Sd.Kfz 165 Hummel scratch + HL electronics

[MonsieurTox]

Shaping up well, this tech'y approach is very interesting.

Thanks, it helps a lot and save a lot of head scratching trying to solve paralax issue you get in photos when trying to get accurate measurements.

It has been a great help figuring the placement of the return rollers. They are in a straight line (with a -1.5 degree angle), the first three are evenly spaced (63.31mm at 1/16 scale), the third and fourth are 70.44mm apart.

I used measurement of the Trumpeter return roller to make mine in 3D, they are a perfect match size wise, the suspension housing is perfect too size wise (not 100% accurate regarding shape), however the wheel are slighlty bigger (about 0.5 more in diameter at 1/16), but maybe the tires of the Saumur Hummel are very used.

[MonsieurTox]

Well I received one of my HL Panzer IV chassis today (orderer 10 days ago from China... still waiting for the other one I ordered more than one month ago...).
So... I was right, the trumpeter wheels turn out to be too big. HL road wheels are about the diameter they shoul dbe at 1/16 scale. Unfortunatly they look pretty cheap and the trumpeter are great looking. Going to see if the trumpeter wheels are not too close if mounted on HL suspension arms.

I have started the Hummel chassis today.

I have printed templates on paper that I used to hand cut the parts by hand. I made one side wall by hand and copying it with my mill using the first one as a guide. All the other parts have been cut by hand.

You can see that I partially built the s.F.H 18 15cm Field Howitzer

Here's how it stands, I used 1.5mm styrene for the side walls (which is about the right thickness at 1/16), all the other parts are 2mm and every part you see it will be backsided with another 2mm part. 2 bonded layer of styrene are much more rigid than one sheet of styrene (for example 2 bonded 2mm thick styrene plates are more rigid that one single 4mm thick styrene plate).

[lmcq11]

Excellent. I can see you've done this before. I am no longer worried for the new guy. I like where this is going.

[Raminator]

Fantastic work Mssr. Tox, the hull looks perfect. A unique marriage of old and new techniques!

[MonsieurTox]

Thank you guys !

I did very few progress but that's progress nonetheless

I received one of my HL Panser IV chassis so I was able to continue the work. I roughly chopped the suspension mount from the HL chassis then I milled it flat and true with my mill.
Just noticed I did no that pics of the finished parts nor after assembling. Oh well, I'll take one later.

I also did some mold of some parts of the Trumpeter Panzer IV and of the HL Panzer III sprocket gear hub. I made resin castings but I noticed later than the dampers where not the same type than the ones used on the Hummel. Oh well I'll scratch a master, mold and cast copies.

I've continued to build the hull. I want to get as much access to the inner that I can. Trying to follow what they did on the original Hummel. HL Panzer sprocket wheels are used.

I then built the air intake conduits. I think I could drop the Panzer IV trumpeter fans behind them They would not be seen with the louvers of the intake anyway.

I worked on the idler wheels and track tensionners. Idler wheels are from the Trumpeter kit. They're beefier than the plastic HL ones and since I'm not planning metal tracks, metal idler is not an option at the moment. I reused the bushing (I think they just used copper though, bronze is too expensive for those cheap tanks ) from the HL idler.
I machined the track adjuster and the inner supports for them from aluminium.

I received today my Taigen metal wheels. Lots of fine tuning to get ride of too much wobbles of the wheels on the HL metal suspensions. It worked.
Tomorrow I will work on the return rollers. Here's again I'm going to use the Trumpeter ones (depicting the steel ones used on the Hummel, too bad I wont be able to use the nice Taigen ones with rubber ).
I just dropped the canon for the pics and the side panels. The canon is not in the correct position in the pics this is just to get an idea.

Thanks for watching.

[c.rainford73]

Brilliant work

[Marc780]

THAT is some mighty impressive engineering you are doing! If I had tried to do such a project, which I couldn't, I'd assume I'd use a Panzer IV chassis... this type of scratch building is far beyond me.

[MonsieurTox]

Thank you guys !

THAT is some mighty impressive engineering you are doing! If I had tried to do such a project, which I couldn't, I'd assume I'd use a Panzer IV chassis... this type of scratch building is far beyond me.

Thanks Marc, I can assure you that is not that difficult. The Hummel chassis is mostly a box so it's pretty easy to do !

Cutting the driver and radio operator compartment :

I've added some details on the HL Panzer III sprocket gear hubs :

In place :

Finishing the gun mount location with a strip of 3/10 mm styrene to get a neat edge.

I built the louvers of the side air intakes. I used 0.75mm styrene to get the correct thickness at that scale, unfortunatly I did not find my white styrene, only a piece of black one. Not a bid deal but I would have loved to see the model all white before priming it !

Tolerance here have to be as tight as possible, since it's cut by hand, you had to be very careful and patient. Tolerance accepted is less than 0,1mm.

Uncleaned parts :

It worked well :

hummel51.jpg (83.65 KiB) Viewed 812 times

[MonsieurTox]

In place (not glued) :

Some overall views :

I had to do the combat compartiment in 3 pieces so I can remove it.
The smallest one is to get access to the track tensioners like on the original one, the 2 biggest is to get access to the interior, electronic and such, it is for maintenance mainly. I will access the batteries from the glacis though.

I have ordered a 6.1S receiver/transmitter and sould get it soon. I'll be able to use servo to get gun recoil.

Thanks for watching. I hope you had a great Christmas, I wish you a Happy New Year !

[lmcq11]

Great progress.

I am curious to see how you will manage the gun shield. It was the most complex area to model on mine.