Sandblasting with 5hp air compressor. Please share your experience.

[MichaelP]

I've got a 5 hp 2-stage Quincy (15.4 cfm@100psi) and would like to hear your feedback on sandblasting using a similar compressor using a siphon media pickup.

What size of the jets did you try? What's CFM of your compressor? Can you describe performance of the combo?

Thank you.

Mike

 

[BinderRod]

I have about the same set up as yours. If you don't have a dryer hooked up that is a must. You will end up blowing wet sand and the tip will clog.
I was talking to the national paint and body rep for a major parts store and this is what he told me to do. This will cool the air slowly and eliminate moisture.


Where the hose comes out of the tank hook up a 50 fot air hose.

you can run it along the floor and loop it bact toward the compressor

Hook it to a deccasent dryer cartrige (HF for around 50 bucks)

Then hook your regulator and filter up.

Attach your air hose and your ready to blast with dry air


I have been using my blast cabinet with glass beads and it works great

 

[AdamMopar]

I have the same compressor. I use an ALC blaster with a 3/32" tip and the compressor will keep up. It will run quite a bit, but it does shutoff.

As previously stated, you do need to make sure you have a dry air supply. Ideally you will have a significant length of piping between the compressor and your first drop. Then a good water separator and filter.

As long as you have a dry air supply you should be fine.

 

[930dreamer]

I ran 50' of black pipe to a water seperator, regulator and the coalesing filter. After 8 hours of sanding plenty of water in the seperator, none in the coalesing filter.

 

[oltruckag]

I've done quite a bit of blasting using a similar setup - 2 "5hp peak" compressors connected together into a 60 gallon storage tank. The compressors could keep up pretty well, but I'd suggest getting a pressure blaster, not a siphon. Siphon blaster - sucked. Pressure blaster - AWESOME. Good rust and paint removal from sheetmetal and frames. 15 cfm is plenty of air for a small pressure blaster.

I've blasted 2 complete trucks with this one: HF 40lb blaster

 

[billspit]

I've used a siphon blaster for years. Use the narrowest tip made of the toughest material you can find. And replace it when it gets worn. A pressure blaster is well worth its cost over a siphon unit.

 

[MichaelP]

OK, let me put it this way. If I need to remove a moderate rust from one side of a 12" steel disc using my compressor and 3/32" jet on a siphon, how long will it take, approximately?

How about 1/8" jet? Should it even be considered with my CFM for occasional home shop use?

What's your personal experience?

P.S. I realize that a pressure pot will be much more effective, but I'm interested to find out if a siphon type blaster with my compressor setup will be acceptable for home shop situation. I'm not going to blast cars or other large panels. If I ever need it, I'll buy a pressure pot. I guess the largest part I may have will be something like brake discs, etc. The rest will be smaller, and I'll need blasting only occasionally. Maybe to clean a part or make a nice surface finish.

I read all about cfm per nozzle size, etc. and made my own calculations, but I'd like to get info from actual users. As for having air dry and approaches to piping, consider it done.

 

[oltruckag]

I found siphon blasters frustrating - even for a small amount of blasting it will blow lots of air, a bit of grit and slowly strip paint/rust. For one project, one time it'll probably be fine. But once you've blasted a couple of things (its quite handy for all kinds of things that need paint) you'll get frustrated and end up buying a pressure blaster.

Bottom line - smaller tip less grit/air, larger tip more grit/air. If you've got a 2 stage quincy it likely has a 60 or 80 gallon tank. You'll be able to blast with the larger tip, but you will have to stop and wait for the compressor to catch up. For occasional home shop use it will be adequate - just slow.

 

[e-tek]

Q1 - Answer is about 20 - 30 mins....depends on media used, how often your compressor needs to catch up, volume (cfm) actually going though blaster....

Q2 -Answer is about the same or longer. If you pinpoint the media you remove more rust but from a smaller area....also, the smaller jet may clog easier (?)

Would you do it outside, or try to do it in an enclosed space to reclaim the media?

 

[MichaelP]

In a cabinet.

 

[BinderRod]

Here is a before and after picture that I did in the blast cabinet.

http://picasaweb.google.com/BinderRod/BeadBlasting#5509531029914738306

 

[MichaelP]

What's the diameter of the opening in your nozzle? What's the cfm rating of your compressor? How long did it take to clean the part?

 

[dkroth]

I've used a siphon blaster for years. Use the narrowest tip made of the toughest material you can find. And replace it when it gets worn. A pressure blaster is well worth its cost over a siphon unit.

Thread hijack warning...

I have a sipon blaster and understand how that works.

How does a pressure pot blaster work? From the pics I've seen it looks like you'd be pushing A LOT more media out the hose and have to have LOTS of media on hand to refil the vessle (or reclaim, sift and reuse). Plus, I expect a pressure pot is for outdoor use only in a "remote" area so as not to foul your garage/shop/residence.

 

[milkovich]

it looks like you'd be pushing A LOT more media out the hose and have to have LOTS of media on hand to refil the vessle

Yep. But it goes A LOT faster then a siphon. It's the only way to fly if you have a car body or something else that can't fit in the cabinet like the stupid windshield channel on an A body. I probably did both channels with about 100 lbs of media in less than an hour.

As for the cabinet, I'm just using the same chinese one everyone is selling and have no problems with the gun that came with it. I bought a bigger siphon gun and that drains the 5hp two stage 80 gal compressor too fast. The cabinet works but it's SLOW on anything big like an intake manifold or a wheel. Just keep the nozzle size down and you can cruise along without waiting for the compressor. Make sure you strain your media every couple of uses too.

