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Chassis jigs


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I bought two poppy jigs the 0_6_0 version and the lao ger versio i can now get chassis that are square and right first time. Took me about 10 minutes to finish a comet G2 chassis.

 

The 8 axle one works well for industrials (just done a Judith Edge 15" chassis and a 16"chassis in 4mm no problem .

 

I don't need a metal jig..  the price wouldn't be justifiable  and the poppys one works for me!

 

Baz

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Barry

 

The Poppy's jig from all reports is an excellent tool. I can see its fine for tab and slot style chassis and I guess a rigid chassis, but how easy is it to fit hornblocks? if it can ?

 

Where the Hobby Holidays and Avonside jigs come into their own, is for correctly setting hornblocks into the frames, also I received an etched chassis where the bearing holes had been damaged, I was able to repair it very quickly, OK its cheaper to buy a new chassis, than a jig, but given what I have paid (not much more than a Poppy's) for mine and it does both 4mm & 7mm scales, plus a rolling road) I must have built around ten chassis for me and friends, its paid for itself.

 

I have a temperature controlled solder station, its much dearer than a soldering iron. It does the same job but is far more versatile. Well worth the expense, but I use it a lot. These rather more exotic tools are worth it only if they are going to be used. Same as my airbrush and compressor its saved £'s on rattle cans.

 

As I said active clubs with kit builders could buy one for members use (our 0 gauge section has one for this purpose

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No idea regarding hornblocks .. I seem to manage without them. 90% of problems which mean you need compensation seems to be directly linked to the track rather than the chassis. I am using off the shelf  00 track (for speed of building,) laid by an excellent track layer..(LNER 4479).  I do have some beam compensated locos in 00 (and O) which  were built by others. Yes they work possibly better than fixed chassis but not enough for me to fit hornblocks.. I had a hornblock fitted loco (a 4F) . It ran like a wobbly dog and so I put the chassis into the poppy jig and soldered it up solid.. while for others this was heresy I like to have a flat, true chassis.

 

But that is my preference..problem I have is, as an Engineer, you can't actually scale the item Mr Newton spotted.. Gravity .. and scaling Spring Rates acan be tricky too.

 

Baz

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Baz

 

You are very correct in that usually a well built rigid chassis will work well, but on the other hand a well built compensated chassis will have superior conductivity (so we are told). A badly built chassis will work poorly what ever method you use.

 

Again you can use simple cheap jigs like the Comet ones and if well built the chassis will work well

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On 15/07/2020 at 23:02, neilkirby said:

I have a poppy one and despite the fact that I am rubbish at building chassis i do not use this. I found, on mine at least, that the diameter of the axle rods where the coupling rods fit vary in diameter. so to my mind I could not see how they can stay concentric if they are slopping about on some of them when I thought the whole  point of the jig is to keep the axleboxes and coupling rods on exactly the same centres. I questioned this with poppy and they did not think it was a problem. I am certainly no expert, and would love for someone to explain that i am wrong.

regards,

Neil

 

I have never used a jig, and indeed not built a loco kit for some years, but I follow the "Wright Writes" thread on here, where  many loco-builders post, and it would seem Tony Wright swears by the Poppy's Jig.  If it's good enough for him then - when I get around to it once more - it will be good enough for me.  I suggest it may therefore be worth raising the issue on that thread.

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On 12/07/2020 at 06:45, 30368 said:

HI,

 

I have used the 4mm version of the jig for 5 years or more and it seems to do the job well. Chassis and coupling rod alignment is straitforward and I see Poppy now makes a version for eight coupled locomotives too. I would recommend the device.

 

In use for my latest build, DJH A2/3.

1791062671_003(2).JPG.934a00e7d8eef19346cadc56ccdc95a9.JPG

 

Kind regards,

 

Richard B

 

On 15/07/2020 at 23:02, neilkirby said:

I have a poppy one and despite the fact that I am rubbish at building chassis i do not use this. I found, on mine at least, that the diameter of the axle rods where the coupling rods fit vary in diameter. so to my mind I could not see how they can stay concentric if they are slopping about on some of them when I thought the whole  point of the jig is to keep the axleboxes and coupling rods on exactly the same centres. I questioned this with poppy and they did not think it was a problem. I am certainly no expert, and would love for someone to explain that i am wrong.

regards,

Neil

 

Any slop at the outer ends of the jig axles (which look about 4 inches long) will be virtually non-existent at the bearings.

 

I presume the graduations marked on the jig are scale feet?

 

Cheers, Dave.

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On 15/07/2020 at 23:02, neilkirby said:

I have a poppy one and despite the fact that I am rubbish at building chassis i do not use this. I found, on mine at least, that the diameter of the axle rods where the coupling rods fit vary in diameter. so to my mind I could not see how they can stay concentric if they are slopping about on some of them when I thought the whole  point of the jig is to keep the axleboxes and coupling rods on exactly the same centres. I questioned this with poppy and they did not think it was a problem. I am certainly no expert, and would love for someone to explain that i am wrong.

regards,

Neil

 

 

I think you both may be correct

 

Yes the axle rods must be accurately made and the axles must be machined to fit both axles and crankpin holes (there are 2 sizes of crankpin holes)

 

However like everything there are allowable manufacturing tolerances, providing the axle rods are within these tolerances they are fine

 

One would have thought the rods would have been machined to the same specifications

 

If like me you have one of the cheap electronic measuring devices sometimes we expect things to be 100% exact to 100th of a mm when id does not have to be, also the accuracy of these cheap devices needs to be questioned.

