New Design Temporary Female Mold Build Help...

If you hand laminate; your boat will be about 30-40% resin heavier than needed.

The resin-glass ratio will be high and the build will be substandard. More resin is not desirable.

Despite the potential debate; running low resin in hand layup is very difficult, moreso for amateurs (like me and you).

A home builder should be working to exceed production builds; not building junk.

My work is going well with wetbagging and I am wasting about 37% of my resin. For example, a 83 ounce piece of glass is wetted between 102 and 106 ounces of glass. The final epoxy in the part is about 66 ounces which means about 40 ounces leaves the part during vac. People here might laugh at my excess resin, but it has to be in the bag in 70 minutes no matter how large; and I am doing it; not them.

In Rob Denney’s method; resin losses in infusion are much less. He might have some numbers that will blow you away.

My resin costs about $0.63 per ounce; so I am pitching $24 in resin for that part. My larger parts require help to get it all in the bag in time.

Infusion starts with the bag closed and the starting resin amounts are closer to finals. The losses with infusion I don’t know, but maybe 10% or 7 ounces or $4-5 bucks. And you can work alone; not so in wet bagging. Perhaps my example is doable alone, but not big parts.

Hand layup will result in all the excess resin in the part which is a quality problem.

Or, if you try to build at the rates I shared; you will build garbage.

The reason to build in plywood is the glass; this resin amounts can be less; so you have less resin to add weight to the boat.

If you want to start small; budget some money and learn infusion. Build a dinghy or small foam 12’er.

Rob’s advice is very sound.

If I could go back and redo things; I’d buy 10k infusion resin instead of laminating resin and learn infusion. A lot of labor and resin goes into wet bagging to produce a great product. My only issue was not knowing the resins were different.

 

Rob,

All great information... a lot to chew on.

Thanks,

 

What do you consider wetbagging? Do you have any photos of your setup? Could I not just vacuum bag my parts in the female mold? I would gel-coat cure, hand lay-up the glass and then bag the mold to remove the excess resin. After this sets, add the hand laid core and interior lay-up and bag again. Is this not how production hulls are made? Or is everything now injection infusion.

For injection infusion, if the hull parts are vertical how do you lay-up the glass,core,glass and then bag? I would think that the glass would not stay in place while waiting on the resin. My only concern with table infusion is infusing the panels and then having to be in a hurry to get the panels into the mold. I guess that I would have to filet and tape the seams of the panels together? How do you ensure that there is enough glass/resin at the panel connections? I am kind of old school mentality when it comes to glassing.

I would have to see someone actually create with table infusion method for me to be comfortable with this idea. I like the idea of having the female mold that you can see and tweak prior to mixing the resin. I fear that making a panel on a table and then having to contort it into a jig might be an issue. I guess that you can cnc the core, as you can ply? and then you can dry fit all the panels... what about the ends of the panels? Will they grown outward as you add the thickness of the resin and glass? Does the glass have to exactly match the core? Do you place the panels in the jig when wet or do you let cure? Some of my panels will be tortured, how does this work with table infusion?

It would appear that I am chasing a rabbit...

Anyone have any ideas where I can see the different processes live and in action?

Thanks,

 

You Tube has just about any method imaginable.

 

You are not old school mentality, you are properly clueless.
So let'start with some basics. What resin type do you want to use? Polyester, vinylester or epoxy? Do you want gelcoat or will you paint the hulls? Is it a cored construction? How much fiberglass does the laminate have? Is it profesionally designed or not?

Today most production boats are infused in one shot using a female mold. Why? Because you do not have to hurry, you do not handle wet fiberglass, you do not have fumes and the finished product is better. You handle resin only once, when you mix it in a bucket. All other steps are performed dry and can take as long as you want with as many interruptions as you want. After the resin is sucked up you clamp the lines and that's it. After the prescribed curing you can release vacuum and debag at will.

How does the dry fiberglass stay in place in the mold? Spray adhesive from a can. How do you infuse both sides of a core in one shot? Perforated core. Do you need to CNC cut the core? No. Foam can be cut with a kitchen knive, balsa with a jigsaw but both can be CNC'd if desired.
When infusing flat panels you do not use a mold. After the panel has cured you take the panels and either bend them or torture them to shape over a simple jig. Will they take the required bends? It depends. If the boat is designed for it then yes. How do you join panels? Either rebates or butt joints with thickened epoxy and hand laid fiberglass. How do you asure enough fiberglass at the joint? Scantlings.

