem I have decided it would be better to Loctite a sleeve to the camshaft rather than sleeve the gear. I have justified this to myself as:

The sleeve is going to be 9.53mm O/D and 7.94mm I/D which is rather thin and once turned up not very wide either.... Loctiting it on the crank will be against a flange whereas in the gear it could be pushed out  And I think the sleeve on the crank could possibly a bit wider.

I considered boring out the hole and putting in a bigger bush but that increased hole size would be even closer to the mounting holes and the gear centre has to be thinned down.


The important question is do I do it before or after some gardening 

Jo

[Jasonb]

As the sleeve is a bit thin walled you could loctite a thicker one on and skim it down in situe, Step the OD if you don't want it to slide out and counterbore the gear to suit.

Shame you did not look at the gears first as you could have turned the shaft with a larger diameter.

[Jo]

The gardening won out yesterday so hopefully I can get back into the workshop today and finish off the camshaft gear and the sleeve.

Yes JB I intended on turning up a larger diameter sleeve and loctiting it on the camshaft then turning it once the Loctite is fully cured.

Suddenly with a crankshaft and a camshaft in the cases the build begins to look a bit more engine like and each little bit made becomes more significant

Jo

[Jo]

Having made the necessary studs for holding the cylinder covers on I realised  that because this engine has ball race it needs to have bolts rather than studs to hold the covers on so I had the opportunity to make some bolts after I had already made all the studs    This is not all bad as I could make the bolts with reduced head size rather than having to make a bunch of reduced A/F Nuts to use which always look horrible 

Finally with the camshaft and crankshaft in place I tried turning over the crank to find it jammed.  This was tracked down to the cam hitting the followers due to the guides being 0.5mm over length. this gave another opportunity to dismantle everything to take the guides out and the cam follower guides were taken over to the BCA, clamped to the bed and the unnecessary bit skimmed off (while some idiot got the pic out of focus  )

I still have not worked out why the drawings show a blind hole between the two follower holes on the cam follower guide  To finish the day I have now hardened the faces of the cam followers which means it must be time to go and find out which casting set Surus thinks is due a fondling this evening - assuming I am allowed near any of them 

Jo

[Vixen]

Jo,

The Wall is becoming a very interesting looking engine. You are lucky to have the casting set, hacking that crankcase out of a billet would have taken a long, long time.

How old is the design? The fractional dimensions in inches, dates it rather.

Mike

[Jo]

Hi Mike,

Yes the Wizard is an interesting engine but I would not call it pretty. I am sure someone like JB would happily hack a prettier looking crankcase of a bit of bar stock like he did with the Stuart lightweight (but he used the wrong material so we will always know it is a copy not an original by just picking it up )

All of the Wall engine designs are pre war, many of the designs seem to mirror what Westbury did in the UK only the Wall engines are bigger   

Jo

[Jasonb]

Bit of yellow paint on that crankcase will pretty it up

I can't think of a reason for that extra hole in the guides, it is not really a light engine so can't see it being done to save weight.

The only Wall engine I like the look of is the horizontal single, if anyone should have a set of drawing please let me know.

https://www.flickr.com/photos/15794235@N06/29044361916/in/album-72157670117040594/

[Roger B]

As you say it's looking more like an engine  The middle blind hole is a bit strange, maybe it's a relic from a previous design. Wall certainly had a number of designs, but probably nowhere near ETW.

[Tennessee Whiskey]

I’m taking notes and making mental pictures, as I have a set of these castings aging under the bench. Don’t think I’ll be at the pay grade that qualifies machining for a few more builds yet. I sure hope I have castings and drawings that are “non Jo” i.e. undersized castings and incorrect drawings. Poor gal seems to get all of her and Surus’ stuff like that  . 

Big E

[Jo]

Have I mentioned the connecting rods yet Big E 

Often with these earlier engines the original (1930's) patterns were made in wood and somewhere over the years they were used to make aluminium masters, or often they used an existing casting set, either of which already had shrinkage so if you used them as a pattern so you would get double shrinkage 

The good news is that none of these engines are high precision 

Jo

[Vixen]

Hi Jo,

Would it not be better to machine the simpler, higher stressed items, such as conrods and pistons from a solid billet. That way you get it to the exact size and made of known material. Crankcases and the like are often better from a casting.

Mike

[Jasonb]

Or if you want to keep the supplied conrods alter the Wrist pin position and or head of the piston to compensate for any loss of length then you can keep to the designed compression ratio.

[Jo]

I have already made the pistons out of the supplied piston castings and they have been fitted to the cylinders http://www.modelenginemaker.com/index.php/topic,8215.msg176619.html#msg176619

Part of the challenge of using castings to make model engines is to overcome any shortfalls in the castings if all else fails then I can always resort to the easy way out and use bar stock but I don't like to give in without at least trying to use the supplied castings.  Its like I enjoy the challenge of sorting out Orphaned models

Jo

[Vixen]

Hello Jo

Agreed, always better to use the supplied castings, whenever you can. I thought you had a problem with seriously undersize castings due being copied (perhaps several times) from previous casting rather than the master patterns.

Mike

[Jo]

Morning Mike 

These are castings from Betty Coles - we are not sure of the vintage.

They are not one of someone else's specials - he has the sense to coat the original castings with a thick dollop of paint to take up the shrinkage 

Jo