 

Perhaps returning the rods for inspection as they could be faulty is the way to go

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I am thinking of Poppy jig

 

I want to handle small 6w such as small Diesel shunters

 

And locos around the size of 4MT

 

But I want to build a couple of 8 coupled some time

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  • 4 weeks later...

I must admit I have been rather dismissive of these contraptions - to me they seem like a solution looking for a problem, but I have been looking at it from the point of view of building a compensated chassis. This or a sprung one will compensate for any minor issues together with track irregularities and the only important thing is making sure the wheelbase matches the coupling rods, which is easily achieved with simple jig axles. It was interesting what was said about the ends having differing diameters as this was certainly the case with the old Perseverance jig axles too but the London Road Models version has tapered ends and works a treat.

 

However thinking back to building rigid chassis in the past it isn't easy to get everything absolutely square, and I suppose this is where they have real value. But all that messing around? Isn't it easier to build it compensated in the first place? :D

 

WP_20180722_16_26_57_Pro.jpg.b0587b4a0f5b06f23e5e4b7dbf7a9fb1.jpg

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Barclay

 

I hear what you say, I built a Perseverance compensated chassis years ago without any jigs and it works fine

 

I tried to build a compensated chassis with Alan Gibson hornblocks and failed

 

I obtained a HH jig s/h and never looked back, I even rescued a wrecked (butchered) Southeastern Finecast chassis using the jig, as you say for non compensated chassis its a real bonus, Soon going to try a set of High Level horn blocks and may attempt to rescue the chassis with the Gibson  hornblocks

 

I guess once you have mastered a method its easy to replicate 

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I’ve used the poppy jig for years now, built over 30 locos with it and it still works all the holes are right no messing and a price I was happy at. 
I did get a second hand avonside jig for the locos what have more driving wheels than a standard 6 arrangement but only used that about twice now. 
poppy is my favourite jig 

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18 hours ago, davidbr said:

I would say the Poppy jig is OK for OO, less so for EM and P4.  It works in the finer standards but requires more care as tolerances are less.  I prefer my Avonside jig, working in P4.

Mine are in regular use for all those three gauges, they have also been used for small 7mm locos on 1/8th axles and 1:48 scale 3'6" gauge. Works perfectly well for anything, I can't see why there should be a distinction there, straight frames and corresponding axle centres and coupling rod centres are necessary in any gauge.

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I've used all three jigs mentioned here, most recently the Avonside one and I've also built compensated chassis with just the Perseverance or Comet jigs (both).

 

I liked the Poppy jig and it is very good value for what it does. I bought it after getting the HH jig a few years before.

 

However, for me, the Avonside jig beats them all hands down. It does a number of things that the others don't do, namely ensuring that all axle holes are precisely lined up (by means of metal components), it ensures that frame spacers are soldered on square and true and makes soldering hornblocks in place an absolute doddle, compared with the Poppy and HH jigs (to say nothing of the Perseverance and Comet ones), because you can solder them on in a flat plane, rather than vertical.

 

You also don't have the annoyance of needing at least three hands to hold both hornblocks in place (on the Poppy and HH jibs), plus insert a large spring, to hold the hornblocks temporarily in place while you solder them on.

 

The Avonside jig allows you to solder the hornblocks on, one side at a time, before you've even soldered both sides of the chassis together.

 

It also allowed me to prove, beyond any doubt, that the problems I'd been having with my 16XX chassis were caused by a faulty pair of Markits driving wheels, rather than anything else that I might have soldered on incorrectly.

 

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2 hours ago, Captain Kernow said:

I've used all three jigs mentioned here, most recently the Avonside one and I've also built compensated chassis with just the Perseverance or Comet jigs (both).

 

I liked the Poppy jig and it is very good value for what it does. I bought it after getting the HH jig a few years before.

 

However, for me, the Avonside jig beats them all hands down. It does a number of things that the others don't do, namely ensuring that all axle holes are precisely lined up (by means of metal components), it ensures that frame spacers are soldered on square and true and makes soldering hornblocks in place an absolute doddle, compared with the Poppy and HH jigs (to say nothing of the Perseverance and Comet ones), because you can solder them on in a flat plane, rather than vertical.

 

You also don't have the annoyance of needing at least three hands to hold both hornblocks in place (on the Poppy and HH jibs), plus insert a large spring, to hold the hornblocks temporarily in place while you solder them on.

 

The Avonside jig allows you to solder the hornblocks on, one side at a time, before you've even soldered both sides of the chassis together.

 

It also allowed me to prove, beyond any doubt, that the problems I'd been having with my 16XX chassis were caused by a faulty pair of Markits driving wheels, rather than anything else that I might have soldered on incorrectly.