 

There is not sufficient time for you to wetbag a full mould, perhaps with a crew of like 8 people trained in pleating and wetting out. The epoxy would set before you got the wetout done, let alone the layers and closing up. Even with an oven type epoxy; you only have 3 hours, so alone, forget it. The glass used over foam is generally thicker stuff and wetting out over prelaid glass is VERY time consuming. Imagine the dread you'd have after realizing you can't get the entire hull in the bag and closed, epoxy is running, areas are dry; a few places need cutting to fit.. Some of the epoxy starts to cure and the rest is dry and the entire boat is trash. Or you manage to bag it, but has 6 leaks through the hull you missed. It has happened to people.

And, yes, to some degree you are chasing a rabbit because you have put very difficult parameters on the project without understanding options first. Rumars post, while a bit offensive, cuts to the point. Before suggesting slow, small, alone, foam, hand; you need to understand methods. The best answer to your original post is No.

I am building a flat panel boat, so all the panels are made on a table with vacuum. Then they are bonded together at the boats length or as needed with tapes by hand. The tapes are the only part of my build that is hand laminated. The big panels are 32’ long. The vac table is 400” x 49”; not what you want to do..

I was kindly explaining to you that infusion would have been a better way to do my panel work. If you insist on working alone in a small space; the only practical option is to either wetbag or infuse the parts or use plywood; hand lamination of foam will result in inferior work. This might bring about some debate, but in general, I am correct.

As for the rabbit; you can build a hand laminated panel, but it isn't the quality that it can be. It will be heavy and weaker than a wet bagged or infused panel. Finding a designer to agree is another hurdle.

And if you are going to use smaller panels, then infusion is really the best way to go because you will still be using a lot of hand lamination for panel bonds.

I know about a guy building small like you in his garage, but plywood. Generally, you can use less glass than foam. He made the mistake of using polyester and his entire house gets the odor and was sickening to his wife.

I believe it is a Woods Flica; I can double check, but the builder is in Vermont; haven’t seen lots of progress lately with winter and stink.

All segmented until ready to piece together. I think it is contour foam bottom and ply sided. If you’d like, I can find a link to build photos or you could contact Richard Woods.

If you insist on all foam; then hand laminating is not a good idea from my knowledge of the subject.

 

Here is the boat in a female jig.

Here is a full panel on the table. The vac lines are no longer placed on the part; this was a rookie error. See all the resin in the breather media? That is what you’ll leave in a hand laminated part, weakening the panel. With infusion; the excess is not used.

Can’t build this boat in a 8x12 room.

 

The restriction of a 2 car garage changes things, but only a little. Infuse the small pieces, but include self aligning male/female joins to join them together rather than heavy, leaky, space wasting bulkheads and bolts or butt joins that need to be faired inside and out.

You don't need a suit, mask or breathing apparatus (boat building is meant to be enjoyable!) and can infuse in high humidity. If you leave the vac bag on overnight under pressure before you infuse, you will remove all the moisture from the glass which further improves the weight and quality of the laminate.

There is no "epoxy preparation" and "nothing to clean up" with Intelligent Infusion. The laminate and core are cut the same as they would be for hand laminating, then laid in the mould. There is a bit of extra work gluing the sheets of foam together (hot melt glue) and attaching the cloth to the vertical surfaces, but probably less than labelling, rolling and stacking the glass for wet laminating. The vacuum plumbing needs to be laid in the mould. This takes a while the first time, but is quick from then on. The bag needs to be applied and sealed, but it is far easier to do this with no wet, rapidly curing laminate under it. Then you mix the desired amount of resin, stick a hose in it and watch the atmosphere wet out your job. Perfectly. Misers like me mix ever smaller batches of resin until the job is finished and waste very little. A length of 10mm 3/8" spiral and 2 x 100mm/4" wide pieces of shade cloth, both filled with resin. The resin used will be near enough half the weight of the laminate. Hand layup done perfectly (rare) will be double this. Plus the waste in the tools and containers, on the floor and on your clothes.

