Early Tiger 1 from sPzAbt 503

[cahlfors]

A few videos to celebrate the new forum:



The engine is not on fire:


Crossing the antitank ditch:


Closeup:


Cheers,
/Chris

[Björn Johansson]

Hi Christoffer

Love them all,seems to have been
a great autumns day

[cahlfors]

Things are going slowly on this end. The current project is the pistol port, which is quite difficult.

The attached drawing illustrates one of the problems:


I do not have access to equipment that could make a flat in the turret wall to accomodate a prototypical port. Instead, I have to use a much thinner piece for the port and shim it with plastic metal to fit the curvature of the turret. I know - it is against my principles to use non-metal, but what can I do? Hopefully, it will hardly be visible.

As you can see, the oval hole would have to be quite a bit shallower than the prototype with this solution, necessitating some form of cosmetic compression. For this purpose I am currently in the process of learning FreeCAD to make a drawing and render it to experiment with the necessary compromises. Quite some task. I have not done CAD since 1985 and that was in 2D.

Suggestions of better solutions anyone?

Another challenge is making the sloping sides of the oval hole. I do not have a clue of how to accomplish that, although I have heard of a tool called a "file". Being a totally manual tool, I am quite reluctant to try - nothing straight could ever come out of one!

Thanks,
/Chris

[Björn Johansson]

Quite some challenge you got there

But I´m sure you pull it through

[Peter]

Regarding the use of the file, I have heard of metal workers back in the days that managed to use it to a degree of mastership that they could file parts with good enough precision to fit inside hydraulic systems.
A good selection of files, and a lot of time can give results that are excellent. Often I find that one rush in to grind down the part fast and you end up shaving of too much :(

If I understand you correct, you want to grind off part of the curvature (the red line) so you get a flat surface?
You dont have access to a mill (fräs)? Seems like a pretty straight forward job to mill that down a few mm, since it is aluminium?

Excellent work, judginf from the pictures you have provided,

/ Peter

[Peter]

Looking the pistol port up on the internet I now understand your predicament.
Without computercontrolled milling machine I think your best bet is using a file to get the proper shape on that hole.

or, the more complicated way, not necessarily guaranteed to give a better result than the file:
Build a forge, melt some aluminium, construct a new hatch/port from styrofoam, pack it in sand and pour the aluminium on the styrofoam. Beware of steam explosions

[cahlfors]

If I understand you correct, you want to grind off part of the curvature (the red line) so you get a flat surface?
You dont have access to a mill (fräs)? Seems like a pretty straight forward job to mill that down a few mm, since it is aluminium?

Excellent work, judginf from the pictures you have provided,

Yes, it's quite straightforward. Only, it takes quite some mill to fit a 0,5m dia turret into it and mill a 65 mm circular flat... It would cost like a used car and would occupy the entire garage, but there are a couple other things to be done on the turret I could use it for.

The picture is a prototype drawing - nothing I have done. I am still in the process of learning the basics of the tool. Ultimately, I am hoping to use the picture as a background as an aid and put my drawing on top to get the proportions right.

I like your idea of sand casting. Is that how it's done? That would be very useful for a lot of parts, but the true beauty would be CNC milling. Ahh

Thanks for your input,
/Chris

[cahlfors]

To keep the spirit up, I took a few moments outdoors today in the beautiful weather.

Panzer Marsch!


It could use a bit more smoke, don't you think?

The smoke is a bit more visible in direct sunlight:


Testing the durability of the steps up to the wood decking. It is quite solid, but iIf you listen carefully, you can hear it squeak under the weight of the Tiger!


Going down again, makes it quite obvious how heavy this beast is - stay clear!


Building progress is for another day...

Thanks for admiring my driving skills!
/Chris

[TBowman]

Hi Chris

Your Tiger looks fantastic! Heavy metal in the snow.

best regards
Tim

[cahlfors]

Thanks, Tim!

Progress is considerably slower these days, now that all the easy parts are done, but work lights are still shining in the workshop. I have some detail parts from Mike Stannard in assembly, but my relization now is that I should do the big things before I add delicate detail. How on earth am I going to do those without supersize tools?

I got a plans pack for the Tiger from the Bovington museum. What a piece of crap! The drawings clearly show the turret as being symmetrical and the gun off center! However, it was not very expensive and there were some interesting sketches too. One of them shows that the armor thickness was the same for the turret and rear and sides of the hull. Interesting! I wonder if that information can be trusted?

Cheers,
/Chris

[cahlfors]

Finally some notable progress!

Not very much, but notable.
This time I have addressed the rear mud flaps.

Before:


The stock flaps are quite OK. They are made of steel, lacking in detail, but quite rugged. Their only point of weakness is the brass hinges. I know that because I made a structural analysis using finite element methods and... Alright, I ripped them both apart by bumping into solid objects.

With this experience in mind, I might not be on the right track here but I decided to add Mike Stannard's mud flaps.

