1/96 Thor Sturgeon Build

[eckloss]

Over the past few weeks, Ive have some free time to get a little work done on a few boats. On the bench right now are a few Thor boats: the Seawolf, Sturgeon, and Permit. Just wanted to document some of the work I've been doing on the Sturgeon. Nothing really out of the ordinary here, except for the hull locking mechanism. You'll understand as the thread continues....

This is the 2nd Sturgeon I'm building. Bought this one a couple weeks ago as an unbuilt kit. Couldn't pass it up for the price. So if anyone is interested in a partially built Thor Sturgeon, let me know… I'll be selling the first one shortly.

Most of the photos speak or themselves. Pretty standard stuff…so I'm not going to take a lot of time and narrate the basic steps. But there are a few things I will explain in detail as the work continues.

First, the basic prep. The hull was washed down with detergent and a scouring pad to remove the release oils.

To better see the scribed details, a quick and easy trick I use is to saturate the areas with a black sharpie and let the ink dry for just a few minutes, then using windex and a scouring pad (CA kicker also works very well in place of windex), a quick and light buffing gets of the extra ink, leaving behind the highlighted scribe lines.

















To remove the extra indexing flange, I laid a 1/4" strip of brass along the centerline and marked the flange, and then simply cut away the extra and finished the area with a sanding block. I always also bevel the outside edge a bit when done.






Next, the cuts were made for the z-cut, and the flood holes in the lower hull were opened up. I hate this part. So time consuming!

[eckloss]

Re: 1/96 Thor Sturgeon Build

Ok, I have this strange obsession with getting seams perfect. Usually I get frustrated to the point of ripping apart what Ive done and re-doing it until its right. That being said, I decided to try out an idea ive been tinkering with on other boats. The Sturgeon will keep the standard z-cut, and usually I will make up a bow and stern indexing strip and secure the top hull with a single screw near the stern. Instead, what i've done is use 1/8" thick garolite (from McMaster…love this stuff!) and made bulkheads that will rest on either side of each cut in the hull, and that will be kept together with small magnets. The bulkheads provide extra rigidity to the hull, make a base for the mag-lock system, and provide a straight, square guide to correct any imperfections in the cutting of the hull. Its easy to slap on a little Bondo and sand down a perfectly straight cut line using the bulkhead as a guide. Before setting the bulkheads in place, they were sanded down at an angle to match the internal curvature of the hull.

In these photos, what vie done is complete the bulkheads and mag-lock for the bow. The cut bow section will later be secured to the upper hull. I cut out the bulkheads, drilled holes and tacked the magnets in place, one set sticking out a bit, the other set slightly recessed so that the magnets not only hold the sections together, but prevents them from slipping out of place. The inset magnets' holes were beveled slightly so that the magnets will easily slide into their target holes. I made a simple 90-degree rig to tack the bulkhead to and then attach the bow section. After a bit of sanding and filling, im left with perfectly mating hull sections. The same process will be repeated for the stern as well. No screws!

(please ignore the mess inside the lower hull. my first attempt at detailed torpedo tubes didn't go so well, so i re-filled the areas and decided to move on for now)

[eckloss]

Re: 1/96 Thor Sturgeon Build

Built the saddles for the 2.5" WTC from garolite.

More tomorrow...

[tabledancer]

Re: 1/96 Thor Sturgeon Build

Erich,
I am using a magnetic system to hold the upper and lower hull together in my XXI,but it`s a little different setup than yours,but still does the job.I`ve used magnets to do a lot of different things in all my boats.What type of glue did you use to bond the Garolite to the fiberglass hull?I had a little problem with the 15 min. epoxy that I have.I`m going to try using milliput to bond the WTC saddles to the hull.



TD

[eckloss]

Re: 1/96 Thor Sturgeon Build

SInce garolite is based on fiberglass resin, treat it just like its glass-on-glass. scuff up both surfaces (i use a cutting wheel to scar the inside of the hull along the lines where the saddles will sit), then tack it into place with a tiny bit of thin or medium CA. When youre happy with the placement, use a mix of epoxy resin and some microballoons or microstrands on both sides of the garolite. ive found that jb weld works pretty decent as well.

[eckloss]

Re: 1/96 Thor Sturgeon Build

i should also add when i say resin, im talking about the west systems resins, not the quick-setting junk from places like lowes or home depot.

[tabledancer]

Re: 1/96 Thor Sturgeon Build

Thanks,I have used J/B Wield also.I`ve used the quik setting and the slow set.Both are good and strong.





TD

[Rogue Sub]

Re: 1/96 Thor Sturgeon Build

I heard once that micro balloons weaken epoxy.. you guys ever heard that?

[eckloss]

Re: 1/96 Thor Sturgeon Build

im sure it does to some extent. but personally, ive never had it get weak to the point that it doesnt serve its purpose.

[thor]

Re: 1/96 Thor Sturgeon Build

Most fillers weaken an epoxy joint. Micro balloons is the worst material for making a structural joint or structural fillet. It is a very brittle material and extremely hard to sand. Use cabosil or fumed silica....it is a true thickener that sands easily...

[eckloss]

Re: 1/96 Thor Sturgeon Build

didnt know about the cabosil. ill pick some up for future projects. thanks, matt!

[Rogue Sub]

Re: 1/96 Thor Sturgeon Build

I heard that using left over fillings and dust from working on resin parts like alumilite parts makes an excellent filler for epoxy and CA. Tried it on CA but not epoxy.

[eckloss]

Re: 1/96 Thor Sturgeon Build

if thats the case, i have about a pound of garolite dust sitting under my drill press from drum-sanding all the bulkheads and such from the sturgeon.

[greenman407]

Re: 1/96 Thor Sturgeon Build

Sorry, but whats cabosil???

[greenman407]

Re: 1/96 Thor Sturgeon Build

Thor. I purchased micro ballons for the sole purpose of adding to 30 min. epoxy to make it easier to sand. If its not made for that purpose then what is it made for? Perhaps to strengthen a joint or to thicken it up?