Dettingen GCR might have been layout

[richard i]

Hi Richard

 

If screwed up as designed I don't think you need to add the complication of soldering them. It would be a blighter to get off should you need to. The old style Romford crank pin washers are soldered because there is no other way of keeping them on.

Thanks for getting back on this Spider. In response...

Yes......but I don't want them to start unthreading themselves once fitted as they will be a blighter to get back on again. I feel the axel needs gluing/ soldering to stop the rotation.

Richard

[Regularity]

You could lock the screw in place by putting a dab of nail varnish on it. This forms a bond which you can break if needs be by gripping the crankpin in a pair of pliers, or by dissolving the bond with acetone (nail varnish remover).

I’ll be honest: I haven’t tried this on crankpins in outside framed cranks, but I have found it to be very successful at locking crankpin nuts in place on Gibson and Sharman wheels in the past.

[richard i]

You could lock the screw in place by putting a dab of nail varnish on it. This forms a bond which you can break if needs be by gripping the crankpin in a pair of pliers, or by dissolving the bond with acetone (nail varnish remover).

I’ll be honest: I haven’t tried this on crankpins in outside framed cranks, but I have found it to be very successful at locking crankpin nuts in place on Gibson and Sharman wheels in the past.

Now where does the wife keep her nail varnish in her cabinet of mysterious things.

[Caley Jim]

Or you could use loctite.

 

Jim

[richard i]

Never seen loctite on sale near me. Have heard it much mentioned I should keep looking.

[billbedford]

Now where does the wife keep her nail varnish in her cabinet of mysterious things.

 

 

Any paint or vanish would do on small bolts.

[billbedford]

Never seen loctite on sale near me. Have heard it much mentioned I should keep looking.

 

Look in your local Auto-store for thread-lock or nut-local retainers. Standard loctite is overkill on threads of this size.

Edited June 2, 2018 by billbedford

[richard i]

Look in your local Auto-store for thread-lock or nut-local retainers. Standard loctite is overkill on threads of this size.

Bill as always a mine of useful advice. Your post has prompted me I really do need to work out that gcr Robinson mainline set of five coaches and get the order into you. Now the academic year is done I will have more time to work it out.

Richard

[richard i]

I have spent some time puzzling over this. How to get the coupling rods running smoothly.

I think I have the plan.

Rig up the outside cranks, use the coupling rods to ensure spacing is correct. Introduce solder to the cranks. Remove coupling rods. File back/ cut excess extended axel. Fit coupling rods then crank pins.

Rinse and repeat on the other side at 90 degree rotation.

Unless someone can see an issue with this approach.

Richard

[Clive Mortimore]

I have spent some time puzzling over this. How to get the coupling rods running smoothly.

I think I have the plan.

IMG_5870.JPG

Rig up the outside cranks, use the coupling rods to ensure spacing is correct. Introduce solder to the cranks. Remove coupling rods. File back/ cut excess extended axel. Fit coupling rods then crank pins.

Rinse and repeat on the other side at 90 degree rotation.

Unless someone can see an issue with this approach.

Richard

In a Mr Punch voice  "That's the way to do it"

[richard i]

Slowly trying to get a smooth running chassis.

Just one tight spot to track down.

One day so far.....the saga continues.

[Clive Mortimore]

Hi Richard

 

It is a bit late now but when I do outside framed shunters I line up the outside cranks 180 degrees to the cranks on the wheels I find that easier when making sure they are quatered correctly as I have a reference point on each wheel, the crank. Once the body is on you cannot see the crank on the wheels. 

[richard i]

I tried to line them up over the crank as a guide and had coupling rods in to hold them at the correct distance. More to the point you should be in bed.

[gr.king]

It was an incredibly tiny adjustment to quartering that finally got an LNER J6 that I recently built running exactly as it should.....

 

I check each side of the loco separately, with one crank held rigidly in the exact "six o'clock" position. The other crank should have exactly equal small amounts of slop either side of the true six o'clock position. If the slop is unequal, either the rods don't match the length of wheelbase, or (if you've already proven that the rods do match the wheelbase) the quartering (of the cranks in this case) is a shade out.

