Start Roto #4 | Can you use recycled plastic in Rotomolding? — LIVE

What you gain by watching

• Discover how to identify low-quality recycled materials before they cause silent losses and compromise the durability of your parts.
• Learn in practice the difference between post-industrial and post-consumer, and master the simple tests that prevent contamination, punctured parts, and unexpected production stoppages.
• Understand how to map your process, run a corrective tryout, and use recycled material in the right place to increase productivity by more than 120% without handing your customer to the competitor.

Episode chapters

1. 1

   Cheap recycled material may be silently destroying your production

   In the fourth Start Roto, the conversation begins with a warning that many discover too late: that recycled material bought for a few cents less may not have the necessary quality, causing silent losses on the factory floor and compromising the part you put on the market. We talk about how to identify these traps before falling into the famous 'dirty economy,' showing that choosing raw material is the first step to planning costs and ensuring the final quality of the product. At this stage of Start Roto, focused on ideation and planning, we reinforce that knowing the origin and characteristics of the recycled material is not a detail, but a competitive differentiator.

   ▶ Watch at approximately 3:11
2. 2

   From dream to market: how to structure a rotomolding business from scratch

   Many entrepreneurs have a brilliant idea but stumble on the question: where to start, with what capital, with what structure? In this episode of Start Roto, we present the complete path — from validating the product with partners and prototypes to setting up manufacturing and the sales strategy, including the migration to digital. And, at the end, we answer the question everyone asks: after all, can recycled plastic be used in rotomolding? The answer, as always, begins by understanding the difference between plastic and resin.

   We put you at the penalty mark with the client, with a whole effort. So it is important that you really know that the first step, we are here to give all the necessary support.

   ▶ Watch at approximately 8:21
3. 3

   How to escape the trap of selling your recycled material too cheaply

   We start the episode with a concern that looms over the factory: how not to fall into the trap of selling recycled material at any price, without knowing exactly how much to use and in which situations. Then, we talk about the points of attention you need to observe, showing real market values — such as 0.50 and 1.30 — and we suggest tests you can run at your company to validate the application of the material. Meanwhile, we solve a live sound technical problem and, in the middle of the chat, we receive illustrious visitors in the studio, and we promise that you will get to know them better as the conversation goes on.

   ▶ Watch at approximately 14:17
4. 4

   The cheapest resin isn't always the one that gives you the most profit at the end of the day

   In this part, we get real about the famous 'savings per kilo': that resin that looks cheaper can hide a huge loss in production waste, with defective parts, bubbles, and delays. We shared real cases where paying a little more for quality material guaranteed almost zero waste at the end of the day, and we showed the crucial difference between post-industrial and post-consumer — while one is clean and goes straight back into the process, the other can come full of hidden contamination. We also talked about the danger of polishing the aluminum mold, which can clog the porosity and fool everyone until the first part comes out and reveals the problem.

   I've already had cases where you pay fifty cents more for a product, but your waste at the end of the day was almost zero.

   ▶ Watch at approximately 19:18
5. 5

   Post-consumer or post-industrial: the difference that changes your cost center

   On the factory floor, the question that comes up is: after all, what can go straight to the grinder and what requires a more delicate process? We talked about the crucial difference between post-industrial, that clean material that comes out of production, and post-consumer, like dairy boxes and PET bottles that come back contaminated, showing that each type requires a specific path of washing and separation so as not to compromise the new part. And we told the real case of a client with thirty tons of plastic sitting in the yard, which turned into an opportunity: with partnership work and identification by sector, that waste became raw material and money for the cost center again.

   ▶ Watch at approximately 24:28
6. 6

   Why changing batches without testing is a mistake that can stop your production

   We found out that the rush to replace material can turn into a nightmare: if you don't test the new batch beforehand, the client becomes your testing ground, and then come stuck parts, stopped machines, and losses. We told how immediately switching material, without knowing the supplier or the batch traceability, is a trap — and we showed the safe path: get a small sample, test it, and only then buy in quantity. We reinforced that, even from the same partner, batches can vary if there is no control, and that it's essential to know the origin of the recycled material, because wrong mixtures or contamination create problems that could be avoided with a simple test.

