Blueprinting a hull

**stickbait** · 09-22-2009, 09:20 PM

I recently found blisters on my hull while it was off the trailer. I need to repair these and fix some nicks, chips and chunks. I figured I would blueprint the hull while it is flipped over.

So if I was a hunter and wanted to kill 3 birds with one stone, where would I start?

What would you do if you were in my shoes?
Any tricks or tips you've learned from experience?
Any good reading material you think would be helpfull?

Any and all help is greatly appreciated. i am actually looking forward to getting my project boat moving.

I realize i am asking for a lot of typing, but I know you guys are the ones to ask

Thanks!
-Josh

If you need pictures of anything let me know and i'll post them asap

**XstreamVking** · 09-23-2009, 07:09 AM

Find the center of the trans. and start measuring out from there. Look for any differences from one side to the other. Use a good straight edge and check for hook and rocker. Once you inspect the bottom, decide if the surfaces are un-equal or there is a bad hook. Some hulls have a small hook built in. Do a thread search here and see what a blueprint job can do for you.... Start by seeing if it is necc. to even go there.. Lots of nasty work if hull needs a re-shape..Very tedious and time consuming. My Hydrostream wasn't very bad and it took allmost a week of filling and grinding,sanding and spraying to make it perfect.....You will need to make very accurate mearurements, so have lot's of light and dont get in a hurry...Go 6' ahead of the transsom and tape off a V from the trans corners to the 6' mark on the keel...Check out my V- King re build, it has some pics of my blueprint process.. Have fun ....

**OFFSHORE GINGER** · 09-23-2009, 11:11 AM

Over the years i have done more then my share of blueprinting bottom's from adding strakes for more lift and different pad's while working at Skater and other . I have to say that the very first thing i would do is follow XstreamViking's advice and put a straight edge on the bottom of the hull and if you do have a hook most likely you are scraping speed .

**ar300johnson** · 09-23-2009, 02:57 PM

I had my boat bottom done last year. It had mostly hooks , but I found a section that had a rocker. It was a mess. I took the boat to Al Miener at Elite Powerboats outside of St Louis. He did a great job. Not only was the bottom totally straight, but all the edges of the strakes and the end of the boat were sharp. It changed my boat from a porposing pig to a great handling boat with no porpose or chine walk. It also runs 7-8 mph faster. This was the best money I spent on my restoration project. Just remember: straight and sharp.

**stickbait** · 09-23-2009, 06:36 PM

Thank you guys for your responses, I really appreciate it. Thanks for helping out a noob!

Ok, I have a few questions.<O

</O

<O

</O

My hull is red, what am I filling the low areas with? Marine Tex<ST1

</ST1

? When filling the low areas, how rough do I need to make the fiberglass for it to bond and is it ever a good time to take a little more low out first before filling so the patch is thicker and more durable?
<O

</O

<O

Do they make a color matching kit or will I have to have it painted?

Since I have other fix’s needed should I paint and gel-coat the whole bottom fresh and only rough up the back with 400 grit?<O

</O

<O

</O

I have chips and chunks I need to repair, mostly in the strakes; they aren't very big but obviously need to be addressed, should they be filled with the same compound as above?
<O

</O

<O

</O

As far as sharpening the strakes, how far up from the back of the boat do you generally go?<O

</O

<O

</O

Any tips greatly appreciated! I plan on getting some pictures up soon!
<O

</O

-Josh

**OFFSHORE GINGER** · 09-23-2009, 10:48 PM

Josh just curious have you taken a straight edge to the bottom of the hull yet and might i recomend a filler for marine use above and below the water line that Skater uses and most other Boat Co's that i have worked for and it is made by ADTech Plastics systems www.adtechplastics.com Josh you will need to find out what areas need to be filled then sand , and the general rule of thumb is if the area that you are working on is low , fill and if it is high , sand . Josh , i always fill and sand blocking out the bottom to make sure everything is straight and glass over everything with 2 layers of 4 oz cheese cloth , sand & prime with Dura tec and putting enough primer on the strake edge's so i can sand them to a very sharp edge along with dialing in the bottom once more by blocking it out and making sure everything is straight . Josh this is something you can do yourself and besides what do you got to loose by trying .

**gutlassracing** · 09-23-2009, 11:11 PM

What are you guys meaning by hooks ?? I put a straight edge on the bottom of my stv and the center of it about 4 foot from the transom it starts getting alittle light between the straight edge and the hull of the boat and it gets greater till about 1 inch from the back of the boat then touchs again .. When I say daylight it is about .030's but I also heard this could help with alittle lift also .. This has been added since the rear 4 foot setion of my boat is in primer and then was sanded so somone has been under it and seems to have done this on purpose .. Any input ?? I am also going to flip mine this winter and work the bootm to fill a few nicks and fix a few scratchs but I am wondering if i should leave the pad like it is for the little lifting action it is prolly doing ???

