Vacuum resin infusion of a mold for a nurflügel microlight aircraft

[@andreschavarria1450]

For those interested in making a plug, I suggest to visit our new series on "Making a large composite mold of complex shape". Part 1 kzbin.info/www/bejne/qHybeot7ipJrpqM is ready since some time and Part 2 will follow soon.

[@andreschavarria1450]

Part 2 on covering the plug should be in a couple of seconds online: kzbin.info/www/bejne/p3PLd6qted6YfqM

[@utuberlesmouches]

Bravo ! Magnifique projet. Une aile volante Horten bientôt dans le ciel ....

[@Linktw0]

superb project. Im subbed for more of this

[@andreschavarria1450]

Thanks! If you want to see more about it, check-out our other videos. You'll find some on making the shell produced in this mold. We are also currently making the mold for the cabin and canopy: kzbin.info/www/bejne/j5ypgqSOqJtgl8U You find more details on the project in our blog at Wordpress, which has many pictures and documents the progress on a regular basis: hortenmicrolight.wordpress.com/

[@h4z4rd42]

Award winning video of the Most Annoying Bckground Music on KZbin. Or pretty close.

[@trailus-co]

NOTE before pressing play press mute lol

[@locktite401]

Ignoramus!

[@Pfsif]

My lower back is killing me just watching you guy work just 18" off the ground?

[@guintube]

Nice video....but you didn't show part being taken out. Would love to see it.

[@andreschavarria1450]

Thanks. We didn't film how we separated the mold from the positive. Sorry. However, we have a new video showing how we use that mold: kzbin.info/www/bejne/paeoioelotdmjJY Actually the piece we show in the new video-a honeycomb sandwich-is ready and we are making the second half. We'll upload more videos soon...

[@JOEGGGJOE]

The coupling layer on geled gelcoat: what is that (resin mixed with something else/slurry?) & why do you do that?

[@andreschavarria1450]

It's thickened resin, either with cotton flakes or chopped glass strands. I prefere cotton now. The surface of the gelcoat is always somewhat uneven. This coat helps to avoid that air bubbles get trapped between gelcoat and reinforcement. It also extends the processing time, as it contains fresh resin but still binds chemically to the gelcoat.

[@mitropoulosilias]

i did that and i got devorced in the proccess...

[@mudeltabeta]

i love the music....can you give me the name please......

[@BernhardEhm]

Beethoven - 9. Sinfonie - Ode an die Freude

[@tritoncreations9173]

Darude- Sandstorm

[@Thatguythere-u7r]

there is much to be approved on

[@d3xterown]

What are you making?

[@andreschavarria1450]

The mold was for a center section of an all-wing airplane: hortenmicrolight.wordpress.com/

[@TheLazyGuyWay]

No needs of wax before gel coat ?

[@andreschavarria1450]

Sure, a release agent needs to be used before geolcoat is applied. We wanted to be sure that it releases well and we used five layers of carnauba based wax and one thin layer of PVA.

[@venusreena2532]

What composites are used on the bendable wing tips being built today?.. Am working on a design and i would like to progress to composites..very flexable..

[@commanderkeeno5552]

Getting payed by the hour when putting the tooling gel on then 😂

[@andreschavarria1450]

There are some tooling gelcoats that can be sprayed. The one we used for that large mold is too thick to be sprayed. Next time we'll use one that is sprayable ;-)

[@falrus]

Hello! Thanks for tutorials. Which core is better for airplane wing production? Nomex hexagon core or 3D|Core?

[@andreschavarria1450]

That depends on three aspects: weight, effort and costs. 3D|Core can be vacuum resin infused, which means that it needs less effort. You make the dray layup, infuse and get your final laminate in one shot.The material is much less expensive (roughly one sixth). However, it consumes quite some resin, which means that the weight is high compared to honeycombs. Nomex honeycombs are very light, as most of their volume is air. They weight about one third of the 3D|Core and do not consume much resin. However, they are much more expensive and elaborate to produce. Three sessions are needed: first face laminate, cementing honeycomb and second face laminate. Only the first laminate can be vacuum resin infused and the second needs to be cemented in a geled state (eek!). You need some experience to make good honeycomb sandwiches. There's a video on my channel, which gives a good impression of how much work it is: kzbin.info/www/bejne/a4qyhWSKitykitU If weight is critical, money and time do not play a role, I would suggest to go for Nomex honeycombs. If weight is less critical and budget is an issue, go for 3D|Cores.

