Ideal starter wagon chassis?

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MikeH
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Ideal starter wagon chassis?

Postby MikeH » Mon Jul 06, 2015 9:38 am

Hi all,

I am thinking about getting a sprung chassis kit for a wagon (maybe to convert something rtr) and probably to be used mainly to test out my track/point work but also to see if I can do it basically. So I am wondering what kit you guys would recomend for a beginner?

Cheers

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Simon_S
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Re: Ideal starter wagon chassis?

Postby Simon_S » Mon Jul 06, 2015 12:19 pm

Hi Mike,
The easiest conversion I've done was of a Bachmann air-braked van - just remove the original w-irons (attached with one screw), remove the boss that they pivoted on, and replace them with Bill Bedford's sprung units using the original screw.
HTH,
Simon

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Guy Rixon
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Re: Ideal starter wagon chassis?

Postby Guy Rixon » Mon Jul 06, 2015 3:36 pm

Bill Bedford's separate axleguards are nice because their spacing across the wagon is good with typical bearings and standard (26mm) axles: i.e. they set the axle end-float for you. You have to: set up the wheelbase; make sure that the brakes don't drag; find the right packing to get the buffer height right; mill out the axleboxes to allow the bearings to move freely. Brake gear is not included with the axleguards, but there's a separate BB product for RCH-style gear that is very good.

Bill's wagon kits with integral suspension work on the same principle, but set the wheelbase for you and I think the buffer height comes out right by default; brake gear is included. These axleguards are nearer to scale spacing across the wagon, so you need specially-deep bearings.

The Rumney Models wagon-chassis set the wheelbase and the ride height and include fine brake-gear. (Disclaimer: haven't built any of these; not my period.)

The Exactoscale chassis (from C&L) set the wheelbase but you have to pack for buffer height yourself. With these kits, you pretty much have to use Exactoscale's wheels running in Exactoscale's parallel (not pin-point) bearings; in return, you get a low-profile bearing that needs only a small cavity in the axlebox to move freely. Exactoscale brake-gear is a pig to assemble if you have brakes on only one side of the wagon; probably OK for more modern vehicles with brakes both sides.

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Flymo748
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Re: Ideal starter wagon chassis?

Postby Flymo748 » Mon Jul 06, 2015 5:14 pm

It's amazing how quickly we can lose sight of the original question...

The first post on the thread asked for some suggestions "FOR A BEGINNER". The thread title is even "Ideal STARTER wagon chassis"!

Superb though both Bill's and Justin's wagon chassis look when made up, from what I've seen of them they hardly fit the brief of a simple sprung chassis to enable testing of trackwork.

My 2p would be with the original response of a pair of Bill Bedford's sprung w-irons, *and* a Brassmasters wheelbase jig (the fold-up U-shaped one) to make sure that the two axles are parallel. Without that, it fails on the primary purpose of testing track.

I'd use them on a simple plastic wagon kit - say a Parkside covered van so that you can turn the floor over and have a flat surface to mount the w-irons on, and go from there.

Using the wire provided in the kit has always given me a reasonably correct buffer height without specific packing involved. Always remember that the prototype didn't have a consistent height depending on whether the vehicle was loaded or not.

If there's one thing that we as P4 modellers are *very* good at, it's encouraging new modellers to run at sprint pace when they are only just learning to walk. Closely followed by thinking that we know the answer, even if it wasn't to the question that was actually asked!

Rant over, now let's get back to some sensible advice and maybe some pictures or voices of examples!
Cheers
Flymo
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MikeH
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Re: Ideal starter wagon chassis?

Postby MikeH » Mon Jul 06, 2015 6:19 pm

Thanks all, Well iv'e been trying to figure out what I need to buy and where, Wow there is so much odd bits and bobs all over the place. This P4 malarky isn't as easy to get into as I first thought lol.

Ok so far I have in my basket @wizard models is:

1*
Standard waisted brass pinpoint bearings
Made by:Markits [BPP002]
Scale:4mm:1ft; (1:76) OO, P4 & EM Gauges
40 items in packet.

