AMS COACH REPAIR Ideas
- Thread starter nico
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johnsaintjim
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What's the other side of the broken boss nico? I would look to screw through from the other side into the broken portion of you can. Even if it's the platform on the end of the coach, you may find a countersunk head self tapper would do. Better, if you have a tap, you could use a proper bolt into the broken-off section.
nico said:I have two AMS coaches with one coupler mount broken of each and i am in need of your advice on how to repair them
heres a few pics of one of the coaches damage,they both have the same damage .the first pic is what it should look like
. . .
The pix are a great help in understanding the problem.
Since you have two damaged coaches, this may be a situation that is likely to occur again. A common design principle is to have a deliberate easily / cheaply replaced weak link to prevent damage to other components. Rather than reinforcing the coupler mountings it may be better to have something like a magnetic mount that will come loose if there is excessive load on the coupler. Of course this all depends on what loads the couplers are likely to see in service, both in tension and compression and the cause of the initial damage.
I claim top marks for an **** solution! 100% factually accurate, but no practical help whatsoever!
Depending on your prejudices, replace **** with accountant / IT / engineering / management / whatever!
nico
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don9GLC2 said:nico said:I have two AMS coaches with one coupler mount broken of each and i am in need of your advice on how to repair them
heres a few pics of one of the coaches damage,they both have the same damage .the first pic is what it should look like
. . .
The pix are a great help in understanding the problem.
Since you have two damaged coaches, this may be a situation that is likely to occur again. A common design principle is to have a deliberate easily / cheaply replaced weak link to prevent damage to other components. Rather than reinforcing the coupler mountings it may be better to have something like a magnetic mount that will come loose if there is excessive load on the coupler. Of course this all depends on what loads the couplers are likely to see in service, both in tension and compression and the cause of the initial damage.
I claim top marks for an **** solution! 100% factually accurate, but no practical help whatsoever!
Depending on your prejudices, replace **** with accountant / IT / engineering / management / whatever!
damage was caused by courier not handling parcel correctly
What I would do.....
Remove the broken bit of "stem" from the car and from the part still attached to the coupler box. Sand/file smooth.
Cut a pad/pads of styrene that would build up a "block" that would fill the entire gap, and put these in with a weld type styrene glue (with some testing to make sure it is not too agressive to the plastic of the car).
Once this has dried for a good long while.....
Drill a hole for the mounting screw in the new pad.
There have been other complaints about these breaking in service from memory?
Remove the broken bit of "stem" from the car and from the part still attached to the coupler box. Sand/file smooth.
Cut a pad/pads of styrene that would build up a "block" that would fill the entire gap, and put these in with a weld type styrene glue (with some testing to make sure it is not too agressive to the plastic of the car).
Once this has dried for a good long while.....
Drill a hole for the mounting screw in the new pad.
There have been other complaints about these breaking in service from memory?
johnsaintjim
Registered
nico said:johnsaintjim said:
here is the other side
Nico I'll stick with my recommendation of screwing through from the top. It looks like all the train forces go through this boss and having already boken off, I doubt if glue will hold it. However, I have no intention of falling out with anyone over this.
Assuming you're not going to let the courier play with your coaches!
Any coupler drawbar load acts through a lever on the boss where it attaches to the underside of the coach. This will put considerable load on the boss, just where it has already broken. While drilling and pinning or even screwing will retain the coupler in place without load you still have the problem of 'drawbar load' on the boss. I would be tempted to consider reinforcing the boss by cutting a block (wood, plastic or some other convenient material) to fit snugly between the vertical sections on either side, with a (tight) clearance hole for the boss. With liberal amounts of adhesive and perhaps also the pin / screw reinforcement.
You could also consider removing the boss flush with the underside and fitting the coupler direct to a new shaped block, glued in place.
My experience with repaired plastic bosses is poor, hence the suggestion for an additional block.
Any coupler drawbar load acts through a lever on the boss where it attaches to the underside of the coach. This will put considerable load on the boss, just where it has already broken. While drilling and pinning or even screwing will retain the coupler in place without load you still have the problem of 'drawbar load' on the boss. I would be tempted to consider reinforcing the boss by cutting a block (wood, plastic or some other convenient material) to fit snugly between the vertical sections on either side, with a (tight) clearance hole for the boss. With liberal amounts of adhesive and perhaps also the pin / screw reinforcement.
You could also consider removing the boss flush with the underside and fitting the coupler direct to a new shaped block, glued in place.
My experience with repaired plastic bosses is poor, hence the suggestion for an additional block.
johnsaintjim
Registered
don9GLC2 said:
Yes, I agree, the block glued to the sides as described above would be a belt and braces answer which would certainly fix it for good.
From what we can see here, the design is a bit flimsy. Seems like all of us in our own way have found couplings needing to be robust due to the whole weight of the train going through them. I must say I haven't had any broken ones since building my vehicles for the garden but then I haven't had a courier drop them off the back of his van either.
Rhinochugger
Retired Oik
nico said:like this?
what type of glue would be strong enough,itake it super glue wouldnt work
You could reinforce it by inserting a small brass rod as a dowel either side, drilled through the green plastic
Rhinochugger
Retired Oik
Maybe a two part epoxy, preferably one that is thick in consistency, then it will fill any slight gaps ? :thinking:nico said:like this?
what type of glue would be strong enough,itake it super glue wouldnt work
Probably a quick acting one
johnsaintjim
Registered
nico said:like this?
what type of glue would be strong enough,itake it super glue wouldnt work
Yes, I would Araldite it because that will take up any gaps. As Don above mentioned, probably best to take the remains of the boss out altogether if you can so you can glue the block on four sides. Best make sure the block material is man enough to take the screws and not split.
Oh and may I welcome the Irish dancer back. Wonderful.
johnsaintjim
Registered
nico said:
Err yes, good idea.
I must say I thought it was a bit strange for a man who could build a railway like yours not to have a few ideas about how to fix the broken coupling...
Rhinochugger
Retired Oik
nico said:
Anything that aids the homogenous strength of the fitting - you're only going to get one decent crack at it, so it's better to over design - at least it's not going to be seen.
Alternatively, something like Tufnol for the block (but I never have anything like that when I need it).
Hardwood, or an offcut of solid plastic - if you've been doing any model butchery lately.
I guess you'll get more carriages, and the couplers have to work hard with heavy weights.
Rhinochugger
Retired Oik
I thought that's what we're trying to avoidnico said:Rhinochugger said:Maybe a two part epoxy, preferably one that is thick in consistency, then it will fill any slight gaps ? :thinking:nico said:like this?
what type of glue would be strong enough,itake it super glue wouldnt work
Probably a quick acting one
SNAP
