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.
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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
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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 2089 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

Proto87Stores

Re: wheel Crud derailments

Postby Proto87Stores » Thu May 23, 2019 4:53 pm

Whether it makes sense to build a large exhibition layout in P4 is a separate issue. Count your wheels, look for Sunday-morning wheel cleaning volunteers, and then maybe insist on air-conditioned venues only. Image


Image

Image

After reading about Heckmondwike's dirty wheels, today I pulled one of my P:87 Coaches from it's storage drawer, and scanned the wheels as above, where it had been put last May as a result of the workshop move. The coaches were put away with no maintenance done whatsoever, and have never had any wheel cleaning despite being demo run on the one scale mile oval tracks. every few weeks over the period of about 7 years. The workshop conditions included always open roof skylights, concrete black walls and no internal temperature or humidity control despite outside temperature varying from 100F to 30F with occasion heavy rain but mostly dry wind blown grit and dust from the adjacent ocean beaches and local industrial works. Plus a slow but constant down fall of dirt and termite droppings from the bare wood high ceiling and beams. If you've never experienced model track work covered in termite droppings, you'd better hope the UK's climate change doesn't end up as termite friendly.

Wheels are solid Nickel Silver, as is the code 55 FB rail used. The track was cleaned originally at laying time. Unfortunately my helper used a "Bright Boy" abrasive rubber while I was away, and that needed a major track refinishing ( and a serious talking to ;) ) by using brass metal polish to restore the rail close to the new rail's original smooth, corrosion resistant top. Subsequent track cleaning, but only after each time of months of neglect, was done by pulling a alcohol wiping wagon around the track.

Why this is the case may be due to some or all of the following (not very P4) practices:
The coach trucks are 100% only, but accurately, equalized as primary suspension.
Springing is restricted to coach bodies only. Coach weight is around 9 oz. each.

I have some very simple solutions to rail joggles and set, but I'll cover those at another time.

Andy

Proto87stores

Re: RE: Chassis Speed Building

Postby Proto87stores » Fri Sep 27, 2019 3:32 pm

First shot at a truly "Fast and Easy" working suspension N7 loco chassis sent off as part of my regular etching orders today. Plus an update of the Airfix wagon chassis that should be able to use the existing Airfix floor instead of a substitute. There are quite a lot of extra items in the former, so the risk of CAD "typos" is quite high. If enough stuff works, Hopefully I'll be able to post a positive update after a test build around the end of October.

Andy

Proto87stores

Re: RE: Chassis Speed Building

Postby Proto87stores » Fri Nov 01, 2019 8:51 pm

Image

I quickly threw together one of the trial sideframes for the N7 chassis last night. It took about 5 minutes, 'cos I was going really slowly first time and checking what I was doing at each stage. My next step is to make some chassis spacers so I can make the frames into a box and put some temporary wheels in.

I was originally going to put folded etch spacers in the fret, but I realised that if I used insulated axle bearings, and insulated spacers, I could have split frames and avoid the need for separate pick-ups. But of course I have to make up some spacers from plastic before I can do that. Unfortunately my schedule is full this month, so it will be a while. Eventually , the spaces can be very quick and cheaply 3D printed, but I have make some prototypes first. (Knuckles please note?).

The chassis working suspension spec is +/- 1mm of track twist over the full wheel base and +/- 0.7 mm of individual wheel movement. The "Horn block" slots are open ended so the assembled wheel sets can be pressure inserted/removed after assembly. Sideframe width is standard 0.75 mm. Overall chassis width is set by the particular spacers used. The finished chassis is externally rigid and the loco body can be fitted directly to it or via springy points for

Note that even at this stage the wheel bearings are absolutely accurately aligned and will fit the coupling rods without any adjustment or alignment needed. This design is for a specific 0-6-2, but is the same design works for any 2-6-0, 4-4-0, 2-4-2, 0-4-4 or 0-8-0 with only the inter axle spacing changed. Other 6 coupled designs will need a slightly different beam arrangement.

I have done nothing new about the design of coupling rod pins and other valve gear. That's a problem for another time. So those will still have to be fitted traditionally.

Andy

Edit: Sideframe width corrected to 0.75mm

billbedford
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Re: RE: Chassis Speed Building

Postby billbedford » Sun Nov 03, 2019 7:40 pm

Even the GER inset the rear frames so that the pony truck would stay on the track.
Bill Bedford
Mousa Models
http://www.mousa.biz

Proto87Stores

Re: RE: Chassis Speed Building

Postby Proto87Stores » Sun Nov 03, 2019 8:14 pm

billbedford wrote:Even the GER inset the rear frames so that the pony truck would stay on the track.


Yes. I have the Isinglass drawings. Although in those the frames appear to be tapered inward rather than joggled to form a parallel inset.

This a proof of functionally stage, so I'm avoiding any distraction hassle of being perfectly cosmetic. I already have a couple of improvements in the pipeline before a final etch run. But this design allows for you to bend the rear of the frames inward if you so wish. It would make no difference to the functionality, except to give you an even smaller min operating radius. I wasn't contemplating anyone using absolute scale frame separation. It's not as if most modellers would want the same model frames to realistically protrude though the footplate underneath the smokebox.

I did unintentionally fib about the assembly time. I have some 1 mm assembly screws belatedly on their way from China. So, in their absence I tacked a couple of parts together with solderin the meantime. My apologies ;)

Again this just an extension of the same design amd manufacturing technology I used in the bogies. I wouldn't describe the bogies as merely "better running". They just meet their zero operating defects/problems design specification. There hasn't been any derailment or other problem since they were first assembled or installed, so I don't foresee any difference for the loco chassis.

Andy


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