Had Another Go

[David JuppParticipant @davidjupp51506]

Nigel,

The ‘spare piece’ that you can’t delete.

If in part workspace – right click on the spare bit in the workspace, choose ‘show feature in explorer’ – this will highlight it in the Design Explorer – you can then delete it.  You may have to repeat if the spare pieces is actually several features.

If in assembly workspace, simply right click on the spare piece and select Delete.

[Julie AnnParticipant @julieann]

I run Alibre Design Expert, so have a mirror function in the assembly space. But I don’t recall having ever used it.

If the intent is to make one chassis rail that will work for both sides the original rail and the mirror need to be identical, and to have rotational symmetry. It seems unlikely that the chassis channels will be mirror images right down to every hole and bracket. The rails need to have rotational symmetry as any hole or feature not on the centre line will be off when the part is rotated to the other side. It would be sensible to model the two chassis rails as seperate parts, left and right.

Julie

[Julie Ann]

On Julie Ann Said:

I run Alibre Design Expert, so have a mirror function in the assembly space. But I don’t recall having ever used it.

…

Julie

Quite so!   Mirroring an assembly is an advanced operation, rarely used I imagine. Wanting to mirror an assembly causes a red light to flash in my mind! The requirement could be bad.  Might be clever and legitimate, or a misunderstanding.  If a misunderstanding, don’t mirror assemblies!!!

The most common reason for mirroring an assembly I guess is to create Left and Right hand versions of the same item.  Something like a disc brake assembly for a car.   But designers avoid specials: much better to design a brake that’s neutral so it can be fitted to either side.

My guess, which could be completely wrong, is that Nigel wants to mirror his chassis rail.   Mirroring parts and sketches is normal and common, but the resulting RH and LH pair are incorporated separately into a single assembly.  Though it contains mirrored parts. the assembly isn’t right or left-handed.

Nigel:   Learning how to mirror an assembly at this stage of your CAD apprenticeship might be a confusing time-waster.  Analogous to bashing one’s brain with matrices at school when they are never needed again…

Which assembly do you want to mirror, and why?  The answer may be “don’t”!  A different approach might be better.

Dave

 

 

 

 

[JasonBModerator @jasonb]

Nigel, I have said several times when giving suggestions that mine may not be the same as yours particularly the arrangement of icons at the top that is because I have Alibre Professional.

It’s a bit hard knowing exactly what was pared down to make Atom more affordable and I also have to remember not that you are on V27.

Like Andrew I don’t often mirror in assembly but did actually use it for the current engine as after placing two of the base corner columns the other two were just the same on the other side of the engine. Also down the tree you can see the side and end panels were mirrored. This saves having to apply several constraints to the individual parts had I imported 4 legs and two of each panel.

 

[Nigel Graham 2Participant @nigelgraham2]

David –

Thankyou. Found how it was listed in Design Explorer and that I could delete it there.

I certainly agree about Matrices – an extremely specialist area but unfortunately they were part of the standard school mathematics course I took for work purposes, so I had to learn how to “do” basic ones even though not taught anything else about them, including need.

At least CAD tools like Mirror do have obvious meanings and uses… and if their hidden maths uses matrices those stay safely hidden in the box of electronics.

.

Julie –

Ah, well, that’s the difference. Alibre Atom is a bit more limited and its Assembly functions do not include Mirror.

No, the side-rails are not identical to the last bolt-hole, but I cannot design the thing to that level of detail and much of it is largely already there.

It’s only now, to design and make the engine and transmission-gearing, that I need half-decent workshop drawings. Unfortunately that machinery will occupy the area I can’t draw properly in CAD, and that area might be the wrong shape anyway!

The two bits of steel are the same despite rather rough-and-ready fabrication methods. I placed some primary bolt-holes by clamping the rails back to back, but with it now assembled, drill through from the components I am fitting.

The chassis has plenty of spare holes now, by the many changes in inching slowly towards building the vehicle.

 

The horrible thought, from the one useful works photograph, is that I should have swan-necked the chassis in the very short area between the front of the machinery space, and the rearward front spring mountings – a displacement of over an inch sideways in about four length. (20.6º)

That would need completely new longitudinal members, probably need new boiler mounting brackets. It could give give major difficulties for the steering-column and gearbox, right in that transition area. (Ackermann steering)

The two pairs of joints would need hefty filler and cover-plates bolted or rivetted on. Possibly the full-size method impossible to determine from the surviving photographs – and every Hindley wagon seems different from its brothers in details anyway.

On the other hand it seems more true to original, relatively easy and quick to do, allow correcting one or two other mistakes, and facilitate putting the road-gears all within the chassis, as correct, in a nicely-rectangular area.

A further option is an all-square layout, basically two rectangular frames end-to-end with the smokebox forming the front cross-member. Simple and mainly hidden detail, but possibly not very structurally sound and prototypical.

 

Any angled form would just as hard for me to draw in CAD than the present version.

 

The transmission seems to have been two-speed on the larger “Standard” wagons at least. Those were undertypes with the machinery all mounted from the rear axle, and the driver had to dismount to change gear. I can’t work out how the ‘Light Delivery Van’ mid-chassis gearing was arranged. All I know is that the tapered chassis I have made, has unwittingly hampered replicating the transmission reasonably faithfully in miniature. I did not receive the single crucial photograph giving hints, until well after completing it.

 

[SillyOldDuffer]

On SillyOldDuffer Said:

On Julie Ann Said:

I run Alibre Design Expert, so have a mirror function in the assembly space. But I don’t recall having ever used it.

…

Julie

Quite so!   Mirroring an assembly is an advanced operation, rarely used I imagine. Wanting to mirror an assembly causes a red light to flash in my mind! The requirement could be bad.  Might be clever and legitimate, or a misunderstanding.  If a misunderstanding, don’t mirror assemblies!!!

The most common reason for mirroring an assembly I guess is to create Left and Right hand versions of the same item.  Something like a disc brake assembly for a car.   But designers avoid specials: much better to design a brake that’s neutral so it can be fitted to either side.

My guess, which could be completely wrong, is that Nigel wants to mirror his chassis rail.   Mirroring parts and sketches is normal and common, but the resulting RH and LH pair are incorporated separately into a single assembly.  Though it contains mirrored parts. the assembly isn’t right or left-handed.

 

 

 

Meanwhile, everything here(and the rest of the chassis)

was designed on one side, and then mirrored around the centre line. You can see the join in the rear  crossmember:

All of the flat parts are copies of the first part and are intended to be laser cut to save time, work and be self-jigging because slot and tab construction is effectively free. The wishbones and hub carriers are intended to be built in the same jigs, although the caliper brackets will need to be handed.

Although it looks complete, it’s mostly guesswork for a general arrangement and ‘what else do need to know?’ For example, the rear suspension geometry is atrocious.

 

Mirroring the parts saves so much work!

[Nigel Graham 2Participant @nigelgraham2]

Nick – you are right in what I had wanted to do. My lorry’s chassis is simple (well, in physical form it is) and symmetrical in all but small details. Also I had not realised the Mirror tool is such a trap for a novice like me. Best avoided then…. along with Sweep.

……

Here she is, some 18 years ago and not much advanced since (two house moves in that time don’t help), posing outside the ruins of her ancestral home in the Dorset village of Bourton. The building on the left is recogniseable in some of the advertising photographs taken almost a century earlier. I had the boiler and some other parts with me, but left them in the car. Sorry about the low-quality scan of the proper photograph.

[Author]

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