This is a how-to for polishing; in this write up we’ll polish an Eaton m112 supercharger
First off you need to remove then disassemble the supercharger, remove the pulley while it’s still on the car. Once it’s off the car remove the bypass valve, sensors and anything else bolted on, intercooler included. At this point you can strip the paint, or do it later, notes below on this step.
Next you’ll need to disassemble the blower; it’s as easy as unbolting the snout and pulling it off. Once you get the snout off you’ll need to pull the middle section out, the rotors will come with this section.
Now that you have the blower in 3 pieces you can either go all out and break each piece down EG removing the gears, shaft, etc, or just tape off areas.
It’s far simpler to tape off areas, so once you’ve removed the gasket maker on the edges of the snout, middles section and case; you can seal those off with duct-tape. Tape the back of the snout, the gear side of the middle section, then on the rotor section you can wrap the rotors in bubble wrap, then tape them up completely, you want to seal all internal areas with tape. Clean the interior of the case out with acetone on a rag, and carefully clean the area around the rear bearings, tape those off now, you can’t let anything get into those bearings.
Now that all the internal parts of the blower are sealed you can strip the paint off, just brush air craft finishing remover, and let it sit for 10 minutes, then wire brush the paint off. You can also do this while the blower is still assembled.
Now that the paint is removed it’s time to start sanding. I use a 2hp polishing machine with specific sanding grit wheels, this is not practical for the weekend warrior, so I’ll explain the sanding process using simple tools, if you’re curious about my specialized polishing machine feel free to PM me, it’s about a $800 investment and will cut a 20 hour polishing job down to 2 hours.
First step in sanding is to select your sand paper, home depot sells 20 sheet packages, and you’ll want a lot of paper, buy 80, 120, 200, 300, and 400. You might need to visit an automotive store for the finer grits; you’ll need 600, 800, 1000, and 1500.
You’ll need a sanding block, a vibrating palm sander, (not an orbital sander) and some small prices of wood you can wrap in sand paper. A dremel with some pointed cone sanding bits and some drum sander bits will save you a lot of time, nothing over 150 grit for this though. Also you’ll want some dremel bit buffing wheels.
Start sanding, the flat areas of the blower are easy to hit with a palm sander, start with 80 grit and do as much as you can, getting the hard to reach places are tough, you can wrap sand paper around small pieces of wood to get into those areas, or you can try the dremel. For this project a dremel is a skill tool, too high an rpm in one spot one second too long will cause a low spot, you don’t want this, so be very careful sanding with this tool.
Take your time sanding, once you’ve sanded the whole blower to 80 grit you need to continue to 400 grit, it’s going to take a long time, but the finish product is only as good as this preparation.
So now you’re finished sanding up to 400 grit; by now you’ve probably figured out how to get into the small areas of the blower, if not get creative, worse case is you’re just balling up sand paper on the end of your finger, sometimes you have to get that crude for the sake of the finished product.
Now it’s time for wet sanding. I like to mix water and dawn soap into a spray bottle and use that as the liquid, not only does it keep the sand paper free of debris, it cleans the metal as you’re polishing. You can continue to use the palm sander but the dremel is worthless for now. Wet sand 400, 600, 800…
You’re probably tired by now, you can stop wet sanding at 800 if you’d like, but for that little extra bling in the finish continue up to 1500 then even 2000 if you’d like.
Now that you’re done sanding it’s time to clean the blower, make sure nothing is on it, use acetone to clean the whole thing, you should be left with a smooth looking dull surface.
Ok here is what you’ll need for polishing, I highly suggest a bench grinder, the more amps the better. The key to polishing is being able to force the part onto the polishing wheel while keeping wheel speed constant creating heat and slowly moving over the part, you can most defiantly use a hand drill too.