   If you don't do a test with that material, if you don't have a laboratory, then the client is going to be your testing ground there.

   ▶ Watch at approximately 29:31
7. 7

   The portable toilet that hid a PVC pipe and destroyed the recycled batch

   We tell the real case of a supplier who ground up entire portable toilets without separating the parts, and only discovered the problem when the material broke at the extruder outlet: they forgot a PVC pipe in the middle, contaminating everything and leading the customer to face failures in the final product. We went further and showed how the lack of traceability almost went unnoticed also through the difference between rotomolding and vacuum forming on the sides of the toilet — a hard lesson about the invisible care that separates efficient recycling from silent loss.

   They ignored it, forgot about the pipe. Yeah, no, the guys just took that bottom part there, threw it in the grinder, ground it together with PVC, in short, ended up losing all that material.

   ▶ Watch at approximately 34:46
8. 8

   Hidden contamination: when a little box of nuts stopped the customer's production

   A simple little box with nuts and washers stored next to the machine went unnoticed until the customer sent the photo: the grinder blades, broken, with screws in the middle of the material. It was the warning that led us to map the five filters of the process to ensure that the recovered residue doesn't become a headache — we show in practice, with a blue part in hand, how a processor learns to identify the difference between virgin and recycled before ruining everything.

   I glanced at the part, I said: "man, but this here isn't virgin, no. This here is recycled material

   ▶ Watch at approximately 39:55
9. 9

   Black material isn't always the same: how to choose recycled without putting production at risk

   On the factory floor, the doubt about using recycled material comes up in practice: does every black one work? In this segment, we recall that color can be misleading and that the black part hides process defects — while the odor and shade variation reveal the quality. We talk about the care needed to apply recycled material in medium-risk parts and the warning for critical items, such as pallets and food-related products, where quality control cannot be flexible. We also show that separating scrap by color is the secret to reusing it consistently, and that modern pigmentation is an ally, as long as the cost is worth it.

   It's not because it's recycled that it doesn't have quality. I see a lot of black material out there that has excellent quality for various applications, no problem.

   ▶ Watch at approximately 44:59
10. 10

    Recycled material in rotomolding: the clear-cut divide between myth and quality control

    When it comes to recycled material, the first question that hangs in the air is: how do you guarantee that the material returns to the process without contaminating the part? In this segment, we show that the answer lies in pigmentation — the rule is clear, recycled material almost always already comes pigmented, and only in rare cases, such as scrap from dairy crates, do we find natural material that allows us to apply whatever color we want.

    Material with moisture will cause problems.

    ▶ Watch at approximately 50:03
11. 11

    Recycled material: when the long cycle reveals the problem

    Recycled material is not always the most economical option — and the oven cycle is the thermometer for finding that out. In the fourth filter of our conversation, we show how a degraded batch can go unnoticed in black parts, but give itself away through the strong smell when the mold is opened. And we talk about the classic case: when the standard cycle doesn't work and the temptation is to increase time and temperature. We tell how the practice of the tryout, coming from injection molding, reveals the truth: run the virgin material to find the ideal minimum time and then compare it with the recycled one — if the difference is large, maybe the recycled material isn't worth it.

    You really see what your process is giving you in return

    ▶ Watch at approximately 55:23
12. 12

    The money your factory loses by not mapping the process — and how one tryout turned into a 120% gain

    On the factory floor, every minute is worth gold — and that's exactly where we realized that the difference between using virgin or recycled material isn't settled just by the price per kilo. We tell how that extra time to demold a part, multiplied by twenty or thirty molds, needs to be put on paper with electricity, gas, and labor in the calculation. We show the real case of someone who increased production of certain parts by more than one hundred and twenty percent just by doing the tryout correctly, and we reinforce that knowing what happens in your process — with a spreadsheet and aligned PCP — is what separates those who balance the books from those who only think about selling more and leave invisible money on the table.

