Poor Man's Air Blaster

[Nandomas]

:thumbsu: :Bananasaur:

Thanks TOM!

[squalicorax]

thanks tom too!

Im doing this right now with a Paasche AECR

I like the shopvac idea.

Anyone have any thoughts on powered pumice?

[FossilDAWG]

Thanks for a great discussion, all. I just picked up a Paasche air erasor kit (the kind with the 15 CC reservoir on top, and am now wondering about an appropriate compressor. I assume one would be working at 20-40 psi most of the time, although the unit is supposed capable of up to 65 psi. Mostly I just hope to clean up some Arkona crinoids (very soft shale) and give a final cleaning to some Verulam Formation trilobites (medium soft shale, some thin limestone) and similar sorts of projects. Is an oil-less compressor preferred over one that uses oil? And what sort of capacity would be optimal? I imagine it would be annoying to have the compressor running all the time I'm working, so one of the 2-3 gallon units might be too small, but on the other hand perhaps an 80 gallon capacity would be overkill (on the budget too!). What have people found that works well for them?

Thanks,

Don

[Northern Sharks]

Thanks for a great discussion, all. I just picked up a Paasche air erasor kit (the kind with the 15 CC reservoir on top, and am now wondering about an appropriate compressor. I assume one would be working at 20-40 psi most of the time, although the unit is supposed capable of up to 65 psi. Mostly I just hope to clean up some Arkona crinoids (very soft shale) and give a final cleaning to some Verulam Formation trilobites (medium soft shale, some thin limestone) and similar sorts of projects. Is an oil-less compressor preferred over one that uses oil? And what sort of capacity would be optimal? I imagine it would be annoying to have the compressor running all the time I'm working, so one of the 2-3 gallon units might be too small, but on the other hand perhaps an 80 gallon capacity would be overkill (on the budget too!). What have people found that works well for them?

Thanks,

Don

Well Don, soundds like you'll be doing the same material I normally work on, although I haven't found any nice complete Arkona crinoids yet. I have a Comco unit and clean my Verulam trilobites at about 80 psi and use crushed limestone as an abrasive. The same works well on Arkona trilobites and brachs, Silica trilobites and NY trilobites, and anything else from the Verulam. My tank is an 8 gallon Campbell-Hausfeld and it came as a kit along with a nail gun, spray painter, air hammer and a few other things. It runs often, but not constant, and more frequently with the air scribes than with the abrasive unit. It is an oil using compressor. The big thing is getting a good air dryer, as moisture in the abrasive bungs the nozzle and slows everything down.

Edited December 8, 2011 by Northern Sharks

[TOM BUCKLEY]

thanks tom too!

Im doing this right now with a Paasche AECR

I like the shopvac idea.

Anyone have any thoughts on powered pumice?

Be aware that the Paasche AECR with the 1 quart remote canister will not work with our abrasives. I was informed by Paasche that they too had learned that the remote unit only works with denser powders such as aluminum oxide. My AECR is on the shelf until I can come up with a workable modification. I asked Santa for a Vaniman unit. :jig: :jig: :jig: In the meantime....I'll keep using the one with the little cup.

I've found that pumice, at a MOHS hardness of 6, is overkill for my typical work which is trilobites in soft to hard shale. Aluminum trihydrate at 2.5-3.0 MOHS hardness is my abrasive of choice. Its just a tick under calcite (3.0 MOHS hardness and the material that trilobite exoskeletons are made of) in hardness so it's perfect for what i'm doing. I typically use 60 micron but if I need more aggressive abrasive action, I can go as high as 125 micron and bump the air pressure from 25-30 to 50-60 lbs.

Tom

[squalicorax]

Hey thanks Tom for the advice.

Can I use powered dolomite or limestone or the Aluminum trihydrate with this unit?

I should mention I am mostly prepping Limestone and Shale fossils.

Edited December 9, 2011 by squalicorax

[Malcolmt]

I am using the same paashe as you bought with Dolomite or baking soda (just Arm and Hammer). Never use the aluminum oxide as it cuts too much. Have never found a Canadian source for the Aluminum trihdrate.The dolomite is a little softer than the baking soda and does not have as sharp edges. I managed to pick up a 20 kilo bag of the dolomite from a sandblasting business who was willing to sell me just one bag. He also gave me some greeb glass beadshe uses to try but I did not like them as they left tiny pits in the fossil.

I still find that I use my Paashe (I have 2) more than my two much more expensive dental units as it is quick to use and I really only use the air abrasive for the very final clean up. Works extremely well on Arkona material, Veralum material and Windom shale trilos.

