Tiger Ausf E “F01” Gruppe Fehrmann

[AlastairCooke]

Hi All,
Update 24 Oct 22... decided to try to post more often but on specific subjects. So here goes...

Drive Sprockets
First, the machining marks were polished away using a grinding stone...

...which resulted in a reasonable rough cast texture. (This will be enhanced with Mr Surfacer 500)

The orientation of the sprocket teeth ring was modified, early on in the production run, to ensure that the mounting holes did not line up with the webs. (This was presumably to move a possible stress raiser away from this structurally important location.) Whilst the latest (Late) Tiger 1 release from Armortek depicts this change correctly, my base kit (2015 Tiger 131 release) does not. Consequently, some filling and re-drilling was required. I started with two locating holes...

Then the original holes were filled with Milliput and thin CA...

...before using the teeth ring as a drilling guide for the remaining holes.

Next, a length of track helped to align the other ring before another two locating holes were drilled.

Once again the teeth ring was used as a guide for the other holes...

The teeth were then chamfered on the lathe

Next...etch priming and enhancing the texture. I am considering adding a casting number... not sure what though... ideas welcome.

Alastair

[AlastairCooke]

Hi All,
Quick Update 4 Nov 22
More work on the road wheels before final seal coat of matt varnish. Scratches and rust spots added with varying degrees of intensity. These are the largest..

Sprocket, teeth rings fitted, etch primed and ready for bolt detail...

As my kit is an amalgam of two (Late Tiger 1 from 2012 and Tiger 313 from 2015) I have two etch brass frets and so I decided to detail both sides of the sprockets...

20221103_110116-doc.jpg (54.77 KiB) Viewed 4731 times

The fixings (7BA with 8BA heads and nuts) were secured by applying a drop of thin CA to each nut and allowing the glue to flow into the thread. (By the way, I have two sets of Armortek rear deck grills if anyone is interested.)

That's all for now
Alastair

[AlastairCooke]

Hi All,
Update 16 Nov 22...
Road wheels fitted, ready to roll (literally: needed to tie it up so that it did not roll off the lift!) Will eventually store the tank with wheels off the ground but thought it wise to let the torsion bars take the load for a bit and start to bed in.

Note the different shade of the wheels compared with the chassis and the paint removed in readiness for the application of sealant on the final drive case.

That's all for now...
Alastair

[AlastairCooke]

Hi All,
Update 13 Dec 22.
Preparation of rest of running gear.
Started adding Mr Surfacer 500 to pre-etch primed boss of idler to simulate cast texture. Will probably need at least one coat applied with a stipple action. The final drive gear was masked in readiness for a coat of dry lubricant.

Final Drive
Fitted motors and final drive casings. Ran the motors with 6V to check clearance. No evidence of scuffing of the primer inside so no need to mill out any material. Then Dry Molybdenum Sulphide lubricant sprayed on...

Gear secured in place using red Loctite, lubricant buffed up and Teflon disc added...

Area prepared for gasket paste.

Finishing sprockets
Base colour applied used Dunkelgelb Ausgabe 44 (RC061) as the sprockets are the later pattern...

20221202_081014-doc.jpg (64.32 KiB) Viewed 4408 times

Pin wash applied...

20221209_081938-doc.jpg (60.15 KiB) Viewed 4408 times

Improving sprocket hubs
First inside was machined square and flat around holes for cone bolts

20221203_143434-doc.jpg (38.6 KiB) Viewed 4408 times

Then a tube was machined to size and epoxied in place...

Drilled and tapped for M3...

Parts dry fitted after hole for zerk fitting drilled...

First coat of etch primer applied and outer bolts permanently fixed in place.

Modifying the Idlers
Rims polished on the lathe...

A rear cover plate was designed and 3D printed in black nylon. Plate then used as a guide for drilling mounting holes...

Holes drilled and scale bolts dry fitted...

Cast texture enhanced with more Mr Surfacer 500 stippled on, then sprayed with red oxide primer...

Base coat applied (using RAL 8000 Gelbbraun, RC063, as the idler is assumed to be from the original delivery)...