    Because sometimes the person only thinks about selling, selling. Wow, the numbers aren't adding up, we need to sell more, we need to sell more, but they don't stop to observe how much money you're leaving on the table because of a process that isn't well mapped.

    ▶ Watch at approximately 1:00:40
13. 13

    Quality in rotomolding: why monitoring material flow is a manager's decision

    On the factory floor, quality cannot be the responsibility of the leader or supervisor alone — the director needs to understand the process to decide on supplier changes and make changes without fear of long contracts. We talked about how material flow is a variable that reveals part formation problems, such as the orange peel effect, and that it can be monitored with simple ramp tests or observation of part details. And we showed that ideal quality depends on what the customer accepts and what the process offers — sometimes, the required standard is overkill for the final product, and the manager needs to know how to balance this equation without giving up the minimum acceptable.

    There's no point in glossing things over, no. It doesn't work like that here. The director expected results.

    ▶ Watch at approximately 1:05:47
14. 14

    Bad batch in hand: how to mitigate the loss without handing the customer to the competitor

    In this excerpt, we talk about the classic dilemma of those who depend on recycled raw material: buying a batch that arrives as a surprise — sometimes bad — and discovering the problem only when using it. We tell the real case of the dog houses with porous roofs, when we found technical solutions such as diluting the bad material with virgin material and using additives, in addition to reserving a margin of good material to avoid delaying deliveries. The conclusion is that, between losing a little on cost or risking the relationship with the customer, the smart choice is to mitigate the loss and keep your word — because that pays off down the line.

    The surprise was inevitable, right? … we had to pray it would be a good surprise.

    ▶ Watch at approximately 1:10:50
15. 15

    Recycled material in rotomolding: how to choose the right part and the ideal supplier without losing quality

    We talked about the decision between using virgin, recycled, or a blend material in rotomolding, highlighting that the right choice depends on cost, the market, and the final product. We showed that the quality and consistency of the supplier are crucial to avoid losses, and that a competitive differentiator can be as simple as offering a reverse logistics program or a partnership for material exchange. At the end, we present an essential checklist for anyone who wants to migrate to recycled material safely: start by testing on low-risk parts and get to know your supplier deeply.

    We always say, you have to offer something extra. Even if you're going to produce something someone already manufactures, but you have a differentiator. What is my differentiator?

    ▶ Watch at approximately 1:16:14
16. 16

    The mystery of the 5 thousand liters of milk: the warning about traceability in rotomolding

    When a difference of more than five thousand liters of milk appeared in a client's month-end closing, we discovered that the cause was not the tank, but the lack of standardization in the process and the lack of knowledge about resin shrinkage in rotomolding. We talked about the importance of recording every batch received, running regular tests, and documenting everything, because this traceability is your defense when it comes to talking with the supplier. And, in the end, we told how good accounting advice can be a strategic investment, helping you find the most advantageous tax classification for your business.

    That batch you sent me didn't turn out very well, man

    ▶ Watch at approximately 1:21:53
17. 17

    From the factory floor to the oven: what's coming up at Rotocast

    We closed the episode by talking about how those who come to us often don't even know where to start when investing in rotomolding — and we remembered that it's not just the search for specific products that we do with our partners: we have projects and ideas to guide those who want to enter the industry. Then, we revealed the community's next concrete steps, with an in-person course in Guarulhos that will put participants at the edge of the oven to identify defects in practice, and we already announced that two new Rotocasts are confirmed, one about process control and another about a new technology for pigments and mold release agents that we're keeping as a surprise — the schedule is just waiting for Brazil

    Two days away from the company are not two days of course. It's one day to get there, plus two days of course, one day to come back.

    ▶ Watch at approximately 1:27:19