£2.08
20%
£2.08
£0.42
2*
RCH wagon W irons with springing, 1923 pattern
Made by:Bill Bedford [BWF002/4]
Scale:4mm:1ft; (1:76) OO, P4 & EM Gauges
6 items in packet.

Now I still need to get the jig that Flymo suggested from brassmasters, I have some Alan Gibson wheels too. I'm thinking I don't need no1 unless I fit basted axleboxes though and they fit into them with abit of drilling? So I think im finally getting somewhere here or going horribly wrong lol

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jim s-w
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Re: Ideal starter wagon chassis?

Postby jim s-w » Mon Jul 06, 2015 7:05 pm

As I mentioned to Mike via a pm. If you are testing track you don't want a sprung chassis a all. You want a long wheelbase rigid chassis that will show up the defects in the track. A sprung chassis will hide them because it is, after all, what it's designed to do.

Cheers

Jim

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grovenor-2685
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Re: Ideal starter wagon chassis?

Postby grovenor-2685 » Mon Jul 06, 2015 8:12 pm

Now I still need to get the jig that Flymo suggested from brassmasters, I have some Alan Gibson wheels too. I'm thinking I don't need no1 unless I fit basted axleboxes though and they fit into them with abit of drilling? So I think im finally getting somewhere here or going horribly wrong lol

You have completely lost me with "basted axleboxes", but if you use *2 (Bill Bedford W irons) then you most definitely need *1 (waisted bearings). The axleboxes are optional, the vehicle will run without and they can be added later, but without the bearings the springs don't work.

At this point I would also take note of Jim and just replace wheelsets in a simple RTR wagon, one rigid and one sprung will give your track a good test and allow you to learn the difference.
Regards
Regards
Keith
Grovenor Sidings

MikeH
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Re: Ideal starter wagon chassis?

Postby MikeH » Mon Jul 06, 2015 8:40 pm

Yeah I replied to Jim's pm earlier, I decided I would do a long wheelbase rigid conversion with a straight wheel swap, but also attempt to make one sprung to see what's involved before I get to far ahead of myself. As for Basted, I can't remember what that was supposed to say! Righto I will get the bearings too!

Cheers

DougN
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Re: Ideal starter wagon chassis?

Postby DougN » Mon Jul 06, 2015 9:57 pm

I think I know... It is an apple spell checker.... Wasted could easily become basted. Having just typed this lot on an iPad does suggest this! Yes yes we know it should be waisted.
Doug
Still not doing enough modelling

dclift
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Re: Ideal starter wagon chassis?

Postby dclift » Mon Jul 06, 2015 11:51 pm

Over the last two years I have built a number of ancient Cambrian wagon kits (purchased when Walker and Holzapfel were having their closing down sale about thirty years ago) with Bill Bedford's excellent springing units and also converted several rtr wagons. I use the Brassmasters axle spacing jig to set the wheelbase, but I then put the wagon onto a flat surface and give it a gentle shove. Obviously it should run freely but it should also run in an absolutely straight line. If it doesn't, the axles are not parallel to one another and need to be adjusted accordingly. This non-parallelism can occur if the axles were not a reasonably snug fit in the slots in the spacing jig and will be an impediment to good running.

Good luck, Mike, with your first efforts in P4. It is worth the effort involved.

David Clift.
David Clift.

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Paul Townsend
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Re: Ideal starter wagon chassis?

Postby Paul Townsend » Tue Jul 07, 2015 5:26 am

dclift wrote: put the wagon onto a flat surface and give it a gentle shove.

David Clift.


That tip is brilliant, many thanks.

In 40+ years of P4 modelling I don't recall seeing or hearing it before so I just tried it with a naughty wagon on plate glass...RESULT!

I have certainly used the old plate glass test as a static check for rocking and squareness...eg on old OO rigid chassis or new P4 short wheelbase rigid bogies.
It never occurred to me to do the rolling bit.

Winander
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Re: Ideal starter wagon chassis?

