Shot Blasting Kit

[Martin350]

I'm just starting a partial restoration and recommissioning of an old car and there are going to be a lot of metal parts that I will want to clean and paint / repaint. Things like suspension components, exhaust manifold, brackets etc.

I was thinking of gathering as many parts as I could at a time and take them to someone who could shot blast them clean for me.

Then I thought, why not get a kit and do it myself?

I would appreciate anyone's knowledge and experience of shot blasting equipment.
What should I expect from certain kits, are there any features I should look for?

I have a reasonably large air compressor (although I'll have to check the cfm rating again as I can't remember off the top of my head) and was thinking along these lines;

https://www.google.co.uk/shopping/product/47266637...

https://www.google.co.uk/shopping/product/28867883...

Thanks!

[Mr2Mike]

You really need to think about some form of dust extraction when using a blast cabinet. The cheap cabinets often come with just an air filter, and these tend to get blocked up literally within a few minutes, and don't actually remove the dust inside the cabinet so you can't see what you are doing after a few seconds.

[paintman]

Needs to be a substantial compressor too.
Having had a play with a spot blast gun with smaller ones I'd have done better throwing the media at the surface.

[Martin350]

Ah, I hadn't considered extraction.

And yes, the more I've looked into it the more it seems I need a compressor at least twice as powerful as the one I have.

Oh well, thanks guys, it was a nice thought while it lasted!

[tapkaJohnD]

Martin,
It's expensive, but a SnapOn Crud Thug might be an investment for a whole car restoration.
Specified air consumption, 4cfm, within most reasonable compressors.

They look like a wire wheel, but work differently, like a scale removing needle gun, to get into minute crevices.
See: https://www.youtube.com/watch?v=OXTLYeDY6fI

John

[paintman]

An interesting variation on a wire wheel - a few videos on youtube worth watching - but its size will make access into tight areas such as the suspension components mentioned by the OP impossible - blaster has no such problems.

The snap-on tool requires 4cfm at a constant maintained 90psi which is a lot of air.
Many compressor ads are frankly cons in that they list air displaced, NOT free air delivery which is the important one & is considerably less than the displacement. They also show max operating pressure but fail to mention that that is not what the compressor can put out continuously. Usually results in disappointment for people buying them and expecting to run air hungry tools such as grinders, sanders, rattle guns, blasters etc.

Edited by paintman on Sunday 31st July 23:03

[Bodo]

Also, especially compressors for private or SB use have their motors rated at less than 100% duty ratio.
Still, it's possible to cluster inexpensive compressors in parallel (makes sense if they are used rarely), in case a higher output (=air delivery) is required. No need to run a screw compressor, if the shot blast cabinet is used on weekends only.

[tapkaJohnD]

There is an electric version: http://www.mbxit.com/products/bristle-blaster/elec...

JOhn

[buzzer]

Dont discount a blasting cabinet... one of the most useful things I have for restoration. While I would never bother with suspension parts, manifolds and large stuff, for small things it makes a HUGE difference. As an example I have just cleaned a rare fuse box for a guy... Its brass and Bakelite, and looked a real mess. after it was de-greased (an important part) I gently blasted it on a very low pressure with fine glass bead. It came up like new. Brass and plastic were shiny.

Mr2Mike is right about extraction though... mine uses a plastic storage box which I have to empty after say 10 hours of use, but even then there is not a lot in there. it vents outside.

On the compressor side, yes you need a reasonable one, but storage capacity is as important as anything. My 9cfm compressor with a small tank is a waste of time on its own, but couple it with a large calor gas bottle as a storage tank and its fine. The calor gas bottle sits outside of the garage at the back, with a pipe through the wall. I can see the H&S guys sucking their teeth and getting ready to type... but the cylinders are pressure tested to over 250 PSI, and I only run at 120. Its been out there for 10 years... and the one before that (it got quite rusty) about 20 years!

I use both glass bead and Aluminium oxide in mine, takes 5 mins to swop over, or a bit longer going from oxide to bead as I like to get ALL the oxide out so as not to contaminate the bead. I often blast components with oxide first, and finish them off with bead. this gives a great finish, that last a lot longer and wipes clean as the bead peens the surface and seals it.

One tip with glass bead is to use as low a pressure as cleans what you are blasting... Dont be tempted to turn up the pressure... this shatters the glass bead and causes loads of dust. that way the bead will last a long time.

another tip is to use some 3M paint protection film on the underside of the glass in the cabinet. I have a piece on there that has lasted a couple of years! if you have no protection, the glass frosts after a short while and you cant see what you are doing!

Here is my cabinet, you can see the plastic storage box underneath used as a large filter (there is nothing in there, the heavy dust particals drop to the bottom, outlet is at the top) it vents out of the wall. Made with plastic sink waste.



here is a before and after of a carb restoration.

Edited by buzzer on Monday 1st August 10:10

[Martin350]

Thanks for all of the useful and interesting posts, they've certainly given me a few things to think about.

[Mags]

I bought the latter of your 2 ebay links a few years ago, but from Miller blasting: http://www.millarsodablasting.com/
I restored my VW Type over several years at a farm where I rented some space. I originally used the Archifine media they sell but it was so fine it created huge amounts of dust and was a pig to recycle. I tried a couple of other, cheaper materials and eventually used a glass bead, I think I also drilled out the metering unit a little in an attempt to use a coarser and cheaper media, see here: http://www.mig-welding.co.uk/forum/threads/blastin...
Typically after blasting the entire underside of my bus with the Archifine stuff I only discovered the glass beads later on but they made the blasting of all the suspension components etc much easier with great results and easier to sweep up and recycle.
Although I blasted the underside of my bus inside a barn, it created so much dust I bought a good quality full face mask/breather and ended up creating a kind of sheeted off area with a big fan at the end sucking the dust to the outside. I found the glass beads much better, but I only ever blasted outside other than the bus itself.
I hooked up a few large tarps so most of the media fell onto these making it less messy and easier to sweep up and recycle. However, I was still on a farm, I don't think I'd ever try this at my house!
Before

During/after (painted with epoxy)

[Martin350]

Hi.

Sorry for the delay, I've been away and without internet.

That looks great, thanks for the post, very useful and interesting.

Do you know the stat's on the compressor you were using?

Thanks.

[Mags]

I'm afraid not but it was pretty big, and even then I had to pause every now and then to allow it to catch up. Blasting suspension parts etc was fine as you tend to stop/start a lot, blasting the whole underside of the VW was a very slow job.

[Martin350]

Ok, thanks.

I suspect my 1.5hp compressor won't stand a chance.

Wire brushes in the drill and a load of wet & dry it is then!