[@andreschavarria1450]

I forgot to mention that you can also use AIREX foam. It can be either vacuum resin infused (video: kzbin.info/www/bejne/epK2hGiJna1jfKM) or vacuum bagged. The latter results in less weight. We made some ribs this way (see kzbin.info/www/bejne/mHnPq5Sla55oppI).

[@falrus]

Thank you for the explanation. I also heard of "Soric XF" core materials. It's like a hybrid of hexagonal core and infusion ready foam.

[@andreschavarria1450]

Yeah, but I've never used them because they consume much more resin than comparable sandwich materials (Soric XF: 2.4 kg/m², 3DCores: 0.35 kg/m²).

[@andreschavarria1450]

Yeah, but I've never used them because they consume much more resin than comparable sandwich materials (Soric XF: 2.4 kg per sqm, 3DCores: 0.35 kg per sqm).

[@YG-lb1sd]

Music ?????, but Good processus,

[@markdiephouse]

What song is that please ? Starts at 8:30 ?

[@andreschavarria1450]

It called Controlled Relaxation by Codex Machine: freemusicarchive.org/music/Codex_Machine/Man_vs_Monkey_EP/CodexMachine-ControlledRelaxation

[@j.danaclark89]

What is the cost for the materials for a mold that size? and what is the time investment?

[@andreschavarria1450]

Honetsly, I didn't count the money we spent. It is for sure only a fraction of what you have to pay for a CNC milled ureol/aluminum mold. I can tell you roughly how much material we used for one half (surface 4 m²): 60 m² of glas fabrics, 2 - 3 kg of tooling gelcoat, 12 sheets of 5mm 3DCore, 15 - 20 kg of epoxy resin, and not to forget, vacuum bagging stuff. Regarding time investment it depends completely on the pattern. Most time was invested in its production (high gloss surface). The time spent in making the mold is negligible. If you have a pattern, it takes a couple of days to build a jig. One long session for tooling gelcoat, coupling layer and two layers of glass fabrics (air tight tub). The dry layup is ready in a couple of days, including trimming the core. Finally, the vacuum resin infusion needs half a day. Depending on the application of the mold, you might have to heat treat the mold, which takes again one day of mostly waiting.

[@j.danaclark89]

I work at a motorhome manufacturer in Canada helping build molds for fiberglass and we make our molds much differently to how you made yours. We use hand layup or chopper gun layup. Our time investment is about the same though. And we spray our tooling gel as well, we find brushing can cause porosity that can cause issues in high production molds. We make at least 200 parts between cleaning the molds, depending on the quality of the mold surface and the gel used on the mold.

[@andreschavarria1450]

I've heard of spraying tooling gel and thought doing it when we made this mold. The metal-filled gel I use is probably too thick for my spray gun, though. Do you use epoxy or polyester resin? What I like of vacuum resin infusion is that you can make the layup in calm and contact to expoxy is reduced to a minimum. Also, the fiber volume ratios are higher, which means that the mold is lighter. We do this in our spare time and having the possibility to make everything distributed over a couple of days makes it much easier for us.

[@j.danaclark89]

Andrés Chavarría we use polyester resin and I'm assuming gel. it's the optiplus system from polynt composites. We used to use a vinylester system called "ferro" by what was at the time Ashlands composites if memory serves. The vinyl was actually a lot nicer to work with, more predictable, less pin holes and porosity, easier and better repairs when the guys in production wreck them. I'm kind of wondering if a resin infused mold would actually be cheaper overall as the time investment is very close along with materials but considerably less resin is likely to be used? What kind of production numbers do you expect out of that mold over its life span? Assuming the people using it respect it and don't abuse it of course.

[@andreschavarria1450]

Hard to tell if this method would be cheaper. You need a very good vacuum pump, a suitable resin, and slightly more consumables, such as the infusion mesh. Polyester molds are, as far as I know, the cheapest in production. However, a long lasting mold might in the long term be cheaper-depending on the number of pieces produced. I use epoxy because I cannot afford to have much shrinkage (polyester has up to 7%). When done correctly, vacuum resin infusion produces perfectly wetted laminates, i.e. no pinholes or whatsoever (glass fabrics become transparent; see video).

[@WOLFandANGEL]

how long do you let the E300RI cure?

