Monday, August 30, 2010

Carbon Rowing Deck off the form!

At last I got to pull the deck off the form. Couldn't believe it!...I think it weighs less than a pound! It's not quite perfect....but with a little work it will be just fine... Ya hoooo!

Here it is mocked up with the seat, slides and vent covers in place.

Sunday, August 29, 2010

Laying carbon at long last

To lay the first layer of carbon the initial coat of epoxy needs to get to the perfect consistency.... sticky enough to leave a finger print, but dry enough to let go of the cloth if you pick it up gently. Given the summer temperatures we've had I thought it would take about 2 hours to get there after brushing it on. The weather has cooled this week though, and it took about 8 hours! Consequently I was laying carbon by halogen lamp and car headlights.

I have to stop right here and give a huge 'Thank you' to my husband who was my patient helper during this critical stage, and who has been unconditionally supportive throughout the whole project. The epoxy was taking SO long to harden up that I'd almost given up for the day.....but when I checked it at 9:30PM and it was perfect, Rick's response was, "If you're up to it now, I'll help!" We were out there untill 11:00PM. This photo was taken when we did the 2nd layer the next morning. Thanks, Rick!!

I am using 5.8oz twill weave carbon. Having never handled that type of cloth before I wasn't sure how easily it would bend around the contours of the form, but the weave is very loose and in the end it went on beautifully.

We unrolled it in four sections, working from the stern end to the bow. One successful trick was laying a sheet of clear vinyl on top of the tacky epoxy as a 'resting spot' for the glass roll, until we were ready to lift the vinyl out of the way and move onto the next section. I knew from building the form that vinyl and epoxy don't stick to each other, at least, not very easily. To explain this, I took a photo as we set up to do the 2nd layer this morning.

Here is the first layer, trimmed up around the form. Now I can't wait to pop it off the form to see the finished face!

Final smoothing of the form

Smoothing the form was a LOT of work. I could have been at it for months, but at some point had to call it good enough. I was using polyester resin (smoothing putty) for automotive work. After cutting out the two vent holes with a jigsaw the form was ready for applying PVA mold release agent. I laid on six layers using a HVLP air gun. The next step was to brush on a single thin coat of epoxy and let it get to the right consistency of finish to lay on the carbon fiber.

Sunday, July 25, 2010

Nailing down the mold......finally

Preparing the mold has been a LOT more challenging than I expected. The good news is I finally made a break-through today. Here are a couple of pics for now. It is so hot today that the resin was setting up in less than 2 minutes. I'll have to continue working during the early mornings.

Wednesday, April 21, 2010

This time it really worked....

After re-making the plug I cast another mold form. Finally I am happy. There are a few pinholes to fill and I have to mount it onto a base plate before I can use it, but it's the right shape this time. The inner face of the splash board is part of the mold too, which is much better than the original plan.

You can see by the flowers that spring has finally arrived. Temps are creeping back toward 30deg Celsius. The project is moving back outdoors for the next phase - carbon fiber!

Sunday, April 4, 2010

2nd Plug

Yesterday I rebuilt the plug and checked the dimensions. Much better. I built plug forms for the splash boards too and figured out how to support them solidly in position so now the entire mold will be cast all at once. I am much happier with this arrangement.

By then end of the day I my legs were tired from shuffling sideways like a crab up and down the narrow hallway working on the deck. I was counting my blessings though, as a cold wind was howling outside and there is no way I could have worked on it this weekend without having set up in our rental house.

This morning I worked on the hard seams - by that I mean the acute transitions between surfaces that are awkward to lay up using a single piece of cloth. I had the idea to use cloth and epoxy to make these transitions (duh...what a simple idea!), which I can make as smooth as possible before I cast the mold. I will use release agent on these sections to ensure that they don't stick permanently to the mold when I do finally cast it. Here are a few pics before I get ready for the big family dinner tonight. BTW - besides Easter, it is Rick's and my 30th anniversary of movin' in together! Cheers, Honey!

Publish Post

Saturday, April 3, 2010

Two strokes forward, one stroke back

Timing is everything. Yesterday I took the seat slides and foot-stretcher tracks that I had removed from my old double and set them into the new boat, along with the rigger from My Escape. I wanted to use the visual props to double check all the rigging locations before I proceeded with building the splash board forms. Damn. The seat deck is too far back, and not just a little....six whole inches. That is to say, I built what I had drawn, but the drawing had a design flaw. When she's rigged it would be impossible to get my hips in line with the pins in the catch position, which is more compressed than I'm used to at the catch, but is recommended for high performance.

I sat down with the drawing... again. The position of the pins is critical. Everything relates to that. That nice mold that I built....I took a knife to it.

I pieced the mold back together with duct tape to mock up the correct positions and sat back to analyze whether I'd got it right. If only I had done that exercise when I had the plug formed before I laid the cloth up. Ouch. Lesson learned the hard way.

Today's job: rework the plug and recheck the rigging again. On the bright side, I think I've come up with a way to make the hard corner transitions in the mold surface better than before. Simple idea.... I guess that's the benefit of doing it twice.

Tuesday, March 30, 2010

It worked!!

I pulled the deck mold off the plug and the vinyl peeled off easily, leaving a smooth finish!

The next step is build the splash board mold, which will form a base, and connect this part to it. That's this weekend's job.

Monday, March 29, 2010

Forming the Rowing Deck Mold

This sketch is a concept drawing of the mold for the rowing deck. Of course it is a negative so that when the carbon fiber is formed onto it, it will form a positive with the finished side against the mold.

To form the mold, you need to start with a positive shape, or what's called a plug. I debated building a plug, but then decided that I could use the boat as the basis for it. I used styrofoam board to form the decks and sloped transition surfaces, all held temporarily in place with masking and duct tape. The location of these are critical parts of the boat design.

The mold surface is going to be made of fiberglass, which I have to cast onto the plug. I got stuck for awhile trying to figure out how to ensure that the fiberglass mold would let go of the plug. I discovered thru experiment that fiberglass releases easily from clear vinyl, so I lined the plug with window-vinyl. Because it's see-thru, it is handy material for this work!

Then I laid 6oz glass over top and applied epoxy resin.

Today I checked the result... far, so good!

Sunday, March 28, 2010

RIP Kaschper Serial No. 79110

Today I stripped the hardware from my first scull - a Kaschper double that I rebuilt in 1998, and burnt what remained of her shell. I learned many things from this boat and she served me well. Like the Jack Johnson song says, "One goes out, one comes in." RIP.

On a brighter note, I also laid the base layer of glass for the mold for my carbon fiber rowing deck. Photos and details to come.....

I'm glad spring is finally here. S

Saturday, February 13, 2010

At it again!!

Got the wonderful idea (thank you Rick!) to continue building in our rental house while it is unoccupied. That gives me a head-start on the warm weather. I set up the strongback with negative forms and moved her in last weekend. Now I'm preparing the plug so that I can cast the mould for the rowing deck. Here are a few pics...