Postby Winander » Tue Jul 07, 2015 11:42 am

jim s-w wrote:As I mentioned to Mike via a pm. If you are testing track you don't want a sprung chassis a all. You want a long wheelbase rigid chassis that will show up the defects in the track. A sprung chassis will hide them because it is, after all, what it's designed to do.
Jim


This thread is certainly producing some gems. Exactly how long a wagon is a long wagon? The reason I ask is that it will probably be redundant for my chosen prototype so I could knock together a dummy vehicle.

thanks in advance and thanks to jim s-w and David Clift for the tips!
Richard Hodgson

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Guy Rixon
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Re: Ideal starter wagon chassis?

Postby Guy Rixon » Tue Jul 07, 2015 11:54 am

Flymo748 wrote:It's amazing how quickly we can lose sight of the original question...

The first post on the thread asked for some suggestions "FOR A BEGINNER". The thread title is even "Ideal STARTER wagon chassis"!

Superb though both Bill's and Justin's wagon chassis look when made up, from what I've seen of them they hardly fit the brief of a simple sprung chassis to enable testing of trackwork.

My 2p would be with the original response of a pair of Bill Bedford's sprung w-irons, *and* a Brassmasters wheelbase jig (the fold-up U-shaped one) to make sure that the two axles are parallel. Without that, it fails on the primary purpose of testing track.

I'd use them on a simple plastic wagon kit - say a Parkside covered van so that you can turn the floor over and have a flat surface to mount the w-irons on, and go from there.

Using the wire provided in the kit has always given me a reasonably correct buffer height without specific packing involved. Always remember that the prototype didn't have a consistent height depending on whether the vehicle was loaded or not.

If there's one thing that we as P4 modellers are *very* good at, it's encouraging new modellers to run at sprint pace when they are only just learning to walk. Closely followed by thinking that we know the answer, even if it wasn't to the question that was actually asked!

Rant over, now let's get back to some sensible advice and maybe some pictures or voices of examples!
Cheers
Flymo


I think you're conflating "simple" with "easy". Bill's separate axleguards are very simple but not especially easy, because they only fix one of the critical dimensions for you. There's a knack to using them - the Brassmasters gauge is part of that. The other products I mentioned are not simple, but are possibly easier because they constrain more dimensions.

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Guy Rixon
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Re: Ideal starter wagon chassis?

Postby Guy Rixon » Tue Jul 07, 2015 1:16 pm

Suggestions for using Bill Bedford's axleguards, hopefully avoiding one's first couple of wagons being non-runners (like mine were).

1. Use the Brassmasters axle-spacing jig as suggested above; it's very good. And the "does it curve by itself when rolling freely" test, above, is a great idea.

2. Make up the axleguards into a rolling chassis separate from the decorative part of the wagon, so that you can fettle the suspension without the solebars, headstocks and brakes getting in the way. Either solder the axleguards to a flat plate, which becomes a false floor to the wagon, or join them with a wire, as shown in other posts in this forum: http://www.scalefour.org/forum/viewtopic.php?f=120&t=4205.

3. To get full suspension travel, the top of the bearing carrier has to pass into the little slot in the horizontal part of the axleguard, so make sure that this is not blocked by your false floor or packing.

4. Always use "waisted" bearings for the axles as this reduces the size of the holes needed for bearing movement inside the axleboxes.

5. File the pip off the top of each axle bearing to further reduce the space needed in the axlebox. If you file down too much you'll break through into the tip of the internal cone and have a pinhole. Therefore, best to do this before putting the bearings into the bearing carriers so you can easily discard the ones with the holes.

6. Be careful when fitting the suspension wire to the bearing carriers. You need to bend the tabs on the carriers slightly, but you need to do it below the half-etched slot. If you bend them at the slot they might break. There is a post on this forum somewhere from Bill himself detailing this but I can't can't find it in search.

7. The axleguards must be parallel, or the suspension may jam. If fitting the wheels splays them outwards, it probably means that the bearing carriers aren't seating cleanly into the axleguards. You can sort this out easily enough with a file, and it's easier to do this before you put the axleguards into the wagon, hence the separate-chassis idea.

