A rock & roll machine

Rotomoulding machines come in two basic configurations: biaxial and rock & roll. Each configuration has its own benefits and draw-backs. I have designed and built both types in the past, so now that I need a new machine for my company, I had to think carefully which type of machine I want to build this time.

For most rotomoulding companies, quick moulding cycles and fast turnaround time between cycles is of the highest priority, making biaxial machines the first choice for the vast majority of applications. To be frank, for most rotomoulded products that approach works perfectly fine. On the contrary, I specialise in the rotomoulding of complex products that routinely require multi-segment moulds, a variety of moulded inserts, moulded-in graphics and also negative draft angles, while at the same time having critical specs regarding wall thicknesses that may vary between different parts of the product.

Having substantial experience with both types of machines, I feel that I can control the process better with a rock & roll machine. I’m happy to compromise on the speed of the moulding cycles if I can get a better quality product, consistently. I am not interested in making products that become consumables. I prefer to make products that last.

Below are screenshots of the CAD design for my new machine. The completed machine will naturally have more things added than what the CAD design shows, such as the cladding and insulation on the oven shell, the rotating components, electrical wiring, gas and pneumatic pipes, control panel, etc. But when I design a machine that I build for in-house use, I rarely add these final details in the CAD phase. I’m pretty hands-on with the building of my machines, so those details are perfectly stored in my head until my crew gets to that point in the building process.

I’ll post some pics of the completed machine in a few weeks’ time.

Rock & roll 2

Rock & roll 1


Pungwe River

The Pungwe River is in the Eastern Highlands of Zimbabwe. For part of its course, it runs through the Nyanga Nature Reserve, where permits are required. Below the reserve there are other sections that can also be paddled.

The river is a typical creek, with mostly class 3 to 4 rapids. Some sections might contain even more difficult rapids and unrunnable drops. Scouting of certain rapids is essential. Bear in mind that the pools are likely to contain crocodiles.

The area is beautiful, making it worthwhile to go there for a longer time to explore the surroundings. Read More

Zambezi River

The “Mighty Zambezi” has become one of the most incomparable rivers in the world. It is big, wild and intimidating, but relatively easy and safe, making it a mecca for commercial river rafters from all over the globe, and a playboater’s heaven.

At a length of 3540km it is the fourth longest river on the continent. It rises in northwestern Zambia, from where it makes a bend through Angola, and then travel south through Zambia, before heading east to the Indian Ocean. On its course it forms the border of northeastern Botswana and the boundary between Zambia and Zimbabwe, where it flows through Lake Kariba. Further down it crosses central Mozambique, where it flows through the lake of Cabora Bassa Dam, and then into the Mozambique Channel, before meeting the ocean. Along its course, various sections of whitewater can be found, but the most famous rapids can be found in the Batoka Gorge.

Victoria Falls, alias “Mosi-o-Tunya” or “Smoke that Thunders”, is one of the seven natural wonders of the world. It is also a World Heritage site. The Falls mark the start of the Batoka Gorge, where the Zambezi provides the best one-day whitewater rafting trips in the world.

Apart from the rafting, other commercial activities are also offered, providing a full-on adventure holiday. Anything from bungi-jumping to body-boarding to hot-air ballooning is on offer for thrill-seekers.

Several luxurious hotels and bush camps in the area cater for all levels of affluency. More rustic activities can also be undertaken, such as game drives and flat-water cruises above the Falls. The river is wide and flat above the Falls, offering close-range viewing of Africa’s plenitude of wild animals.

The myth of the Nyaminyami, the river god, has been exploited on a large scale by entrepreneurs, who have amplified its status far beyond that which the BaTonga people could have imagined.

The small town of Victoria Falls used to be the hub of activity for travellers, but since the political turmoil in Zimbabwe, it has lost some of its business to Zambia on the other side of the river. The little town of Livingstone on the Zambian side, named after explorer David Livingstone who discovered and named the Victoria Falls, is used as a base by many kayakers who want to play the Zambezi. Read More

Kunene River

The Kunene is a major river with some serious gorges in totally inhospitable terrain, cutting through the Kaokoveld and Namib Desert.

The river has been paddled from source to sea, first by Willem van Riet and Gordon Rowe, and then by Darron Raw, Johan Radcliffe and Matt Pitman. Other parties have also done shorter sections of it. All those who lived to tell the tale (and not everybody did) have stories of extreme sections interspersed by pools inhabited by crocodiles. Some major portages are also part of the mission at certain sections.

The upper part of the river, going through Angola, is relatively uneventful, with crocodiles being the greatest cause for concern. There are a few waterfalls that should be portaged, and the terrain is rugged and isolated. Unfortunately for the environmental cause, but fortunately for paddlers, there are no more hippos on the river, as they were all shot during the ongoing war in Angola. This applies to wild animals in general in this region.

