R620 noob-build - issues

[Hokey-58]

After getting excellent help out of my shift-gear-confusion, I thought it would be neat to mention other issues that come up, all in the hope that someone can relate and possibly explain how to fix things.

The first question relates to the fifth wheel. Anticipating a trailer coming my way sometime in the future, I bought the motorized trailer legs. It comes with a fifth wheel with the hardware for triggering the things the trailer is supposed to do. After attaching it, the associated servo etc to the frame, my fifth wheel leans forward. I have not seen that on any real truck, nor on any of the yt-clips I have rummaged through. So, have I missed something in the instructions or is this one of those 'problems' that mysteriously disappear if you just ignore it long enough? I should add that I haven't connected anything to a battery yet.

/H

[Mad Ax]

Did you set the 5th wheel servo to neutral before you connected it to the 5th wheel?  Did the servo horn line up neatly on the splines or did you have to rotate it slightly?  It may be that you need to adjust the pushrod slightly to get the 5th wheel to sit flat.  You want it so that when a trailer is installed (and the 5th wheel is flat), the locking latch is fully closed so the trailer can't slip off, and the tongue that operates the remote legs is fully retracted.

You could adjust the rod a little more so that the at-rest position is angled slightly downwards (towards the back) which would be more normal for a full size truck with no trailer attached, as long as when the 5th wheel is pushed flat it doesn't cause the latch to unlock or the tongue to extent.

However I would avoid doing any of this until the MFU is fully connected and switched on, so you can determine where the true at-rest position of the servo is.

[CowTrucker]

Yeah, I think mine does that too.  But it isn’t a problem really and doesn’t affect operation.  The tricky part is setting the servo.  On my digital tx, I put it on a roller switch.  Roll back to open, roll halfway the other way to activate motorized legs up and roll full to lower.  (I may have that backwards not looking at my truck right now). But you know what I mean.  The tricky part is finding the sweet spot on the motorized legs where it goes one way and then the other.

[CowTrucker]

Mad Ax.  I might have to look at my 5th wheel and see if your suggested adjustment changes anything on my truck.  Good stuff!

[Hokey-58]

It appears to me that the pushrod has zero effect on the position of the fifth wheel. It only activates the thingy that moves back and forth to fiddle with the trailer. On the pic, the pushrod is not connected to the servo btw. And I am reasonably sure the servo is still in its neutral pos.

I think I'll let it be for now and see what may need to be done once I get everything hooked up.

Thanks for all the helpful comments, much more help than I would have expected!

/H

[CowTrucker]

Happy to help!  I’m not new to RC, but somewhat new to these Tamiya trucks, but I have assembled a trailer with OB1 wireless lighting, motorized legs, and I have made the 5th wheel operational.  My King Hauler came RTR and doesn’t have the MFC, but came with the Fly Sky tx/rx and does have full lights and sound.  But whatever light and sound system Toucanhobby installed is a mystery to me.  So I just installed the extra servo in an empty rx slot and calibrated.

I also learned many good tips from Youtube videos….so though I am not as experienced a builder as many others here, I feel I have a good handle on what’s what.

Having answered without looking at my truck upstairs, you reminded me that the servo does indeed just move the actuator for the legs and doesn’t change the angle of the 5th wheel.  But as I said, mine is the same as yours and it operates perfectly, so just move forward in your build, you’ll be OK.

If adding lighting be sure to get 3mm 5v lighting.  They do make them in color, but if the lenses are clear, I just colored them in with a Sharpie marker…worked great!  

Good luck on the build!

[Mad Ax]

If my memory is correct, there should be a pushrod that connects the servo to the 5th wheel latch, so you can drive away from the trailer after you have extended the legs.  The latch is on the 5th wheel, so the pushrod can have an effect on the angle of the 5th wheel - but I may be remembering it incorrectly, and my only truck with the Tamiya remote leg kit installed is buried away in its storage box so I can't check.

[Hokey-58]

After ignoring the fifth-wheel-issue for a few days it appears to have somewhat mysteriously sorted itself out. (Amazing how many problems just disappear if you ignore them for a while...).

I have managed to put things together a bit more, to my amazement, and satisfaction, there are no new real issues so far. I suspect the next 'problem' (=challenge) will be to fit the MFC-unit, speaker, receiver and the near half mile wires into the cab. If anyone has any good suggestion, I'd be all ears.

The pic shows how the bottom part looks right now. I am still waiting for the steering rod ends, otherwise it is done.

