That's good news Bill, you must be over the moon to finally have it running. The slipping actually reminded me of my Eureka 38. It would slip going up a gradient and I too would remove a carriage one by one. I was doing my head in trying to figure out the problem. In the end I closely watched the wheels while it was travelling up the gradient and found at one point of rotation the middle set of wheels would actually lift of the track causing the front set to slightly lift off the track. It seemed the wheels were out of quart and with a slight adjustment the loco had no trouble hauling the carriages. It might be worth a quick look on your 6030 as it could be an Eureka issue.
Yesterday I decided to do a quick test before I actually started work on 6030. I simply removed all 4 bogies and added a piece of styrene (about 2mm thick x 5mm x 20mm) to the underside of front and rear ends of the boiler, at such a position that the boiler will rest upon the 2 motor units when the units are all clipped together. The 2mm thickness is just right to ensure the footplate of the boiler matches the footplate height of the power units.
So, with a weird-looking 0-8-0 + 0-8-0 now sitting on the track, I coupled it up to the same loaded train that I trialled with 6037 (ie: 18x NOFF concentrate wagons, loaded to about half their physical capacity + Trainorama PHG). The loco was now able to march up the same spiral gradient with the aid of the weight of the boiler resting on the 2 power units.
I'm now reviewing the method of adding the inner bogies. I was going to add a fixed pin (10ba bolt) under the bottom of each power unit, just behind the inner driving axle, to act as a pivot point for a short arm that would bolt to the top of the inner bogie in such a way as to allow it to swivel. That is effectively what I did on 6037 and it works very well.
However, I can't do exactly the same with 6030 as I don't plan (at this stage) to totally replace the clips/plugs that hold the 3 units together. That means that I have to retain the plastic "boxes" that are under the boiler and which perform 2 functions: hold the electrical plugs in place AND are the mounts for the inner bogies. I need to remove any possibility of the boiler weight being borne by the 2 bogies.....
As luck would have it, these "boxes" have a protruding spigot into which the bogie retaining screw is mounted. I now believe the best method might be for me to simply cut-off about half of this spigot and then drill/tap a suitable hole (say M2) so that the inner bogie can still be retained in the right position, BUT will not take any part in supporting the boiler. I will, of course, still need to add some lead flashing to the underside of these 2 bogies so they will not derail.....or I have also thought about adding a very slight spring between the top of the bogie and the remainder of the spigot....enough spring tension to keep the bogie on the track, whilst not being anywhere near enough tension to reduce the amount of weight that the boiler exerts on the 2 power units.
I will be tackling this job tomorrow and will report on my results when I'm finished.
The front bogies will be treated the same as I did with 6037: totally remove the spring and add lead flashing fore and aft of the "V" shaped bolt hole. The flashing needs to be shaped such that it slopes up/over the axles and is then attached to the top surface of the plastic cross section of the bogie, using Aileen's Tacky Glue.. (I just love this stuff!!!!!)
In the meantime, the PIG (3642 as shown above) arrived in the mail today. On first glance, it looks pretty damned good, but the tender bogies need some attention as the wheel-sets are dropping out of their holes (sideframes need tweaking). I have to totally dismantle the tender anyway, so I fit the WOW decoder and possibly the speaker. I say "possibly" because having watched several of Laurie McLean's Youtube videos, I am tempted to try and fit the speaker in the boiler, facing back towards the gearbox. However, I don't want to compromise the tractive effort of this model by having to remove any of the lead slug weight from the boiler. I may be able to move the slug further forward, but that could potentially cause issues with balance....too much weight being over the leading bogie, making the rear drivers inclined to lift up. Ideally, I would love to perfect a method of making the drawbar (between tender and loco) rigid and thus providing a system of getting the weight of the tender to sit on the rear of the loco and aid adhesion. It would require that the front tender bogie be "doctored" so that it floats. Hmmm...still dreaming about this idea and it probably won't happen.