USS Jack

[manowar]

Moulds Part 6

So, for the final aspect of the new Permit hull mould, one last task was remaining to make it a real mould, just like turning Pinocchio into a real boy. It is good to do a post cure on the surface coat to bake in the details and take the epoxy to its maximum strength and set the release wax into all the microscopic pours of the new green mould. Instead of making a makeshift oven and by oven, I only mean to have a constant temp of around 60 degrees Celsius (140 F). I did this the easy way and killed two birds with one stone and that was by doing the first fiberglass lay up inside it. Here’s how it went;
My mould was waxed and had a nice coat of PVA applied with my touch up gun. I tried experimenting here because I intend this first hull to go to my sister who is in turn painting the box art for my kit packaging. She doesn’t have spray equipment or any of that kind of stuff, so I began her hull by spraying my Ful-Fill easy sand primer into the mould first before lamination. All she will have to do to paint is give the hull a very light wet sanding with 1000 grit. This ended up being really cool because it really made all of the details stand out strikingly and gave me a good chance to inspect my final work.









One note here, I sprayed the primer the day before I planned on laminating which apparently wasn’t a good idea because it shrank and pull up from the mould along with the PVA. So I ended up doing it all in one shot the next day.
So here are the results. The upcoming pictures aren’t of the master but of the actual reproductions; don’t be fooled because they are in grey. The thin layer of primer adheres extremely well to the hull, better in fact than if you actually sprayed it on cured epoxy. It captures the texture and detail perfectly. I think it will serve its main mission extremely well by giving the modeler an easily sandable surface that he can get rid of the orange peel left from the PVA application. The only drawback I can see is some minor surface pin holing, which means I have to adjust my spray on technique. If I can fix that then perhaps I’ll make this a standard on my boats









Joel

[manowar]

I forgot to expalin how

I forgot to expalin how the surface coat on the mould actually "post cures"! Simply, I heated up my fast cure West system epoxy by stirring the mix cup dipped into hot water, painted it on top of my primer coat and let it sit in the hot sun. The epoxy coat had heated up quite a bit past it's normal cure temp and set quite quickly as well. Lots of heat for what I wanted to accomplish. The primer coat also acted as a secondary barrier between the epoxy on my mould surface coat and the epoxy used for the repro surface coat. A nice thing just in case there are some small tears in the PVA coat, something that happened on the last mould which caused me some grief in trying to pick cured epoxy off of a green mould.

Sorry about that,
Joel

[manowar]

New scope rack

Hello everyone,

It’s one heck of a long time since I’ve done an update on this project and I figured it was about time to get one done.

I haven’t been idle on this project what with being so close to finishing all the retooling. All moulds have pretty much been done withstanding the long Jack hull and a very special part that has grown very close to my heart...Not! It’s the redo of the scope rack and man what a challenge. The reason for the remake here is because I didn’t like how my initial 4 piece assembly worked as it was just too hard for the modeller to get the scopes aligned and straight within the sail, a task that might require the modeller to have 3 or four hands! The goal with the new one is to make it one piece for easy slide-in installation into the new one piece sails, a feat very much easier said than done.

To begin (again) I had to decide what method I wanted to accomplish this task. Cutting multiple sheets with the shape of the inside of the sail and the mast holes was out, just too hard to do so here was my solution. But before I begin I must relate to you all that this was finally done with a clear mind and desire to work on the Permit, both of which have been severely lacking over these summer months due to all the other fun distractions and obligations. When trying to do model stuff when you don’t feel like it presents sub-par results (doing things over 5 times) and that just ain’t fun.

First thing was to produce the base material that held all of the scopes perfectly straight and aligned properly in every axis in relation to the sail. First I poured a sail using semi transparent urethane plastic with no re-enforcement. I figured it would be a good idea to be able to see what I was doing. The clear sail was cut just slightly below the sail plane shaft holes so that when put on a flat surface the front and the back were perpendicular with the table. Great care was taken when looking at the front of the sail to make sure it was 90 degrees as well. Final trimming was carried out on my circular table sander. The mast holes were cut out as close to possible, plus the bridge fairing as well. The sail top was tacked to a thick styrene board using CA and baking soda to hold it in place at four points.