I am using a Porter oiless compressor that cost about $200 up here in Canada. Works very well with my scribes and units I have like 9 quickconnects hooked up via blocks and splitters. Running One line at 35 PSI for the abrasion units and one line at 90 PSI for the scribes. An Air filter water trap on each main line is a must. Also you need to empty the condensate from the bottom of the compressor tankk every few days.

Edited December 9, 2011 by Malcolmt

[TOM BUCKLEY]

Hey thanks Tom for the advice.

Can I use powered dolomite or limestone or the Aluminum trihydrate with this unit?

I should mention I am mostly prepping Limestone and Shale fossils.

I've tried aluminum trihydrate and it doesn't work in the AECR unit. I don't remember but i'm pretty sure dolomite didn't work either. If you're looking for increased capacity you'll need to move to a Vaniman or Integral unit.

If I get the Vaniman for Christmas, I'll report back on how well it works.

Based on discussions with Paasche and my experience, the only abrasive that works with the AECR unit is aluminum oxide.

Tom

[squalicorax]

Thanks Tom,

Ill have to return the AECR unit as it hasnt even been delivered yet and I will order the kit here http://www.amazon.com/Paasche-Airbrush-AEC-K-Abrasive-sprayer/dp/B001CJIHFI/ref=pd_sim_sbs_ac_5

Any reccomendations to source powdered limestone or dolomite.

Also this kit contains a moisture trap, will this suffice for one on my setup?

Will this powdered limestone suffice if I screen it before use http://www.amazon.com/Calcium-Carbonate-Powder-Acidity-Limestone/dp/B0034UJ2VG/ref=sr_1_sc_1?ie=UTF8&qid=1323443728&sr=8-1-spell ?

Thanks

[Malcolmt]

The limestone looks to be too coase to me. The dolomite I am using cost me $20 for 20 kilos from a local sandblasing company I just looked up in the phone book and called around till I found one that would sell me a bag. It comes screened to about a 60 mesh which I then rescreen to 80 and then again 100 . I throw the material away that wont go through the 80 mesh screen which is about 10% of the volume. I put the screened material on a tray in the oven at 200 for about an hour and it gets rid of the moisture. I then put the cooled baked dolomite into sealed large freezer bags so they wont reabsorb too much moisiture. For what I do a batch weighing a pound or so lasts me a fair amount of time and takes about 10 minutes to do all the seiving. I have not convinced myself yet that the baking is really doing much good, but I know other people have indicated that it is a must do to get good results.

The mositure traps that come on the Paashe are not really that good. They are more dirt filters. I would always put a filter mositure trap on my airline out of the compressor. They are cheap at about $20 to $25 up here in Canada. I subdivide lines with a combo of a presure regulator followed by a mositure trap. On the line that I use for air abrasion I actully have a pressure regulator then a normal filter mositure trap and then a moisture trap that has a colour changing dessicant in it. Turns pink when you need to change the desicant.

[TOM BUCKLEY]

Thanks Tom,

Ill have to return the AECR unit as it hasnt even been delivered yet and I will order the kit here http://www.amazon.co...pd_sim_sbs_ac_5

Any reccomendations to source powdered limestone or dolomite.

Also this kit contains a moisture trap, will this suffice for one on my setup?

Will this powdered limestone suffice if I screen it before use http://www.amazon.co...28&sr=8-1-spell ?

Thanks

I get my dolomite from Paleo-Tools which is a distributor for Crystal-Mark. I think it was $12.00 for a couple of pounds + $12.00 for shipping. A little pricey but it comes with an average particle size of 44 microns so I don't have to sieve it. Isn't dolomite just a type of limestone?

I guess I have dry air.....or I just don't run my compressor enough, but I have no moisture problems. I just use the moisture trap that came with the Paasche and only drain my compressor's tank every few months and then ....only get e few drops of water.

Tom

[Malcolmt]

Interesting , if I run my compressor (Porter Cable 4 gallon round unit) for a day of working on fossils (it will kick on every few minutes for about 20 seconds set at 165 PSI) when actually being used I will generally get about an once to maybe even as much as two out the drain

[TOM BUCKLEY]

Interesting , if I run my compressor (Porter Cable 4 gallon round unit) for a day of working on fossils (it will kick on every few minutes for about 20 seconds set at 165 PSI) when actually being used I will generally get about an once to maybe even as much as two out the drain

Malcolm,

I think my lack of moisture is due 1) The size of my compressor. It's 6 hp, 33 gallon. So it just doesn't run enough to develop a significant amount of moisture. 2) I don't use my air abrasive system for more than a few minutes at a time, therefore putting a very small demand on the compressor.

