RE: Chassis Speed Building

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Proto87Stores

RE: Chassis Speed Building

Postby Proto87Stores » Sat May 11, 2019 8:18 pm

I'm thinking minutes, not hours, for a properly designed chassis KIT. Every thing that is operational pre-shaped and fits what it is supposed to fit to. No parts to fettle, no parts or partial assemblies that need adjusting or measuring and cutting to size. But you must have an accurate wheel press system if the wheels, axles and gears are supplied as separated items. Didn't the Kitmaster kits go together that fast?

I already make P4 full crossings that are ready in 5 minutes. And close to that per each bogie for our upcoming TRAM, EMU, etc., mechs. I can say that with confidence, because my helper does the first build s and he 's a farmer by trade.

And BTW, IIRC, my teenage years Triang Railways Models had sliding axles on six-wheel tenders.

Andy

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jim s-w
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Re: RE: Chassis Speed Building

Postby jim s-w » Sat May 11, 2019 10:18 pm

Sounds like you are taking the fun out of it if I'm honest

Jim

Knuckles
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Re: RE: Chassis Speed Building

Postby Knuckles » Sun May 12, 2019 8:10 am

I'll reply to my own thred when on PC.

Jim, it isn't all about fun to some people, some of us need to get a bucket load done and need speed, plus if we can make life quicker and easier for people then some will appreciate that. I enjoy modelling but not always every possible task and the scope of some collective tasks are great for one a one man band so speed with the accuracy is very much needed.

All depends on your goals.
“He who dares not offend cannot be honest.” Thomas Paine

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Guy Rixon
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Re: RE: Chassis Speed Building

Postby Guy Rixon » Sun May 12, 2019 10:38 am

If a chassis can be built in minutes from a kit, it follows that the kit eliminates most of the possible mistakes. Otherwise, the build will take either hours, to allow for the anti-cock-up checks, or days, to reverse and repair the cock-ups.

I find kit building much more enjoyable when I know I'm unlikely to mess it up. If I want risk, I can turn to scratch building.

Proto87Stores

Re: RE: Chassis Speed Building

Postby Proto87Stores » Sun May 12, 2019 3:29 pm

My approach is limited to the mechanics. My design criteria is lifted from nearby Las Vegas:

"What Goes on the Track, Stays on the Track".

Whatever the detail and accuracy of what each vehicle is "Wearing", I happily leave to you guys.

Andy

PS Nadel has all the clues on how to achieve that.

Proto87Stores

Re: RE: Chassis Speed Building

Postby Proto87Stores » Tue May 14, 2019 5:02 am

RE: Possible misleading interpretation of my earlier posting.



I can confirm that I was referring to soon making full blown Steam Locomotive Mechanisms from kits in minutes rather than hours, having had experience of modifying and testing such model locomotives since 1956. My above 2-8-8-4's will of course take a little longer that the ones for my simpler N7 0-6-2's and my L1 2-6-4T's. I also have a UK 9F, 4MT 2-6-0 and Co_Bo on my own roster. My earlier mention of (bogie) trams and EMU's referred to already built tested and run versions.

My purpose in creating faster and simpler to make chassis, but of top quality standards and performance, is to enable p87 and P4 modellers, like myself, to easily have a full range and even multiple copies of their various chosen prototypes built and run and enjoyed in one lifetime. And without needless repetition of hand making copies, but therefore not exactly identical, parts, which on the prototypes were standard manufactured items.

In that philosophy, I admire and follow Sir Joseph Whitworth. A shining example of the superb engineering talent hailing from the North of England.

BTW. The SP passenger cars above all have 6 wheel trucks, not 4 wheel ones.

Andy

billbedford
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Re: RE: Chassis Speed Building

Postby billbedford » Tue May 14, 2019 7:36 am

Proto87Stores wrote:I'm thinking minutes, not hours, for a properly designed chassis KIT. Every thing that is operational pre-shaped and fits what it is supposed to fit to. No parts to fettle, no parts or partial assemblies that need adjusting or measuring and cutting to size. But you must have an accurate wheel press system if the wheels, axles and gears are supplied as separated items. Didn't the Kitmaster kits go together that fast?


