Tiger Ausf E “F01” Gruppe Fehrmann

[Christoffer Ahlfors]

Absolute perfection with everything!

I particularly like your incarnation of radiator fans. I did mine in a similar way, but much simpler and uglier and I used noisy, geared DC motors. Yours will be much better! Awesome!

[AlastairCooke]

Hi All,
Thanks for the complements and advice reference high build primer. I shall be buying an aerosol version for the large plates and a bush-on version to use for some of the cast texturing.

Alastair

[AlastairCooke]

Hi All,
Update.
Was hoping to show a completed stage by now but have been doing many different things leading up to laying out the position of the homebrew smokers. These may require some changes to the torsion bar mounting beams (additional tapped holes ...) so want it all sorted out before final disassembly.
First some pictures of the fan units with fans in place..

..and the revised engine deck grill

I have decided that some modifications can be made to Ivano’s, already excellent, HL230 engine model so here goes.
First the flywheels(?) at front and rear:

The magneto drive and fan drive housing gets some changes...

.as did the water pump..

Revised parts in place

I have plans to change the oil tank, carburettors, fuel pump/filters and possibly the inertia starter.
More detail added to the firewall front engine support. The riveted plate requires some more shaping...later.

Checking out the rear engine mount. This has a captive nut so that the model can be removed for maintenance when required.

More work on the upper fuel tank speaker mounts..

The mounting block (white plastic) will be attached permanently to the sponson floor allowing the speaker units to be removed when required.
Hope you found this interesting....
Alastair

[AlastairCooke]

HI All,
A quick update... you wait two months for one and then get two in a week! . I decided to check the fit of the engine in the chassis, as I have been concerned that there would not be sufficient clearance at the top for the engine cover . Everything checked out so it was good opportunity to see how things will look when completed. Here are some pictures

Thanks for your interest

Alastair

[simon_manning]

But the months are worth the wait, stunning build and detail level, shows what can be done with the Tiger kit, regards simon manning.

[AlastairCooke]

Hi all,
First, thanks to Simon for the kind words. This will be probably be my one and only Armortek build so it is all out to make it as special as possible.

Engine Exhaust & Smoker System and Electrical Power
After much thought I have finally settled on the smoker system to ‘animate’ the engine exhaust. The chosen design will only be used during start up and for a few minutes afterwards as well tuned petrol engines should not smoke when up to temperature. I would expect those tanks used by the training schools to be 'lovingly' cared for by the mechanics and technicians based there. I plan to have a cold start sequence that will have the sound associated with using the hand crank and then produce a bit more smoke (steam?).

As result of these decisions, I need a bespoke system. Stephen White’s vape based system is still an option for the gun smoke but I am reverting to the more traditional ‘bath’ approach for the engine smoker, as it should be easier to fit in the chassis and re-fill. Thomas (Benedini) has been a great help in supplying only the hardware I need rather than complete kits. I am using a Hammond die cast flanged enclosure for two independent units that will be controlled by a single microcomputer. The standard 24V (smoke) supply from the red power module will provide the wattage with two buck converters delivering 12V for the fans and 5V for the Arduino/Teensy. The fans will be PWM versions (probably Sanyo Denki 9GAX0412P3S003) so that I can change the speed with code. Likewise, I shall use MOSFETs to enable software switching of the heater elements. Triggering of the functionality will come via the RC transmitter/receiver using OpenTX or ETHOS(?).
Connection of the smoker outlets to the exhaust stack will be via flexible tubing and 3D printed plastic couplings as I want a scale appearance and the ability to remove the engine without dismantling the pipe work. Many hours with Fusion360 has resulted in the following design:

The union/pipework is designed to ensure that the flow is always upward from the smoker to aid with condensation runback.

exhaust-right.jpg (17.83 KiB) Viewed 5357 times

Note the design will mean replacing the Armortek exhaust stacks...
Layout of smoker boxes.

I plan to hide the piping in the engine bay with a pair of lower fuel tanks.
Yes, I have fitted the turret, for the first time!
This is to check clearances/layout for the batteries I have ordered... which are:
Two off PowerBrick+ 12V-30Ah Lithium Iron-Phosphate (LiFePO4) by PowerTech Systems (in series to feed the Armortek power module) and
one off PowerBrick+ 12V-12Ah (for other systems: Beier sound and radiator fans etc...)
Specs attached...

