The Good, the Bad, and the Ugly, - Shotbasting

[locomad2]

For last 30 years I've always shotblasted model locomotives and stock for repainting, its quick, fun and certainly gets all the paint rust etc off for repainting. Even plastic using lighter shot blast materials, "crushed walnut shells" can be cleaned for repainting. With the price of shot blast guns been sold as little as £10 and decent compressor for less than £100. 

 

You can do it outdoors just make sure you wear suitable PPI or use a suitable cabinet (mine is old dish washer case). With a cabinet this saves shotblast material, can be done in a garage Grit, sand etc. I don't recommend inside the house the grit gets everywhere even with a cabinet.

 

Great advantage is models can be cleaned for repaint to a better standard, what I've got left in the scrap bin is those "harder" ones, thick car paint often several layers that require more air pressure, course grit.

 

Here's a typical example old Hornby Dublo body, no I didn't spray it came off a car boot.

 

 

Few minutes later getting there

 

 

Anyone else do this ?

 

 

[Enterprisingwestern]

 

Many years ago I worked for a company that dealt with the cleaning and refurbishment of aluminium machinery using crushed walnut shells. I took a whitemetal kit in and had it stripped, at a suitably low pressure obviously!, and the result was very good.

I've often considered it, but I've read reviews split 50/50 as to whether the machinery and equipment to do it in our smaller scales is satisfactory or not, so have always been put off somewhat.

What set up do you use?

 

Mike.

[locomad2]

Simple small shot blast gun with a bottle to hold the grit, and extra rubber hose on nozzle to clean small areas.

 

Remove the grit holder and replace with hose and stick other end on a container of grit which must be kept dry. I place a shelf of wire mesh (chicken wire) in an old dish washer case with holes blanked off. Whole point is to try and recycle as much of the  the grit as possible its horrible stuff flying around.

 

The rubber hose is brilliant in cleaning rusted bolts with excess thread just stick the whole thing over the bolt and press the button. I've used it to clean off small areas of damaged locomotive roofs etc without damaging rest of model, in the car repair industry used to clean metal for spot welding ie just a 1 inch diameter clean spot.

 

I've used professional blast cabinets at work, this why 30 odd years ago realised just how quick, cheap and easy once equipment set up. Professional ones have air extraction fitted, you can use a bagged hover at home, reason to remove fine dust, within seconds you wont see a thing if you don't do this.

 

I've used chemicals great for a one off, but very time consuming, very messy, costly, not easy to get the right stuff, when something has been painted a few times with thick hard enamel paint I found differcult to get paint off with even the most powerful paint stripper. I often find some bodies have had 5 or more "lives" as the paint comes off

 

 

 

 

[Crankpin]

Hi,

I've been using a shot blaster for a couple of rebuilds and I much prefer the dry technique to remove old paint. I bought a cabinet, which includes a gun, and already had a decent compressor, the smaller airbrush type can't shift enough air.

I originally had the Badger abrasive gun but found the small air hose insufficient to pickup the abrasive.  I used the badger grit, about 200 grit I think, but bought more from a seller online, which was a lot cheaper.

It shifts everything I've used it on, including enamels and cellulose.

The cabinet is situated in the garage but I still have to tape the lid as the stuff still gets out and will cover everything!!!!

The 47xx body has just been cleaned of all paint, this was cellulose.

Hope that helps.

Jeff

[locomad2]

Interesting I find too the dust is very fine, myself I use a vacuum to clear the cabinet but still the garage air looks very dusty so plan to place another outlet hose from the vacuum cleaner outside. I work dry, I do use a wet outside, brilliant for cleaning tougher jobs like land rover wheels, it also cleans drives lot quicker than just water.

 

Dry grit about 200 is what I use, more a car repair one, my hoze pickup about 1/2 inch, I do find grit needs to be very dry, even leaving grit in the cabinet can get damp it just won't pick up.

 

Notice your model is brass, when I blast mazak do find I have to rub down lightly after to avoid "muddle" effect, I use dry steel wool lightly, then blow dry using compressed air, accepts primer brilliantly and models done years ago don't chip. 

 

Next will be this 

 

[bluestag]

A chum has a very nice set up with a cabinet.   I've used it once, on a small 7mm loco.    I was thinking the grit stuck to the brass, and seemed to require a fiber brush to remove.

 

Now I have a rake of 6 wheel coaches to paint, and want to spray them as well.    There is concern among my mates that my end steps and other bits applied with super glue will be torn of by the blast.    I tend to doubt it, they seem to be stuck on well.

 

Any thoughts?

[Crankpin]

I did do some destruction testing to see what damaged I could inflict on an old body with some bits glued on. Some of them stayed on but others disappeared into the bulk pile of abrasive, retrieved later using a sieve.

I did clean off the paint off of a plastic wagon and there wasn't any noticeable loss of detail.

The cleaning works more by speed than pressure so it's not like breaking a foot step off when you picked up your latest creation, heavy handedly!!!

 

HTH.

 

Jeff