It's easy enough, all you have to do is reduce the component count and make the manufacturer, rather than the modeller, responsible for the engineering tolerances. Whether anyone would want to pay for them is another matter.
Bill Bedford
Mousa Models
http://www.mousa.biz

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grovenor-2685
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Re: RE: Chassis Speed Building

Postby grovenor-2685 » Tue May 14, 2019 9:44 am

Is any of the stock in the video converted to P87? No way to tell from that video.
Rgds

proto87stores

Re: RE: Chassis Speed Building

Postby proto87stores » Tue May 14, 2019 3:02 pm

No. Neither the locos nor the cars have P:87 wheelsets. Since there are no turnouts on that test loop, all wheels standards could run. There used to be a fully equalized an sprung commercial offering for the 6 wheel coach trucks that could have P87 wheels dropped into. But I only have a couple of those (for reference). So converting the whole train would require another design and manufacturing project on my to do list

My original intentions for the Cab Forwards was to have them running occasionally in the background as moving scenery for my Pacific Electric lines. But I have had them apart to check on the ease of an equalized chassis replacement. Since they are articulated, it's actually a case of replacing them with a 2-8-0 and a 4-8-0 separate chassis. So double the work/time of a worst case single 6 axle loco. I do have quite a variety of old US RTR steamers. So plenty of opportunity to prove out all the various axle configurations. But my GER N7's have priority precedence. You'll see those first.

Andy

Proto87stores

Re: RE: Chassis Speed Building

Postby Proto87stores » Tue May 14, 2019 3:17 pm

billbedford wrote:
Proto87Stores wrote:I'm thinking minutes, not hours, for a properly designed chassis KIT. Every thing that is operational pre-shaped and fits what it is supposed to fit to. No parts to fettle, no parts or partial assemblies that need adjusting or measuring and cutting to size. But you must have an accurate wheel press system if the wheels, axles and gears are supplied as separated items. Didn't the Kitmaster kits go together that fast?


It's easy enough, all you have to do is reduce the component count and make the manufacturer, rather than the modeller, responsible for the engineering tolerances. Whether anyone would want to pay for them is another matter.


Absolutely agreed! Suggest you compare the sideways movement tolerance and component size/count/cost/assembly time of a round rod resting in a Vee Block with that of an un-fettled Horn Block sliding in a loco frame. So I'm anticipating at least 50% cost saving over current methods. And of course a major reduction in assembly and fitting time.

Andy

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jim s-w
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Re: RE: Chassis Speed Building

Postby jim s-w » Thu May 16, 2019 6:20 am

Knuckles wrote:
some of us need to get a bucket load done

All depends on your goals.


Yep. I’d tick that box! :D

Proto87stores

Re: RE: Chassis Speed Building

Postby Proto87stores » Thu May 16, 2019 3:08 pm

The Scalefour Society caters for the needs of railway modellers working to the scale of 4mm/ft (1:76.2), the most popular of the British model railway scales. It promotes and encourages the use of effective modelling techniques and fine scale standards among all 4mm railway modellers with a particular emphasis on the use of scale wheels and track.


I don't see anything in the above concerning the time frame required to achieve the desired results. And if there are individual's or groups' "effective techniques" that can be shown (and/or proven) to work well, but that lie outside of specifically popularized, yet difficult and/or unreliable methods, then for the sake of "all 4mm railway modellers" the Society clearly should promote them, including presumably, on this forum.

Personally, I find the idea that assembling an effective (internal and hidden) chassis mechanism in an hour from precision mating parts is regarded as "speed building", rather than an acceptable norm, rather puzzling. It's not as if one has to wind one's own 7 pole motor, cut one's own gears, and turn one's own wheels and axles to do it.

Andy

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Horsetan
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Re: RE: Chassis Speed Building

Postby Horsetan » Thu May 16, 2019 8:59 pm

jim s-w wrote:Sounds like you are taking the fun out of it if I'm honest..



image.jpeg
image.jpeg (213.85 KiB) Viewed 809 times
That would be an ecumenical matter.

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Guy Rixon
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Re: RE: Chassis Speed Building

Postby Guy Rixon » Fri May 17, 2019 1:12 pm

Proto87stores wrote:
Personally, I find the idea that assembling an effective (internal and hidden) chassis mechanism in an hour from precision mating parts is regarded as "speed building", rather than an acceptable norm, rather puzzling. It's not as if one has to wind one's own 7 pole motor, cut one's own gears, and turn one's own wheels and axles to do it.
Andy


We've never had sufficiently-precise parts in general supply to just put something together without measuring and fettling. Consider:

- Bearings for coupled axles: the hole might be central, or it might be significantly offset, so the axle centres don't match the rod centres.

- Coupling rods: they might have exactly the right centres or they might be a little off, or even different between the rods in a pair.

