Suppliers of Delrin Chain?

Rob Pulham

Western Thunderer
Hi All,
In amongst other kits that I am slowly gathering bits and pieces for, I have a Meteor Sentinel Shunter which will be finished as one of the LNER Y3's
The instructions suggest 2'8" Diesel wheels from Roxey and Delrin sprockets/chain from Kalgarin (who don't seems to have any at the moment).
I managed to get some of the recommended 10 tooth sprockets from On the Wagon (EMKDE/Welcome Wagons) but they don't seem to stock chain to suit.

Never having used it before, the next question is how do you work out how much you need/what lengths does it come in?

Thanks in advance for any assistance you can offer.
 

Rob Pulham

Western Thunderer
Just had a look on the Easybuild site and it looks like I will have to wait a bit longer as it seems to be temporarily unavailable from there too:(
 

ZiderHead

Western Thunderer
A friend who's into robots told me that all this delrin chain comes from just one factory and the tooling is worn out, hence the supply problem. Rumour has it they will be retooling and restarting production soon ... but that is just hearsay.
 

Ressaldar

Western Thunderer
Hi Rob,

JLTRT are saying out of stock, PRMRP are still listing - but no stock comment, Slaters don't mention it at all. Suggest that you try an American source?

Best of luck.

cheers

Mike
 

Steph Dale

Western Thunderer
A friend who's into robots told me that all this delrin chain comes from just one factory and the tooling is worn out, hence the supply problem. Rumour has it they will be retooling and restarting production soon ... but that is just hearsay.

Not hearsay, unfortunately; I've heard the same from others in the trade. Some patience may be required...

Steph
 

decauville1126

Active Member
You might also try Karlgarin Models - I've bought from them in the past ok.

An email to Brian Osborne at Branchlines enables him to send you pdf catalogues of their stuff and I'm sure he can also advise if he has any stock.

I've also seen various sellers on ebay with it.
 

Stevesopwith

Western Thunderer
I'll try to answer the second part of your original question......it's usually sold by the inch, or in arbitrary lengths, eg 6". The link pitch is 1/8th" as close as I can measure, so twice the wheelbase in 1/8ths plus 10 more links for the sprockets will give you a good idea as to how many you need. It's not quite that simple when the wheelbase doesn't work out in units of 1/8th", ( It almost certainly won't ) .
This system is very tolerant, too much sag is a bit unsightly rather than an operational issue. However, even moderate tightness may cause binding problems from minor sprocket eccentricty or local tight spots on the chain.

Once you've worked out a possible number of links, it's worth making up a chain, along with the sprockets to compare the resulting axle spacing with your drawing or frames. This will show the likely slack . Depending on the exact circumstances of the kit chassis, it's worth remembering that Sentinels were built with provision to adjust the axle positions to take up slack, so it would not be improper to move one axle to a better position. Otherwise you need some form of 'slack controlling device' .... rather than a chain tensioner...( you don't want 'tension' )

In the past I've thought up all sorts of elaborate systems with rollers and sprung swinging arms..... ( I used to restore old motor-cycles )... but honestly, a simple curved strip of brass, with a bracket allowing height adjustment is absolutely fine. Add a smear of gear grease if you like, but it tends to collect dust.

The system works equally well with sprung or compensated axles, and I've not had any problems arising from the chain and sprockets being well off centre. I have had great difficulty trying to join up the two ends when the axles are already in the chassis.... it's a fiddly job at the best of times, and there isn't the space or the slack you need if it's all up together..... so I'd strongly recommend removable axles.

Finally... to be really nerdy... most of the Sentinels I've studied have their chains on the left side... a fact I discovered after I'd put Fry's chain on the right. :(


WTC No6 4mm c.jpg


Frys Sentinel Chassis 2.jpg
 

Rob Pulham

Western Thunderer
You might also try Karlgarin Models - I've bought from them in the past ok.

An email to Brian Osborne at Branchlines enables him to send you pdf catalogues of their stuff and I'm sure he can also advise if he has any stock.

I've also seen various sellers on ebay with it.

Thanks, sadly they all seem to be out at the moment (I haven't tried Branchlines yet).
 

