Tweet
The stern of the Zulu prior when launching., The shape is very Close to the later Foxtrot.
-
The stern of the Zulu prior when launching., The shape is very Close to the later Foxtrot. -
And lent from a Type XXIComment
-
OK Men..... herewith the planned vent hole pattern for the Zulu. I asked a professional etcher to do this work for me but his head exploded when I sent him the drawings. Sigh. So, I'm going to do it myself, myself etc etc. You might remember that when I attempted to do this on the Romeo build it resulted in an unholy ****up, BUT, I have learned since then that the artwork is actually important. Black has to be blacketc etc. With that in mind I have taught myself to use Inkscape and produced the drawings for the brass etching. Here is the vent pattern. Please have a look and let me know what you think.
Comment
-
Nice and tight. You da man!OK Men..... herewith the planned vent hole pattern for the Zulu. I asked a professional etcher to do this work for me but his head exploded when I sent him the drawings. Sigh. So, I'm going to do it myself, myself etc etc. You might remember that when I attempted to do this on the Romeo build it resulted in an unholy ****up, BUT, I have learned since then that the artwork is actually important. Black has to be black
DavidWho is John Galt?Comment
-
Very nice! How did you do your fill up work for the result you show here?Comment
-
I started with a hand draw plan of the vent holes; then re-drew it using Inkskape in black and white, then (the interesting bit) I reversed the image and printed it out. What you see is a trial fit to make sure that the printed image is the correct size for the boat. Once I've done the deck and all the gratings, I'll print it off on the laser printer onto a piece of Press n' Peel blue etch mask, then run it through a laminator with some brass sheet to transfer the image onto the brass. Then paint the back side of the brass to protect it before dunking it in feric chloride for about 30 minutes. After all of that, I might have some usable vent holes!Comment
-
This is the deck plan. Almost ready to etch some brass.
Comment
-
i am very interested in how it turns out, I need to make some gratings for the Walrus I am building.If you can cut, drill, saw, hit things and swear a lot, you're well on the way to building a working model sub.Comment
-
Tom. These are the first of the below water side gratings for the Zulu. The process that I am using relies on blue Press - n - Peel circuit board transfer film. There is another process which uses light sensitive paint (which I am unable to obtain, unfortunately). You can see that the process that I am using is not perfect. The transfer film is tricky
to use and there is some break through of the feric chloride etchant that results in pits or irregular shapes. Inspite of that the overall result is pleasing.
The vents on the left and right have been lightly sanded to remove the oxidisation; the centre one has not yet been sanded. You can see lots of break through at this magnification. If you are interested I'll post some photographs of the whole process, step by step.Comment
-
Please do! Thank you!If you can cut, drill, saw, hit things and swear a lot, you're well on the way to building a working model sub.Comment
-
This is a test fit of the metal deck on the plug. Seesm to fit OK.
Comment
-
I mounted the plug on the jig today and began marking out the various lines. She has quite a lot of freeboard and, subsequently, lots of weight above the waterline. Might be a challenge making that work later on. After marking the line I began mountingbthe etched metal bits. Once I'm finished with that I'll place masking tape over them and then fair them into the hull.
Comment
-
Tom, this process starts with appropriate artwork. It took me ages to find a program that would produce black and white., Sounds simple but its not. Inkskape eventually saved me. Artwork should look like this:
Once you have the artwork finished you take a sheet of Press-n-Peel blue and print out your finished art using a laser printer, thus:
Next, you use a domestic iron (set in my case to "wool") and press the image onto a sheet of brass. I'm using .005 thick brass sheet because it is rigid enough to handle easily and gives enough relief in the finished article to actually make going through all this crap worthwhile! Once you iron the Press -n-Peel down it looks like this:
Comment
-
Once you have the artwork on the brass, you peel off the blue carrier film and you are left with (usually) a less than perfect imprint of the artwork. I've tried all kinds of things to make the blue stuff adhere better but nothing has produced a perfect result. My advice is to sand the brass with 1200 grit paper then clean it with acetone. That will produce a reasonable result but not perfect. Like this:
All those holes have to be filled. You can use a permanent marker but I have found that enamel paint is better. If you look closely at the blue bits of the artwork you can see lots of porosity. ALL of those little pores are going to be etched unless you fill them in now. So your brass sheet will begin to look like this:
Once the front of the brass sheet is finished you have to do something to ptotect the rear surface (otherwise the etchant will just destroy it and meet your artwork in the middle of what used to be your .005 brass sheet). I have found through trial and error that fluro orange enamel is best. It resists the etchant very well and also shows up in the hols on the front surface when the etchant has eaten all the way through the sheet. Thus:
Once the back is dry its time to dunk that sucker in ferric chloride. This stuff:
Comment
-
After six or seven hours in the soup all of the exposed areas on the upper surface will be etched away. You can vary the depth of the etch by taking the part out of the solution and masking bits off before returning it to etch everything else. Like this:Cancel
I pulled this out and masked off the deck drain holes then put id back in to fully eat out the two rectangular access holes in the deck.
Comment
Comment