Infusion Plan

if your bag was holding a vacuum for two hours with very little drop off that is prefect enough for me

What I found was that the bag can hold vacuum and may seem fine but it relaxes as the resin flows and that is when pinhole leaks reveal themselves, usually in the pleats of the bag and most of the time it's pretty easy to locate them and quickly plug them.

I didn't have a problem with the MTI itself, the problem was that I was being sloppy and was relying on the MTI to cover my errors. Once I started being more careful I realized I did not need the MTI but as you say, if a pin hole leak does develop, it's nice to know resin will not escape the bag )

But I am a strong proponent of infusing inward, look at how simple the line layout is in the attached image, only two lines cross your hull as opposed to … what … about 40 lines in fish bone system??

Plus the converging resin front flows very even, I have done as far as 5' with no signs of slowing down. I think if you try this style once, you will never go back to the other systems )) I would test on a panel first to see how it works with your flow media etc…

 

Unfortunately I have understand that the technique of infusion is very delicate and every piece has a your problem and her management.
The perfect infusion is a result only of a big experience!!!
I did a lot of a tests and every test has given me different results!
When I started, I could not to get a perfect vacuum because I used tacky tape black.
After, I understand its and I change tape, now I use only yellow and the vacuum is about perfect!
But I saw that in a infusion must be few connectors, less possible because the air can enter also to here!
Then I used a taps for adjust the resin flow but after end of infusion I saw that sometimes air entering of taps (CLOSE) so, I learned to use taps only during infusion, after the infusion, I crush the tube so I sure that air can't enter!!
Sometimes I had a problem with a new bag that it had a pinhole and I can't feel with leak detector but I saw only when the resin walked into the laminated...

Jorge, how many time need for infuse all this boat with fish bone system?
I think about 30/40 minutes to 25°C about (now pratically)
What do you think?

 

Yes, I agree, every system has it's ups and downs. Go with what you feel comfortable but one day you should test infusing inward.

My infusions of 4x8 panel, both sides at same time are exactly the same as doing one side at a time. Same as the last infusion I did, the entire hull, took about the same amount of time as a single panel 35-40 min because I had more resin feed line.

Have you tried the cut and perf'd core? I want to give that a try next time.

Actually next test is to assemble a boat hull entirely … using stringers and bulkhead frames cnc cut from foam core. Assemble the pieces using fiberglass screws using system like ikea but running a layer of glass between the frames so that the skin is uninterupted, then bagging the entrie boat, and shooting in one shot both sides. I envision the boat will be suspended on a rotating stand, like what you grill chicken on )) so I can view infusion on both sides at same time. Bag would be welded to fit boat perfectly. In this manner you don't need molds and you can have as many boats as you want, simply cut the components, frame them up and lay your glass then infuse. Im still working out the frame system, it would make for a very strong boat this way and fast to construct.

 

Can you believe I am still not done!!! Making some headway on the console .. my feet will be 30" above the deck






This is the interesting part, decided to build the platform my self. Got some 1" thick perf'd core and I am going to do a little experiment.

Without interupting the laminate, I am going to infuse this in one shot. The fillets will all be built into the core and everything pinned together with pocket screws. If this works, then this would be the much better way to build a one off without a mold! lol … I will post the infusion strategy once I get it all together.

 

Well today I played with the new system I mentioned.

I used an Omer 81P stapler with Fiberglass Staples by Raptor to attach fillets to the edges of the foam. The staples penetrate the foam easily, I was at low power 60psi, perfect, but the staples won't hold that well so you have to be gentle or add a coupld of dots of glue … which I did even though it's to tack the pieces together till you infuse, the glue was easy, I used Titebone III. The fillets are small cut from 1/4 inch core cell, I had the stuff so decided to use it, I don't think I will have any problem with the tight radius.

I also added pocket holes to later join the components. In the images I butted the foam just to show what I am doing when I am ready to put it all together, the different pieces will attach over the laminate via the pocket screws … very easy assembly. I wrapped one of the sides of the platform using staples as well but ran out of time, I will post pics of the assembled platform next week.

As far as time to build the pieces, really fast so far.

Here are some images, more to come with a better explanation but I am getting excited! If this works, what a great way to build a boat!!!

pieces will be easily tacked together with pocket screws once the laminate has been loaded.


fillets on vertical and horizontal joins


showing the staples


showing the pocket hole which will be join the pieces once the laminate is run

 

I don't get it Jorge.... Are you going to infuse the whole shebang in 1 continuous laminate? If so, what are the pocket screws going to be doing?

I think I told you this before, but I use a moisture cure polyurethane glue for gluing foam together. It sets pretty quick, and use staples to hold things together rather than clamps until this glue is cured enough to work with it - about an hour in the tropics. Once cured, I pull out the staples before going ahead with the laminate... This glue line is stronger than the foam itself and is completely uneffected by moisture ingress should it occur at some later date.

 

Hey groper,

Yes it will be infused in one shot.

What I mean by no interruption of the skin is that, any where panels abut, there will be layers of glass between them. That is why I had to attach the fillets to panel edges.

