Payloadbay.com fin wrap tool

[paul.nortness]

Hey guys,

I have a question....I am cloning a Maxi Alpha and I printed a fin wrap tool off of payloadbay.com. I made the wrap for the BMS T-80 tube I am using, but when I print it out, it is about a quarter inch short when wrapped around the tube.

Is this OK or should I try something else to mark my fins? Is there some scaling option I need to use when printing these wraps?

[awseiger]

You should be able to disable scaling when you go to print the wraps.

If this won't seem to fit right, use the one where you stand the tube up and the fins stick out (I don't remember what it's called). I use these almost exclusively for tube marking. Wraps are just too finniky.

[jadebox]

You should be able to disable scaling when you go to print the wraps.

If this won't seem to fit right, use the one where you stand the tube up and the fins stick out (I don't remember what it's called). I use these almost exclusively for tube marking. Wraps are just too finniky.

That's the Fin Guide tool:

http://www.payloadbay.com/index.php?...tion=FINGUIDES

It prints a guide like the one you describe with the center and edges of the fins included. All you have to do is use an angle iron to extend the lines along the tube.

-- Roger

[jadebox]

Hey guys,

I have a question....I am cloning a Maxi Alpha and I printed a fin wrap tool off of payloadbay.com. I made the wrap for the BMS T-80 tube I am using, but when I print it out, it is about a quarter inch short when wrapped around the tube.

Is this OK or should I try something else to mark my fins? Is there some scaling option I need to use when printing these wraps?

Adobe Reader or your printer is scaling the printout incorrectly.

After selecting "File" then "Print" from Adobe Reader's menu, make sure "Print Scaling" is set to "None." This fixes the problem most of the time.

I've added a 1" line to some of the printouts which helps you calibrate the tool. It's at the bottom of fin wrap templates. You can measure it to see if your printout is correct. The distance between the vertical lines should be 1".

If the line still isn't 1" long, click the "Properties" button after "File"/"Print." The dialogs that appear vary with your printer. Look for a "Scaling" option and set it to "None" if it is set to something else. If it is none, try setting it to "Zoom" and enter a value like "101%" if the line was too short or "99%" if the line was too long.

-- Roger

[Tarasdad]

I printed one of the Fin Guide Tool files to make a jig for mounting my Big Daddy fins. I carefully cut out one quadrant and glued it to a carefully squared piece of foam core board. Once that has dried I will trim out the BT curve and make sure all edges are perfectly aligned. This jig will allow me to ensure that all fins are perfectly squared to the centerline of the body tube.

Gotta start practicing good HPR building skills early, right?

[Rocketbuilder]

I use the payload bay.com fin wrap tool for just about every single one of my builds. I've never had any problems with scaling, using Preview on a Mac.

[paul.nortness]

Adobe Reader or your printer is scaling the printout incorrectly.

After selecting "File" then "Print" from Adobe Reader's menu, make sure "Print Scaling" is set to "None." This fixes the problem most of the time.

I've added a 1" line to some of the printouts which helps you calibrate the tool. It's at the bottom of fin wrap templates. You can measure it to see if your printout is correct. The distance between the vertical lines should be 1".

If the line still isn't 1" long, click the "Properties" button after "File"/"Print." The dialogs that appear vary with your printer. Look for a "Scaling" option and set it to "None" if it is set to something else. If it is none, try setting it to "Zoom" and enter a value like "101%" if the line was too short or "99%" if the line was too long.

-- Roger

I'll give it a go. The line was just a hair under an inch....and I do mean a hair....but over the length of the entire wrap, I can see how that would add up. I will give it another print and see if I can get it.

Thanks for the tip

[AlfaBrewer]

I always make sure to click the "Print Actual Size" radio button under the Size Options on the Print window. This is using Adobe Reader X.

[luke strawwalker]

Make sure "fit to page" is UNCHECKED or turned off in your printer preferences...

Otherwise check "scaling" and such for issues...

It's not hard to wrap a sheet of paper around the rocket so it overlaps itself, mark where it overlaps (with an arrow pointing back to the start edge that is overlapped just to make sure you don't mismeasure) then measure the thing in millimeters and divide by the number of fins.... That'll get you there with pretty decent accuracy....

The other way is the old drafting trick of drawing a line at an angle across the paper so that an easily divisible number greater than the actual circumference measurement falls on the start line and ending line-- say the circumference is 10.75 inches and you want four fins... lay a ruler so the start mark is on the edge of the paper and the "12" inch mark is on the line where the paper overlaps itself (extend it across the paper width by connecting the points at which they overlap on both top and bottom edge of the paper. Mark for the fins at 3, 6, 9, and of course the fourth fin will be at 12/start when the paper is wrapped around the rocket again. Do this twice using the same numbers/angles and then use the ruler to connect the points on both lines and extend them out to the edge of the paper squarely.

Later and good luck! OL JR

[JPVegh]

This is something that I've always done in cad. Use pi, find the circumference, divide by the number fins, set grid size, draw lines, add a line for the launch lug if wanted, print, cut, and mark. It sounds like a hassle but it really only takes a minute or two and the accuracy can't be beat. It's also great for laying out fin alignment guides, the radial copy feature makes it as easy as cake.

Of course open rocket lays out a fin marking guide for you so now a days I take advantage of that feature more and more often. How great is open rocket?

[blackbrandt]

Wait, openrocket has a fin marking guide?

[Rocketbuilder]

Wait, openrocket has a fin marking guide?

Yep. Go to
File-- Print/Export PDF. It will also print fin and transition templates. Very handy.

[paul.nortness]

Of course open rocket lays out a fin marking guide for you so now a days I take advantage of that feature more and more often. How great is open rocket?

That's right...I remember seeing that. It's a fairly recent addition to the PDF export I believe

[JPVegh]

Yep OR lays out the guide with fins and launch lug based upon your design. Pretty

[blackbrandt]

Cool. What version is that?

[JPVegh]

Cool. What version is that?

12.03

[paul.nortness]

Yeah, just mocked up a quick BT-80 based 3 finned rocket in OR, exported the PDF and printed....perfect!

[Rocketbuilder]

12.03

I'm still using version 1.1.9, and it does it too.

[blackbrandt]

Oh, I just saved a PDF of my Upscale Optima, and all I saw was a fin template, no wrap around fin template. I am using 1.1.8 though.