Eventually another battery will be fitted in the turret so that it is electrically isolated from the chassis removing the need for slip rings etc..
Alastair

[Robert E Morey]

This is an incredible build. Amazing details. Real treat. Keep up the great work!
B

[AlastairCooke]

Hi All,
Updates on several fronts...Trying out ideas for animating the fan units:

Red Board (Arduino Uno) driving two fans via A4988s with a potentiometer to adjust the speed. Eventually this will be a signal from the Rx throttle channel. Batteries arrived so tried out some layout ideas...

Gun elevation and recoil servo bracket fitted to check clearance with power batteries (two 12v 30Ah LiFePo4). Front hatches dry fitted to check clearance for hinges and periscopes.

Current idea for positioning of electronics.

layout5.jpg (67.97 KiB) Viewed 5247 times

I will require a shelf across the fighting compartment, between the ‘power’ batteries and the firewall; see blue area. Some of the 3D print parts for the exhaust also arrived so tried them out..

Next job... make up some leads so that I can check the state of charge of the batteries and put them into a storage mode if not already.

Alastair

[AlastairCooke]

Hi All,
Update 30 Jul 21
‘Home Brew’ smoker units.
As mentioned previously these are based on the Thomas Benedini design. I am using his smoker elements and wicks but different fans, enclosures and control. Here are some pictures of the enclosures with hardware attached, just need to attach the re-fill hose connector and smoke outlet.

I have changed the planned electronic design. The Armortek power module will still deliver 24V to the smoker heater elements, but now the 12V accessory battery will be used for the fans and micro-controller (Adafruit ItsyBitsy 5V). The heaters will be paired (four in total) with one in each unit coming on with engine start and the other when a certain throttle setting is reached (to be decided). Fan speed will be proportional with throttle position via signals sent from PWM compatible pins on the Itsy. The elements will be triggered by DFRobot MOSFET power control modules (DFR0457). I plan to connect each positive power wire to a 2A fuse before the load (motor or element). In addition a timer will be initiated on engine start so that the smoker system switches off automatically to simulate the reduction in smoke/steam once the engine has warmed up. The timer duration may also be set by the start sound used so that it is longer for a cold start... as its all in the code: I may have to learn C++, CircuitPython and MicroPython .

Engine upgrades
I have decided to replace the (Ivano) kit supplied fuel pump/filter units as from my research it appears that all HL230s were fitted with the same double action pumps. Although I used a reprint of the technical description and operating instruction manual for the HL230 P 30 I have not found any evidence that the P45 version had different drillings in the engine block for four single action pumps, as was the case for the HL210 P45. Indeed there is information that states that the HL230 could be quickly changed from the P30 version to the P45 version by an exchange of parts/fittings. Pump bodies shown below.

Note they are primed in black as they will eventually be painted an aluminium colour: this as been done early as I have found that the ultra high definition plastic used by Shapeways reacts with prolonged contact with air. As it may be a very long time before the engine gets painted I thought it best to play safe .

Alastair

[AlastairCooke]

Hi All,
Two years in! Here is a summary...followers of the thread may wish to skip this post.

So where have I got to?
Still a few things to sort out before a full dismantle ready for priming. I need to sort out the toolbox frame, mark up holes for bolts to secure the front roof frame and possibly adjust the mounting for the rear reflector as the original holes are partially covered by the plates added to bring the lower side plates up to scale thickness.

What have I decided:
Steel top deck and turret roof secured by magnets
Beier sound system,
Homebrew smokers based on Benedini elements with MOSFET control via ItsyBitsy micro-computer,
Radiator fan animation using A4988 stepper motor controllers and Teensy3.2 micro computer.
24V power from two 12V 30Ah LiFePO4 in series. Power on/off and circuit split (for charging) using relays.
12V 12Ah LiFePO4 battery in chassis for sound, fan animation, smoker fans, bow MG animation and lights. This will be energised via a relay and have fusing for each service.
Electrically isolated turret with 12V electrics, via a relay and with fusing.
FrSky Horus X10 Express transmitter and Archer R10/R8 Pro receivers.

