kms bismark

This topic is empty.

Viewing 8 posts - 1 through 8 (of 8 total)

Author

Posts
3 November 2020 at 02:59 #92133
chris fenerty
Participant
@chrisfenerty25956
hello everyone,

does time change with scale,

my ship that i am constructing is 2.6m long. the turret is suppose to do a 22 second full rotation in real life, so because my ship is a lot smaller will the scale time change. i intend to use a hollow shaft stepper motor with a 1.8 deg step controlled by a micro stepper so i can get smoother travel, the hollow shaft allows me to raise and lower the guns through the use of another actuator.

the radar rotation speed is also in question.

any feedback will be very much appreciated
Advert

3 November 2020 at 02:59 #7194
chris fenerty
Participant
@chrisfenerty25956
turret turning speed
3 November 2020 at 09:17 #92135
ashley needham
Participant
@ashleyneedham69188
Vexed question indeed. I am bound to say that things like turning radars have to look..right…and not necessarily be the correct scale speed.

BUT

Can you scale movement? A radar turning at 60 rpm in real life would turn at 60rpm in any scale?

My feeling is that nice smooth rotation is the key rather than worrying about how fast….as above, I would aim for the same rotational speed as the real thing.

Another viewpoint…if you made a video of the boat from really close up, so it looked full-size, how fast would you expect to see the turrets rotate??

Ashley
3 November 2020 at 18:48 #92144
chris fenerty
Participant
@chrisfenerty25956
hello ashley, i intend to use a stepper motor with a built in gearbox controlled with a micro stepper control for smooth movement of her radars, but you can buy motor gearbox units which need less controls for actuation, but i do not know the speed of her radar

a lot of historical information is hard to find
3 November 2020 at 19:22 #92145
ashley needham
Participant
@ashleyneedham69188
I can’t imagine the radar turned very fast due to the relatively crude electronics, however, if you were able to find out how fast other contemporary radars turned that might be a start.

Perhaps bear in mind that if it went very slowly, you would not notice it on the model. Another thing is, who else would know how fast the radar turned? Whatever you choose would be correct….

Ashley
3 November 2020 at 19:38 #92147
Colin Bishop
Moderator
@colinbishop34627
As far as I am aware the radar aerial on Bismarck was fitted to the front of the main armament director and would have rotated with it as it trained on the target and not turned independently.

As far as the main armament and director are concerned I would have thought that 6-10 seconds for 180 degrees on a model would look fairly realistic. The turrets would normally follow the director of course.

Colin
3 November 2020 at 20:33 #92149
chris fenerty
Participant
@chrisfenerty25956
hello collin,

i have found out that the main turrets can move approximately 270 degrees full rotation @ 22 seconds so if i move them a fraction slower no one would ever know, i will peruse my plans again about the radar and firing director.

the plans i am using are the actual schematics showing every compartment and it`s use, i had the plans blown up so i could get some detail and realism which a small boat cannot do.

if you would like a set of the pdf plans that i have, i could upload them to which ever site you specify so the group has access so they can build their own

the tirpitz was the bismark`s sister and my plans say tirpitz and have a scale in the legend
3 November 2020 at 21:26 #92152
Colin Bishop
Moderator
@colinbishop34627
I think that in this situation the turning speed would be best judged by eye. Just a happy medium between whipping around and crawling painfully!

Colin
Author

Posts