The time, hassle and material saving post infusion is equally dramatic. There is no cutting or grinding of cured laminate, no taping and filletting (24 x 10m lengths = 240m, just to join the hulls and decks for Fallguy's boat, which then have to be filled and faired), and little or no fairing. All the panel edges and bulkheads are the right shape, with sealed edges and cutouts for doors and hatches, plus the perfectly fitting doors and hatches. All shelf and bulkhead landings are precisely located so they only have to be glued in place, then the hull halves glued together in self aligning joins. The interior of a conventionally built boat takes 50% of the time, most of it doing fiddly, frustrating alignment of pieces in 3 dimensions. It is far less time and no fiddly bits with Intelligent Infusion.

People have been hand laminating boats for decades. It works and the boats don't fall apart. They have also been joining components together suddessfully. But the resulting jon is heavier than it needs to be, costs more, takes longer and is frustrating. Multiplied if you are doing it in small pieces with heavy joins. Multis work best and cost less when they are light.

Maybe build a small piece of your boat, then do a small infusion and consider which is the best way to proceed. Test procedures, and samples are part of the Intelligent Infusion plans.

There are a couple of Intelligent infusion build blogs at Building Blogs – Harryproa http://harryproa.com/?cat=2 The system is being improved all the time, so these are all out of date, but should give you some ideas of what is involved.

 

Here is a short video on how to do infusion.
{{model.productMeta.WebStoreDisplayName}} http://www.easycomposites.co.uk/#!/composites-tutorials/how-to-do-perfect-carbon-fibre-resin-infusion

 

Thanks... a lot of good data... Can one rent or build infusion equipment on the cheap? I am already going to have to deal with a cnc for cutting the parts... I guess that I could learn to infuse a core foam on table or in the mold... a lot more reading for me. Thanks again.

 

Thanks Jim,

This does appear to be the less mess, clean and easy solution, however, I would just have to think about how I would incorporate this technology within my project. Do I create the parts on a table and then place them in the mold/jig or do I infuse the parts in the mold? Maybe the design should be altered to make use of this process.

I have a lot of thinking/reading to do.

How would one use the infusion method on a multi-chine boat designed for plywood, like a Richard Woods design? Any opinions out there?
My hull is basically a stitch and glue ply panel type design for simplicity and speed (cnc build), but I do not want to use wood in my project, just composite or composite/foam core.

Thanks to all for the insights,

 

Infusing a whole hull or a half hull in a mould is not for amateurs by all I have been told. The risk of total failure is high. If you want to build in foam and wet bag or better; infuse and with small panels; the only real way to do so is to ask the designer if it’d work and if he has plans to reflect or if you’d need to do all the lofting (big trouble in a small space). You would probably struggle with a fully rounded hull, so hull shape is important. Rob would give you better advice, but if you are willing to vac bag or infuse; then there will certainly be designers out there with plans to fit. The flica being built in Vermont I mentioned is most likely possible done in foam. It actually is a combination of foam and ply now. If you are willing to infuse or the worse option wet bag; stay away from rounds or curved hulls for space saving mainly; you ought to find a designer willing to help. If you post a question as to which of Richard’s boats can be built in small panels; he would be the better one to ask on his forum or via email. If a boat can be built in ply panels; foam is also certain, but the glassing is different, or the thickness different or both; along with the designer’s willingness to redo in foam...

Getting away from hand laminating is required for foam. The consumable costs are higher for infusion n wet bag, but the end results far superior. You can now ask designers if they have plans to suit the workspace. At some point; you will need to move to a larger space to finish, or given the space; add to the back of your garage or find out if you can tent the front of it. Many cities do not allow such.

And plan for epoxy. The smells of poly near your living space are horrid. Vinyl? Don’t know... The space should be climate contolled a bit. Epoxy kix fast in hot and won’t kick too cool. Humidity is also a problem for wet bagging.

Good luck.

 

Thanks... I will experiment and then build the tender (dingy) first... I still think that the segmented construction is the way that I need to go.
I will put the strong-back on heavy casters and roll the whole jig out into the driveway and then pull the part using a gantry crane on rubber tires. I plan on bring the parts out to the back yard for assembly and I will tent each half of the boat so that I can put air-con and keep the project out of the rain during finishing.

I still think that I want to build a temp female mold for each part... and then glass. I would like to opportunity to see the part negative to ensure that I am not missing anything prior to doing the lay-up.

It looks like a good vacuum pump is the only real special equipment that will be required for bagging or infusing. So this does look do-able.

Thanks, again for then help...

 

Strong backs for larger boats are anchored to the floor; not rolled about.