- AGW-style coupled wheels: the screw forming the crankpin might go in accurately, and at the same throw for all wheels in a set, or the throw might wander a little or the pin go in at an angle.

- Ultrascale coupled wheels: we can probably trust the crankpins to be right, but there's a waiting list at least months long (not in general supply in my book).

- Wheels generally, including for non-powered vehicles: they might be circular, concentric with the axle, perpendicular to the axle and set to the right back-to-back, or they might be slightly off in any of these areas.

- Axle bearings, coned: they have no specific depth of coning and aren't always reproducible between batches from the same vendor.

- Etched gearboxes: they might give good mesh by default or they might need the holes drifting to get that mesh.

- Etched frames: the holes for the bearings might all be in the right places and of a size to accurately locate those bearings, or they might be slack or misaligned.

It's possible to get a bunch of commercial chassis-parts and put them together without checking anything and it does all work first time because they're all fit for purpose...but one would have to be very lucky for that.

In general, none of our components are good enough to build things reliably and quickly. I think things are getting better (except the coned bearings, which are less consistent then 10 years ago), but there's a long way to go before it all falls together in a few hours.

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Guy Rixon
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Re: RE: Chassis Speed Building

Postby Guy Rixon » Fri May 17, 2019 1:36 pm

Here's a challenge: how do I quickly and reliably build motor bogies for models of EMUs and electric locos? This should be simpler than easy-build chassis for models of rod-coupled steam engines, so maybe there's a way to make one in an afternoon without manufacturing parts.

My spec:

- For P4, either including the wheelsets or using wheels that I can readily get.

- Must have spoked wheels of the correct size for the prototype. I might compromise on the number of spokes.

- Must have the correct wheelbase, and the wheelbases for what I would build are shorter than most diesels.

- Must have good electrical pick-up. To me this suggests a flexible suspension even if that is not needed for track-holding.

- Must run well at low speed. Minimally-geared things like the old Tenshodo SPUD won't do. A unit based around an N20 gear-motor might work.

- Must mate to cosmetic side-frames without butchery of the powered unit. I don't might making up brackets to mount the cosmetic bits, but the holes to screw the brackets to the powered core need to be designed in.

- Must carry the body of the vehicle with stability, while allowing the bogie to take up track twist. The mounting of the bogie to the vehicle must be designed in, even if I have to make up brackets to a prescribed form.

If I could get this in kit form, capable of being assembled and working properly in a handful of hours per kit, I'd pay up to about £50 per bogie and buy about twelve kits over the next few years. I'm prepared to scratch-build these bogies, but I'd be happy to solve the problem with money and forego the development "fun".

proto87stores

Re: RE: Chassis Speed Building

Postby proto87stores » Fri May 17, 2019 3:19 pm

Guy Rixon wrote:Here's a challenge: how do I quickly and reliably build motor bogies for models of EMUs and electric locos? This should be simpler than easy-build chassis for models of rod-coupled steam engines, so maybe there's a way to make one in an afternoon without manufacturing parts.

My spec:

- For P4, either including the wheelsets or using wheels that I can readily get.

- Must have spoked wheels of the correct size for the prototype. I might compromise on the number of spokes.

- Must have the correct wheelbase, and the wheelbases for what I would build are shorter than most diesels.

- Must have good electrical pick-up. To me this suggests a flexible suspension even if that is not needed for track-holding.

- Must run well at low speed. Minimally-geared things like the old Tenshodo SPUD won't do. A unit based around an N20 gear-motor might work.

- Must mate to cosmetic side-frames without butchery of the powered unit. I don't might making up brackets to mount the cosmetic bits, but the holes to screw the brackets to the powered core need to be designed in.

- Must carry the body of the vehicle with stability, while allowing the bogie to take up track twist. The mounting of the bogie to the vehicle must be designed in, even if I have to make up brackets to a prescribed form.

If I could get this in kit form, capable of being assembled and working properly in a handful of hours per kit, I'd pay up to about £50 per bogie and buy about twelve kits over the next few years. I'm prepared to scratch-build these bogies, but I'd be happy to solve the problem with money and forego the development "fun".


Guy, Please email me your mailing address and I'll send you a preliminary set up for evaluation next week. Also let me know if you have the means of press fitting wheels, bearings etc. onto 2mm axles and 2mm/1.5mm shafts. Otherwise, it may be the week after next.

Cheers.
Andy
contact@proto87.com


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