Care was taken to align my drill press table with the bit using a speed square and brass tube held in the chuck so that they were 90 degrees exactly. When you assume the table is square and it isn’t, guess what that means? The project will have to be redone as you can rightly guess what happened to me! The press was used to drill into the styrene board using the sail caps’ holes as guides. Lots of bit changing was done here, in fact I did so much that I was able to master changing bits with the machine turned on…Just kidding! Don’t try that at home! Ha.



With the holes transferred to the styrene board the sail cap was removed and I cut out the faired holes using a file. Long brass rods (ensured to be straight) and the faired antennae were put in place through both the sail cap and the styrene board. Theoretically straight and that is what the long rod’s jobs are; to make sure of this. The clear plastic really helped getting the rods into their respective holes too.



With things found to be straight (finally!) the long rods were replaced with shorter versions of their appropriate diameters. Note that everything is greased with Vaseline like the inside of the sail cap, brass rods, plastic antennae fairings etc…



The base was sealed with modeling clay and white plastic was then poured in through the clamshell opening in the sail cap, filling in almost completely. Another wonderful thing about the clear sail cap, I could see if the plastic filled in all the gaps that it should have. Then, into the pressure pot to try to get rid of bubbles.







To get the plastic work piece out of the sail cap I first removed the rods then I pried between the clear and the white using old Exacto blades leaving two in place. These two blades were used as guides that would tell me where to stop closing my vise. With the clear lips placed on the vice I tapped out the white piece using a hammer and a dowel that fit into the clamshell hole.





It doesn’t look impressive in the picture, but now I have the base material in which to make a nicely aligned scope rack!



More to come on this thing tomorrow, I’ve already typed enough for one day…
Joel

[manowar]

Scope rack 2

Carrying on with progress on the new scope rack,

Now that we have a base in which to work with knowing the slots will hold the masts and scope in a straight like manner, we can move forth with making it look the way it should. It has to have allowances for the new bearing bosses that go inside of the sail, it has to allow for movement of the plane shaft crank arm, and finally it has to allow for possible retraction of scopes into the sail itself. In that I mean I have to remove material to allow the fast mastheads to fit while the mast hole wouldn’t initially allow for that.

This is basically engineering and building on the fly. One thing gets done like boring out a wider hole for the BRD mast and then you see something else that needs to be done like cutting out allowances for the sail plane bearing housings. Then you see that a slot needs to be created for allowing the shaft’s crank arm to move. An Air escape hole here, some weight reduction there. Whittling and cutting off a little here, filing off a bit there. I actually do have a milling machine, but found that the plastic material was a little too pliable to held firmly enough in the milling vise without getting damaged.

Here are a few pictures to show the progression of this ugly raw piece of plastic to where it stands now waiting for surface finish application and then mold. Once the mould is done I then can make a replica and modify it by replacing the BRD mast hole with the observation periscope fairing hole that they added later. Just a matter of note here in case you wondering what happened to the BRD mast (doesn’t everybody? Ha!) It was moved to where the UHF/IHF antenna used to be into a “mini sail” fairing attached to the top of the sail on the port side, and the UHF/IHF antenna was moved so that it sat atop the snorkel mast at the front of the sail. So, with the sail being so small and the navy using hindsight to find that it simply lacked the sensors needed to do the job they ended up making some masts doing double duty, in the snorkel’s case it housed a whip antenna and the aforementioned UHF/IHF antenna. 3 in 1 combo.













The finished part and mould to come,
Joel

[manowar]

Scope racks conclusion

Continuing on for the scope racks;
Ok, with the 62 version of the scope rack finished, I made a mould of it and then a casting. From this casting I then made the 79 version. In this version the BRD antenna was moved from the second last centered stern slot to the position by the UHF antenna just rear of the cockpit. In its stead was put the new observation scope. The IHF antenna that the BRD replaced was then moved to the top of the snorkel...capiche?? I hope I explained that right!




Its a nice snug fit into a 79 sail top. It’s hard to see here but now a cockpit interior can be modeled if the user wishes to go that far (to clarify, I didn’t model the cockpit details, but the general shape of it is there).