[@andreschavarria1450]

That depends on the room temperature. 24 hours is minimum, where more is better. Give it a couple of days to prevent deformation (room temp over 20 °C). Full strength is not reached before heat treatment, as it is else brittle like most slow curing epoxy resins. Thus, I usually treat these for 15 hours at 60 °C (140 °F) with a heating rate of less than 10 °C per hour (50 °F/h). You can speed things up by curing for one day at room temperature and tempering then at 60 °C for 15 hours (plus five hours for the ramp).

[@WOLFandANGEL]

Do you heat it with heatlamps? or do you bring it somewhere?

[@andreschavarria1450]

I use a self built temper-box with infrared heating film and PU foam panel insulation. Temperature and heating-rate are controlled by a microcontroller.The larger the piece, the more challenging it is to heat treat. For small pieces a good insulated and air tight box with a couple of incandescent light bulbs is enough. Large pieces can be heated inside an air tight tent with any sort of heat source, as long as the warm air circulates (fan). I've heard of people using old elctric ovens... The heating-rate and final temperature can be adjusted by letting some fresh air into the box/tent. With good insulation the amount of heating power needed is less than expect.

[@francescoilgrande1]

no hair protection... how many ended up

[@andreschavarria1450]

I've seen none in the mold ;) Hair is much less a problem than insects and dust. It's not a cleanroom environment and using hair protection is not going to help much...

[@Иной-ю8д]

Здравствуйте, а что за смола такая? так долго не застывает?

[@andreschavarria1450]

Eto Smola HP-E300RI ot Firmi HP-Textiles. Ona bila spezialna rasrabotana dlja injektije i sastivaet 300 Minut pri komnatnoj temperture. Etovo vremini hvataet spokojno, schtobi infusionieravat bolschuju detal.

[@Иной-ю8д]

Спасибо, оперативно.

[@Иной-ю8д]

Скажите, а с эпоксидной смолой можно инфузию делать?

[@andreschavarria1450]

HP-300RI jevlaetsa epoksidnoj smoloj. Smola dolschna bit otschen schidkoj schtobo infusija horoscho polutschjalas. Ne ljubaja epoksidnaja smola goditsa po schidkosti. Dlja etovo prodajutsa spetsialnije smoli. Tschem bolsche detal, tem vaschneja schtobi smola bila schidkaja

[@Иной-ю8д]

+Andrés Chavarría !!!

[@marcostgran9353]

In that project you don´t need to use carbon fibre across

[@andreschavarria1450]

Yes, probably it wouldn't be necessary. Considering the high weight of the mold, deformation can be a problem. This includes not only bending, but also torsion. It's better to have some extra stiffness. Production molds use a truss for stabilization, which is lacking here. The parts produced in this mold are thick and stiff (6.5 mm honeycomb), and should be shaped by the mold as precises as possible. The final shape is best achieved using ribs: kzbin.info/www/bejne/Y4GwmnyLer95hpY However, torsion is still an issue...

[@waqarghulam3548]

Please get some larger brushes

[@charlesbishop7583]

What the hell was that supposed to be? Not even a view of the finished part. No explanation, just really bad background something.

[@MrSpitfireMustang]

Music sucks.

[@1pierreandremercier]

INSTEAD OF THIS STUPID MUSIC WHY DON'T YOU GIVE VERBAL EXPLANATION OF THIS PROCESS. WEIRD

[@andreschavarria1450]

Because I think the video and the textual remarks speak for themselves. I'm also always glad to answer technical questions. By the way, you can turn the volume down if you dislike the music or simply stop watching...

[@jaishetty8586]

I felt like I was in a church , not a workshop.

[@Erik-rp1hi]

I liked the music.

[@ronplucksstrings7112]

I didn't much care for the music either, and wound up watching muted...its a significant production effort to add a voiceover and some non-native English speakers do not have the confidence in their speaking voice (who likes their own voice anyway?) or time to do this (he would likely want to be working on other parts of the craft than be producing videos)...I'm thankful for him having posted the video at all...there's always something to be learned... Andres; I would have had more overlap of fiber edges at Step 5A ...this would assure better continuous force distribution without stress concentrations... The carbon fiber edge and diagonal strips added don't add any torsional rigidity (only in X-Y axes, and not much in that as they are not prestressed))...if this component needs torsional rigidity, it needs a reinforcement in the Z axis from corner to corner. I would have liked to see debagging and inspection of the level of infusion at the northwest/southwest corners...at 12:25:45 clock time (end of video), those corners were still dry! Remember...dry fibers are not structural...only fibers locked in resin have structure! Thanks for posting, and safe flying!