[Caley Jim]

I check each side of the loco separately, with one crank held rigidly in the exact "six o'clock" position. The other crank should have exactly equal small amounts of slop either side of the true six o'clock position.

With one set of cranks in the 6-o'clock position, the opposite side should be at either 9-o'clock or 3-o'clock. I.

E. the cranks on opposite sides should be at 90 degrees to one another, hence 'quartered'. If they are both at 6-o'clock you'll never get good running, if it runs at all.

 

And yes, a tiny adjustment to the quartering can make a huge difference to the running.

 

Jim

Edited June 8, 2018 by Caley Jim

[richard i]

With one set of cranks in the 6-o'clock position, the opposite side should be at either 9-o'clock or 3-o'clock. I.

E. the cranks on opposite sides should be at 90 degrees to one another, hence 'quartered'. If they are both at 6-o'clock you'll never get good running, if it runs at all.

And yes, a tiny adjustment to the quartering can make a huge difference to the running.

Jim

Cranks are set at 90 degrees so one trap I did not fall into. Though, if I had that would be a simple one to solve.

[gr.king]

I'd assumed that the term "quartering" was well understood as meaning that the cranks are at 90 degrees on opposite sides.

[Regularity]

It’s not so much for the wheels - anything other than close to 0 or 180 degrees suffices to get them going the same way - as the pistons in the cylinders. If theses are working on the same stroke, then if they are both at top or bottom of the stroke, you have no control over which way the wheels will turn.

90 degrees provides for the most regular power output with two double-acting cylinders.

[gr.king]

Consideration of what the pistons would be doing in a real locomotive is of little or no relevance in an electrically axle-driven model without any pistons. In this case it is very much the disposition of the cranks and the dimensions of the rods that determine the smoothness and consistency of operation, and when the cranks on opposite sides are as nearly as possible at 90 degrees to one another there is the greatest chance of equally smooth running in both directions even when unavoidable (but very small) discrepancies in dimensions creep in. The 90 degree setting ensures that the rod on one side is exerting maximal "matching" effect on the motion of the two wheel sets even when the rod on the other side is at horizontal dead-centres and is doing nothing to match up the rotation of the two wheel sets.

[Caley Jim]

I'd assumed that the term "quartering" was well understood as meaning that the cranks are at 90 degrees on opposite sides.

My apologies to you. I read your original post as suggesting that the wheels on either side should be at 6 o'clock. On re-reading now I see that you were referring to the wheels on the same side.

 

Jim

[richard i]

My apologies to you. I read your original post as suggesting that the wheels on either side should be at 6 o'clock. On re-reading now I see that you were referring to the wheels on the same side.

Jim

Jim

Not a problem, as I plough a lone path here I appreciate any and every suggestion as it can be something I have missed. Something which is obvious to the writer but which until you are told about it is missed. TW told me about quartering when he showed me how to build my first loco aged 25. Until then I had no idea, but then had never seen both sides of the same loco at the same time. That was the benefit of being in a club, however there are none around here.

Richard

[richard i]

Long time absence.

Gcr 12at paused whilst access to soldering iron time is limited.

Looking at my silver jubilee rake. Can work out all the transfers except the smaller silver jubilee written in blue with no backing. Five rows from the bottom.

Can anyone help? Where does it go on the train?

Richard

[Clive Mortimore]

Long time absence.

Gcr 12at paused whilst access to soldering iron time is limited.

Looking at my silver jubilee rake. Can work out all the transfers except the smaller silver jubilee written in blue with no backing. Five rows from the bottom.

AFEF2505-1D61-462C-B1AD-030ACE9CDC2C.jpeg

Can anyone help? Where does it go on the train?

Richard

On the rear gangway cover.

[richard i]

I have a back board for the train already. So it must be a spare.

Thank

Richard

[richard i]

Little to report, except I broke a rod in trying to sort an issue with the running.

Grrrrrrrrrr.

So I had to start again.

Maybe this will work better once finished.

First modeling in a while. This does not bode well.

Richard