From the well known Ruacana Falls, the river forms the border between Namibia and Angola. A hydro-electric scheme at Ruacana regulates the flow of the river from here on. The 120km section between Ruacana and Epupa Falls is as accessible as you can get in this rugged area, with a road following the course of the river. Commercial operators offer ad hoc rafting trips on this section. The rapids are mostly class 3 to 4, but don’t under-estimate the section. A highlight is the Ondurusa Falls, about 40km downstream of Ruacana, which can be negotiated. Read More

Fish River

The Fish River Canyon is regarded as the second-largest canyon in the world, next to the Grand Canyon in the USA. The appearance of the canyon is very similar to the Grand Canyon: deep, barren, rugged.

Unfortunately the river runs through a desert, and seldom has moving water in it. During the winter months, when the river is reduced to a series of standing pools and the temperature is bearable, the canyon is a popular hiking trail.

Every summer the desert receives its share of rain, and the dry riverbed is transformed into a lively stretch of water with some interesting rapids. The river normally retains a paddling level for close on two weeks, during which competent paddlers can enjoy an otherworldly experience. Read More

Mutale River

The Mutale is one of those unknown jewels. It offers spectacular scenery in a deep gorge and challenging rapids.Ideal for: Kayak

  • Grade: 3 to 4-
  • Length: 25km
  • Duration: Long 1 day, easy 2 day
  • Type: Pool-drop
  • Put-in: Take dirt road down to river, walk down last bit where road ends
  • Take-out: Road close to river on the right, just after gorge opens up
  • Dam controlled: Fundudzi Dam
  • Permits: None

Read More

Letaba River

The Letaba is one of those rivers that are still waiting to be explored. It is one of the major rivers in the Northern Province and its upper stretches are in the Magoebaskloof mountains, which receive a fair amount of rain every year. 

The section described here is just below Ebenezer Dam.  During the summer a paddleable level can be expected most of the time. As far as I know, none of the other potential sections of this river have been paddled yet.

  • Ideal for: Kayak
  • Grade: 3 to 4
  • Length: 7km
  • Duration: 3 to 5 hours
  • Type: Steep and narrow
  • Put-in: Bridge where R528 crosses river
  • Take-out: Low level bridge on dirt road that turns off from R528
  • Dam controlled: Ebenezer Dam
  • Permits: None

Read More

Blyde River Canyon

The Blyde River Canyon has become one of the most popular stretches to paddle for both kayakers and commercial rafters. The canyon – the third largest in the world – is one of the natural wonders of the country, and a trip down this river offers a different view on the awesome scenery. The clear water is also something to appreciate if you are used to the sediment-enriched water found in most rivers on the sub-continent.

  • Ideal for: Kayak, croc
  • Grade: 2 to 4
  • Length: 9km
  • Duration: 3 hours to full day
  • Type: Pool-drop, some long rapids. Canyon.
  • Put-in: Mariepskop campsite
  • Take-out: Blydepoort Dam
  • Dam controlled: No
  • Permits: Yes, arranged via commercial operators
  • Commercial operators: Blyde Adventure Centre, Induna Adventures

Read More

Sabie River – Lower section

The lower Sabie is a popular commercially rafted stretch. It is easily accessible and offers exciting rapids to clients without scaring them. It’s also a challenging run for K1-paddlers (for whom the section might be a bit short to make it worthwhile) and a nice playsection for kayakers. The river runs quite close to the road and is skirted by farmland and holiday accommodation, but the thick vegetation gives the impression of isolation.

  • Ideal for: Kayak, croc, K1
  • Grade: 1 to 3
  • Length: 8km
  • Duration: 3 to 5 hours
  • Type: Flat sections with small rapids between
  • Put-in: Short dirt road next to the Sabaan River down to the confluence with the Sabie
  • Take-out: On private farm
  • Dam controlled: No
  • Permits: Permission from Induna Adventures at put-in. Their office is just on the other side of the tar road. Permission from farmer at take-out. Arrange via commercial operators.
  • Commercial operators: Induna Adventures

Read More

Sabie River – U1 section

The U1 section of the Sabie River is the original Upper Sabie section, and has been renamed after more sections were opened up further upstream. It has become the testing ground for many kayakers to measure their technical river running skills. Some of the rapids are somewhat nasty. That said, it must also be mentioned that all the major rapids are easy to scout and portage.

  • Ideal for: Kayak
  • Grade: 3 to 4+
  • Length: 7km
  • Duration: 3 to 5 hours
  • Type: Pool-drop, steep rapids.
  • Put-in: Turn off 4 or 5 km after crossing the Sabaan River, follow dirt road down to river (4×4 needed)
  • Take-out: Short dirt road next to the Sabaan River, down to the confluence with the Sabie
  • Dam controlled: No
  • Permits: It might be necessary to ask permission at the put-in, as a new lodge has been built next to the road going down to the river. Permission from Induna Adventures at take-out. Their office is just on the other side of the tarred road at the take-out.

Read More