**XstreamVking** · 09-24-2009, 06:48 AM

Some hulls have a little hook, for example Allisons.Find some one that has had some experience with bottom specs for an stv. At long as it is the same from side to side, thats the most important thing. Before changing get some good info. On a boat that runs 100+ even 30 thou. can make a big change...As we are all finding out, change is not always a good thing....

**stickbait** · 09-24-2009, 08:04 AM

what am i filling the low areas and other gouges with? Marine tex?

**OFFSHORE GINGER** · 09-24-2009, 08:45 AM

Originally Posted by stickbait

what am i filling the low areas and other gouges with? Marine tex?

Josh i would fill in the low areas ( hook ) and chips with a good quality filler like i mentioned in post # 6 this filler mixes like a Bondo with a cream hardner / filler and is hard to sand in minutes . Josh i personally woud skip the idea of using Marine Tex .

**oldskier** · 09-24-2009, 09:12 AM

Ginger suggested this.

"i recomend a filler for marine use above and below the water line that Skater uses and most other Boat Co's that i have worked for and it is made by ADTech Plastics systems www.adtechplastics.com"

I used this:

http://www.jamestowndistributors.com...ct.do?pid=6515

The 3m vinylester filler was suggested to me by John Spaeth of Hydrostream-Canada.
It works very well and it sticks well to old polyester. ( It sticks well to ANYTHING I suppose, I got a speck of it on my Imron paint and I'm afraid to pick it off, it's ON there.)
The epoxy fillers would adhere even better than that I would assume, but it would require that anything used over it be epoxy. You shouldn't use polyester or vinylester over epoxy. I.E, epoxy on poly or vinyl-OK, poly or vinyl on epoxy-NOT OK.

A lot of guys would use kitty hair, but the texture is rough and it is just polyester with chopped fiberglass strands. I might use it to fill a deep area, but if it's THAT deep, some rebuilding would be better, I.E. some cloth or mat and resin.

This is a DEEP subject here, materials are something we argue over every day on this board. Ginger is an expert, so is AFR (Scott) and Capt. Insane-O. There are several others, I am an amateur, but the 3M worked well for me and making sure you have a rough clean surface to put the filler on is more important than what material you use. Automotive fillers are NO-NO!

Bernie

**stickbait** · 09-24-2009, 09:22 AM

Awesome guys, I totally missed that OG on the earlier post, or just wasn't thinking this morning, I will get some ordered ASAP

I will keep you all posted, thank you very much for the help!

**Riverman** · 09-24-2009, 09:28 AM

One of the things that helped me a great deal was a two foot long piece of rectangular aluminum extrusion I found. I think it was 2X3, I used double sided tape to adhere sandpaper - this tool made it real easy to get the surfaces flat and straight.

**Jimboat** · 09-24-2009, 10:03 AM

stickbait - you've got some great advice in this thread for your "blueprinting" project. You're definately on the right track. One of the most productive things that you can do to make your boat go faster and handle better is to "clean up the bottom running surfaces". Much of what influences the way that your boat behaves comes from the conditino of these running surfaces.

There's no short-cut to getting your bottoms perfecd. A long straight-edge will be your best friend..that and lots of elbow-grease! the flat parts of your aftmost running surfaces should be "dead-flat", with no waves, chips, bumps, etc. The straight-edge will allow you to see any hook or rocker that has developed in your running surfaces, and these should be taken out (if they don't belong in the original design). The trailing edges of any surfaces, including strakes, should be very clean and sharp.

These guys have all been there...they've got some great advice for you! keep us posted on how your project boat is coming! And show us pics as you go!

**OFFSHORE GINGER** · 09-24-2009, 01:23 PM

Originally Posted by stickbait

Awesome guys, I totally missed that OG on the earlier post, or just wasn't thinking this morning, I will get some ordered ASAP

I will keep you all posted, thank you very much for the help!

Josh i Apologize for not giving you More product Information . josh the filler i would recomend is Ad Tec's P - 77 it is a high heat resistant filler/faring compound and is good for use above & below the waterline and is good for use with Vinyl ester , Poly & epoxy. Josh , i think the price is around $57 dollars a gallon but i could be wrong and the reason i like it so much is because it is very easy to sand and can be used with any type of resin even Epoxy. Josh you can either order on line or call there toll free number .

User Tag List

Thread: Blueprinting a hull

Thread Tools

Display

Blueprinting a hull

Posting Permissions