20221212_083057-doc.jpg (62.66 KiB) Viewed 4408 times

Pin wash applied, will do some oil dot weathering later.

20221213_094710-doc.jpg (70.97 KiB) Viewed 4408 times

That's all for now...
Alastair

[Gary Rafferty]

Hi All,
Update 13 Dec 22.
Preparation of rest of running gear.
Started adding Mr Surfacer 500 to pre-etch primed boss of idler to simulate cast texture. Will probably need at least one coat applied with a stipple action. The final drive gear was masked in readiness for a coat of dry lubricant.
20221129_094023-doc.jpg
Final Drive
Fitted motors and final drive casings. Ran the motors with 6V to check clearance. No evidence of scuffing of the primer inside so no need to mill out any material. Then Dry Molybdenum Sulphide lubricant sprayed on...
20221130_084754-doc.jpg
Gear secured in place using red Loctite, lubricant buffed up and Teflon disc added...
20221130_120609-doc.jpg
20221130_133445-doc.jpg
Area prepared for gasket paste.

Finishing sprockets
Base colour applied used Dunkelgelb Ausgabe 44 (RC061) as the sprockets are the later pattern...
20221202_081014-doc.jpg
Pin wash applied...
20221209_081938-doc.jpg

Improving sprocket hubs
First inside was machined square and flat around holes for cone bolts
20221203_143434-doc.jpg
Then a tube was machined to size and epoxied in place...
20221206_103147-doc.jpg
Drilled and tapped for M3...
20221206_150349-doc.jpg
Parts dry fitted after hole for zerk fitting drilled...
20221207_134434-doc.jpg
First coat of etch primer applied and outer bolts permanently fixed in place.
20221209_112302-doc.jpg

Modifying the Idlers
Rims polished on the lathe...
20221023_111024-doc.jpg
A rear cover plate was designed and 3D printed in black nylon. Plate then used as a guide for drilling mounting holes...
20221118_113818-doc.jpg
Holes drilled and scale bolts dry fitted...
20221203_090331-doc.jpg
Cast texture enhanced with more Mr Surfacer 500 stippled on, then sprayed with red oxide primer...
20221209_081648-doc.jpg
Base coat applied (using RAL 8000 Gelbbraun, RC063, as the idler is assumed to be from the original delivery)...
20221212_083057-doc.jpg
Pin wash applied, will do some oil dot weathering later.
20221213_094710-doc.jpg

That's all for now...
Alastair

Alastair

This is one of the most incredible builds I've seen on the forum outstanding work, look forward to seeing the end result.

Cheers
Gary

[AlastairCooke]

Hi Gary,
I am pleased and honoured that you think so. All the revisions mean that it is a very slow build, even though I do a bit almost everyday. I hope to be getting close to starting the turret by December 2023!

Alastair

[AlastairCooke]

Hi All,
Update 18 Dec 22 (Probably last for 2022...)
Idler installation
Swing arm fitted with custom made retention cap...

Note how much of the bushing protrudes to ensure there is negligible end float.

Plenty of grease applied to help swing arm slide in past the o-ring. Needed some 'gentle' persuasion from a rubber mallet!

Reflector required installation before left hand idler arm could be fitted. First, a pad was glued in place. On the full-scale vehicle this was tapped but, here holes had been drilled through to accept an M2 nut on the inside.

Then the reflector was primed, painted and fitted with 3mm A/F M2 bolts...

20221218_113834-doc-upright.jpg (41.16 KiB) Viewed 4096 times

Just a little touch up or rusting to do. (Nuts will be locked in place with a little Milliput.) Will keep the reflector lens masked until the rear has been matt clear-coated.

Time to position the electrics so I can finalise the lower mounting plate.
Starting with the batteries...

and the relays...

That's all for now...
Alastair

[AlastairCooke]

Hi All,
Update 5 Jan 23... Happy New Year
Final drive housing fixed in place. I have used 4mm A/F M3 bolts for the locations that may be visible and standard M3 hex head elsewhere.

20221218_134846-doc-upright.jpg (49.77 KiB) Viewed 3842 times

Electricals....
The battery/smoker tray (or plate) has been completed and test fitted. I wanted to finish this item before the motors are installed.