If you can find a blasting shop in town that will work for a REASONABLE ammount of money, it's easier to just drop big stuff off. The problem is there are so many guys that quote outrageous prices to walk-in cash customers. I've found industrial powder coaters usually have killer prices on blasting huge stuff like frames.

 

[lametec]

I use a hybrid set-up in my cabinet.

The gun is a regular siphon gun bought at Home Depot. Instead of having the siphon hose stuck in a bucket of media, I have it connected to a pressure pot filled with media. The pressure pot has a pressure regulator on it set very low, like 5 psi. Gun is fed air straight from the compressor at around 90psi.

The amount of media can be fine tuned by adjusting the pressure in the pot.

Works a treat.

 

[MichaelP]

Very interesting info, guys! Thank you.

Lametec, do you happen to have photos of your setup?

 

[lametec]

Doesn't really show anything useful, but it's a picture.

Yellow diagonal hose with qd on it plugs into the pressure regulator (tan piece on the right).

Yellow hose going into the cabinet is air supply for the gun. It tees off the input to the regulator.

Black hose going into cabinet comes from the bottom of the pot and goes to the siphon input on the gun.

 

[MichaelP]

Lametec,

Thank you. New to me and interesting approach! I wonder what was the rational behind making this kind of setup. Why not simply a pressure pot blasting confined in a cabinet?

What size of the bore does your tip have? What's the compressor CFM? How much media does your pot take and how long do you usually blast for before you need to recharge the pot?

 

[lametec]

A couple reasons. One, I wanted to use a smaller gun than the dead man valve that came with the pressure pot, the parts I blast are just too small to justify the huge valve/hose. And two, the pressure pot kept clogging.

I think running the pot at a low pressure (like less than 10 psi) helps keep it from clogging because the media isn't pushed against possible clogs as "hard". Not that it never clogs now, but since I'm feeding the gun air separately from the pot (and at a higher pressure), all I have to do is put my finger over the nozzle and pull the trigger and the pressure from the gun blows the media back into the tank, freeing up the clog.

A down side to my setup is that once you apply air to the pot, media comes out of the gun no matter what. I've considered making a simple nozzle blocker, but for as little as I use it, I haven't got around to it yet. For now I just keep my finger over the nozzle until I'm ready to blast.

I don't know what size tip I use.. whatever came with this kit:


Compressor is you average 60 gal/5hp, so about 10@90 psi.

Pressure pot is 110lbs capacity I got off eBay. Same as the Harbor Freight units (might even have come from there originally).

Since I don't blast big parts (blast cabinet is too small for that) I never really run out of media in a blasting session. At least not if I top off the pressure pot before I start.

Here's a sample of my results. Two different parts, but both looked about the same before I started:

 

[MichaelP]

Thank you.

 

[dodge610]

I do all my sandblasting in my fairly large beadblast cabinet have a 7hp 80 gallon craftsman professional compressor it keeps up quite well does not run all the time I have 3 moisture collectors one right off the compressor one about half way to the cabinet and one about 5 feet from the cabinet all get moisture but none in the cabinet my set up works fine just keep the moisture from the sand and blaster you will be fine.

 

[Tom2]

I have a 4hp compressor. 80 gallon tank, 2 stage, 175psi max 12.6 CFM at 90 psi. Husky from HD.

It's decent for sandblasting. Wish I had went a little bigger though.

I use a 110lb HF pressure pot for large outside stuff. Usually just run regular sand. Works good. Blasts paint and rust pretty well. The only water separator I use is the one that came with the pressure pot. Have never had a moisture problem.

I have glass bead in the cabinet. Since it's the syphon style, not nearly as much power. Usually I pressure pot blast really nast stuff outside, then put it in the cabinet for a quick polish.

The compressor will run non stop when blasting. I have to stop about every 5 minutes or so and let it catch up, or shut it down to cool off occasionally. If you can afford, definitely go bigger if you do a lot of blasting. One of the 7.5hp compressors that does 20+ CFM will probably keep up super well, run less, be quieter, blast more powerful, etc..

 

[Tom2]

I use a hybrid set-up in my cabinet.

The gun is a regular siphon gun bought at Home Depot. Instead of having the siphon hose stuck in a bucket of media, I have it connected to a pressure pot filled with media. The pressure pot has a pressure regulator on it set very low, like 5 psi. Gun is fed air straight from the compressor at around 90psi.

The amount of media can be fine tuned by adjusting the pressure in the pot.

Works a treat.

Yea, I run my pressure pot in my cabinet as well sometimes during the winter. Kinda hard to sandblast outside when there 2 feet of snow, etc.. Just had to enlarge the air inlet hole - then I use fender washers to fill the gap with the syphon hose.


I also replaced the deadman valve on the HF pressure pot. It's a joke. Blew the tip right off.

Another forum member here had made his own, I just copied the design:

Have had zero issues with it. Plus it's smaller and fits in the cabinet better.

As far as nozzle size, with a small compressor - go as small as you can without clogging.

 

[EricR.W.]

Thread hijack warning...

I have a sipon blaster and understand how that works.

How does a pressure pot blaster work? From the pics I've seen it looks like you'd be pushing A LOT more media out the hose and have to have LOTS of media on hand to refil the vessle (or reclaim, sift and reuse). Plus, I expect a pressure pot is for outdoor use only in a "remote" area so as not to foul your garage/shop/residence.

I hope this post about pressure sandblasters will help answer some questions: sandblasterinfo.com/equipment/pressurepot/