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[T888]

As I’ve parked my Type 26 build, I’ve always wanted to building the Visby corvette. After digging out the plans I had in store I found a pair of Graupner small jet drivers.


So last week I ordered some sheets of plastic card which I got Thursday. I’ve already cut out the bulk head patterns and started to transfer them to the card.

[philk]

Love this boat mNy years ago a former treasurer of the cygnets club built one looked great on the water

[Martin (Admin)]

 
           

[T888]

Over the week end I’ve cut out the bulk heads and started the hull construction.




I installed the jet drives and have found I need the modify the reversing buckets as they clashed.

[warspite]

are they handed ?, and if so, what would be the consequence of reversing the handing as it looks like the buckets are not symetrical, assuming the sorter side is not outside i.e. pic 951 is the port side

[T888]

Hi warspite,


The buckets are handed, but the props are not. The modified sides face inwards to the centre line, so the wash will I hope run under the hull and give reverse flow.
 


From what I’ve found on previous jet drive projects is the buckets are only used at slow speeds (can steer in rever using the buckets) or emergency stop.

[warspite]

I see now pic 951 is the bucket modified by cutting it. 

[T888]

Hull nearly completed, just need to fill and sand ready for priming also need to add spray rails.


Once I’m happy with the finish I’ll add the hull openings and the main intake vents. The opening as there flush on the actual ship I’ll do by using solar film. This is very very thin and once topcoat is applied they will just be visible.

[frogman3]

HI Dave what happened to the belfast you was building ?
chrisb

[T888]

Hi Chris,


I’ve put it on hold as I was finding the base draw info I was using was way off and after seeing actual photos of the T26 I was having to do to many major mods

[frogman3]

HI Dave yes i see your point no good buildin the part if on the real ship they go an alter it is it  so makes a lot of work for nothing but i'll be followin  as im goin for a sail sunday up at norwich pond with my norfolk first time this yr just got to hope she still works  okas she hasnt been powered up for a yr or so just hope for nice wheather
ATB SIR
chrisb

[T888]

Hi All,




Progress to date

[Shipmate60]

Getting on well with her Dave.


Bob

[T888]

Thanks Bob,


I’ve just dug out a 1/72 NH 90 helicopter kit which will go no the flight deck.




How’s life in Scotland ?

[littoralcombat]

Great progress, very nice work Sir!
By coincidence, the Company I've worked at for over 20yrs designed, built and still maintains some equipment on these that is associated with the Waterjets/Ride-Control System. Namely, the Interceptor Plates on the Transom.
Our Engineers were always impressed by them during Service Work.
Nige

[T888]

Thanks Nige,


Photo of the actual stern

[littoralcombat]

Good picture Dave.
The four Hydraulic Cylinders that raise and lower the two Interceptor Plates are clearly visible, not to be confused with Trim Tabs (which is often the case), that these Ships do not have.
Nige

[T888]

Update,


I took the model to the pond yesterday to test for leaks and ballast trim. Two things came to light was a small leak around the jet drives and needed a bit of ballast to be added.


Next is to things to do is seal the leaks and fix the ballast in place and start to top coat the model.


I’m also a bit concerned about the motors (555) not having the power to push it along at a good rate, may need to upgrade (speed600) them, but I don’t really wish to go down brushless route.




I’ll post some pic once I’ve completed the top coat.

[T888]

Hi,


Pic of the mode so far, still need to make the main gun plus a few other bits.

[Chris67]

Hello !
Nice work ! 
It’s in one of my projects.

[T888]

Thanks Chris67,


I’ve done a second test today and the motors I’ve installed are just not powerful enough, so I’ll be changing them.

[HMS Invisible]

Thanks Chris67,


I’ve done a second test today and the motors I’ve installed are just not powerful enough, so I’ll be changing them.

You'll eke out more rpm by removing the 555 torque rings. You'll double the power with 30% higher voltage.

[T888]

Thanks,


I’ll try removing the rings, I’m running 11.1 Lipo’s.


I did look up the Gruapner data on the mini jet drive, they recommend speed 600 rpm 18200 @ 8.4v

[HMS Invisible]

The 555 no-load rpm will still be too low for a jet drive at 3s. And I think those who suggested 555 motors missed that detail and were thinking 1/72 multi blade props.
555s would have been a good match to the first batch of props of Chris's Tiger at 4s, perhaps 18v Pb.

[Chris67]

You can find jet here : https://kehrer-modellbau.de/index.php?option=com_content&task=view&id=25&Itemid=25