Rob Pulham

Western Thunderer
Thanks Steve,

You can be as nerdy as you like when offering advice based on research and experience:thumbs: . The left hand side it shall be:)
 

Dog Star

Western Thunderer
... I have had great difficulty trying to join up the two ends when the axles are already in the chassis.... it's a fiddly job at the best of times, and there isn't the space or the slack you need if it's all up together..... so I'd strongly recommend removable axles.

I have been thinking about using the ABC diesel motor unit for some JLTRT kits and ABC uses Delrin etc. to transfer power from the driven axle to another axle on the same bogie. The moulded bogies have top-hat bearings for the axles and those bearings are inserted into (moulded) holes within the bogie inner frame. Where you have written "I'd strongly recommend removable axles", after looking at your photo I suspect that you may have intended "removable sprocket and axle". In the case of the JLTRT diesel bogies the sprocket / axle cannot be removed as a single unit... the sprocket has to be slid along and off of the axle as that axle is slid through the bearings.

What problem, if any, might be encountered with fitting Delrin chain to JLTRT bogies as described here?

regards, Graham
 

Stevesopwith

Western Thunderer
Graham..... you are quite right.... I was thinking of a complete axle assembly, with sprocket and hornblocks. The 7mm Fry has CSBs in High Level blocks, the 4mm Wantage Tram is compensated, but also has removeable bearings.
I'm not familiar with the details of the ABC unit, so I don't know how much 'fitting room' is available, but so long as the chain loop length has been accurately established I assume it could be fitted over the sprockets as the axles are inserted in place. However, lacking confidence in my ability to get everything right first time, I'm not very keen on a system that requires the dismantling of an interference fit to carry out adjustments or modifications.

If you study the Fry sprockets you will see they are not press fitted. For each one, a Branchlines 1/8" collar, with grub screw was soldered to a Markits 1/8" axle bearing. The sprocket was bored to an interference fit over this bearing and a second bearing was forced in from the opposite end to help keep everything in line.

It seems to work, and it allows assembly and fine adjustment of the sprocket on the axle, and so long as at least one wheel per axle is removeable this might make the assembly and fine tuning of the ABC unit a bit easier.

Cheers.... Steve.
 

Dog Star

Western Thunderer
If you study the Fry sprockets you will see they are not press fitted. For each one, a Branchlines 1/8" collar, with grub screw was soldered to a Markits 1/8" axle bearing. The sprocket was bored to an interference fit over this bearing and a second bearing was forced in from the opposite end to help keep everything in line.
Now providing the answer before the question is asked is.... just not fair :rolleyes: .

The bogies for the JLTRT diesel kits use Slater's wheels with 3/16" dia. axles, so what is the next question?

regards, Graham
 

Stevesopwith

Western Thunderer
Hmmmm..... not sure........but the answer might be 3/16" ID collars, ( or turned down grub screwed gear wheels ) plus some bearings from Eileen's Emporium , ( they are 1/4" ED ). I think the 3/16th sprockets will bore out sufficiently, but, of course, first check there's room for such an assembly between the gearbox and the frames


ATB ... Steve.
 

Stevesopwith

Western Thunderer
Graham.......Having done some checking of details of ABC units and my Fry chassis, I'm not sure if my suggestions would fit.

Fry's frames are 28 mm apart, but the high Level Hornblocks take about 3 mm off each side. My Branchlines gearbox is 11 mm wide over it's bushes. To allow space for the collar I had to shorten one side of the sprocket boss. As you can see, it fits, but only just. With narrower frames and wider gearbox there could be problems.

The ABC box is 13.5mm wide. It is suggested that there is sufficient width allowance for ...'plenty of boss to prevent slipping, and to leave room for pinning if needed'. This led me to an alternative suggestion..... fitting a brass bush into each end of the sprocket boss would provide a close sliding fit on the axle, to be locked in place by a taper pin,or a steel screw into a tapped hole in the axle. This would allow easy fitting and removal, and provide a more postive lock. I'm assuming your diesel will have to work a bit harder than Fry.

Rob....I now think the Y3 had a central engine unit and drive shaft, with separate chains connecting to each axle, so my earlier remarks on chain location may not be appropriate in this case. However, I'm not suggesting you copy the full-size arrangement..... :rolleyes:

Cheers..... Steve.
 
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