Which Expendable Media to use?

[deltacharlie26]

First post - be kind!

I want to blast a set of tractor wheels which have many layers of paint and some surface rust. I have a home brew pressure pot (similar to the Epay 20gall model) nearing completion and only 7cfm FAD @ 70psi available at the moment from a 3hp comp and 100litre tank. Using a 2.5mm nozzle which is the best media to use? Is my set up good enough for this task or do I need more air and a bigger nozzle. I intend doing this outside. Any help appreciated.
Regards,
Den

 

[bawjaws]

hey, welcome to the forum , i have no idea about blasting but theirs some good pages on it in this site somwhere, i think there in the practical section at the top of the page, ill go look!

edit- its actually in the paint section at the top, http://www.mig-welding.co.uk/sandblasting.htm

 

[Welderpaul]

Welcome to the forum. Forgive my ignorance...can you use kiln dried block paving sand? Would that be cheaper?

 

[bawjaws]

apparently the paving sand breaks down to a powder while using it and its nasty to the lungs, but ive never done it before so dont know what its like

 

[stormin]

Output sounds a bit limited for a 3hp compressor.

For blasting away rust on steel you need to be nearer 100psi for effective blasting. Doing it with a 2.5mm nozzle is really going to try your patience. Imagine trying to paint the wheels with a brush 2.5mm across. That's how slow it'll be blasting.

With that size nozzle you are probably looking at using Jblast supafine. You'll still need to seive it before use. You'll probably also want to try and recover it for re-use given the price. Kiln dried sand is cheaper but dangerous, once broken down and breathed in, causes lung problems.

Can't you borrow a bigger compressor for the job? The blast pots design is quite good, just needs a larger nozzle and more air for better performance.

 

[deltacharlie26]

Thanks for the welcome and pointers - looks like I am going to need more air and a bigger nozzle to do this job. What a great site this is for information. I just wondered what difference it practically made to use different media for removing heavy paint and surface rust on steel. I intend to try kiln dried sand (wearing mask etc) in the first instance (cos I have some) just wondered if JBlast supafine or some other media is better although any proprietary stuff would be safer, no doubt. I'm trying to skip a step in the learning curve, that's all.

I will probably farm out the wheels to a pro - been quoted £80 for two large 28" dia and two small 16" dia wheels does that sound reasonable? Any recommendations for a pro in the Birmingham area?
Regards,
Den

 

[Amit]

This stuff works well for me on alloy wheels.

http://cgi.ebay.co.uk/25Kgs-Expenda...14&_trkparms=72:1683|66:2|65:12|39:1|240:1318

Amit

 

[rtbcomp]

This guy for media in the Midlands - he'll sell it by the ton if you like!

http://shop.ebay.co.uk/merchant/pete_booth

Intersting info here, esprcially about using kiln-dried sand near the end

http://www.centurywise.co.uk/content/pdf/Guidetoblastcleaning.PDF

 

[deltacharlie26]

This stuff works well for me on alloy wheels.

http://cgi.ebay.co.uk/25Kgs-Expenda...14&_trkparms=72:1683|66:2|65:12|39:1|240:1318

Amit

Hi Amit,
What pressure and size nozzle do you use? Do you have a pic of one of your wheels?
Regards,
Den

 

[deltacharlie26]

This guy for media in the Midlands - he'll sell it by the ton if you like!

http://shop.ebay.co.uk/merchant/pete_booth

Intersting info here, esprcially about using kiln-dried sand near the end

http://www.centurywise.co.uk/content/pdf/Guidetoblastcleaning.PDF

Thanks for those links. The last one really shows how the pro's do it. Brilliant.
Regards,
Den

 

[rtbcomp]

Forgot to mention, I'm using the crushed glass grit at the moment. It does wear down but stills remains sharp. It works at about 60 psi with a 3.0 mm nozzle whereas I used 70 plus for the J-blast (AKA copper slag, iron silicate)

 

[Robotstar5]

I will probably farm out the wheels to a pro - been quoted £80 for two large 28" dia and two small 16" dia wheels does that sound reasonable? Any recommendations for a pro in the Birmingham area?

Have you tried this place?

 

[deltacharlie26]

Have you tried this place?

Just tried them, wanted £130 approx. Thanks for the link though.
Regards,
Den

 

[deltacharlie26]

Forgot to mention, I'm using the crushed glass grit at the moment. It does wear down but stills remains sharp. It works at about 60 psi with a 3.0 mm nozzle whereas I used 70 plus for the J-blast (AKA copper slag, iron silicate)

Can I ask what items you are blasting crushed glass at? I see its recommended for soft stone and non aggressive type cleaning, but I suppose you can use any grit on any job depending on what you are trying to achieve.
Regards,
Den

 

[rtbcomp]

Can I ask what items you are blasting crushed glass at? I see its recommended for soft stone and non aggressive type cleaning, but I suppose you can use any grit on any job depending on what you are trying to achieve.
Regards,
Den

I'm doing steel panel mostly. You have to be careful with Ally because sharp grit can embed itself in the metal.

These links may be of interest:

http://www.cosla.gov.uk/index.asp?pageId=100011005-11300116

http://www.glassadvantageinc.com/index.htm

http://www.esska-tech.co.uk/esska_eng_s/blast_material.html

 

[stormin]

What are typical prices for Jblast supafine?

A local supplier has quoted £14.99 per bag or £240 delivered for 30 bags (@50kg).
Don't know if it's a good price. Also lists something called Dirkblast at same price but reckons on 10-20% better efficiency.

 

[rtbcomp]

I paid £10.00 + vat for a 50 kg bag of Supafine, it's now packed in 25 Kg bags at £5.00 + vat from Hodge Clemco, cash & carry. AFAIK the iron Silicate Peter Booth sells is the same as Supafine.

What's Dirkblast?

 

[stormin]

I paid £10.00 + vat for a 50 kg bag of Supafine, it's now packed in 25 Kg bags at £5.00 + vat from Hodge Clemco, cash & carry. AFAIK the iron Silicate Peter Booth sells is the same as Supafine.

What's Dirkblast?

http://www.angloscotabrasives.co.uk/Abrasives.htm

This is the quote from their e-mail:-
"J Blast is in 50 Kg Poly sacks 30 to a pallet, (25 Kg bags are available in full pallets only at £15 per pallet surcharge)

Dirk Grade 2 is packed in 41Kg multi ply paper/poly sacks 35 to a pallet.

Note that the 50 kg bags of J Blast and the 41 Kg bags of Dirk both contain approx 29 litres so effectively there are 5 bags extra in volume on a pallet of Dirk, generally you will clean approx 10% to 20% more area per pallet using Dirk which is why we prefer to stock it in the finer grades, whilst in the coarser grades J Blast being more dense is usually more efficient on heavier contamination so we stock J Blast Supa for that purpose."

Both are @£240 per pallet.

Even at pallet rate dearer than coing to Clemco for individual bags. I may have to arrange a trip to Sheffield with a van or trailer, or price Clemco for a bulk delivery.

 

[rtbcomp]

Let me know and I can supply some coffee and show you my blasting setup

 

[Amit]

Hi Amit,
What pressure and size nozzle do you use? Do you have a pic of one of your wheels?
Regards,
Den

I used a clarke sb3 gun http://cgi.ebay.co.uk/CLARKE-SB3-GR...photoQQcmdZViewItemQQ_trksidZp1742.m153.l1262

and 90psi i think.

I dont have a pic of the wheels blasted sorry.

Amit