8. If there's a lot of end-float on the axles then your bearings are likely deeper than the average (e.g. Markits bearings have deeper coning, as advised elsewhere on this forum by Keith) and you may need to move them within the bearing carriers. BB axleguards sold separately (c.f. the chassis in the BB complete kits) have a spacing that works with typical (e.g. Gibson) bearings and don't need the deeper kind. See elsewhere in this forum for more discussion and gauge that tells you which depth of bearings you have. http://www.scalefour.org/forum/viewtopic.php?f=23&t=4033&p=35883&hilit=bearing+depth#p35883

9. Make sure that the suspension moves freely before putting the rolling chassis into the wagon....

10. ...and if it then jams up when in the wagon it'll be because the cavities in the axleboxes are not quite big enough. Easy enough to take out the rolling chassis and fettle the axleboxes, but clearly one shouldn't fix the chassis into the wagon until completely sure of this step.

10. If retaining the plastic brake parts from a RTR wagon or a kit, be prepared for the brakes to drag if they were moulded for a slightly-different wheelbase than that set by your wheelbase gauge. If so, you should be able to grind enough off the shoes to get clearance. This will be easier if done before fixing the axleguards.

11. Expect to pack the axleguard + false floor assembly away from the floor of the wagon somewhat to get the buffer height right. The buffer-height gauge sold in the Society stores is useful here.

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Tim V
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Re: Ideal starter wagon chassis?

Postby Tim V » Tue Jul 07, 2015 3:09 pm

I have something like a hundred wagons. None of them has been built from a sprung chassis kit!

OK I'm not a beginner, but such a kit is not a prerequisite to building track.
Tim V
Scalefour News Editor

MikeH
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Re: Ideal starter wagon chassis?

Postby MikeH » Tue Jul 07, 2015 4:44 pm

Thanks everyone for all your helpful responses and thanks Guy for that informative things to do/look out for, Very useful information indeed. Now just to wait for the postman :) I'm about to order the jig from brassmasters, is there anything else worth getting from there while I'm at it?

Cheers

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Guy Rixon
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Re: Ideal starter wagon chassis?

Postby Guy Rixon » Tue Jul 07, 2015 8:55 pm

Perhaps the buffer-height gauge?

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Will L
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Re: Ideal starter wagon chassis?

Postby Will L » Tue Jul 07, 2015 9:21 pm

Tim V wrote:I have something like a hundred wagons. None of them has been built from a sprung chassis kit!


But the a fair chunk of those would have pre-dated the current generation of sprung wagon suspension kits wouldn't they. I certainly agree that once you have a way of doing things that works, you're not likely to want to change, but if you started now??

The last 4 wagons I produced (and this was a few years ago) I did 4 otherwise identical GER 5 plank opens, with 3 different springing systems (Bill Bedford, Masokits and home grown) and one compensated, just to see which worked best. I did them over a week end so I can't say they complicated the build that much. My home grown effort I wont be repeating, but they all ran quite well enough. There was a 5th which pre-dated them by some years. It had been built 00 and rigid. With a wheel transplant even that ran acceptably and only really showed up when we tried them at speed over complex point work.

billbedford
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Re: Ideal starter wagon chassis?

Postby billbedford » Wed Jul 08, 2015 8:27 am

While the Brassmasters axle jig is useful for checking a finished wagon, the Bill Bedford jig was designed to be used in construction and as such allows easy access to the base plate of the w-iron. These are available as BBE021-4 from Eileens. Note that the sketch on the website shows an earlier version. The current version is like this:

E021 v.2 w-iron jig.png
Bill Bedford
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MikeH
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Re: Ideal starter wagon chassis?

Postby MikeH » Wed Jul 08, 2015 6:32 pm

billbedford wrote:While the Brassmasters axle jig is useful for checking a finished wagon, the Bill Bedford jig was designed to be used in construction and as such allows easy access to the base plate of the w-iron. These are available as BBE021-4 from Eileens. Note that the sketch on the website shows an earlier version. The current version is like this:

E021 v.2 w-iron jig.png


Ok awesome, Thanks! Eileens is a little easier to order from and im not building a finished wagon so that will do for now.

