Excavator side project

[cnr6400]

The CAD of the Mann looks great! but where will you get the lime green coloured steel for the rear wheels?   

Excavator also looks great. Don't know what that brown stuff around the deck works is though ...... 

They have that?       


That brown is some old fashioned organic steel, grown... I mean mined, put in those green areas called 'forests'.   

[gary.a.ayres]

Amazing work as usual.

I can't even guess how you manage to be so prolific.

[crueby]

Amazing work as usual.

I can't even guess how you manage to be so prolific.

Thanks Gary!  The elves ... I mean I, have moved along pretty well on this one!   


Been glueing and painting up the cab area this week, mostly out of plywood. The electronics have paused a bit. The wiring is all in place, but I have been getting a lot of glitching in the speed controls. After a lot of experiments and consulting the local gurus, found that once more than 3 of the ESCs were connected to the receiver the problems would start. Since there are six independent motors, this is a big problem! Tried different radios, motors, caps on the motors, positions, lots of things. Finally found some references online to similar issues, and that the manufacturer, Mtroniks, had seen it too. They started making a clever gizmo, an opto-isolator, which plugs in inline with the leads to the radio. It converts the electrical signal from wires to optical and back, getting rid of whatever noise, ground looping, drops, whatever the issue is (don't have a oscilloscope any more so can't look myself). So, ordered a handful of them, should solve the whole thing. The US dealer, who happens to be a friend of mine, didn't have any in stock so am waiting on the shipment from England, hope its not stuck in customs too long. By the time they are here I should have the cab all done.

[crueby]

Been playing on the Mann truck design in Fusion, added stake sides to the cargo bed, and decided to see how it would look if rendered. The materials on all the parts are still the default steel, so it looks more like the Delorean version!   

[cnr6400]

Purty! I'm going to buy shares in AutoSol polish if you build it to match the rendering!

Re your optoisolator-taters  for the ex-cavator  - I recall in my time at the big X we had a few of these gizmos on signal lines. If I'm not mistaken they were made by Sharp and Panasonic. They were a small PCB maybe 5 x 16 mm with in and out connections and a black box which housed the source led's (infrared as I recall) and the receivers. We had fun with one of the test engineers one day by quietly shining a laser on the black housing. Enough IR got through to seriously confuse the workin's. Test engineer was tearing his hair out trying to find the ^%$@^() glitch until we spilled the beans. He was not amused.

 Anyway, point of the story - if your source for these is holding you up you might check Digikey our Mouser or Newark or Allied to see if there might be an available alternate.

[crueby]

Purty! I'm going to buy shares in AutoSol polish if you build it to match the rendering!

Re your optoisolator-taters  for the ex-cavator  - I recall in my time at the big X we had a few of these gizmos on signal lines. If I'm not mistaken they were made by Sharp and Panasonic. They were a small PCB maybe 5 x 16 mm with in and out connections and a black box which housed the source led's (infrared as I recall) and the receivers. We had fun with one of the test engineers one day by quietly shining a laser on the black housing. Enough IR got through to seriously confuse the workin's. Test engineer was tearing his hair out trying to find the ^%$@^() glitch until we spilled the beans. He was not amused.

 Anyway, point of the story - if your source for these is holding you up you might check Digikey our Mouser or Newark or Allied to see if there might be an available alternate.

The isolators these days seem to be done inside a single chip (like so much now). The ones on order are from the same maker as the ESC's, and are set up to match the voltages/etc, and already have all the connectors in place, so worth waiting for them.


On one of the printers we did at the big yellow box, it had an IR LED as the sensor for whether the top lid was open or not. The Chinese factory loved swapping out parts from their cousin's factory up the road without telling us they were changing specs, and there were thousands of the one model printer made with LED's that had the life span of a June bug - long enough to be at a customer. We had to put in a menu option so the user could say the lid was open and to bring out the print head to change tanks. Other workaround was to shine a flashlight down inside the opening to trick the sensor!

[cnr6400]

 

Oh yes, the cousin, brother, or brother-in-law's factory up the road in China - a familiar and frequent situation, usually to save a few pennies. Happened many times at the big X also. Most costly one I recall was some brightly coloured parts used in some machines. Someone noticed the colour on one shipment of parts was a little off. They were bundled off to the QC inspection lab , near the security station. As the box passed the security shack, the radiation detectors alarmed indicating a serious hazard level. Building was evac'd and it was discovered during investigation that the B-I-L had got a great deal on some lightly used scrap plastic from the nuclear industry and reground it , mixed it with regular resin, and shipped parts hotter than a two dollar pistol. Luckily that shipment was detected before the parts hurt anyone and before they were shipped to customers. Makes you wonder how rigorous port side incoming inspection was back then (late 90's early 2000's).  Cost an absolute fortune to get rid of them safely. The creative B-I-L up the road has been a problem for several industries.

[crueby]

Okay, sent the 'Delorean' version of the 3D model to the paint shop, and got some basic colors on it:

Shows up the shapes a bit better. Also, in today's mail got the mock-up of the engine for it back from being 3D printed (no, I don't have a printer yet). I like getting the engines done like this, the shapes can be tough to keep track of from the 2D printed plans, and the plastic version is handy for picking out stock. I have a length of 1144 Stressproof steel round bar that is big enough to get the main engine block out of. When I first opened the package I thought it had been scaled up by mistake, then realized I had the steam chest and lids in place for the print.

 Here are a couple of shots of it:



The curved plate it sits on will be bolted to the boiler, the ribs under that go inside the boiler - silver soldered in place, then drilled/tapped halfway through for the engine to bolt onto. Not having any castings to fondle, this is a good substitute!   
So, getting closer to actually starting this build. I want to have the excavator done and out of the shop first, so as soon as the radio parts arrive that should happen. They got sent to Heathrow to fly over here, now they will be gathering dust in the customs warehouse for a while most likely.

[Brian Rupnow]

Looks really good Chris !!

[zeeprogrammer]

Your Fusion360 skills are exceptional. I need to take another run at it.

[crueby]

Thanks guys!    Zee, this is after about 4 years using it on quite a few models and other parts. Thier own video tutorials are a big help.

[crueby]

Got word that the isolators for the radio are in, going to meet up with my supplier buddy (he is in the local rc boat club, been running boats with him and his brother since we were kids) at the pond this weekend and get them. So should be able to get the excavator buttoned up and digging this coming week!

[zeeprogrammer]

So should be able to get the excavator buttoned up and digging this coming week!

Probably inappropriate...but looking forward to seeing you dig your own hole. 

[crueby]

So should be able to get the excavator buttoned up and digging this coming week!

Probably inappropriate...but looking forward to seeing you dig your own hole. 

Ummmm.... Errrr.... 

[crueby]

Got the optical isolators, and got them installed. Had to reconnect the power wire from the ESCs, since that is how the outer side of the isolator is powered, the wire had been snipped on each speed control so only one would power the receiver. Hooked all six up, and NO glitching anymore!!


 


So, now can button up everything, do final wire bundles so the cab will go on and off easy. Should be digging in a couple of days, video to follow then!


 


And after that, almost ready to start the Mann steam wagon project....