DIY Media blasting - is it worth the investment?

[TechnicalNut]

Hi folks,

I intend to bare metal the underside of my bus (it's already stripped down) and POR15 it. The painstaking wire-brush/wheel method fills me with dread, thus the media blasting idea popped into my mind.

Has anyone invested in a big hobby compressor & media blasting pot/gun to attempt anything similar?

From the information I've gathered, a 14cfm compressor is the minimum you can expect to get by with. Machine mart sell a 100 litre, 3hp, 14cfm compressor for £390. Ebay often has the blast media pot and gun at around £80, then I'd need the media, mask & tarpaulin. So I reckon there's somewhere around £600 invested for the job. Plus I estimate about 15 hours basting time!

I just can't see a wire brush or wheel doing as good of a job in all those hard to reach area's with as little effort. The compressor could then be sold to recover some costs, or used for air tools and a diy spray job at a later date. Of course if I went this route, I'd want a body roller to!

The majority of my blasting info was mainly gathered from here:
http://www.mig-welding.co.uk/sandblasting.htm

Your thoughts and experience would very much be appreciated!

Technut.

 

[BJ1]

My local sandblaster will do the underside of a van for around £100. Nuff said?

 

[noddy]

I agree with BJ1 the farmers round here use a mobile blasting service when they are repainting farm machinery, would cost you a lot less than buying your own kit. Just be careful which media is used the lead shot leaves a really rough finish which need to be hand flatted prior to paint, I know that some places use soda, a couple of Vdub restorers I have spoken to over the year say it leaves a really good surface finish.

 

[richbaker78]

I have a pot blaster as you describe (£80 ebay job) which i used for the above and was very succesful (i already had a compressor so not such an outlay for me). Its a really horrible job though and if doing it again I would pay someone as mentioned or if making and investment of £600 would probably get it dipped for a bit more on top.

Problem I found with blasting is that stuff gets inside the chassis rails etc which is difficult to remove. I think every process/ media has its drawbacks but my next projects defo being dipped!

After my fantastic sales pitch I am downsizing/ clearing my barn so will be flogging my pot blaster (cylinder type on wheels). £35 ono if your interested! its a handy tool in good nick but ive finished with it now and wnat it out the way. comes with loads of ceramic tips. ready to use.

 

[Guest]

soda works great, its mild enough to use on fiberglass. My bother has the kit for his boat but he uses a hefty industrial compressor. The outlay for the compressor is going to be the most expensive item. If you need one anyway then thats offset the cost in the long run.

I've seen media blasting with glass beeds and aluminium oxide, the soda is the best as theres less mess and residue can be easliy rinsed away. If you use sand or silicates make sure you have very good breathing aparatus ideally air fed as that **** can cause you all sorts of problems if it gets in your lungs.

Have a look at frost.co.uk for ideas, i think they sell a soda tank specifically for the job.

 

[ProfessorWheeto]

In my experience the cheap blasting guns aren't much cop anyway, your much better off just getting it done, its cheaper and its a grotty job anyway!

If you use sand or silicates make sure you have very good breathing aparatus ideally air fed as that **** can cause you all sorts of problems if it gets in your lungs.

I thought this was outlawed for those reasons? Could be wrong though.

 

[Guest]

I think it is, but ive still seen some 'professionals' using bags of play-sand from B&Q :shock:

 

[ProfessorWheeto]

:lol: :lol: :lol: :lol:
Obviously the ones that haven't twigged why soft sand is for kids and kiln dried sharp sand is for blasting... hope they don't charge an hourly rate!

 

[Guest]

:lol: :lol: :lol: :lol:
Obviously the ones that haven't twigged why soft sand is for kids and kiln dried sharp sand is for blasting... hope they don't charge an hourly rate!

yup, seen a guy buy loads of it cheap then wait to dry it out, tight or what!

 

[ProfessorWheeto]

:lol: Oh dear!