Cheers

MikeH
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Re: Ideal starter wagon chassis?

Postby MikeH » Sat Jul 11, 2015 11:05 am

Well things had arrived, I put together the buffer height and axle jig. I started to put the w-irons together and that's where things wen't a little pear shaped. I got the parts together but the wire kept falling out of the holes at the end of the etch and trying to get wheels and bearings into both ends without things falling out was nigh on impossible so I think I must be doing something wrong.. anyway I will do a little more research and see what I find.

On the plus side, I managed to do a straight wheel swap on a oo wagon in seconds and it runs on my "test" track

dal-t
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Re: Ideal starter wagon chassis?

Postby dal-t » Sat Jul 11, 2015 11:43 am

MikeH wrote:I got the parts together but the wire kept falling out of the holes at the end of the etch and trying to get wheels and bearings into both ends without things falling out was nigh on impossible so I think I must be doing something wrong..


Not necessarily - it is one of those 'have to believe it will happen' things (like getting the bolts for a starter motor to take up while lying on a concrete garage floor in the middle of January!). But the most useful tip I was given before building my first sprung underframe was to file a groove in the bottom of the bearing face to make it easier to get the pin-point into the bearing. Other than that it comes down (for me) to working out how to get gravity to help rather than hinder (i.e. stop the bearing carriers flopping down before the axle is there to hold them in place). Once one end/axle is done it should be safe and shouldn't affect the other end - if it does, then maybe you are doing something wrong?
David L-T

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Guy Rixon
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Re: Ideal starter wagon chassis?

Postby Guy Rixon » Sat Jul 11, 2015 1:51 pm

MikeH wrote:...but the wire kept falling out of the holes at the end of the etch and trying to get wheels and bearings into both ends without things falling out was nigh on impossible so I think I must be doing something wrong...


Happens to me too; I don't think you're doing anything wrong per se.

If you assemble the rolling chassis outside the wagon, you can leave the tails of the spring wire sticking out by at least 5mm, preferably more, from the edges of the axleguards and this reduces the chances of it falling out. You only need to trim it in final assembly where it fouls something, like the headstocks, the buffer tails or the brake hangers.

If you run out of wire when doing the last pair of axleguards in the pack (unlikely, there's a good supply in each pack), you can get more from Eileen's or buy it locally as guitar strings.

To restrain the spring carriers against the axleguards, when putting in the wheels, I use the little aluminium "soldering clips" that were originally designed as hair clips. Self-grip tweezers also work.

MikeH
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Re: Ideal starter wagon chassis?

Postby MikeH » Sat Jul 11, 2015 2:22 pm

Thanks, Sounds like i'm doing it right then, just highly fiddley. I had an idea of using a little blu-tack to hold things together so I will give that a go tomorrow

Cheers

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Guy Rixon
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Re: Ideal starter wagon chassis?

Postby Guy Rixon » Sat Jul 11, 2015 2:49 pm

Blu-tac will be fine provided that you can remove it all afterwards. Anything left may stop the suspension from sliding freely.

A few vehicles ago, I was painting one with BB axleguards already fitted and not removable. (These days I use Carr's blackening solution on the brass and leave out the paint.) I wanted to keep the paint off the sliding surfaces, so I masked up with rubber masking fluid, sprayed primer and then, a day later, spayed black enamel. I was then restrained from even looking at the work while the Four Horsemen ran a gymkhana through my life. Two weeks later, I came back to the model, sitting in full sun on the bench where I'd left it. The rubber stuff had melted and run over everything, then apparently mutated like something out of the Alien movies. The rubber/paint/ick mixture would not shift out of the crevices cleanly, paint that I wanted to keep was abandoning ship all over, and the suspension wouldn't go because the "protected" sliding surfaces were clagged up. I ended up stripping the whole model with Nitromors.


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