My First StarCraft; 1975 18' SuperSport

[classiccat]

Re: My First StarCraft; 1975 18' SuperSport

Yeah, this boat had 1 foot in the grave and the other on a banana peel. Good on you for saving her...

I think MarineTex and/or JB weld can curb and shore-up those corrosion areas...

I have been really happy with the way MarineTex has performed on some spot repairs I did prior to primer and paint...

That hull clean-up looks amazing BTW.

Thanks for the tips P! Marine tex is in my future here...I have a feeling that I'll need a few more boxes :facepalm:

Please do...at the very least I can point you toward the good ramps, but I'd love to do some fishing with a fellow tinhead! The Champlain fishery is getting better every year. Very good management from the VT and NY wildlife and fisheries folks. Worth the trip, IMHO.

Cool! My buddy goes-up once-or-twice per summer for smallies and pike. His uncle has a summer home on Hog island (how cool of a name is that!?!)

Bluefin, the idea behind sodablasting is that the soda is sharp, so it cuts into anything in it's way that's soft - i.e. paint, corrosion, etc. but it's also soft so it breaks on anything hard - metals, glass, etc. It's not supposed to damage the aluminum. With it corrodded like that... iono, I'm not a soda blaster ;p

At work, I run corn cob in my sandblaster - it isn't as efficient, but sand will peen steel, where the cob won't. Haven't tried it on an 'ol tinnie (yet ).

Thanks for the Media-Blasting cliff notes Yeonik! If/when I'm done restoring the SS, the exterior of my BlueFin looks like butt...soda blasting might be the ticket.

Ok... I prolly should chime in here as Jupiter I ended up at the scrap heap! BF --- I would suggest that you pick at those areas with a sharp pointed object or screw driver... make sure they are not about to be through holes. Corrosion kinda swiss cheeses the alum... I wouldn't want to see you go all the way though the rebuild only to find the hull cracks at the corroded spots. Just worth the extra check man!

Great progress though... keep it rollin'!!!!

Jim

Thanks Jim and Wow! I didn't know you had to chuck a hull!! Maybe on deep-pitted areas I add aluminum patches on the outside. The 2 holes that already corroded through need patches on both inside-and-out. The one one hole is right-up against the bow plate:

 

[classiccat]

Re: My First StarCraft; 1975 18' SuperSport

I really appreciate all of the help & support that you guys have given me so far!

I've been thinking about a process flow for treating a few areas with deep pitting.

Going off of memory, there are 4-5 spots where the pitting may be deep enough to warrant this...I believe most of it is shallow-enough where just some MarineTex spackling is needed.

Does this make sense?


The purpose for the patch is to provide a surface for the bucked-side of the rivet to land-on...I don't trust it landing on a marine-tex patch; bucking is a pretty violent process. Perhaps even large washers would be adequate?

An alternative to rivets would of course be SS 10-24 screws with nylock nuts + nylon washers...even more friendly to the marine-tex.

 

[barato2]

Re: My First StarCraft; 1975 18' SuperSport

problem with large washers is that finding aluminum ones may be tough, and i'd want to avoid adding any more potential for galvanic corrosion to that hull since you got a little less thickness to work with given how much has already gone away. i like your riveted patch idea, esp for fixes that will be below waterline

 

[InMotion]

Re: My First StarCraft; 1975 18' SuperSport

problem with large washers is that finding aluminum ones may be tough, and i'd want to avoid adding any more potential for galvanic corrosion to that hull since you got a little less thickness to work with given how much has already gone away. i like your riveted patch idea, esp for fixes that will be below waterline

Perhaps make your own... some reasonably thick aluminum, cut it out with a hole saw ---- nice and round with a hole in the center for the rivet or bolt! Just throwing some Canuk ideas your way man!!! :canada:

Jim

 

[classiccat]

Re: My First StarCraft; 1975 18' SuperSport

Perhaps make your own... some reasonably thick aluminum, cut it out with a hole saw ---- nice and round with a hole in the center for the rivet or bolt! Just throwing some Canuk ideas your way man!!! :canada:

Jim

^^^ I like where you're goin' with that Jim! I believe my hole saws will accept different-sized pilot bits.