/H

 

[CowTrucker]

Looks good!  Good luck stuffing all the electronics in.  Check youtube for tips on how to stuff it all in.  I have yet to build my Aeromax with MFC.  Too much to do with other things before tackling that.

[Tamiya Fan 1]

Just read this. The fifth wheel should sit down in the back when at rest. There is a spring that should push it that way (on pin W/ sm. C-clip) when servo in nuetral.(or disconected)  But sounds like it is right know.

Also there are like 3 - 5th wheel plates with all the kits, and should be the squared off one, (that is how I see it) I bellieve comes with 5th wheel kit, (if that makes sense). They all work, but that "square" one works better I think because of a tang on the side of it does somthing. Alot of manual back ane forth! Also the flat plate (Connects to the frame) Should be the one that has the "notch out" for the servo rod (link), less hang up. That is what I always did.

Any way hope this helps.

[CowTrucker]

My 5th wheel tilts up in the back and downward toward the front.  I’m going to have to look to see if I missed a step or didn’t put the spring in right.  So far the trailer hooks up fine, but if you guys are saying it shouldn’t be that way, it’s worth a second look.  Is there any talk about any error in the instructions or a missing step?

[Tamiya Fan 1]

CowTrucker

There are 2 size link rods in the Support Leg Kits. Short one is for Globliner and longer one for most other trucks. Yours does look like the short one. If everything set right that is probably it. Measure it out per manual, shoudn't need to adust the length. See if that isn't the issue. I put this in another thread for you also.

Also I think the whole 5th wheel assembly can sit in two places on the frame (5th wheel being to far forward) ? I'm not a 100% on this, it's been a while. Something else to check.

Good luck!

[CowTrucker]

Thanks TF1!  I took it apart yesterday and couldn’t see what was making the 5th wheel angle forward down.  I’m stumped.  Everything is put together right and properly connected.  I used the correct servo rod as described in the manual.   (The long rod wouldn’t even fit, so impossible to have chosen the wrong one.). But that doesn’t mean I didn’t miss something, I just don’t see it.  I could always put some type of support bridge under the control rod which would lift the front of the 5th wheel.  

Hmmm…maybe I used too short of a servo horn??? That might be it.  I now have a new thing to look at….Thanks!

[Hokey-58]

So, after some (well, not "some"...) efforts and a bit of that luck cowtrucker sent me, I maanged to squeeze most of the cabling in to the cab. Then I started to check if things work as they should, following instructions from Hobbyconcepts-LLC, Teri Wilde and JF-RC on YouTube. I had to change the motor connectors to get it moving in the right direction (reversing the channel seemed to screw up other things).

The issue right now is that I cannot get the lights to work. Moving the right stick down is supposed to sequence the lights but for me, nothing at all happens. Has anyone any good idea about what I am doing wrong?

I have the shift/gear-control on the 3-way-switch (ch5), the motorized trailer-legs are now controlled by the potentiometer VRB1 (ch6) and have separate control of side-lights on switches SW2 (ch7) and SW4 (ch9). I'm not sure if any of that could cause any issues but cannot see how it would.

So, help me pleeease...

/H

[CowTrucker]

Hi Hokey, Thanks for the partial credit…lol.

 

Looks good!!!!!

 

Assuming you have all your lighting connected correctly, have a MFC 01 and a 4 channel transmitter with trim levers…..are you moving your right stick vertical trim lever all the way down to activate your light sequence while pulling the right stick down?

[Tamiya Fan 1]

You have to move the trim on that side down first and then the stick will do it's thing. You don't have to do them at the same time just trim first and then stick.

The wiring does add up! Truck is nice!

[Hokey-58]

Hmm, I should have mentioned that I am using an MFC 03, and I have an FlySky FS-i6x, set up for 10 channels, which the receiver supports obviously. And of course with a stick centering thingy installed. So, the transmitter doesn't have slide trims. I'll try the 'blip'-trims and see if that changes anything but...

 

/H

[CowTrucker]

MFC 03 should have the same tricks.  You should have success with your digital tx.  If I remember this right you have to:

1: Set your travel rates for your sticks at 75%.   Then calibrate your sticks with your MFC so 75% travel reads as 100% travel as far as the MFC is concerned.

2: then set a switch for dual rates and set each stick to 100%.  So when you flick your dual rate switch each stick then reads as 125% to the MFC which then mimics moving the trim slider.