If you’re using a 1/3rd hp bench grinder 5” wheels are good, a drill use 3” wheels, on my 2hp polishing machine I use 8”-10” wheels. The wheels you’ll need are spiral sewn cotton wheels, look them up on yahoo, you’ll want atleast 3 since you can’t mix compounds over different wheels, 6 would be better just incase you ruin one. You’ll also want several dremel polishing wheels, these ware out fast so get them in sets of 3.
You’ll need 3 polishing compounds, these look like crayons, Emory, Tripoli, and White rouge.
If you decided to use a hand drill sears sells a polishing kit in their dremel section, it comes with 3 wheels, and 4 compounds, this will also work.
Start polishing, put a wheel on your buffer, bench grinder, or drill, get it spinning and press the Emory compound to the wheel. What happens is the friction of the wheel melts the compound down and it sticks to the wheel. Slow even movements are essential, building heat is ideal. Do as much of the blower as you can, for the small hard to reach areas use the dremel with a polishing wheel on it, same process.
At this point the blower should start looking like this.
Wipe all the polished surfaces with acetone, now using a new wheel repeat the whole process using the Tripoli compound.
Again wipe the blower down with acetone and repeat the process once again using the final compound, white rouge.
Now you should have something that looks like this
Clean the blower out like mad, you can’t leave any shavings or compound on the blower, wipe it with acetone, use an air compressor to blow anything out of it.
Remove all the taped off areas, clean the edges to prep them for new gasket maker, I also picked up a can of high temperature bearing grease and added a little more to the rear bearings.
You’re ready to reassemble the blower, line a bead of copper gasket maker on the front of the case, slide the rotor section of the blower into the case, do it slowly and carefully, don’t force it, push it until it’s flush up against the case.
Next the front of the section you just pressed in with gasket maker and press that in, make sure you line the snout coupler up with the gear, press it all together.
Now 18tq each bolt back into the snout, do a zigzag pattern to lock it down evenly.
Once it’s back together let the gasket maker cure for a while, you should be looking like this
Now add some oil, you can just 5w-30, that’s what I used.
Put it all back together and put it on the car
If you have more questions PM me
First off you need to remove then disassemble the supercharger, remove the pulley while it’s still on the car. Once it’s off the car remove the bypass valve, sensors and anything else bolted on, intercooler included. At this point you can strip the paint, or do it later, notes below on this step.
Next you’ll need to disassemble the blower; it’s as easy as unbolting the snout and pulling it off. Once you get the snout off you’ll need to pull the middle section out, the rotors will come with this section.
Now that you have the blower in 3 pieces you can either go all out and break each piece down EG removing the gears, shaft, etc, or just tape off areas.
It’s far simpler to tape off areas, so once you’ve removed the gasket maker on the edges of the snout, middles section and case; you can seal those off with duct-tape. Tape the back of the snout, the gear side of the middle section, then on the rotor section you can wrap the rotors in bubble wrap, then tape them up completely, you want to seal all internal areas with tape. Clean the interior of the case out with acetone on a rag, and carefully clean the area around the rear bearings, tape those off now, you can’t let anything get into those bearings.
Now that all the internal parts of the blower are sealed you can strip the paint off, just brush air craft finishing remover, and let it sit for 10 minutes, then wire brush the paint off. You can also do this while the blower is still assembled.
Now that the paint is removed it’s time to start sanding. I use a 2hp polishing machine with specific sanding grit wheels, this is not practical for the weekend warrior, so I’ll explain the sanding process using simple tools, if you’re curious about my specialized polishing machine feel free to PM me, it’s about a $800 investment and will cut a 20 hour polishing job down to 2 hours.
First step in sanding is to select your sand paper, home depot sells 20 sheet packages, and you’ll want a lot of paper, buy 80, 120, 200, 300, and 400. You might need to visit an automotive store for the finer grits; you’ll need 600, 800, 1000, and 1500.
You’ll need a sanding block, a vibrating palm sander, (not an orbital sander) and some small prices of wood you can wrap in sand paper. A dremel with some pointed cone sanding bits and some drum sander bits will save you a lot of time, nothing over 150 grit for this though. Also you’ll want some dremel bit buffing wheels.