 

[bob johnson]

Re: My First StarCraft; 1975 18' SuperSport

I say dont start adding LAYERS ontop of EXTRA layers.... you have your Patch...thats all you need...I would have the rivet heads on the outside of the boat!!! buck the inside..... if you really want or need an aluminum washer in case your hole inside is a little large.....Home depot and Lowes has aluminum washers in their rivet sections....... i think the largest dia ID i have seen is 3/16th"....with the outer dia about 3/8th" dia..... keep the smooth contour rivet heads OUTSIDE!!!!!!!!!!!! make sure you rivet close to the outer edge on the FRONT of ther patch..

bob

 

[classiccat]

Re: My First StarCraft; 1975 18' SuperSport

I say dont start adding LAYERS ontop of EXTRA layers.... you have your Patch...thats all you need...I would have the rivet heads on the outside of the boat!!! buck the inside..... if you really want or need an aluminum washer in case your hole inside is a little large.....Home depot and Lowes has aluminum washers in their rivet sections....... i think the largest dia ID i have seen is 3/16th"....with the outer dia about 3/8th" dia..... keep the smooth contour rivet heads OUTSIDE!!!!!!!!!!!! make sure you rivet close to the outer edge on the FRONT of ther patch..

bob

Rivet heads are on the outside of the boat...the corrosion that we're speaking of is on the inside of the hull.

 

[Grandad]

Re: My First StarCraft; 1975 18' SuperSport

I'm kinda partial to the patch idea and 5200. I wouldn't bother drilling through the deep pockets and riveting them. If the holes are that deep, there'll be a need for a patch over a larger area. I'd cut a patch to fit, ensuring that the patch curves intimately with the hull skin. Drill one 3/16" hole through both patch and hull near one end of the patch. Install a temporary nut and bolt in that hole, before drilling a second 3/16" hole at the other end of the patch. Put a nut and bolt in the second hole. Now that the patch can't move, drill a series of 3/16" holes for rivets near all the edges of the patch. Remove the temporary bolts and dress all holes to remove any offending burrs to ensure that the patch will still fit snugly against the hull. Slather the entire surface of the patch with 5200. Smuck it in place and put your temporary bolts back in. Install rivets working from the centre outward to ensure that there are no voids in the 5200. Replace the temporary bolts with rivets, smooth out the 5200 mess and take a break. - Grandad

 

[classiccat]

Re: My First StarCraft; 1975 18' SuperSport

I'm kinda partial to the patch idea and 5200. I wouldn't bother drilling through the deep pockets and riveting them. If the holes are that deep, there'll be a need for a patch over a larger area. I'd cut a patch to fit, ensuring that the patch curves intimately with the hull skin. Drill one 3/16" hole through both patch and hull near one end of the patch. Install a temporary nut and bolt in that hole, before drilling a second 3/16" hole at the other end of the patch. Put a nut and bolt in the second hole. Now that the patch can't move, drill a series of 3/16" holes for rivets near all the edges of the patch. Remove the temporary bolts and dress all holes to remove any offending burrs to ensure that the patch will still fit snugly against the hull. Slather the entire surface of the patch with 5200. Smuck it in place and put your temporary bolts back in. Install rivets working from the centre outward to ensure that there are no voids in the 5200. Replace the temporary bolts with rivets, smooth out the 5200 mess and take a break. - Grandad

Thanks for stoppin' by GD!

The good news is after testing all of pitting using a dental pick...nothing poked through; worst case ~ 1/3 of the hull skin (~ 0.025") remains...the 1 positive about having a hole that corroded completely through is that you have a reference :facepalm:

I'm still going to treat the pitted areas chemically, fill the pits with MarineTex and follow your recommendation on the patches/5200.

