Cromwell Mk 4 1:16 scratch build Ludwig kit

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43rdRecceReg
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Re: Cromwell Mk 4 1:16 scratch build Ludwig kit

Post by 43rdRecceReg »

HERMAN BIX wrote:Smoke direction :O :O
You think of everything !
:haha: :haha: Well, HB- if I thought of everything, I'd be the Anthropomorphic supernatural supervisor. (Aka 'God'). :D
Nah, I've been around long enough to know that fixing mistakes can take a lot of time, and time's something I have less, and less of, each year. :/
I was thinking how the AK47 has an angled/slanted muzzle brake/ compensator that directs gasses upwards (stops the gun rising, by pushing the barrel down), and whilst I don't expect the smoke to improve traction, by bearing down on the tracks, I figured it would be good to concentrate it in a rearward direction. :D
"Get your facts first, and then you can distort them as much as you please"- Mark Twain.
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43rdRecceReg
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Re: Cromwell Mk 4 1:16 scratch build Ludwig kit

Post by 43rdRecceReg »

I'm just at the stage of completing the lower hull connections, and routing the wiring in the most convenient way. Wire spaghetti is not a good idea.
The detachable switch plate I made for the Cromwell, in it's earlier TK 60 format, included an in situ battery charging terminal; a vol control rheostat (not quite a knob :D ); smoker on-off switch and the power switch. Now, I only need the power switch as the latest transmitter handles the rest. I ditched the charging terminal, as it's not compatible with the TK 6.1s revised wiring.
Here's the remodelled switch plate.
Apologies for the layer of 'plastic dandruff' everywhere. I will vacuum it up sometime.
Click on smaller images to ENLARGE them!
Cromwell- detachable power switch plate.
Cromwell- detachable power switch plate.
It's a good idea to have (easily) detachable internals, from the maintenance point of view. However, given vibration from hustle and bustle, it shouldn't be possible for them to become detached 'in action', so to speak. The dovetail joints here see to that.
I use 3M double-sided tape to fix things in place, mostly. It's a lot easier than using screws or nuts and bolts. The only problem with it, ironically, is that it's SO adhesive that it's extremely difficult to peel it away when the need arises. The bond is almost strong enough to break the plastic the tape's attached to. 8O
3M double-sided tape of various types
3M double-sided tape of various types
I'm still trying to remove the residual tape from the base of the TK 60 unit. :/ Can anybody suggest a solvent for it that won't destroy the plastic?
Ultra-sticky 3M double-sided tape
Ultra-sticky 3M double-sided tape
Last edited by 43rdRecceReg on Tue Nov 02, 2021 8:42 pm, edited 1 time in total.
"Get your facts first, and then you can distort them as much as you please"- Mark Twain.
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43rdRecceReg
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Re: Cromwell Mk 4 1:16 scratch build Ludwig kit

Post by 43rdRecceReg »

Another issue is, I decided to include the IR receiver connector cable that comes with the TK 6.1s package, even though I'm never likely to do any battling (with anything other than a cold or backache :eh: :D )
However, the 3-pin receiver supplied with the TK unit has a JST that won't fit CH16 (terminal for IR Receiver). It needs a flat servo 3-pin connector. Have a look:
HL TK 6.1s ch 16- IR Receiver Channel
HL TK 6.1s ch 16- IR Receiver Channel
The other knotty issue, is that there's no visible indication of polarity and signal on the metal case of the MFU. Even after replacing the JST with a suitable 3-pin servo connector, it's hard to know if the pins are going to match up with those on the MFU's
It's also worth noting that polarity is not indicated for the 8 ED terminals. However, for your information, the '+' terminal is on the RIGHT when looking directly at the unit. You can see this in the pic below.
Here's the PCB revealed. Apologies that my iPhone has a problem with 'white balance' when capturing white objects.
HL TK 6.1s PCB
HL TK 6.1s PCB
Image
Image
Earth/ground is in the middle. I assume' 'out' will be signal, and the r/h pin the 3VDC '+' Again, the pinout on the receiver connector will have to match this. if my assumptions about terminal designations are wrong, do please say so. :thumbup:
Incidentally, if I even had an IR mushroom, it would now go into the engine deck, and not the turret hatch.
"Get your facts first, and then you can distort them as much as you please"- Mark Twain.
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Re: Cromwell Mk 4 1:16 scratch build Ludwig kit

Post by tankme »

I don't use the double sided tape as I don't like removing it and it tends to degrade over time. I tend to use the wide Velcro across the bottom of the tank and attach everything to it. Doesn't work for all items, but most. We have a product in the US called "Goo Gone" that should remove it. Should be safe for plastic. I've also used stuff like rubbing compound for removing swirls from car paint once the foamy part is scraped off.
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General Jumbo01
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Re: Cromwell Mk 4 1:16 scratch build Ludwig kit

Post by General Jumbo01 »

Come on you fairies! Tape removal is simply a matter of firmly rubbing your thumb over it with a rolling motion so that it rolls off the surface. True, after a few seconds your skin starts to roll off too but it doesn't damage the plastic. :crazy:
Owner - Fuckleburgh Tank Collection
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tankme
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Re: Cromwell Mk 4 1:16 scratch build Ludwig kit

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General Jumbo01 wrote:Come on you fairies! Tape removal is simply a matter of firmly rubbing your thumb over it with a rolling motion so that it rolls off the surface. True, after a few seconds your skin starts to roll off too but it doesn't damage the plastic. :crazy:
Yeah, I did that taking the badges off my truck and my thumbs were sore for a week... :)
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Dr Phibes
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Re: Cromwell Mk 4 1:16 scratch build Ludwig kit

Post by Dr Phibes »

43rd, nice to see you still working on the Cromwell build I started to follow some years ago now it seems! :D :thumbup: That British olive drab colour looks just about spot on too. As for removing that sticky stuff, I usually use WD40 though I would test with the plastic first - I personally have never had a problem using this but it's as well to be careful.