Now that the racks are complete its time to get to the last stage of this big project; the Jack hull final detailing and mould...oh and the towed array fairing too!
Joel

[manowar]

Hull Part3

This is getting really exciting for me, as now I can see actually testing and running a contra prop driven USS Jack. This has been one long haul and I think the reward will be worth it

I left the hull alone for awhile because when I do that I usually find a few things I don’t like and then fix them up. You’ll be happy to know that I didn’t find anything this time. Time to make the mould, Yee-haw! Of course, this means the surface has to be prepared first, and in this case I am going to go with a more polished finish than I had on my most recent Permit mould. Although I like the semi-gloss finish of how that hull comes out, it isn’t as easy to remove from the mould and that also means that mould probably won’t last as long either. And I am attracted to shiny things, so the Jack hull will be shiny!
I didn’t count how many steps there were to doing this, but there were alot. Final blemishes were filled and the hull was primered. Wet sanding starting with 400 grit wet sandpaper was done over the entire surface. I add a little dish soap in my water mix so that the paper doesn’t clog up on me. I like the orange smelling dish soap. It makes the sanding experience smell so nice. You will know when that course grit of sandpaper has done its job when it feels like the paper isn’t biting into anything anymore. It’s important to keep the paper clean of clogs so give it a dunk once in awhile in your sanding water. Once the sanding is done. Replace the soapy water and totally clean the hull from any remaining sanding slurry. I did this by taking the foam filled fibreglass hull halves into my backyard and sprayed them down with the hose, which is cool. I wasn’t able to do this to the Permit’s MDF plug for fear of having water leak by the sealant coating and create a possible problem. The sanding process was don using 400, 600, 800, 1000, 1200, 1500, and finally 2000 grit papers. Once the sanding was completed, I used a buffing wheel connected to my drill, used a little green polish compound and polished her up. This where the beauty in the finish really begins to come out and is very noticeable, and all your hard work pays off. By the way guys, this isn’t my technique. I learned this from our local auto body/model guru Brian Starkes. With buffing done, I used a sealer glaze product made by Mothers. It gets rid of small scratches and swirls and is applied using microfiber cloth, the same way as car wax. Speaking of car wax, that’s what we used next. I used Meguire’s Tech Wax 2.0. This stuff is absolutely incredible as you don’t need much and leaves an insane lustre. I discovered it when I needed something to wax my truck with and tried her out. I can actually see my reflection in the side of the Jack now! The last step is to wax the hull with about 5 or 6 six coats of mould release wax.




It's amazing the effect different light has on this hull, the hull was just moved into the garage for this next pic

More to come...
Joel

[manowar]

Damage Repair

Here’s what do to when you get damage in your hull finish in which won’t be acceptable to transfer over to the mould finish.
History: The hold down stud was threaded too far into the nut epoxied into the underside of the mould. This caused the finished to crack upward causing an unsightly blemish.

Verdict]http://i171.photobucket.com/albums/u319/Rapperkiller/P1011919.jpg[/img]
• Drill out damage with Forstener bit. Scrape off any other damage found


• Fill area with easy sand filler and then block sand down to flush with the rest of the hull
• Prime
• Fill pinholes, sand

• Prime
• Remove protective surgery tape

• Sand using procedure from previous chapter. Each sanding step moves out ¼” farther from the last courser step
• Locally polish area that has just been sanded using procedure from last chapter
• Give yourself a pat on the back because this actually worked, looks like it did before it messed up, and now you can add the final details to the mould before fibreglass lay-up!


Joel

[stark]

Your work just keeps getting

Your work just keeps getting better all the time Joel!!

Brian

[manowar]

Thanks Brian,
I am sure that

Thanks Brian,
I am sure that I am not just speaking for myself in that we look forward to seeing more of yours...