It's a good thing that I'm not in a hurry :lol:

 

[InMotion]

Re: My First StarCraft; 1975 18' SuperSport

That's good news BF! A dental pick!! That wasn't the Admiral's was it??? :facepalm: The ideas put forth sound good. I had one missing rivet on the Jupiter ---I just put in a standard rivet and then completely smothered it in 3M 4200. No leaks in 2 years. So what you are doing will really make sure it is solid and leak proof for decades to come!

J.

 

[bob johnson]

Re: My First StarCraft; 1975 18' SuperSport

. I had one missing rivet on the Jupiter ---I just put in a standard rivet and then completely smothered it in 3M 4200. No leaks in 2 years.

J.

OK guys what say we string this guy up from the highest tree for rubbing the ONE rivet in our faces!!!!!!!!!!!!!!!!!!!!!!!

ha ha ha.....just kidding IM!!.....lucky you!!

bob

 

[classiccat]

Re: My First StarCraft; 1975 18' SuperSport

That's good news BF! A dental pick!! That wasn't the Admiral's was it??? :facepalm: The ideas put forth sound good. I had one missing rivet on the Jupiter ---I just put in a standard rivet and then completely smothered it in 3M 4200. No leaks in 2 years. So what you are doing will really make sure it is solid and leak proof for decades to come!

J.

Thanks Jim! Nah...not the Admiral's dental pick. If you don't have a set of picks...recommend them. Great for working on motors, fishing reels...and now rotten boats :facepalm:

OK guys what say we string this guy up from the highest tree for rubbing the ONE rivet in our faces!!!!!!!!!!!!!!!!!!!!!!!

ha ha ha.....just kidding IM!!.....lucky you!!

bob

Jim's really tall so it would definitely need to be higher than my garage-opening gantry :lol:

I added 20-more missing rivets this morning...

 

[classiccat]

Re: My First StarCraft; 1975 18' SuperSport

Well guys, do you ever watch slasher flicks...ya know...the ones where the defenseless girl is walking through an old , abandoned house, (chasing her pet poodle perhaps?)...and hears a thud in the attic...where does she go next?

Let's pretend that the abandoned house is my StarCraft & the knee brace is its attic.

If you've been following this thread for awhile, you may recall that the bottom of the stern suffered some trauma...guessin' it was dropped onto a ramp & judging by the bent exhaust housing, the outboard was a temporary boat stand. The hull skin was dorked and some seam rivets were ground off...they're directly behind the knee brace.

Now you're probably saying to yourself, "Please don't remove your knee brace, please don't remove it...DON'T GO THERE MAN!!! NOOOOOO!"

now that would be a pretty boring movie if the girl used her brain and realized that there's no way the poodle can get into the attic...

jacked-up

 

[classiccat]

Re: My First StarCraft; 1975 18' SuperSport

ALOT more thick, white stuff:


It's tough to see it in the image, but the forward-port corner of the knee brace was pulling upwards and buckled the hull skin..same side where the upper tab nearly cracked completely off...and the splashwell was cracked...and the chine was bent...and where we have all of the stress cracks.


some deep pitting under the port-side tab:


...and some deep pitting on the transom skin...this where it buckled from being dropped. It looks like it even started to crack. This one's gonna be tricky to patch since everything is so warped/distorted:

 

[InMotion]

Re: My First StarCraft; 1975 18' SuperSport

Dropping it on a boat ramp and or a really weak transom board could cause that cracking --- some decent hull stress there from what I can see. Had a worse situation in Jupiter I... which as you know got scrapped.... but it was the right thing to do. I ended up finding Jupiter II --- which I looked for a really good condition hull after that experience!!

I think the question someone posed was "at what point is the hull not safe to bring your family out in". For me it was finding that the pitting was so far through that just poking at them resulted in holes. The alum around the holes was so far gone that just putting a screwdriver in the holes and turning it easily created a much bigger hole. End result: The alum was like swiss cheese. I scrapped it and went and got a good hull and salvaged all the bits I could.