Regarding the HL TK6.0 polarity for ch.16, etc, perhaps this schematic can help, though I'm not sure the image size displays or expands properly (I'm not very well versed in uploading images here, I tend to click and hope for the best :crazy: )
Heng Long TK 6-1 schematic (2).jpg
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43rdRecceReg
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Re: Cromwell Mk 4 1:16 scratch build Ludwig kit

Post by 43rdRecceReg »

Dr Phibes wrote:43rd, nice to see you still working on the Cromwell build I started to follow some years ago now it seems! :D :thumbup: That British olive drab colour looks just about spot on too. As for removing that sticky stuff, I usually use WD40 though I would test with the plastic first - I personally have never had a problem using this but it's as well to be careful.

Regarding the HL TK6.0 polarity for ch.16, etc, perhaps this schematic can help, though I'm not sure the image size displays or expands properly (I'm not very well versed in uploading images here, I tend to click and hope for the best :crazy: )
Heng Long TK 6-1 schematic (2).jpg
Thanks, Doc!. Yes, I have that schematic, and all the others. The issue is one of terminology. IR hubs tend to have their own unique pathways, and terms. There's a useful site here:
https://learn.adafruit.com/ir-sensor/te ... -ir-sensor
Where it says 's' for signal on the diagram, there's no indication on the unit case. But 's' becomes 'Output' on the PCB itself, I discovered. I'm just highlighting a few niggles for future TK 6.1s users, with some answers for them. :D
But, it is irritating to have to graft a slimline three-pin (servo type) connector onto the one supplied with the MFU. That IR receiver JST would never fit.
I don't have a TK 6.0 to hand, but I imagine the receiver unit/cable bundled with the bag of cables, is the one for the TK 6.0. :problem: It's a one bag-of- wires/cables-fits- all package. But it doesn't.
It's no big deal, really. Just frustrating.

Yes, I began this build back in 2017. I had it the testing stage two years ago, but was thwarted by the mildly oblate shape of two gears in the R/H gearbox, and the track sticking. Thereafter, I was lured away by other projects... a familiar story to many, I'm sure. :D Yes the SCC15 Olive Drab (British armour 1944-45),is only made by MIG, I believe,and was a great find. It looks the part, and is a treat for the airbrush. It never gums it up.
I'm really glad you're active on the forum again, by the way. :thumbup:
I've had a few short restcures myself; but the lure of the build is a hard one to suppress. :thumbup:
"Get your facts first, and then you can distort them as much as you please"- Mark Twain.
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43rdRecceReg
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Re: Cromwell Mk 4 1:16 scratch build Ludwig kit

Post by 43rdRecceReg »

Having refreshed my memory on the layout of the TK 6.0, I can confirm that the IR module connector (for the mushroom), supplied with the set of wires for the TK6.1s, will fit the Tk.6.0 but NOT the tk6.1/tk6.1s
So, if you're inclined to buy the 6.1s package (and why not? It's the best HL unit, so far :thumbup: ), be prepared to dump the over-chunky 3-pin JST on the IR receiver cable, for a flat 3-pin servo type. You'll also have to shift the wires around so that the black goes in the middle, white to the left, and red to the right. :) This matches the pinout on the unit and PCB.

When fitting the flat two-pin IR emitter to ch 15 (next to the receiver 3-pin), note that the 6v + pin is on the right, so the red lead goes to the right and the white to the left, when looking directly at the unit.
Servo connector needed by IR receiver
Servo connector needed by IR receiver
This is the flat servo 3-pin connector, that needs to be grafted onto the receiver leads.
Receiver cables soldered
Receiver cables soldered
IR cable graft shielded
IR cable graft shielded
IR receiver connected to TK 6.1s ch16
IR receiver connected to TK 6.1s ch16
Here you see the Emitter (ch 15) and Receiver (ch 16) wired in correctly.
Image
Last edited by 43rdRecceReg on Thu Nov 04, 2021 7:10 pm, edited 1 time in total.
"Get your facts first, and then you can distort them as much as you please"- Mark Twain.
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Dr Phibes
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Re: Cromwell Mk 4 1:16 scratch build Ludwig kit

Post by Dr Phibes »

Ah, yes 43rd I can see what you were talking about now (excuse my confusion if appeared that way). I have the 'Haya 6.3' in my Chieftain (which is basically a re-badged HL TK6.1 though he seems reluctant to admit it) and indeed the pin-out does have these idiosyncrasies. Obviously, the three pin servo plugs typically have the live (red) in the middle, etc, but on the 6.3 it likewise on right of the Ch.16 pins.

It's worth noting too that the LED array pin-out places all live (red) pins on the right (outside of the board - this is not clear on the schematics I have at least). The exception, however, with Haya's board is that LED 1 alone places the live (red) pin on the left, or at least that is what they say when using this led output to control the smoking barrel board. This might be misleading, though, because to be honest I haven't actually checked polarity on this led output, I left that part of my Chieftain's harness as supplied.
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