kawi254 wrote:Not a construction Engineer but i did my research with the roadside guys along outering road, Kariobangi and KAPA Mombasa road last year.
The concrete mold you can have it made for you at 8K-11K per mold by the Juakali guys. Metallic mold is advised as the wooden one takes in moisture and wouldn't last i.e if you intend to be making the concrete posts for years to come. 3 Y8 bars per post is what they use to reduce costs, but i have seen posts with 4 bars which i guess results in more strength of the posts.
Depending on strength required/finances you can use 1:3:6 or 1:2:4 ratio for cement:sand:ballast.
Ballast size is your normal ballast used for construction, i believe 3/4 inch. To give the posts a smooth finish they will mix the concrete mixture with the very fine ballast (they call it dust). Was strongly advised to use ballast crushed by machine and not those ones done manually because you need an even size ballast (3/4 inch).
So that the concrete doesn't stick to the molds you will need oil to apply before pouring the concrete mixture into the molds.
One mold can do 3 posts per day if you push it i.e one very early in the morning, another at around 1p.m and last one late evening. Be careful on the curing time because if not done well they will get cracks soon after.
1 bag of cement will give you 3 posts. 1 post at the roadside will go for around 1,800/= (last year price). If you need to transport these posts your cost goes up so depending on your quantities your may decide to make on site or buy.
I know I'm light years behind, but might you still have the contacts for these guys? I'm looking for someone who has the skill set in making the concrete poles.