I want to sand blast my intake manifold to get some paint off that some one did a quick job on. I believe so long as im not trying to to cut through i should be ok, what do you guys say?

 

Be very careful :yesnod: Aluminum is very soft and will abrade away quickly. Clean and then cover with duct tape ( yes, duct tape) all machined surfaces. Cover carb area, thermosat and distributor mountings.

Start farther away when blasting, and don't stay in one area too long. Turn down the air pressure too.

:seeya

 

I was going to go with masking tape, but duct tape it is. I am running about 120lbs of pressure with real fine sand just enough to knock off the bad pait job i hope :confused: but ill make sure i keep my distance and keep moving what do you think :D

 

I use about 30 psi and hold the nozzel at a 45 degree angle.The main problem is stuck on paint. The area around the paint will go away leaving and island where the paint remains.I have never tried it but my machinist uses glass bead.seems to work much better.

 

Aircraft people use Walnut Shells on aluminum.......pistons, etc................

 

I always use #6 glass beads and 80 pounds of pressure and it will NOT harm the aluminum intakes. I can make an old intake look new. For the very final finish change the glass beads to new beads and the intake will come out looking shiny, that new look then coat with clear lacquer. I do this every couple of years to keep my intakes looking new.
I have never used sand so I don't know how well it cuts but I can't imagine it cutting through the intake.
Be very careful with clean up later. If any pocket retains sand and you install the intake it will take the bearings out immediately.

 

While sand can damage auto sheet metal panels it will not harm aluminum castings such as an intake manifold . The use of glass bead as a cleaning medium will provide excellent results and as Norval pointed out a final pass with clean beads just adds that new look . Walnut shells are excellent to use as a cleaning medium on parts where you do not wish to change the surface texture . Eastwood has a guide in their catalog with info on the use a number of different blasting mediums . In addition to masking the the various openings in the manifold it is also a good idea to plug any bolts holes such coil mounts etc . The beads are a bugger to get out other wise .

geo


[Modified by ram82fire, 8:11 AM 9/13/2002]

 

Glass beading is the ONLY way to blast aluminum....if u use sand, kiss the piece adios

 

Ideally glass beads or walnut shells should be used as described above. I've just bead blasted an aluminium head & as it was taking ages to clean up, I swapped to sand & set the pressure to 80psi :eek: It worked well in getting rid of the burnt oil, old paint, oxidation, etc & I finished off with clean glass beads (although it looked pretty good after sand blasting). I usually mask up with electrical insulation tape or masking tape (the most time consuming part of the job), but have never tried duct tape. It is imperative to thoroughly clean up afterwards (many an engine has been wrecked due to glass beads or sand being left in a little nook or cranny & then leaping out at 5000rpm to do its worst). A good way to really make sure that it's all cleaned off is to put the piece in a large metal container full of water & boiling it for an hour or so (the wife/GF needs to be out of the house for that!). Then a jet wash to be sure.
Prior to blasting make sure that there is no RTV on it as it's really good at masking up the metal.
:cheers:
edit: The sand I used was a very fine type used by builders for ornate pointing. I was amazed at how well it worked, having seen the results of alloy that was sand blasted with the normal sand/shot blast used for cleaning ferrous metals :( If you use sand, try it on an old casting or an out of sight area 1st to check that you like the finish it gives & that it doesn't eat away the alloy. The finish I got was a dull uniform colour which is far from the shiny new look. But the head will be far easier to keep clean now as the microscopic rough edges/pores have been flattened out slightly, so won't hold dirt so easily.


[Modified by UKPaul, 3:25 PM 9/13/2002]

 

I am not sure if you want to polish your intake or just remove paint? For paint I used paint removever , it was easy and really work for me. :yesnod:

 

I only use glass beads for aluminum.

 

I use a fine sand media at 100 psi and it has worked well on aluminum intakes. Gives it a nice polished look. As with anything, you have to pay attention and not stay in one area too long.

 

I used Busch Clear Coat remover on my aluminum valve covers, it's actually made for aluminum rims but it worked fine...just make sure you have protection on it can be nasty stuff.