I might have muddied the specifics, so refer to the youtube videos that are much more specific.  But setting a dual rate switch is what imitates the trim slider.

Good luck!

[Tamiya Fan 1]

Hokey-58

Transmitter still has a digital trim. move it downward a little and progress trim down, then lights should work off stick with a 4 pull change and then starts over. Trim should beep till it gets to end. I do not have Flysky radio though? But I know it works!

Bob from Hobbyconcepts on Youtube has video's showing how. (Using Flysky) Also has a store to get truck supplies.

You can check to see if your light work using manual control on the three position switch to the down position I think , and pushing the light button. Only lights will work. Also 3 position switch should be in the center for ful MFC operation. If not in the center position that could also be the problem. But you for sure need to move the trim down (even digital) To turn on light function. Other wise it is the horn.        Manual control is where you turn the truck On. #pos. switch is right next to it and can be moved by mistake turning truck on.I've done a few times. The positions are run truck only ( no sound or lights), fullly functional. and lights only.          Hope this helps!

Good Luck!

[Tamiya Fan 1]

I just looked at pic. of your truck and that switch looks in the UP position to me. Put it in the middle. That would be RUN ONLY, NO EXTRAS.

[CowTrucker]

TF1, You have a sharp eye!  

That’s interesting that you can do functions with digital trim…of course… it makes sense.  But setting dual rates lets you do all the extra functions with one flick of a switch.  I guess one is not better than the other, just personal preference.

Either way, I always end up getting my Brother P-Touch label maker and print out function reminders and paste them all over my tx.  There’s no way I’d remember what all those switches and sliders do.  I have too many planes and trucks and tanks and cars to remember what each does….lol

[Tamiya Fan 1]

That's funny I mark everything also.Transmitter and wiring with a label maker.

Switches are probably easier but once you get used to the regular way it isn't to bad. What you prefer. When I started I used the futaba FH-1straight up 4 channel that was recomended.( before 2.4gz) Later on switched to 1 radio for all trucks, a Futaba 8 channel and still did it with the trims.

Yes, you work the transmitter just like in the manual. The trim instead of sliding switch, it is done with didital button switch which has to to be held till it gets to it's end point. Then of course when done push it again to center. ( horn will then work)

Also with the MFC-03 you can work it where you hear the driver get out and walk by working with the sticks before you start it. Bob/ Hobbconcepts does a video on it and is in the manual also. MFC-01 does not do it though.

[Hokey-58]

Good morning (here it is anyway...), and thank you all for your help! The switch was actually in the middle position so that was not the issue. And the D/R was set at 75%, as per instructions from Bob/Hobbyconcepts' great yt-video. So, I was kind of depressed but decided to try to reset everything and start over from scratrch. But with one modification, I changed the D/R to 65%. And lo and behold, everything worked just fine!

So, much thanks to you guys, I am now a very happy beginner in this. The only thing that remains to do is fitting the steering rod as I am currently still waiting for the offset rod-ends to arrive.

Once all is up and running, I'll add some more pics of the truck. Then it's time to get a trailer for it as well...

/H

[CowTrucker]

Glad you sorted it out Hokey!  That was some serious logical thinking!

I’ll remember that if I ever try to set up an MFC with a digital tx.  If 75% doesn’t work, try 65%….lol

Good luck and have fun with trailer selection!

My experiences…..Most versatile trailer at the best price is the Hercules Hobby 3 axle reefer trailer.  Www.rcmart.com has the best price.  If you hate the European 3 axle look, you can adapt it with 120mm dual axles and dual wheels, and just put two sets of dual wheels, which is what I am doing.  RCmart is also the only place I know of that sells the OB1 remote bluetooth lighting system, which (now) works perfectly.  Though my set had some issues, and after some failed attempts at reprogramming, I did a full reset to default and all of a sudden, everything worked perfectly! Trailer has brake lights, reverse, turn signals, and room and power for as many side lights as you want.  I put 3mm 5v lights in the screw holes which are perfectly spaced.  I started with the Hercules Hobby flatbed trailer which I load with a Carson forklift.  Three more trailers to build!  

I got shipping confirmation from www.tamiyadecals.com, which sell full decal sets for the reefer trailers.  The selection is extensive!

Here’s a great video of a trailer conversion to 2 axles and taking details to the next level.  I really like the 2 axle look on it….but then again, I’m in the USA.  You might be more accustomed to seeing the 3 axle versions.  Personal preferences….lol.