 

 

 

My Hobby Holidays jig is set using the coupling rods, then the hornblock axles are screwed tight in place. There is no need for the coupling rods to be kept on the hornblock axles.

 

The HH jig also lets you solder up the axle bearings or hornblocks to each side independently, then both sides are bought together and soldered up. In a very similar to Derek's video using the Avonside jig. Or am I missing something (as usual) ? 

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11 hours ago, hayfield said:

The HH jig also lets you solder up the axle bearings or hornblocks to each side independently, then both sides are bought together and soldered up

Yes, that's possible, but you have to tip the HH jig on it's side and somehow balance it there, whilst soldering at the same time. The Avonside jig, being flat, seems a much more stable platform for this.

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13 hours ago, Captain Kernow said:

but you have to tip the HH jig on it's side and somehow balance it there, whilst soldering at the same time. The Avonside jig, being flat, seems a much more stable platform for this.

 

 As one of the people involved with setting up Avonside Works I have to agree with Tim. I had a HH jig and thought soldering on the flat was preferable to the vertical. This was one of the main features when designing the Avonside Chassis 2 Jig.

 

Robin 

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Never used a jig for any of my (numerous) compensated P4 chassis except for a set of original Perseverance 'jig axles', the coupling rods and a couple of small elastic bands.  Mind you, I've never built anything with more wheels than 6 coupled but I'm sure the same principles would apply, just fit the 'front six' axles and then the 'rear six'.

 

Must get round to that 9F one day.................

Edited by 5050
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4 hours ago, 5050 said:

Never used a jig for any of my (numerous) compensated P4 chassis except for a set of original Perseverance 'jig axles', the coupling rods and a couple of small elastic bands.  Mind you, I've never built anything with more wheels than 6 coupled but I'm sure the same principles would apply, just fit the 'front six' axles and then the 'rear six'.

 

Must get round to that 9F one day.................

 

Jigs are nor essential but they do make life easier. As I posted earlier I obtained an 0-6-0T chassis which someone had butchered, using the chassis I was able to rebuild it.

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Building a square, smooth running chassis has been my biggest issue and one I consistently struggle with. I have a Poppy's jig, used the Comet ones and now have an Avonside jig. I have built around 10 loco's now, but I have only built one chassis with the Avonside so far, and it was easier/better, but still not perfect. It all goes Pete Tong as soon as I hook up the coupling rods/motion gear. 

 

I never know if its the way I built the chassis or if the wheels aren't on the axles properly (I use AG or Markits), or if the coupling rod holes are too big/small etc. They don't always bind straight off either, sometimes running perfectly until I paint and re-assemble, or add motion gear etc. It got so bad once I had to re-build one chassis 3 times, change the wheels and get another set of coupling rods before it would work properly.

 

The other issue is that sometimes they run fine on analogue, but with a DCC chip fitted they struggled to get enough pick up from the track so I end up having to fit pick ups to the tender and sometimes 2 on each wheel which adds to the friction and poor running.

 

I know its down to practice and I know I am just getting one or two basic things wrong, so I don't believe for one minute its any of the jigs that's the issue. I am one of those people that "have all the gear, but no idea"!!!  I am hoping my next attempts will be better (a 4-4-0 and a 2-6-4T)! 

 

 

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  • 1 month later...

Further to my post of July 16th... I have under construction an LNER J38 in P4  from a SE Finecast kit.   Some-one was asking about hornblocks, and this is what I've done.  The first pic shows the chassis in the Poppy jig with brass bearings in the frame axleholes provided, secured with drops of superglue, to get the frames assembled square before adding complications like springing.  Next 2 pics show the chassis before and after cutting out the hornblock spaces (Dremel/disc-cutter, piercing saw), and finally the chassis re-inserted in the jig to enable the Kean-Maygib units to be added.  The actual plastic hornblocks are secured with generous quantities of superglue and held in place while setting with the ubiquitous hair-clips (Pic 4), bent slightly to allow the end sof the jaws to lie parallel when in place round the hornblock.  I'll insert the actual springs in the suspension units after I've painted the frames and before I fit the wheels... to be continued !

 

The additional holes in the Poppy jig I referred to in my earlier post can be seen just to the right of the centre axle in Pic 1, though the J38 wheelbase was such that I didn't need them this time round.

 

Alasdair

J38 Chassis (1) in Jig.jpg

J38 Chassis (2).jpg

J38 Chassis (3).jpg

J38 Chassis (4) in Jig.jpg

Edited by AJCT
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I've used both the hobby holidays & avonside for both 4 & 7mm buildings they are both exceptional pieces of kit. 

When I gave up building for people I sold the hobby holiday 7mm jig on & kept my avonside for my 4mm builds. I still use it to this day having built well over 200 locos on my trusty jig. It's well worth the investment & would reccomend it highly. 

I've never like the idea of wood for a chassis jig as the thought was that holes will loosen in soft material etc.

 

Depends on how many locos you are building & how much you can afford. I went with the buy the best tool for the job you can, I've invested heavily in tools but I was a full time model maker.

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