What am I working on (or playing with ):
Homebrew gear box for gun elevation based on robot parts with servo actuation so that rate and end stops can be programmed.
Replacing turret rotation motor with one that includes a rotary encoder so that slew angle can be commanded explicitly and avoid areas programmed as required.

What is still undecided:
What mechanical/electrical features from the 2021 Late Tiger 1 model to include: bow MG animation, revised final drive....?
Precise means of providing flash and smoke for main gun.
Animated commander figure.

So still much to do... and then there is the ‘accurizing’. For those following this thread you will have seen that for me the kit and aftermarket parts are excellent starting points most of which can be further enhanced.

Alastair

[Vince Cutajar]

That's an impressive list.

How about adding smoke coming out of the barrel with the recoil?

Vince

[Christoffer Ahlfors]

Alastair,
I love the way you take on new fields! Each one of those requires a lot of energy as investment, but once you feel you are able to get something accomplished, it gives a lot of return energy and suddenly you are on plus!
It's great to follow this very competent build log! Thank you so much for taking the time to post!

[AlastairCooke]

Hi All,
Update - 18 Sep 21
I passed a major milestone, for me, this week . I have dismantled the chassis (wanne) ready for final drilling and then priming. I intend to reassemble when coated in etch primer then do the weld details before respraying the whole in red primer.

Once the chassis was in pieces I drilled the hydraulic lift-table and cover board (2ft by 4ft by 18mm hardwood ply from B&Q cut down to 2ft by 3ft 6in) to accept M10 bolts. Whilst I was at it, I also drilled some 6in wide strips that will be bolted to the sides of the board to allow clearance for use of a scissor lift. See below for pictures of the woodwork..

Chassis parts awaiting final drilling (low sun today... at least it is shining! )

Alastair

[AlastairCooke]

Hi All,
Update 25 Sep 21... so soon... well retiring from work gives you more hobby time !
Lower side plate mods - Part 1
Although I am not going for full interior detail, I wanted to replicate some key elements. The nuts securing the bump stops are recessed and so I filled the redundant holes, resulting from replacing the stock stops with those produced by Steve Winstone, by drilling and tapping for M5 brass bolts that were CA glued and then milled flat.

Then I milled a counter bore (6.0 x 4.5) followed by another (8.0 x 1.5). Standard M3 nuts were pulled into the 6.0mm hole to provide a secure fixing for the stops.

The nut was covered with a standard M3 washer and then a thin washer made from 0.005 Plasticard. This design enables use of a smaller 4mm A/F nut (from Knupfer) for a more proto-typical look that does not compromise the security of the bump stop fixing.

It is now time to bond the belly plate laminates together to produce a single plate equal to the original thickness (3mm) but with the required external detail. I have held off from doing this until now, as I was unsure what method to use. In the end, I decided to go with industrial strength double-sided mounting, or bonding, tape (3M GPT-020F). As alignment is critical and the adhesive grabs immediately, I used redundant plastic credit cards to hold the plates apart until bolts could be positioned to line everything up. The slightly thicker stiffener plates also helped keep things apart until I was ready.

These plates were then fixed using structural adhesive: Truloc Superloc 500. This two-part adhesive is very easy to use; Part A (clear) is spread over one item and Part B (green) is spread over the other. The parts are pressed together and then the ‘magic’ happens. A bond is achieved after 3 to 6 hours with full strength after 24 hours.

Another use for an extensive Tiger library!?

Stiffener plates bonded in place, ready for degreasing and a etch primer coat....

I thought you might like to see my makeshift paint booth on it's first outing. As my garage is too crammed and dusty to spray large items, I need an alternative. The tent is easy to put up, and take down, so is used only when required. I have not installed an extraction fan as I am painting in short sessions of a couple of minutes.

I may need to think again (?) when spraying the whole chassis tub (wanne). Perhaps a different type of respirator is all I need. Inside the ‘booth’:

What it is designed for... spraying large items.

That's all for now,
Alastair

[simon_manning]

Remarkable workmanship Alastair, i saw this Diorama on my Travels, 1/48 scale, regards simon manning.