So in the images, the side panels, cross supports and base are just sitting there. The pocket screws won't go in until the glass has been laid between them, true monolithic

Using these same type joins, I could form an entire "small" boat. My build would have been perfect for this system. It would require a bag around whole boat though.

The staples I am using are the Raptor Fiberglass ones, you can leave them in. I also used them in a few points to keep the glass in place. Im guessing you could put a couple in to hold flow media in place as they are supposed to shear off pretty easily when removing bag … maybe I won't try that though!! or maybe just one for the sake of the test!!

The next pics will make it clear what I am doing, I am even going to infuse a step on the platform using the same system as well.

 

Still don't get it...

Unless my understanding of engineering is precluding me from understanding your methods?

If the screws are to form a structural connection between panels, then this is not adequate. If the panels are to be glued together than that's fine, but then the screws are redundant. If the laminate is continuous across the fillets, then the panels are joined anyway, no glue or screws required? Thus I still don't get it

 

I can't glue the core because it would interupt the laminate … this is the idea


This way I can build the entire structure and shoot it all in one shot. No mold or jig needed.

I think it might even be possible to run only a single skin between cores and then add the subsequent layers after as those don't aid in shear anyway. edit .. I don't know that for sure, just guessing, and you would still infuse in one shot

 

I had to go out of town so haven't made much progress on the platform experiment. Got a few hours in on it today.

I am digging the staple gun, have to keep reminding myself to keep it to a minimum, you could easily bind the laminate and get wrinkles if you got carried away. I should be finished wrapping this on Monday. EDIT: One important discovery so far … stupid to use the pocket hole screws, in the future I will use fiberglass nails to pin this together and wrap the panels first before assembling.





You can see the infusion flow under the base, I plan to flow the resin in from the edges of the part. There will also be infusion flow media on the exterior side panels.

I have two vacuum outlets on the base and one hose running the length of the top of each side panel.

I will also have a vac hose on top of each cross panel. I will open vac and resin lines to cross panels as soon as base infuses. Each cross panel will have flow media on one side and a resin feed at it's base.

Core is perf'd, resin flow is only on one side.

I also picked up this for $100, wanted to see if I could use it to make quick welds in the bag. Works beautifully in the shrink wrap type of bags but doesn't get hot enough to melt the nylon bags. There is no doubt in my mind as to the integrity of the weld but I did not put a vacuum on it, you can't tear it apart without destroying the plastic.

Going to check around and see if they make these with hotter elements. would be great to make a bunch of 6" pleats or actually form a bag to a specific shape. The air heat guns with knife tips definitely get hotter but the run a few hundred and up. That is what I would use if I was welding a complete bag that had to fit around bulkheads and stringers etc...

 

Hi Gorge, for these flat structures is it worth the effort of working with a complicated structure? Isn't it quicker to make a big flat panel then cut it up and bond it together? Even if you infuse all the taping it would be easier/quicker? My experience with this sort of thing is that the bag tension distorts the panels and building the bag although possible is time consuming. Its a great exercise though. I think what Groper is on about is that you don't need laminate under the foam connections. So you can just bond the core together with a quick set adhesive. I like 5min epoxy.( just in spots as required as when infused all the voids will get filled anyway) If you want resin to flow under the connection then don't bond 100% only glue stitch it together. Peter

 

Hey Peter, yes of course there is no benefit to making this platform like this, I agree, however ...

imagine that this was an entire hull … I would be shaping the hull with components which remain after the infusion. So stringers and bulkheads and all kinds of little reinforcements would form the shape of the hull, no tool or mold needed.

yes the bag would have to be carefully crafted to fit the interior and you would need to figure out how to suspend the structure and even rotate it for easiest work flow but say it took you a week or even two to ready a boat for infusion in one shot would be pretty sweet.

Then you could just store the cnc cut files and when somebody orders a boat, wham bam thank you mam! No need for a huge space to store all your molds no expense in building molds and freedom to change as you wish

 

Yes Jorge I can feel the dream but I think the answer lies in premade panels and adhesive rather than foam, complicated construction and complicated bags. I was involved in developing the production plan for a 45ft Riviera boat here some 12 years ago. We decided to put in the main stringers into the infusion plan. They were 600mm high by 75mm wide and fitted to the hull bottom. Two longitudinals. We timed the entire process doing it in the mould and out of the mould and out of the mould won by a long shot. Taking it to the next level ie doing more stuff in the mould would not have made sense but that was the concept, like you they wanted to do as much in the bag as possible. If you made flat panels, cut to shape and used a good tough adhesive with good fillets I think you would find the structure to work out quite nicely at Boat/component level. But keep dreaming, we only get ahead by following dreams & we only find the limits by going past them and failing! Peter

 

There's no way you would end up with a fair hull Jorge. Large panels will warp and sag, I just don't think it's worth it in terms of time spent at the end of game.

Small jobs like your doing now, I found were at least twice as slow as simply making huge flat panels and cutting them up like ply wood and bonding together - same as peter eng replied.

 

Ok, that's two nays LOL

For the sake of my stubborness and my dislike of cutting fiberglass panels, I will have to try it out but just a little row boat or something ))