Air Scribes For Detail Work

[Jdeutsch]

When working soft matrix- always afraid of doing damage. Doing a lot by hand with a needle.

Can someone give an opinion on how they would go about cleaning the trilobite shown?

Is a fine air scribe good for this kind of work?

[Fossildude19]

I wouldn't use an air scribe for that work...

Either air abrasion, or,... a wire wheeled brush with a dremel / electric rotary tool would do the trick - that is the usual method of cleaning the U-dig trilos up.

Regards,

[Raggedy Man]

If you're referring to a pneumatic scribe like the Chicago Pneumatic Scribe or the paleo-tools micro jack I'd say no. For close work like that I've started using air abrasion. It's slow work, but it's better than obliterating the specimen with one wrong move. Air abrasion can also obliterate your piece as well, but there's more control through different media and technique. They're relatively cheap unlike the pneumatic scribes.

[jpc]

Raggedy Man... what air abrasive are you calling relatively cheap? I agree, air abrasive is the way to go for that last little skin of rock on Utah trilobites, and most fossils for that matter.

[Raggedy Man]

I use a master brush. It's used for glass etching, removing ink/paint from paper,and rust from bolts. It works very well on shale and sandstone. I have not had an opportunity to test it on harder matrix yet. It's gravity fed and operates around40-70 psi. It accepts a wide range of media. I hope this helps.

I paid about $45

Best regards,

Paul

Edited May 5, 2015 by Raggedy Man

[Fossildude19]

Raggedy Man... what air abrasive are you calling relatively cheap? I agree, air abrasive is the way to go for that last little skin of rock on Utah trilobites, and most fossils for that matter.

JP -

I use a Harbor Freight/Central Pneumatics air eraser that cost me about $25.00

Regards,

[ZiggieCie]

Harbor freight air abrader here too. Dolomite powder or baking soda. I picked up a 50 lb. bag of field, baseball soccer etc marking powder at a garage sale $2.00. It is powdered dolomite and works fine when dried.

[Raggedy Man]

Do you use the baking soda right out of the box or do you dry it further?

[jpc]

Thanks, guys.

[ZiggieCie]

I dry everything I use in the air abrader or they clog too easy for me. Don't use the aluminum oxide that comes with some air abraders on anything delicate, it is very abrasive.

[Jdeutsch]

What are you doing for dust control while working?

[Raggedy Man]

I made a blast box out of MDF and a piece of clear acrylic. The overall cost was about $17 total.

[Ptychodus04]

I use a jeweler's air abrasive unit. It was $120 but has a large pot, foot control and a decently long hose on the business end.

[jpc]

What are you doing for dust control while working?

I use a woodshop dust collector with the finer than normal bags.

http://www.amazon.com/AP400-Shopmaster-1-Horsepower-Vertical-Collector/dp/B00006K005

[Fossildude19]

I use a shopvac attached to the blast cabinet (another Harbor freight special ) with a hepa filter installed.

I don't do a ton of prepping, so although it is loud, it suits my purposes.

Regards,

[jpc]

Oh, and I forgot to mention that I have a home made chamber to do the work in. I do a lot of air abrasive work. I tried it with a shop vac and it drove me nuts very quickly. Very loud.

[rejd]

Some good information. I am going to order this unit to try out. http://www.harborfreight.com/air-eraseretching-kit-69277.html There is currently a 20% off coupon code you can use as well. Its 28047609.

[Raggedy Man]

What a great topic this has been! We need more preparation threads like this.

[ZiggieCie]

What are you doing for dust control while working?

I made a blasting box out of an old cooler chest and this very good water/dust filter (I, and you can make) attached to a small wet/dry shop vac.

http://www.instructables.com/id/Drywall-Sanding-Dust-CollectorSeperator/

This way I get no dust into the room or my lungs (not good). I have used a commercial water/dust filter for some work with drywall but needed a larger unit for the amount of dust generated with an abrasive unit.

Here is a link to the small dust collector. and photos of others for ideas.

http://www.sandkleen.com/products.htm Homedepot/Lowes may have them.

https://www.google.com/search?q=drywall+dust+collector&rlz=1C1SFXN_enUS498US498&espv=2&biw=1600&bih=799&tbm=isch&tbo=u&source=univ&sa=X&ei=1mFLVbO9LbLgsAT0zYDIBQ&ved=0CDYQsAQ

Ziggie

Ps. If you use a water filter and if you would want to empty it, do not pour the sludge in the bottom of the bucket down the drain, it could cement it shut, $$$$$

Edited May 7, 2015 by ZiggieCie

[Auspex]

...Ps. If you use a water filter and if you would want to empty it, do not pour the sludge in the bottom of the bucket down the drain, it could cement it shut, $$$$$

Should we even ask how you know this?

[Ptychodus04]

I dump my waste rock beside my foundation on the downhill side of the house. I figure it needs and help it can get!

[Ptychodus04]

Some good information. I am going to order this unit to try out. http://www.harborfreight.com/air-eraseretching-kit-69277.html There is currently a 20% off coupon code you can use as well. Its 28047609.

I had one of those as my first microabrasive set up. It worked well but I got really frustrated with having to constantly stop to refill the small media cup.

[rejd]

I had one of those as my first microabrasive set up. It worked well but I got really frustrated with having to constantly stop to refill the small media cup.

Thanks for the heads up. Never thought about that.

[ZiggieCie]

A might be helpful link.

http://www.thefossilforum.com/index.php?/topic/52819-how-do-i-modify-paasche-air-sandblaster-for-hyperdermic-needle/