I recount this story from someone who has gone down the corrosion path and from the fact that you may get to a go-no-go stalemate... keep in mind there are lots of good hulls out there. I just figured in the end my desire to save the boat to a distant back seat to the fact that I valued my and my families life a lot more than a few hundred bucks worth of aluminum. I don't know if you are at that point yet ---- may will argue one way or the other ---- but something to perhaps consider.

Hmmmmmm..................... it's certainly keeping things interesting here!!

Ps - Bob J --- ya you guys would need a realllllllllllllllllllllllllllly tall tree for my 6'4" frame!!!

Jim

 

[Yeonik]

Re: My First StarCraft; 1975 18' SuperSport

I hope I never get to see pitting like that in a hull (in person).

 

[classiccat]

Re: My First StarCraft; 1975 18' SuperSport

Dropping it on a boat ramp and or a really weak transom board could cause that cracking --- some decent hull stress there from what I can see. Had a worse situation in Jupiter I... which as you know got scrapped.... but it was the right thing to do. I ended up finding Jupiter II --- which I looked for a really good condition hull after that experience!!

I think the question someone posed was "at what point is the hull not safe to bring your family out in". For me it was finding that the pitting was so far through that just poking at them resulted in holes. The alum around the holes was so far gone that just putting a screwdriver in the holes and turning it easily created a much bigger hole. End result: The alum was like swiss cheese. I scrapped it and went and got a good hull and salvaged all the bits I could.

I recount this story from someone who has gone down the corrosion path and from the fact that you may get to a go-no-go stalemate... keep in mind there are lots of good hulls out there. I just figured in the end my desire to save the boat to a distant back seat to the fact that I valued my and my families life a lot more than a few hundred bucks worth of aluminum. I don't know if you are at that point yet ---- may will argue one way or the other ---- but something to perhaps consider.

Hmmmmmm..................... it's certainly keeping things interesting here!!

Ps - Bob J --- ya you guys would need a realllllllllllllllllllllllllllly tall tree for my 6'4" frame!!!

Jim

Yeah Jim, This is nowhere near that bad....now if it were a thin-skinned boat, it would be a different story. Thankfully this hull is 0.081" aluminum.

I went and better quantified the worst pitting and I've lost 0.045" max...so we have plenty left even in the worst spots.

I'm very glad that you chimed-in. If you hadn't, I might not have scrutinized it the way I have and may have had doubts after getting it back together.

I'm still going to assemble the floor so that it's modular/removable.

I hope I never get to see pitting like that in a hull (in person).

I hope you never do as well....although misery does love company :lol:

 

[bob johnson]

Re: My First StarCraft; 1975 18' SuperSport

the old wooden boats leaked ten times worse after sitting for a few months....water in the boat is a fact of life...they make bilge pumpos...neat things!!!! even if you carry 10 gallons home with you.....it should matter that much.,..it under the floor and you drain it when the boat gets on the trailer...... you need only worry about HULL intergrety......JB weld smeared over that area, all new rivets on the knee brace.....heck you can even add another knee brace, if you wanted......i bet 70 % of all the starcraft as old as your boat have that much pitting....
bob

 

[classiccat]

Re: My First StarCraft; 1975 18' SuperSport

This week, we had a few distractions for the task-at-hand....including a lightning strike that took-out our microwave's control board. $120 bucks later, one of the most under-appreciated, modern luxuries is back-in-action!

another random tip for stopping by my thread: To avoid buying unnecessary components (taking to an appliance repairman is completely out of the question) follow that troubleshooting diagram / flow-chart that's usually tucked-away behind the control panel. Most people spring for the nearest magnetron, HV-capacitor and diode at the 1st sign of microwave trouble. Also, not all temperature cut-outs are normally-closed at room-temperature

 

[classiccat]

Re: My First StarCraft; 1975 18' SuperSport

I cleaned-up the gunwale caps...and I tell ya, the pumpkin orange, corrosion and numerous dings are starting to grow on me...I think I'm gonna clean-er up and keep it just like it is!