Start sanding, the flat areas of the blower are easy to hit with a palm sander, start with 80 grit and do as much as you can, getting the hard to reach places are tough, you can wrap sand paper around small pieces of wood to get into those areas, or you can try the dremel. For this project a dremel is a skill tool, too high an rpm in one spot one second too long will cause a low spot, you don’t want this, so be very careful sanding with this tool.
Take your time sanding, once you’ve sanded the whole blower to 80 grit you need to continue to 400 grit, it’s going to take a long time, but the finish product is only as good as this preparation.
So now you’re finished sanding up to 400 grit; by now you’ve probably figured out how to get into the small areas of the blower, if not get creative, worse case is you’re just balling up sand paper on the end of your finger, sometimes you have to get that crude for the sake of the finished product.
Now it’s time for wet sanding. I like to mix water and dawn soap into a spray bottle and use that as the liquid, not only does it keep the sand paper free of debris, it cleans the metal as you’re polishing. You can continue to use the palm sander but the dremel is worthless for now. Wet sand 400, 600, 800…
You’re probably tired by now, you can stop wet sanding at 800 if you’d like, but for that little extra bling in the finish continue up to 1500 then even 2000 if you’d like.
Now that you’re done sanding it’s time to clean the blower, make sure nothing is on it, use acetone to clean the whole thing, you should be left with a smooth looking dull surface.
Ok here is what you’ll need for polishing, I highly suggest a bench grinder, the more amps the better. The key to polishing is being able to force the part onto the polishing wheel while keeping wheel speed constant creating heat and slowly moving over the part, you can most defiantly use a hand drill too.
If you’re using a 1/3rd hp bench grinder 5” wheels are good, a drill use 3” wheels, on my 2hp polishing machine I use 8”-10” wheels. The wheels you’ll need are spiral sewn cotton wheels, look them up on yahoo, you’ll want atleast 3 since you can’t mix compounds over different wheels, 6 would be better just incase you ruin one. You’ll also want several dremel polishing wheels, these ware out fast so get them in sets of 3.
You’ll need 3 polishing compounds, these look like crayons, Emory, Tripoli, and White rouge.
If you decided to use a hand drill sears sells a polishing kit in their dremel section, it comes with 3 wheels, and 4 compounds, this will also work.
Start polishing, put a wheel on your buffer, bench grinder, or drill, get it spinning and press the Emory compound to the wheel. What happens is the friction of the wheel melts the compound down and it sticks to the wheel. Slow even movements are essential, building heat is ideal. Do as much of the blower as you can, for the small hard to reach areas use the dremel with a polishing wheel on it, same process.
At this point the blower should start looking like this.
Wipe all the polished surfaces with acetone, now using a new wheel repeat the whole process using the Tripoli compound.
Again wipe the blower down with acetone and repeat the process once again using the final compound, white rouge.
Now you should have something that looks like this
Clean the blower out like mad, you can’t leave any shavings or compound on the blower, wipe it with acetone, use an air compressor to blow anything out of it.
Remove all the taped off areas, clean the edges to prep them for new gasket maker, I also picked up a can of high temperature bearing grease and added a little more to the rear bearings.
You’re ready to reassemble the blower, line a bead of copper gasket maker on the front of the case, slide the rotor section of the blower into the case, do it slowly and carefully, don’t force it, push it until it’s flush up against the case.
Next the front of the section you just pressed in with gasket maker and press that in, make sure you line the snout coupler up with the gear, press it all together.
Now 18tq each bolt back into the snout, do a zigzag pattern to lock it down evenly.
Once it’s back together let the gasket maker cure for a while, you should be looking like this
Now add some oil, you can just 5w-30, that’s what I used.
Put it all back together and put it on the car
If you have more questions PM me
Last edited:
