OzVMX Forum

Clubroom => Tech Talk => Topic started by: brad747 on May 24, 2008, 11:43:22 am

Title: Blasting parts!
Post by: brad747 on May 24, 2008, 11:43:22 am
Hey,
I need to get my parts blasted! What will be the best option for each part?
Like is sand blasting ok for use on hubs, tripple clamps and engine cases and barrel/head??
thanx
Title: Re: Blasting parts!
Post by: VMX247 on May 24, 2008, 11:50:53 am
there are a few options now!
couple of guys(WA) have just set up bicarb blasting off the back of there ute,doing
pushbikes through to tractors and power station parts,locals are saying if does a beautiful job.
Then you can also get garnet blasting.
Shop around and get plenty of opinions
cheers
Title: Re: Blasting parts!
Post by: cyclegod on May 24, 2008, 12:31:30 pm
Steel parts = sand blast
Aluminium / Magnesium parts = glass bead blast
Title: Re: Blasting parts!
Post by: Lozza on May 24, 2008, 06:25:37 pm
Latest thing is Vapour Blasting that leaves an almost shiny finish.
Title: Re: Blasting parts!
Post by: suzuki27 on May 24, 2008, 07:55:07 pm
I was warned by a mechanic NOT to to use Silica/Glass bead blasting for internal engine parts.The small and abrasive particles are prone to become lightly embedded in the alloy and slowly work there way out again where they result in premature internal engine wear.This was witnessed by a career M/Cycle mechanic on a freshly ground up rebuild of an 83 GS1000/1100-the motor had to be rebuilt soon after due to the abrasive wear done to this motor from the Glass/Silica bead used to strip this motor prior to rebuild.Fine for External use but NOT for internal parts.
Title: Re: Blasting parts!
Post by: pmc57 on May 24, 2008, 08:45:38 pm
Glass bead blasting is fine for any material you don't want damaged by more abrasive mediums like garnet or worst still, sand. These include aluminium and magnesium housings and to some extent the ground finish on lightly scored/scuffed crank shafts before re-polishing of bearing and seal areas.
Internal parts as Suzuki27 suggested I feel are fine to blast with glass as long as you make sure parts are FULLY dismantled before being blasted so glass beads don't get lodged in hard to get places and can't get cleaned out. When blasting is complete, all part should be throughly washed in a suitable solvent to remove any residual glass dust and blown dry, then all threaded holes should be re-taped to clean out threads and machined mating surfaces should be rubbed or lapped on a surface plate of 600 grit + wet and dry to ensure full sealing of gasket faces is achieved on reassembly. These proceedures should be normal practice during all engine rebuilding to ensure an accurate and efficient assembly.
Remember, if you can't fully dismantle an item and remove every nut, bolt, bearing, seal, shaft, circlip (everything) then don't blast it, those beads get in everywhere.
It all comes down to how particular you are with your cleaning and pre-assembly stages that determines  the success of the final result of the piece of equipment you are rebuilding.   
Title: Re: Blasting parts!
Post by: Tim754 on May 24, 2008, 09:51:29 pm
C4 ;)
Title: Re: Blasting parts!
Post by: Nathan S on May 27, 2008, 11:23:53 pm
I've glass bead blasted a lot of engine bits, and not had a drama.
I put everything through the "hot tub" at work, both before blasting and after. The 'before' clean is actually far more important than you'd think - the only time I've had dramas is when there was left-over oil/grime for the abrasive media to stick into. It took a lot of time and effort to clean it all out...

Title: Re: Blasting parts!
Post by: carbyman on June 08, 2008, 02:55:39 pm
We have a machine that does mass finishing or steel ball burnishing once the parts have been bead blasted they go into the machine and it polishes them but not to a mirror finish it doesn't remove any material
look at the link below for some pictures of my 83 kx parts that have been done
http://www.xtremefuelsystems.com.au/gallery.php?g2_itemId=43
Title: Re: Blasting parts!
Post by: Rossvickicampbell on July 04, 2008, 01:03:45 pm
usually its a case of why blast internally anyway?????  If you want to paint the item then fine sand blast is the way to go as it leaves a real good surface key for the paint to stick to - if you are looking for a "natural" finish the bead blasting is the way to go.  More likely to find shops that can do either of these than water blasters etc anyway.  If the shop is a specialist blaster they should be able to take just a coat of paint off etc!

Rossco