I am in the market for some cheap "cold galvansing paint". Zinga is one such product but there is also Galvafroid, Tractol 927, ZG90 and Rustoleum 1085 too...All seem to cost a small fortune!
You see I'm building a custom made boat trailer for my Hemming and Morris Marina 16 GT boat. I've been unemployed for over a year now so I'm on an extremely low budget.
To keep costs down I've had to go for plain mild steel.
80x40x3 RHS for the main longitudal side beams (2 x 5.5m long), the two transverse "swing beams" are 60x40x3 RHS and the wobble roller carrier beams on the swing beams are 50x30x3 RHS...So I am not only worried about external corrosion but about the above box sections rusting from the inside out!
I've investigated the possibilty of having the steel hot-dip galvanised (HDG) but Joseph Ash (my closest HDG specialist) have a £85 minium order charge.
That has effectively ruled out HDG on cost grounds (did i mention I'm on a very tight budget?) which is why I have started looking into cold galvanising paint options.
I noticed that most of these paints require the application of shot blasting to prepare the de-greased steel surface properly so that the paint is guarenteed to adhere to it well.
I have no experience of shot blasting but I guess I will have no choice but to do it myself as well I cant afford to have that done for me.
I have been looking at a gun like the Sealy SG10 or one of the newer tech "recirculating" (or is it "recycling"?) shot blasting guns.
According to the blurb, unlike the SG10 the latter allows you to capture and reuse most if not all of your grit and as the grit doen't just go everywhere like it does with a SG10 type gun (because its trapped by the rubber shroud over the nozzle). You probably dont need to wear such bulky and expensive protection gear either?
I am seriously considering buying one...They cost from around £20, inc VAT then I have to factor in the cost of the grit.
Someplace up North is selling 25kg bags of grit for just £5 each...But because of the weight the postage is very expensive actually making it more economical to get grit locally, even though its costs more.
I know that the nozzles do erode over time so hopefully I will be getting one that has replacement nozzles available. I am still researching which is the best one to get.
As for the inside of the RHS's...Having an inventive mind I thought of a way to blast the inside of the box section too.
A long flexible airtube that can passed along the entire inside the length of the RHS, which has a 360 degree conical nozzle on the end that sends the shotblast out at 90 degrees to the axis of the hose...You would power up your compressor, add the grit suction apparatus to your grit bag and then you would pull the pipe/nozzle combo slowly backwards by hand as the nozzle evenly blasts the entire inside of box section. Then you fit a bag tightly over one end of your box section and blow air down the box section from the other end. This will blown out any abbrasive grit left inside and it will be captured by the bag at the end for reusal. At least, thats the theory.
I am sure that a similar long flexible tube arrangement/method could be used for spraying the inside of the box section with an effective de-greaser and for rinsing it out again, prior to blasting or even for allowing the entire inside of the box section to be sprayed with cold galvanising spray after blasting...Its all possible but it would take time to perfect and time isn't on my side as I can't use my boat until the trailer is made and we are rapidly running out of summer.
So I am now looking at spraying traditional Waxoil down the inside of the box section instead...Any thoughts?
You see I'm building a custom made boat trailer for my Hemming and Morris Marina 16 GT boat. I've been unemployed for over a year now so I'm on an extremely low budget.
To keep costs down I've had to go for plain mild steel.
80x40x3 RHS for the main longitudal side beams (2 x 5.5m long), the two transverse "swing beams" are 60x40x3 RHS and the wobble roller carrier beams on the swing beams are 50x30x3 RHS...So I am not only worried about external corrosion but about the above box sections rusting from the inside out!
I've investigated the possibilty of having the steel hot-dip galvanised (HDG) but Joseph Ash (my closest HDG specialist) have a £85 minium order charge.
That has effectively ruled out HDG on cost grounds (did i mention I'm on a very tight budget?) which is why I have started looking into cold galvanising paint options.
I noticed that most of these paints require the application of shot blasting to prepare the de-greased steel surface properly so that the paint is guarenteed to adhere to it well.
I have no experience of shot blasting but I guess I will have no choice but to do it myself as well I cant afford to have that done for me.
I have been looking at a gun like the Sealy SG10 or one of the newer tech "recirculating" (or is it "recycling"?) shot blasting guns.
According to the blurb, unlike the SG10 the latter allows you to capture and reuse most if not all of your grit and as the grit doen't just go everywhere like it does with a SG10 type gun (because its trapped by the rubber shroud over the nozzle). You probably dont need to wear such bulky and expensive protection gear either?
I am seriously considering buying one...They cost from around £20, inc VAT then I have to factor in the cost of the grit.
Someplace up North is selling 25kg bags of grit for just £5 each...But because of the weight the postage is very expensive actually making it more economical to get grit locally, even though its costs more.
I know that the nozzles do erode over time so hopefully I will be getting one that has replacement nozzles available. I am still researching which is the best one to get.
As for the inside of the RHS's...Having an inventive mind I thought of a way to blast the inside of the box section too.
A long flexible airtube that can passed along the entire inside the length of the RHS, which has a 360 degree conical nozzle on the end that sends the shotblast out at 90 degrees to the axis of the hose...You would power up your compressor, add the grit suction apparatus to your grit bag and then you would pull the pipe/nozzle combo slowly backwards by hand as the nozzle evenly blasts the entire inside of box section. Then you fit a bag tightly over one end of your box section and blow air down the box section from the other end. This will blown out any abbrasive grit left inside and it will be captured by the bag at the end for reusal. At least, thats the theory.
I am sure that a similar long flexible tube arrangement/method could be used for spraying the inside of the box section with an effective de-greaser and for rinsing it out again, prior to blasting or even for allowing the entire inside of the box section to be sprayed with cold galvanising spray after blasting...Its all possible but it would take time to perfect and time isn't on my side as I can't use my boat until the trailer is made and we are rapidly running out of summer.
So I am now looking at spraying traditional Waxoil down the inside of the box section instead...Any thoughts?