Vacuum bagging

One of my next-boat possibilities is available in three layup options, including vacuum-bagged carbon. The vacuum-bagged option was recently added, so I assume the builder is fairly new to it. I have a vague recollection of a thread some time back in which somebody said something about vacuum-bagged layups coming out either perfect or unusable, but I can’t find the reference now. For those of you who know something about this stuff, am I remembering right? Anything in particular to be aware of with a builder who’s new to vacuum-bagging?

Yuo may want to check the
Royalex thred ,seems they know about the process.

Sorry to differ but totally different
Vacuum bagging is applied to composite boats. The idea is to get rid of all the extra resin which does nothing but to add extra weight. Qcc, seaward, CD all vaccuum bag. I like it!

Vaccuum forming applies to plastic boats, which I know very little about. It sounds like an alternative to rotomolding, which has become pretty good these days. Then again it may be how the eddyline carbonlite boats are made and they are fantastic for plastic boats.

"For higher quality, we have to suck!"
If they’re a good company, they will check their vacuum bagging products carefully, and they won’t push them out the door if they aren’t right.

Actually, vacuum bagging may have rather small advantages in shops where their hand layup is careful and obsessive-compulsive. But once they get the process down, they can save time and money and return value to the customer.

Proper vacuum bagging not only removes excess resin and pushes the cloth layers smack up against each other, but it can make pinhole gaps in wet-out less likely.

What’s proper?
What are the potential problems? How do you tell the difference between proper vacuum bagging and something you wouldn’t want to take out on the ocean?

Thanks for the input.

No baggies at QCC
According to Phil at QCC they do not use vac bagging - All laminates were hand-laid, at least at the time of my boats manufacture (summer 2001).


If you respond now, I’ll bet ya ten

– Last Updated: Jan-19-04 9:57 PM EST –

bucks on that. I've Owned a Q500, a caribou, an romany explorer and a couple of other boats. If anybody can get the strenght to weight ratio and the super smooth interior finish of QCC without vaccuum bagging I would be pleasantly surprised. $10 is not too much for me to pay for a pleasant surprise, and not going to hurt you I hope. So what do you say?

One last contention, just because you vacuum bag, doesn't mean your boats are not hand laid.

(EDit the above sentence is very wrong).

Soon we will know and if I am wrong about QCC you will at least have my aknowledgment that you were right and I was wrong.

The issue is not with the vacuum
bagging, but with the cloths and resin used. There is an urban legend running around about how Bell Canoe tried vacuum-bagged epoxy on a batch of boats, and supposedly had serious problems. Bell usually uses vinylester resin and hand layup. Their problem was not with the vacuum bagging, but may have been with some unexpected incompatibility between the finish on some fabrics they used and the epoxy. (I don’t know whether they also used heat curing.)

You can use either epoxy or vinylester resin with vacuum bagging. As for cloth finishes, all glass cloth must have a finish which is compatible with the resin. And glass fabric finish must be fresh. Kevlar cloth has no finish. Polyester cloth will form a tenacious bond with vinylester, but just an ordinary strong bond with epoxy. But all this is irrelevant to vacuum bagging.

When you go to look at any composite boat, if possible, get it inverted out in the sun so the light pours through the laminate. (Won’t work with a lot of carbon cloth because it will block the light.) See if you see areas which look resin starved. Next put the boat on the ground and see if there appear to be resin puddles where the builder didn’t work out the resin. Of course, in a vacuum-bagged boat, you won’t see puddles or drips. If you see no, or almost no such flaws, that’s all you can do. You can’t take a club and whack the boat. If the boat later shows unexpected failure, it won’t be because it was vacuum bagged, but because they chose the wrong cloths, the wrong resin, or both.

So you have to risk the purchase. If the builder is one who will stand behind their mistakes, don’t worry about it until you have a problem.

Peter, I’ve seen composite boats with
smooth, puddle-free, drip free, strand free interiors which were NOT vacuum bagged. It just takes normal care by people who regularly lay up boats. I have both vacuum bagged and non vacuum bagged boats with beautiful interior appearance, though an old Noah with beautiful work had some pinhole leaks because Noah worked to hard getting the vinylester resin out of the cloth.


Prijons plastic boats are wacum bouild.

Take a look at there home page.


who’s the builder?
i bet you’re getting a cool new ski. i’m jealous. vacuum bagging is totally standard on high end skis- all the builders do it now, I think. I’ve never heard of any problems as long as you stick with a reputable builder.


Well I was wrong

– Last Updated: Jan-20-04 10:35 AM EST –

and Jim was right!

Had a reallly good talk with Steve at qcc today. today. He does not vacuum bag, he says the quality interior finish and strength to weight ratio I noted comes down to the 20 years of average experience fo the guys and gals in the plant. He noted the cost of the consumeables, bleeder, release film etc.

The 700 becomes even more delicious to me. but I will not buy one till I lose a bit of weight. Time to jump on the e-trainer now! ;-)

Looking at Fenn
The U.S. builders all use the bags, but it looks like Fenn just started. He’s been at a little bit of a weight disadvantage. Ocean Paddlesports is offering the bagged boat as a special-order item at about the same weight as the U.S.-built boats (24#). The non-bagged carbon layup is advertised at 30#. That’s a significant difference but not a huge one, so I’m trying to decide whether it would be worth the additional cost and the guinea pig factor with a process that’s new to them.

