DKM Tirpitz by MikeConnectrix - Scale 1:200 - 3D printed model with armament layout as at March 1943

[MikeConnectrix]

Hi, I am not sure if this is a scratch build or a kit. Since I am the creator of the files used in building this model, I suppose it is scratch built, but as the files are available for purchase, it could be considered a kit.

 

Unless told otherwise, I will proceed on the basis of scratch built and will wait a a day or two before proceeding for input.

[ccoyle]

It's not a kit in the most fundamental sense of the word, so the scratch category is appropriate.

[MikeConnectrix]

No great objections. So it begins..

 

I have published the build files for this project here.

 

I have worked on and off 1/200 scale models of Bismarck and Tirpitz over the last 30 years. I have completed a 1/200 Hatchette Bismarck, a Scratchbuilt 1/200 RC Tirpitz in MDF and Cardboard (Yes...MDF), and am currently working on this 3D printed version.

 

I started this model based only on FDM printing, but after some time realised that I could not get the level of detail required with FDM alone so started shifting parts to SLA resin printing. This model is therefore, a hybrid SLA FDM 3D printed model.

 

Equipment used is, but not limited to,2 Prusa MK3S printers, both Bears modified and one with the extended Z Axis height, a Protech RPE1 Resin printer and an Creality Wash and Cure station for Resin printing. I also have an assortment of cutters, sanding medium, Air brushes and Dremel tools along with various other bits of hobby grade tools and equipment. Nothing too fancy (apart from possibly waaay too many 3D printers, you could probably get by with just 1 FDM printer)

 

I have access to Laser cutters, CNC routers and lathes and a full custom PCB Lab with photo etch facilities and an SMD pick and place robot, but these are a bit excessive and will not be used with this model. I think.. maybe the Photo Etch facility, but I will try not too.

 

[MikeConnectrix]

So, we will start with the stand. Fairly simple sort of affair, print out the bits and they just clip together.

 

Files included for Bismarck and Tirpitz, just not sure of the Bismarck Name plate. Fonts... Whatever.

 

Nameplates are printed with a filament change from black to 4.45 mm then a swap to gold silk filament for the remainder. I printed these in PLA with an initial layer of 0.25mm and following layers of 0.15mm, but this could be increased to 0.25mm for speed if required.

 

The stand ends are handed. One end is for the bow, the other is for the stern. The name plate and name plate support orientation can be switched to allow for display in either direction.

Edited February 10 by MikeConnectrix
Add Detail and Misspelt Title

[MikeConnectrix]

Next is the hull. The hull parts will keep your printer going for some time. I print them at 0.25mm layer height for all layers with a 0.4mm nozzle. You could go a bit coarser to reduce time, but I haven't got much else on  (Said no-one..ever)

The hull sections comprise 2 sections and an interface part in the current design. It occurs to me that the interface could simply be printed directly onto the bearing part to reduce effort, I will investigate this.

 

Dry fit the 2 hull parts together and insert the interface. It is handed to follow the contour of the part being joined, but typically the hollowed section faces away from the join surface:

 

 

Once happy with the fit, remove the interface and apply enough cyanoacetate cement and re-install the interface firmly to it to the part with the bulkhead. Don't get glue onto the hull part being joined as we want to remove it to reinforce the interface join. Hold parts together liberally with masking tape and pegs/clamps etc.

 

 

 

 

When set, separate the now hopefully 2 parts and reinforce the join with soldering iron welding to fuse seams along with holes drilled through the bulkhead to create "rivets" where appropriate to strengthen the join.

 

Once complete, the 2 parts can now be permanently joined with glue, more rivets through the hull side into the interface join and sealing compound on the interface seam with the bulkhead part to keep things nice and dry.

 

 

 

The channel at the bottom of the hull is for a 20mmX3mm steel flat bar that runs the length of the hull to give it a bit more longitudinal strength. This bar has a cut-out towards the stern to accommodate the center propeller shaft. It does not have to be tight-tight, if you have problems inserting the bar into the propeller section, trim the bar appropriately (and with safety gear of course) to get a comfortable fit (the steel flat bar into the hull, not the safety gear :-<). There are extra channels along the hull at deck level to add further re-enforcing as deemed fit.

 

 

[MikeConnectrix]

So, for the last week I have been trying different methods of joining the hull sections to make assembly as simple as possible. While the original method works fine, it is a bit fiddly getting all the parts to line up perfectly so I have been searching for a better method.

 

First I tried printing the Interface directly onto the bulkhead hull section.

 

 

This requires extra supports while printing the part and does not produce a really good seam between the two parts when connected:

 

Then I tried printing the joining holes on both the bulkhead and the interface to allow them to be lined up easily. I also beefed up the bulkhead to provide extra support:

 

 

This provides a much better join line between the two hull pieces.

 

 

This is also the easiest method of assembly by quite a ways. Your print the 2 hull parts and the interface, super glue and screw the interface to the bulk head using the holes and some kebab sticks to keep everything lined up, then the hull section snap locks onto the interface and is mostly self supporting.

 

Reinforce the join with epoxy resin on the interface and welded rivets between the hull and interface. This works with the original hull parts as well, but is easier on the revised hull parts as the holes on the interface and bulkhead parts are pre-printed.
 

[MikeConnectrix]

Hull welded rivets:

Cover the interface joiner with Epoxy Resin and assemble the 2 parts to be joined. Align the parts as best as possible and drill a 2-3mm hole through the outer hull and the joiner wall:

 

I use a 3D pen to then flood the hole with melted filament. Slight pressure can be applied where appropriate during application to get a better alignment of the 2 hull surfaces.
 

 

"Rivets" can then be trimmed with flush cutters and join is ready for final seal with epoxy before final sanding/sealing/painting.

 

These 2 pieces were the experimental parts with the joiner printed directly with the hull piece, the poor quality of the join is obvious but should fill reasonably well.