Hey Ken,

I`ve used 2 liters of blue paint and 10% thinner for the whole table. I don`t know if it`s too much or not, I`m not a pro painter. I had also some paint noses hanging from the table due to the fact that light conditions were not so good.
But in the end everything looks fine.

Greetings
Claus

Hi Ken,

I would not call myself a guru but i have looked at so many square meters of steel being painted that i got a good knowledge what it takes to get a good paint system.

Like you point out the advantage of using alkyd paint and applying it with a brush and a roller is that you don't need any special equipment or special skills. Spray painting takes some exercise en training, just like welding :)

Anybody (well you know what i mean) can get a feeling of how to use a brush and a roller.

Hi Claus, I am trying hard to refrain from adding more toys in my shop... :o

Hi all,
To those who knows a thing or two about powder coating, I need some advice sound, experienced please !
Looking at getting some powder coating done for the beast, I know a lot about finishing, preparing & protecting wood, but NADA about steel, worst…. about powder coats.
I read & understand how & with what it’s done, but not enough info to please my doubts & curiosity!

What type of powder should I request for structural steel ; Epoxy, polyester or hybrid of those two ??? ( see this )
Also, for prep the steel, one tells me sand blast is the only way to go, another tell me phosphate cleaning is well enough for steel ( structure or not) indoor usage ( Ie ; our beast ) !
Phosphate cleaning is considerable less expensive, but is it good enough to prep surface ???
I’m concern about some resilient scaling not being removed by this method ( where a light sand blast will ) and only to later increase the chance to loosen the top coat by lack of adhesion !!

Any experienced advice would be well appreciated !
Thanks in advance, Amicalement Robert ;)

Sorry, forgot this link : See this
:o

I believe the worst thing about powder coating is that it is hard to touch up when you get the inevitable garage rash, ding etc. With paint it is easy to touch up and or grind some off, make a mod and then touch up again. I would stick to paint. Cheaper too. :)

I'm new to this and wanted to know the correct order of events between attaching the rack to the rails and painting and shimming of the rails.
Are the racks painted too?
And do you guys paint the v-rails separate and tape off the area where the racks attach?

Racks are greased, they don't get painted. The rails are fully painted and the tape attaches to the paint. We first paint the rails, then do shimming/tightentening down then attach racks.

Hi Robert,

Sandblasting is one way to go. The problem I found was that it does not reach those hidden places and it is very operator dependent. If the parts are thin and you are using the wrong media, they tend to distort. Pick the media carefully, shot blast is little iron slugs that beat the living daylights out of the steel. We used the stuff to harden torsion bars for some heavy equipment. Sand (carborundum) is very abrasive and can be found in different grades. Soft blasting can be achieved by using nut shells and is typically used on aluminium or soft body panels.

Hydrochloric acid (swimming pool stuff) can be used to strip rust and scale. Simply immerse in the stuff in a diluted form. Always add acid to water and not the other way round. It does not do anything but to remove rust and steel. The item must be rinsed properly to neutralise the acid immediately as it will start to rust in 10 min.

The problem with this acid is that it is highly corrosive and will attack anything near it. So don't use or store it in your garage, everything will have a nice, antique, rusty look.

Sulphuric acid actually penetrates the cracks in the scale and forms little hydrogen bubbles which pops off the scale in the first phase. That is the black stuff you will find at the bottom of your vessel. It then attacks the steel to form a nice clean surface. The longer you leave it, the more it will eat into the steel, forming a nice rough surface for the paint.

Seeing that it is Christmas, you can make your own snow using this method. The by-product of the process is iron sulphate, a nice, flaky, blue, white powder. Just create a saturated solution and put it in the fridge.

Phosphoric acid removes the scale as well, but additionally, it leaves a phosphate layer on top of the steel, which makes the paint stick better, but in itself it gives no protection to the steel. Phosphoric acid is also less aggressive than hydrochloric and sulphuric acid.

My recommendation is to use mechanical means to remove the worst of the scale. A rough steel brush or a flap disk in a grinder provides good results. After that I would use phosphoric acid to prep the steel before painting. Use an etch primer, touch the flaws up with body putty and give a coat of epoxy paint. Hammerite is also a good paint but it is very expensive.

The ultimate test for your paint project is to throw it down a mine shaft.

Jan….This is GOOD…I like reading this type of info…. I’m drooling….:D
Thanks a lot for your answer.
Amicalement, Robert ;)

metal filler to close pin holes on aluminium grilles all corners
 

We are currently powdercoating some parts for a company who is experiencing problems with pinholes in the welds and with lines and marks on the steel of the product. Our process is to sandblast the parts to remove the metal scale before powdercoating, but this is not removing these marks . This customer is very concerned about the smoothness of the finish and is wondering if there is anyway that we can fill these pinholes and smooth out the metal. We have not successfully found any type of metal filler that will withstand the temperatures needed to cure powdercoat and be unnoticeable after curing.

Does anyone know of such a product...

... or have any other suggestions? We have already suggested that they check with the welder to see if any of these problems can be eliminated before the parts ship to us, but they are still asking us to check in to using a filler of some sort.

Have a look at this . It has done miricle for me, many times.
Robert

Not used the product
 

But I found this:

http://www.thermobond3.com/index.cfm/HOME_PAGE

Regards

painting rails / masking the V profile?
 

I'm wondering what other builders have done for painting the rails. I understand that the V profile is left unpainted.

What's the best approach to do that -- apply a strip of masking tape and use a knife to cut off the excess that's wider than the V?

Michel - Yep thats about as simple as it gets, maybe use a small fine file to trim the masking tape - works better than a knife blade.