I still have a couple of other decisions to make before I do any ordering, anyway. My hipbones are slightly wider than the bottom of the Mako seat, so I’d have to pad up a little. I think I could learn to live with the stability, but I’m a little worried about re-entering in the bouncy stuff if I take a swim. I’m not going to make a decision until the end of the season, so I’m just gathering information for now. Always fun to think about the next boat. :slight_smile:

Why not lose the weight IN the 700?
and watch it go faster, and faster…

as you get lighter, and lighter…

QCC & vac bag
Yeah, I talked to Phil at QCC last year when I was contemplating adding some D-rings for an under-deck bag. One of my queries was about vac bagging, and he stated that they used hand-laid laminates. Over the course of my paddling career I have built or helped to build quite a few boats (WW kayaks and C-1’s), and yes, getting a well-saturated but puddle-free laminate is not easy. Kudos to QCC’s elves.


It’s all about the dollars to make it
work. The consumeables are expensive. Their process is so good that the weight savings would not be worth the extra expense to enough paddlers to make it go! I like the 700 though I am not part ot the cult any more. I’m sure that Steve, Phil, and the folks at QCC are smart enough to run some numbers on this; absolutely no doubt! Steve assures me that they have looked into this in some depth.

weight issues

I just got the Mako 30# millenium from DeAnne and Patrick. Unfortunately I can’t paddle it just yet. but I did lift it and it was lighter than the Mark 1 substantially. What do you think you are going to gain by going 5 lbs lighter? I tormented myself with that question and then opted out for a less cost over less weight.

I have always thought and been told that i was wrong that every little bit of weight adds up against you. This may not be entirely false, but I don’t think I’ve ever lost a race, because my boat was 5 pounds heavier than the other. In the long run, if cost is an issue, than as afolpe told me:

wrt the ski- personally, i would save $ and deal with a 31 lb boat (that’s still damn light) rather than spend up for the lighter one. realistically, if someone beats you, it’s not going to be because their fenn is 5 lbs lighter.

If cost is not an issue, then you might be mentally 5 lbs faster in the lighter ski. Have you paddled the Mako yet? what do you think?

At 30 lbs my cartopping issues of heaving around 50 pound boats has truly come to an end.

I agree
The 5# isn’t really a big deal. Other things being equal, I’d prefer lighter, but 5# is basically the weight of a full 2-liter Camelbak, and I sure can’t tell any difference in performance between when I’m carrying my Camelbak and when I’m not. In theory, I believe that a lighter boat should have an advantage in surfing conditions because it will accelerate easier onto a wave. In practice, the total displacement is mostly paddler, not boat, so I doubt that 5# is going to make a difference, especially for a hacker like me.

I’m more interested in which process will produce a better layup, since I’d like the next ski to be a little more durable than the current one. I know a lightweight layup isn’t going to last forever, but I don’t want it to ding every time I accidentally bump something while I’m loading or unloading.

I paddled Twogood’s version of the Mako briefly on flat water, but I haven’t paddled the Fenn. I’ll probably set that up sometime in the next couple of months. I liked the way the hull felt on the flats, but getting in and out was a little dicey–my okole just barely makes it into the seat. I’m sure that would get somewhat easier with practice, but I don’t want to find myself drifting to the Marquesas while I’m practicing.

both my ski’s have a gel coat. The Mark 1 is built so solid, that there is no oil canning on the back deck behind the seat. It has a deep seat and you feel strapped in, even with no strap. I do put a 1" pad to raise me up a bit for comfort. With the gel coat however, a ski can always be repaired easily. I have let it roll up the beach when coming off a difficult landing, and it has survived rather nicely.

The virtues of vacuum as opposed to non vacuum might be great, I can’t tell, but it would seem to me, that throwing a little kevlar in the mix, would make for more strength. Carbon being light and rigid, but inflexible. Kevlar being strong, less rigid, but more flexible. I had a QCC boat laid up with Kevlar in critical areas for peace of mind.

Another thing to consider with skis leaking is they be pressure released. If the water is colder than the air, then the internal pressure wants to suck water into the hull. All the Fenns come with a straw now for this.

hope this helps, either way should be a terrific boat. Just thinking out loud, but did you try the MArk 1? for hawaii’s Portlock wall and bigger conditions, it might be a compromise on flatwater, but power releaser when the going gets big. With its rockered bow, its less likely to plow into the back of wave you are chasing downwind. It does give up some speed to the Mako on the flats.

Different sort of ding
My current ski is a carbon sandwich over foam. It’s plenty strong and stiff, but the foam will dent from a fairly light bump. Any layup without the foam ought to solve that problem. It will give up a little bit of strength in the water, but my experience with this one makes me think that’s a reasonable tradeoff. That experience probably also makes me more sensitive to layup qualities than I would be otherwise, which is the main reason I’m curious about bagged vs. non-bagged.

I did ask the Hemmens about the Mark 1, but they don’t have a demo in Hawaii yet. I’ll probably wait to try that if I can’t get comfortable with the Mako. The Mako does seem to have some speed advantage in pretty much everything if you can handle it, though. Realistically, it doesn’t matter for somebody at my level, but I’m still kind of inclined to go for it if I can make the seat fit.