N1 1/96 [Currell]

[Deriachai]

Hey PK,
I noticed on your site, that you used a circle cutter on the larger base pieces. I was wondering how you centered it. I use mine for formers all the time, but have had very little luck trying to center the cutter on an actual printed part.

[B-Manic]

this method is very easy

Finding the center of a circle - the easy way

[Deriachai]

Finding the center surprisingly isn't actually the issue.

The NT circle cutter which both PK and I use, has a rubber pad on the bottom to not pierce the paper. The problem is trying to get that evenly over the center.

[Paper Kosmonaut]

Originally Posted by Deriachai

Finding the center surprisingly isn't actually the issue.

The NT circle cutter which both PK and I use, has a rubber pad on the bottom to not pierce the paper. The problem is trying to get that evenly over the center.

Deriachai, have you ever tried to unscrew the rubber pad? underneath is a very spiky pointy bit. I have ditched the pad long ago. (I put it in the container underneath the cutter. They actually shaped it to store it there.)

And indeed, finding the center of a circle is not that difficult. I also have a tips and tricks page on my blog where I explain how to do it.

Almost all of the circles of the Currell N-1 have a cross line in the middle to locate the center.
The biggest issue with the N-1 actually is its own center line. the latticeworks between the stages make the rocket a little tricky to align. Zoli (Merzo) who has built the N1 a long time ago built a rig to accommodate the rocket and keep it completely straight. I think I am not smart enough to build such a device.
Building goes slow, but there is some progress. Soon the second stage will be ready and shown here.

And Bengt, Ralph Currell offers an A3 and an A4 version on his site. This one is the A3 version, which is 1/96. I didn't have an A3 printer at the time I printed this one, so it was done in a copy shop. That makes this a laser printed model, at 200+gpm2 paper. Very very sturdy. Almost too sturdy in the details. I am aware of the troubles with laser printed models, the toner layer chipping off and stuff. Didn't happen up till now. It indeed looks very metallic and another advantage is that the white glue I use doesn't stick to the surface. It is easily removed when I mess up. To make it stick, I roughen up the surface with either sand paper or even removing the toner layer or just carefully using my Xacto knife, cross-carving the surface layer of the rocket where I need to glue something.

[mhvink]

In regards to the pad at the bottom of the cutter, I have a simple fix for this. I just use a plastic circle template and use the hole that is JUST a hair larger than the pad and draw a circle at the cross hairs on the paper. Then put the cutter pad in the center of the circle you just drew and your cutter is centered.

Mike

[Deriachai]

I had seen the spike, but was hoping to avoid it so as not to punch holes in the paper, but if that is what is needed, I will find a way.

[Paper Kosmonaut]

Originally Posted by mhvink

In regards to the pad at the bottom of the cutter, I have a simple fix for this. I just use a plastic circle template and use the hole that is JUST a hair larger than the pad and draw a circle at the cross hairs on the paper. Then put the cutter pad in the center of the circle you just drew and your cutter is centered.

Mike

Hi Mike, such a device is provided with the circle cutter I use. It just isn't always that helpful, to get it dead centre is quite hard as it comes to millimetres precision cutting. And for some measurements it just is too small or too big.

[sparky00]

Originally Posted by Paper Kosmonaut

Hi Mike, such a device is provided with the circle cutter I use. It just isn't always that helpful, to get it dead centre is quite hard as it comes to millimetres precision cutting. And for some measurements it just is too small or too big.

I always thought it was just me who had difficulty with it...

[Paper Kosmonaut]

About cutting circles: When it doesn't matter and I also can just cut out a circle out of any random card, that's what I do. I measure the width of the kit version of the circle and just cut it from another piece of card. Especially when I want it to be sturdier.
When I actually need the piece from the kit itself, there's another way to precisely get in the middle: Using a needle, carefully make some small holes at the edge of the circle, try to make them opposite each other.
Then, flip the print over, and using a pencil and a ruler, lightly trace lines from one end to the other on the back of the print.
You will get an X (or hopefully a +) - type lining. The middle is your circle's centre. Now you can use the circle cutter's centre finder and put it over the pencil-drawn cross. Or, when the middle isn't visible in the end product, just use the pointy bit of the cutter's axle and cut your circle (the outer pinpoint holes can be used as a guide to extend or retract your cutting arm to the right length)
(phew, trying to explain something like this in another language than your own is not easy.)

[Deriachai]

I see no issue with your English, here or your blog.

And I tried that little plastic thingy that came with it, but always ended up off center.