First, the frame:


The kit flaps come with the most difficult assembly work already done. To do justice to Mike's extremely skilled assembly work and to clean up my own solder, I set out to brush them up. I might have had wire brushing in mind, but ended up using a buffing wheel and some grinding paste. I believe the process is called "polishing"... I might have overdone this - it shines like a brass lantern - but I like it. Brass truly is beautiful!


The flaps fold like the prototype and have rear detail as well:


Check out this detail! Again, I have only done the assembly work. Anything good looking is attributable to the quality of Mike's kit:


As mentioned before, some difficult assembly work is done. Like the soldering of these structural members. Check out the solder joints! Can't see them? Look closer!


I am as happy as a cow with these new additions but, at the same time, quite scared that I might put some serious dents in them or even tear them apart already before getting out of the garage!

Thanks for following,
/Chris

[Kent W]

Nice and shiny Chris!

I can now see why you wanted your Tiger in the bare metal look.
This jewellery will draw spectator’s eyes and attentions were ever it goes.
Not that many has dare keeping them in bare metal but the end result is quite stunning.

Kind regards
Kent

[cahlfors]

Thanks Kent!

Good to hear from you and I am very glad you like it!

Thanks,
/Chris

[cahlfors]

Geez - you are not going to believe this!
As you know, I have always had the concern that the smoke might be a little too thin. Consequently, I have added a few smoke elements now and then. The situation really has improved. Just recently, I thought I should rebuild the smoke unit to put an end to all the leaks and to add a couple more smoke elements to give that last bit of smoke volume it has always needed. The family's Tiger inspection friends arrive tomorrow, so putting it all together well in advance (that's tonight... ) seemed to be a good idea. The test run of the smoker the day before yesterday went okay as far as I could tell. Nothing spectacular, but also no mishaps.

Tonight, though, with the smoker in the Tiger, the decks and turret in place, felt more like a real "smoke test" Starting the old usual way with preheat of the smoker, some sputtering from the elements, POOF! Gosh, that sounded like some real smoke power. Better "start the engine" to get the fan running. Sure, plenty of smoke coming out, but with a peculiar smell. Bluegreen light in the engine compartment! REAL FIRE!!! Cut the power! Turn everything off! What's going on?!? Disassembling everything again and taking out the smoke unit again revealed some serious burning of the connecting hoses, but everything else looked okay. It really looked like the smoke oil was on fire. Could it be that so many smoke elements in such a confined space might be enough to make the smoke oil catch fire? Maybe the idea of preheating (turning the power on to the smoke elements before start to get a good puff) is not such a good idea with this configuration? I checked that the wires were properly connected and not touching anything, reassembled the Tiger and made another try - this time without preheating. Better luck - reasonable smoke coming, revving producing more smoke, more smoke coming, still more as the elements got hotter and ... FIRE AGAIN - REAL FIRE!!!

Unfortunately, or possibly quite the opposite, there is no video of either the Tiger on fire or the look on my face. However, it might be quite prototypical with the engine overheating and an occasional fire. And a pale commander...

This has really been a nerve breaker and tomorrow's running will have to be without smoke. Too bad, after all the effort spent on the smoke effect. Maybe the day after tomorrow can be spent on a thorough investigation of what might be wrong (if there's anything left of the smoker - I have not dared to look). :shifty:

Maybe, all I need is just a bigger unit with more volume inside! And maybe then I could possibly add a couple more smoke elements!

Thanks for smoking Tiger brand (cough, cough)!
/Chris

[cahlfors]

It's been quite a while!
The fire was caused by a cracked smoke element. One of the new elements was bad, with the coil glowing brightly. After removing it, I discovered that the glass tube was broken. Don't know which happened first, but a cracked tube leaking oil onto a brightly glowing coil caused the smoke oil to catch fire. Now there is hardly any smoke at all, with many elements seemingly broken. What a bummer! :x

Lots of setbacks. The next one has been the Unimat's motor giving up, effectively putting me in a situation without motor tools: No drill press, no saw, no router. Have tried a so called razor saw and file, but found them very tedious to use. Rebuilding the motor would be expensive. For only ten times that money I would get a more adequate cnc machine (yes, yes, yes!)

Meanwhile, I have invested in a new work shop lamp:

Kjell & Co for very little money (Velleman brand) - heartily recommended. Will get another for the garage work area and another for my shoulder for general use.

Work on the tiger has been very slow indeed, but I have finally made the headlight brackets:


With the headlight installed:


Yes, the bolts are not fully tightened. Does anyone know of a useful 3mm socket wrench? Mine is too balky.
These headlights are full of errors and are not dimensionally correct, but so good looking that a person who saw it at a show said it made him decide that he was going to buy one of these tanks!

This progress looks like a minor step for mankind, but it was quite difficult to get things straight. The headlights are situated right on top of one of the deck fasteners. I have come to the conclusion that it would have to be deleted, but the support bracket underneath will be kept for stability. We will see how it works out.

Thanks for following this almost methodical construction story,
/Chris