24 volt battery (2 x 12v) tray finished and mounting pegs for smokers fitted.

Plate in place...

...and populated.

Finally bit the bullet, and installed EdgeTX on my FrOS Horus 10X (Which was a challenge without the BootLoader option). Then could not resist some initial model setup and customisation

Hopefully I will have some sprocket movement very soon... That's all for now.
Alastair

[AlastairCooke]

Hi All,
Update 11 Jan 23
Significant moment has arrived... (more on this later...)
First...

Idler installed and showing off revised rear hub.

Then...

Sprocket fitted using standard taper bushing

Track section used to ensure correct positioning of sprocket.

View from front showing position of sprocket teeth in track.

Next a full length of track was made up. Started with 96 links but reduced it to 94 on fitting.

Finally with crossed fingers...connected the left motor to a DC power supply. With the hull lifted, so that the track was off the table, I began with only 6 volts gradually increasing the voltage to 12V. The track ran without any issues... so time to fit and trial the other one and then Loctite all the axle bolts.

Phew... that's all for now.
Alastair

[AlastairCooke]

Hi All,
Time spent today 'mocking-up' the front... starting to look at little like F01..

Alastair

[AlastairCooke]

Hi All,
Update 28 Jan 23
Laying out the power electrics.
This is a 24V system that will feed the motors, smokers, receiver, and possibly the turret rotation circuit). I intend to supply power to the receiver from the service electrics (12V system) as well.

Deciding on position of supply busbars and fuse.

Likewise for the relay switches distribution block. Note that all circuits have at least one split point so that they can be taken out should I need access to the torsion bars.
Starting the wiring...

24V system, note supply bus bars on left side along with 60A fuse. I will need to finesse the battery connections to avoid fouling the turret ring ... that's for later.

Motor electronics: Sabertooth 2x32 with voltage clamp resistors.

...now with relay switches wired up. The relay for the service electrics will be dealt with later...

Power relays installed and checked. I now have a switch activated 12V 70A one to link the batteries in series (Split/Join) and a 24V 70A one to energise the power circuit (On/Off).
Next job... wire up the 24v supply to the motor controller and to a 5V BEC to power the receiver. Note that the exposed terminals, busbars and speed controller will be covered later.
That's all for now...
Alastair

[Adrian Harris]

Looks like a very neat and organised layout but, if I may, I have two concerns.

1) Powering the receiver from a different source than the motors means you could have a runaway tank if the secondary supply is interrupted or becomes depleted first.

2) Having the two busbars next to each other like that is just inviting Sod to drop a bolt or spanner onto them.

Adrian.

[AlastairCooke]

Hi Adrian,
Thanks for your observations.
I hope the following will allay your fears....
1. I am using an FrSky Archer R10 Pro receiver. This has two XT30 power ports and so one will be connected to the power electrics (24V down to 5V) and the other will be connected to the services electrics (12v down to 5V). As the receiver will always use the higher voltage I should be okay The worst that could happen is a functional receiver but no drive power. To reduce the risk of this I am also fitting a FrSky FAS100 ADV between the power circuit and the motor controller to monitor the 24V system voltage and the current draw from the motors.

2. All exposed busbars will be capped with bespoke insulated lids when the system is fully fleshed out. The standard ones designed for these types of busbar are too bulky. At the moment the relays are installed only for testing then quickly removed. As things progress the busbars will be covered to avoid contact with any stray metal and the batteries will be disconnected physically when not required.

Alastair

[AlastairCooke]

Hi All,
Got the motors running under RC control today. Sabertooth fully wired up...

Note absence of 5V red wires from receiver, not required as it is independently powered.

Now covered with an ABS plate for protection.

Power electrics current/voltage sensor installed: data available via telemetry on Horus X10S.

30A max blade fuse installed into feed for 12V service electric circuit. Will be secured to rear electric plate when it is removed to set up the smokers.

Shot a short video...will try to upload

Alastair

[AlastairCooke]

HI All,
Got there....

It won't win any prizes for movie magic but you get the idea.
Alastair