Tom

[Malcolmt]

<p>Now thats a real compressor you've got there. When I'm prepping I blow a very small stream of air over the fossil to remove the material as I prep. I read an article somewhere on someone who had built the blower tool and I just copied the idea. Works real well prevents me from having to blow the fossil off to be able to see what I am doing. I do all my prep under an Olympus scope to which I have the homemade blower attached to the ring light. I have it just turned on enough to move the cleaned material out of the area I am working on. So my compressor kicks in every few minutes for about 20 seconds more frequently if I am using a scribe. I use the scribe (generally one of my AROs ) far more frequently than the air abrasion which I generally just use at the end for final clean up. Most of what I do is very old school using homemade carbide 1 mm scribes for the close up work. I use a diamond cut off blade on my dremel to shape them into both point and chisel shapes.

My understand about natural dolomite is that it is a form of limestone and is mostly calcium carbonate but can contain magnesium carbonate as well. There is chemically pure dolomite which is CaMg(CO3)2 and there is dolomitic limestone which is just a mixture of calcium carbonate and magnesium carbonate.

Because of the magnesium content dolomire is slightly harder than just pure cacium carbonate.

Edited December 10, 2011 by Malcolmt

[TOM BUCKLEY]

<p>Now thats a real compressor you've got there. When I'm prepping I blow a very small stream of air over the fossil to remove the material as I prep. I read an article somewhere on someone who had built the blower tool and I just copied the idea. Works real well prevents me from having to blow the fossil off to be able to see what I am doing. I do all my prep under an Olympus scope to which I have the homemade blower attached to the ring light. I have it just turned on enough to move the cleaned material out of the area I am working on. So my compressor kicks in every few minutes for about 20 seconds more frequently if I am using a scribe. I use the scribe (generally one of my AROs ) far more frequently than the air abrasion which I generally just use at the end for final clean up. Most of what I do is very old school using homemade carbide 1 mm scribes for the close up work. I use a diamond cut off blade on my dremel to shape them into both point and chisel shapes.

My understand about natural dolomite is that it is a form of limestone and is mostly calcium carbonate but can contain magnesium carbonate as well. There is chemically pure dolomite which is CaMg(CO3)2 and there is dolomitic limestone which is just a mixture of calcium carbonate and magnesium carbonate.

Because of the magnesium content dolomire is slightly harder than just pure cacium carbonate.

I've got the same problem. Sometimes the specimen is so covered with abrasive I have trouble seeing the surface. Could you describe your system in a little more detail? Thanks.

Tom

[Malcolmt]

I have tried to take some pictures here for you. It is quite simple I have a standard quick connect for the airline that goes to a simple brass screw valve that allows me to control the pressure. The airline that it is connected to is in a hub that is set at 35 PSI which I generally run to for my air abrasion units. When running I barely have the valve turned on, fully open it is way too stong and can peel fossil off the matrix. The nozzle at the end of the blower is just a 14 gage needle. I first made it with an 18 gage needle the same as I use for the Paashe units ( You can see one of the Paashe units on the side of the stand in the overview picture) but it was too restrictive; the 14 gage works much better. Without the needlle it just uses up too much air. I think it is standard 1/8th inch tube I am using rated to 100 PSI. From the valve it runs to the nozzle end. I took it appart to give you a picture. I then show it assembled attached to a goosneck that also has a battery operated LED light. (Light has 7 bulbs and lasts about 30 hours on 3 triple A) This can then be pointed exactly where I want it. I also have the ring light on the scope and two 150 Watt equivalent florecents that are pointed at the specimen. (You can never have too much light).

Most of what I do is with sharpened carbide scribes (made from 1 mm round carbide stock) or using one of the ARO airscribes. I do not use the blower when I am doing air abrasion. For that I have a shop vac that is hooked up to my dental abrasion unit that you can see as the blue unit in one of the pictures.

Edited December 11, 2011 by Malcolmt

[Auspex]

I have tried to take some pictures here for you. It is quite simple I have a standard quick connect for the airline that goes to a simple brass screw valve that allows me to control the pressure. The airline that it is connected to is in a hub that is set at 35 PCI which I generally run to for my air abrasion units. When running I barely have the valve turned on, fully open it is way too stong and can peel fossil off the matrix. The nozzle at the end of the blower is just a 14 gage needle. I first made it with an 18 gage needle the same as I use for the Paashe units ( You can see one of the Paashe units on the side of the stand in the overview picture) but it was too restrictive; the 14 gage works much better. Without the needlle it just uses up too much air. I think it is standard 1/8th inch tube I am using rated to 100 PSI. From the valve it runs to the nozzle end. I took it appart to give you a picture. I then show it assembled attached to a goosneck that also has a battery operated LED light. (Light has 7 bulbs and lasts about 30 hours on 3 triple A) This can then be pointed exactly where I want it. I also have the ring light on the scope and two 150 Watt equivalent florecents that are pointed at the specimen. (You can never have too much light).

