Vacu-forming machine

[Kazzer]

I guess it's an RCABS thing. It leaks! Is it because of the bladder, the lines to it, or the numerous flanges/plates/o-rings bolted onto the thing? I'm not sure where to start.

Anyhow, it can sit there until I become inspired to tinker. I have other things to do and my test tank is covered over.

[Subculture]

This system is really no relation to RCABS, other than it uses a bag.

If the bag is leaking, then someone has probably been a bit rough with it. The geared pumps used in the boat are running on close to half volts, and therefore the pressure they can make is somewhat restricted. So I think it's unlikely the bag has been split by over enthusiastic use. Plus the bag is housed inside a cylinder of it's own, which helps constrain it's proportions well.

Anyway, easy to replace the bag.

[Kazzer]

I suspect it's either a pipe connection or an o-ring seal on the Plexiglass face plates. Maybe I don't have the bolts on that plate tightened well enough. I know it was fiddly getting into the unit to install batteries.

You're making me get the damned thing out to look at it. I want to finish my M1 first! Leave me alone! :-)

[Subculture]

The rods on holding the end caps on are sealed on the inside with pieces of silicone tubing. Bit of an unusual arrangement, but it seems to work.

The easiest way to spot leaks is to mix up some soap suds and water, brush it around all the areas that could possibly leak, and blow air into the module when it's buttoned up. Any leaks should make themselves quickly apparent with bubbles.

[Kazzer]

As I'm waiting for the electrician to sort out the heater wiring, I've made a start on getting a plug together so we can get cracking once we're up 'n running.

I decided to use the X Craft spare model I had to become the first project. After all, I have all the appendages molded.

1st problem is the bed of the vacu-former is 26" x 22", so I have to form this big boat in sections. Out with the Dremel cutting tool and the dissection begins.


I'm going to mount these pieces on a ply board and fill them with foam, then make a clean edge on all the cuts. I need the styrene to form a square flange so that edges now have weldable flanges. These will be bulkheads and strengthen the hull - I hope!

[trout]

Mike, it looks like the way you cut it, it can be assembled with the "Z" cut already built in. Is the bow going to be seperated like the stern is? Was it awkward to cut up a good model?
i am looking forward to your first pull!

[Kazzer]

Yes, the Z will already be there! I haven't cut the bow yet, will do that later this week.

As for cutting it, I started with a Japanese saw, but it was difficult to control and kept running off the line. (I know a poor workman blames his tools), so I reverted to the Dremel. That did the job in seconds. I already have a perfectly good model so this didn't cause me too much heartache.

[Kazzer]

Here is one section of the model. I capped the ends with cardboard and soaked it in resin. Then filled the bulk of the void with wood. Finally, I filled the remaining voids with epoxy/sand slurry. I had to place a weight on it because the wood floated up.
The ends needed a bit of work with bodyfiller and sanding, but overall I'm pleased with the result. Five more sections to go. A new part for the vacu-former is on order and should be installed on Monday.

[He Who Shall Not Be Named]

I see a 1/72 SKIPJACK lead-weight mold .... I WANT MY WEIGHTS, WHAAAAAAAH!

[Kazzer]

I filled the hull sections with wood and ALumilite 610 foam. They also have another foam 320 but this doesn't have the compressive strength of the the 610. Just so you know, the 310 means 3lb foam expanding to 20 times, and 610 = 6lb foam expanding to 10 times.
They both cost the same, but what you lose in strength, you gain in volume.


On the right, two sections are screwed and glued to the pegboard, which has been cut to the size of the Vacu-former.

I'm not sure if I should coat the plugs in wax or something. Any advice? Matt Thor? Does this sound OK?

[Kazzer]

We're slowly progressing towards our first pull on our new vacu-former. We've had a couple of set-backs, mainly a circuit board that fried during installation, which has taken a couple of weeks to get a new one, and the 440 volt 3 phase converter installation.

But, we're almost there!



Here is the platen and the frame that holds the plastic sheet. 24" x 28"




The little black box, lower left, is the 220v - 440 3 phase convertor. (This stuff just gives me a headache)

Anyhow, We'll be doing something fairly simple initially, and as soon as we've mastered the procedure, lets get some models out of this puppy!

[MThor]

Mike,

Did you follow through on any of the hints I passed along to you?

Matt

[Kazzer]

Mike,

Did you follow through on any of the hints I passed along to you?

Matt

The new part will be installed on Thursday so I hope we can try a few things then. Thanks Matt