Joel

[manowar]

Hull chapter 5 section B group ii paragrah a part c

After the finish and repairs it was time to put the final details on the Jack mould.
Basically, I left stuff off like photo etch and the safety off because it’s easier to sand and polish without having those items on. Especially in the case of the photo etch because the cloth of the polishing wheel could catch a sharp edge of the metal PE and rip it off.
This time I’ve tried an all new technique in install the PE. I went out to good OL’ Canadian Tire (Best place in this cold nation to buy hand tools, and at the best price if your timing is right) and picked up a drill bit gauge. This a heavy gauge steel plate with accurate holes cut out so you can determine what size of bit you have. The application for this tool was to be place over my MBT markings and then use it as a guide and hull protector when roughing up the polished surface to accept adhesive and my MBT vent.


To apply the MBT themselves, I am trying something new and something I don’t know why I didn’t try before. All of the vents were taken off from the sheet and stuck on to a strip of clear tape. I removed the centers of tape with my Exacto knife. The clear tape allowed me to precisely stick the MBT exactly where it needed to be. Then a small drop of thin CA placed into the center where the tape was removed. The CA wicked below the whole MBT surface and didn’t come up and tarnish the hull surface which I’ve had problems with before...pretty slick trick!





Now, the Jack has a slightly different safety track path than the normal Permit boats have in that it does a dog-legged offset away from the weapon’s loading hatch, and I almost missed this detail but fortunately picked it up near the end. To put this off set in the new styrene strip track I drilled some 1/8 holes into a block of wood where I would put in some 1/8 rods. These represented the inside radius’ of the track. The styrene strip was heated up to malleable temperature with the heat gun and quickly bent around the pegs. Next, the hull was taped off leaving the spot where the strip was to be attached and roughed up using the Dremel. Then it was simply a matter of gluing the strip down.



It’s moulding time, but we’ve gone through the process many times before. The only thing of note here was that I decided to go with a “professional grade” epoxy surface coat as opposed to my own home brewed concoctions. I used BJB 1611 high temp black coat this time. I must say, when I first opened the can to part A I was really worried. The consistency of the stuff was like asphalt tar...and not fresh hot tar, but the stuff you’ll find in our roads up here at around -40 degrees (C and F). I actually broke a wooden tongue depressor off when first trying to mix it. However, I know from personal experience that heating epoxy not only decreases the viscosity of it but drastically decreases working time. Believe me, this stuff needed to be thinned so I took my chances. I ended up putting the can of Part A into hot water and stirred it up slowly as not to introduce air bubbles. As things turned out this stuff is actually really good, no air bubbles because the filler has been pre-mixed and that means no pinholes. The pot life didn’t end up being an issue though. No sag application let me put the stuff on really thick...I used the whole pint on the hull halves!

And here is the moulds freshly pulled off the plug halves. What you are seeing is wax paper on the flanges used for smoother texture than melamine board provides. This is to provide a nice surface for vacum bag tape. Also, the discolouration in the moulds is primer and PVA transferred from the plugs. All this stuff washed off nicely, but the plugs looked a little worse for wear including the safety track that came off and a few MBTs.


Now I have moulds, masters and repros everywhere in my house and garage, they are reproducing like rabbits.

Joel

[thor]

Joel,

I am glad to see

Joel,

I am glad to see someone else get brave enough to use BJB 1611. I have been using it since 1993 and have found nothing better. It is a VERY sensitive product and you must be very careful with it or you can end up with a real mess on your hands. The amazing characteristic of this stuff is that it is so thick and sticky that you can apply it over 1/8" thick with no trouble. Recommend a post cure with it for best lifespan and always recoat with wax after you pull a component....

Really nice work!

Matt

[manowar]

Thanks very much Matt!
I have

Thanks very much Matt!
I have no doubt whatsover that the stuff can go on to 1/8" because I think it was about that thick in places. I like it too, I'll use it again I would say depending on it production performance. I'll also see what I can do for a post cure..I might have to rig up a cardboard box and hair drier or something to do that.

Joel

[steveneill]

Joel this is your best

Joel this is your best to date. What a great job!

steve

[manowar]

Joel this is your best

Joel this is your best to date. What a great job!

steve

Yes, but man o man am I ever looking forward to getting to a new project, I love the Permit class but I would say she has run its course (only about 4 times!) We're almost there, just the towed aray fairng mould for the Jack and then its finito!

Thanks Steve
Joel

[steveneill]

I hear you Joel. I

I hear you Joel. I know the feeling.

Steve