Most of what I do is with sharpened carbide scribes (made from 1 mm round carbide stock) or using one of the ARO airscribes. I do not use the blower when I am doing air abrasion. For that I have a shop vac that is hooked up to my dental abrasion unit that you can see as the blue unit in one of the pictures.

We need to change your name to Macgyver...

Awesome setup; and no duct tape in sight!

[TOM BUCKLEY]

I have tried to take some pictures here for you. It is quite simple I have a standard quick connect for the airline that goes to a simple brass screw valve that allows me to control the pressure. The airline that it is connected to is in a hub that is set at 35 PSI which I generally run to for my air abrasion units. When running I barely have the valve turned on, fully open it is way too stong and can peel fossil off the matrix. The nozzle at the end of the blower is just a 14 gage needle. I first made it with an 18 gage needle the same as I use for the Paashe units ( You can see one of the Paashe units on the side of the stand in the overview picture) but it was too restrictive; the 14 gage works much better. Without the needlle it just uses up too much air. I think it is standard 1/8th inch tube I am using rated to 100 PSI. From the valve it runs to the nozzle end. I took it appart to give you a picture. I then show it assembled attached to a goosneck that also has a battery operated LED light. (Light has 7 bulbs and lasts about 30 hours on 3 triple A) This can then be pointed exactly where I want it. I also have the ring light on the scope and two 150 Watt equivalent florecents that are pointed at the specimen. (You can never have too much light).

Most of what I do is with sharpened carbide scribes (made from 1 mm round carbide stock) or using one of the ARO airscribes. I do not use the blower when I am doing air abrasion. For that I have a shop vac that is hooked up to my dental abrasion unit that you can see as the blue unit in one of the pictures.

Malcolm,

Thanks very much for sharing your system. I hope to duplicate it in the near future.

Tom

[squalicorax]

Hi everyone,

Thank you for all the advice on getting set up with an air abrader via Paasche.

This tool is pretty neat, I just picked up a Dewalt air compressor from the hardware store and purchased a 1/4inch male quick connector valve and I was ready to get prepping. I was working in a large tupperware container but I need to still build a containment system. Using the free Aluminum oxide they give you and testing it on some pyrite crystals I had and it seems to give them a nice sheen. Tried some junk matrix and noticed the AlO2 cuts through pretty quick through the mudstone or limestone matrix and the fossil. Luckly it was just a brachiopod .

anyways thanks, im working on a non shop vac material collection system at the moment and I will post pictures when it is all set up.

[squalicorax]

Here is my set up and I am beyond pleased

Thank you Tom and Malcolm for the exceptional tips

My total price for my set up was 165 dollars

I built my own blast cabinet and got a small compressor from Farm and Fleet.

The Passche AEC Kit - 56 bucks on amazon

Compressor is a standard 3 gallon one - 100$

Powdered 44 micron Dolomite from Swam Blast - 10$

Quick connector male piece from Home depot for 1$

Here are some pictures.

Edited January 22, 2012 by squalicorax

[Malcolmt]

Excellent!!!!!! Does not have to be pretty to work. Looking forward to seeing the first prep you post.....

[Wrangellian]

Sounds easy... tempting me to try and set up something similar once I get my shed cleared out of rock!

[Kehbe]

I finally picked up a blasting cabinet. I found it on craigslist! I had to drive almost to St. Joe to get it but I got it for $35.00. I need to replace the rubber gloves. It came with a light inside, a small ventilation fan and the gun you see in the pic. I tried putting smaller diameter nozzles in it but it restricted the syphon/abrasive pick-up power so I am going to have to get a proper gun. I added a flow control and pressure gauge, I already have a 5 gal. compressor and I may try and replace the plexiglas door. I thought it was a pretty good deal for $35.00

[Malcolmt]

Excellent deal, I have been tempted to get one from time to time but shipping up here to Canada is pretty much ridiculous. Cost me $100 to ship my dental blast unit which looks to be about 2/3 ds the size of this one.

Never pay retail !!!!!!!

And sometimes it just feels more like yours when you do a bit of a jury rig instead of buying the fancy stuff. Most of my stuff has a "McGuiver" of some type or other .........

[Taxman56]

the link is not going to a picture anymore