Transmission Soda, Bead or Walnut Shell Blasting Options

[tdgray]

When I blasted my carbs, the were out of the car and taken apart. I would never blast carbs together, put them back on the engine and expect them to run.

Umm.. obviously... same as you would to the tranny as well... blast it... clean it up... change fluid... same diff.

[kconway]

Are the gaskets between case part lines vulnerable to blasting?

[Tom_T]

After blasting or cleaning - you may want to try a clear coat HT engine or exhaust paint like those here from VHT (or another paint/coatings mfgr.) to seal in the Magnesium alloy case material.

http://www.vhtpaint.com/flameproof.html
http://www.vhtpaint.com/engineenamel.html

They also have a magnesium metallic if your case is really badly stained into the metal.

In all cases - proper surface prep is a must to have adherence, & check each paint to make sure it's made to stick to the specific alloy on which your applying.

[Katmanken]

The circular logic that goes on here sometimes is amazing.

It's ok to use soda on a sealed case becase when you do, it destroys itself on contact into smaller particles.

Did you know sand does the exact same thing. If soda is ok, then so is sand because they do the exact same things.

Heck skip the soda blasting of the outside, just put a handfull of sand into the case and polish the inside too while it runs. It will get smaller.... (IMG:style_emoticons/default/blink.gif)

Why not use dry ice blasting? The particles would sublimate into Co2 gas.

[kconway]

I think the bottom line to this discussion is how does the media get inside? I've heard alot of folks say no way, but haven't heard a good explanation as to how the media gets inside if you take the proper precautions. I qualified my question with at least the common sense to completely cover the vent, where else is it vulnerable. If there was another path, my garage floor would be a huge puddle of tranny fluid.
Hey, I was dumb enough to rattle can it, I'm sure I can muster the stupidity to blast it. (IMG:style_emoticons/default/biggrin.gif)

[Katmanken]

It's pretty simple to explain.

Start yer compressor, pinch yer lips as tight together as you can, place an air nozzle up to yer lips, and pull the trigger.

I guarantee you that no matter how hard you pinch your lips together, at blast pressures the air will blow them apart. If there was sand being propelled by that pressure, your mouth would be full of grit.

Thats what the blast pressure will do to the O-rings and seals in the tranny.

[kconway]

It's pretty simple to explain.

Start yer compressor, pinch yer lips as tight together as you can, place an air nozzle up to yer lips, and pull the trigger.

I guarantee you that no matter how hard you pinch your lips together, at blast pressures the air will blow them apart. If there was sand being propelled by that pressure, your mouth would be full of grit.

Thats what the blast pressure will do to the O-rings and seals in the tranny.

AGAIN...the key is taking the right precautions. Why would I stick the air nozzle in my mouth if I didn't want sand to get in my mouth? Why would I aim the blast media at a rubber seal or O-ring, a vent or case part line? Why would I use sand? I'd love to have someone with practical experience regardless if it's foolish or not respond to this thread.

[Katmanken]

I'm just curious why you are even asking us?

If you have considered every issue and have all of the right precautions in place, we are wasting our time replying to your questions.

A lot of us have offered opinions that differ from yours, and I've even given you a solution that won't screw anything up and won't require taping.

Let me know how your decision works out for you.

Take care,

Ken (IMG:style_emoticons/default/popcorn[1].gif) (IMG:style_emoticons/default/popcorn[1].gif) (IMG:style_emoticons/default/popcorn[1].gif)

[Dr Evil]

Place your bets, place your bets (IMG:style_emoticons/default/rolleyes.gif)

You have a high likelihood of epic failure. If that is not a bother to you, proceed at your own peril.

But, what do I know? (IMG:style_emoticons/default/rolleyes.gif)

Mark and Zach had it correct in the first few posts.

[kconway]

I'm just curious why you are even asking us?

If you have considered every issue and have all of the right precautions in place, we are wasting our time replying to your questions.

A lot of us have offered opinions that differ from yours, and I've even given you a solution that won't screw anything up and won't require taping.

Let me know how your decision works out for you.

Take care,

Ken (IMG:style_emoticons/default/popcorn[1].gif) (IMG:style_emoticons/default/popcorn[1].gif) (IMG:style_emoticons/default/popcorn[1].gif)

Nevermind...

[Tom_T]

I think the bottom line to this discussion is how does the media get inside? I've heard alot of folks say no way, but haven't heard a good explanation as to how the media gets inside if you take the proper precautions. I qualified my question with at least the common sense to completely cover the vent, where else is it vulnerable. If there was another path, my garage floor would be a huge puddle of tranny fluid.
Hey, I was dumb enough to rattle can it, I'm sure I can muster the stupidity to blast it. (IMG:style_emoticons/default/biggrin.gif)

Kev - the good & the bad about soda & fine walnut media are that the fineness doesn't destroy the rubber & plastic lenses on a car when say you're blasting the body, but it is also fine enough to find its way under pressure into the damnedest places! It just gets by the tiniest of cracks or gaps, as well as being able to make the adhesive on tape fail, etc., etc. This is the bane of fine media blasting! (IMG:style_emoticons/default/dry.gif)

Any precautions which you take to close off all the gaps, vents, seals, etc. may or may not prevent any from getting inside a mechanical part such as a tranny. If it were a case prior to rebuilding, then you'd blast it, clean it & rebuild a clean case - but this is an operating tranny that we all presume you want to keep that way.

So I guess - proceed at your own peril with medial blasting, or else try some of the other suggested paint removal & clean-up methods here! ... it's up to Bud, because you're writing the checks on your 914! (IMG:style_emoticons/default/confused24.gif)

[McMark]

I'd love to have someone with practical experience regardless if it's foolish or not respond to this thread.

(IMG:style_emoticons/default/confused24.gif)



Blast your transmission already. (IMG:style_emoticons/default/rolleyes.gif)

[r_towle]

NO!
Forget the media you are using for a second...
Where is all the debris that is on the tranny going?

Never use an abrasive on a tranny....its just not sealed well enough to guarantee it wont get in or force something in.

When I clean a case, Its empty.

Rich

[kconway]

NO!
Forget the media you are using for a second...
Where is all the debris that is on the tranny going?

Never use an abrasive on a tranny....its just not sealed well enough to guarantee it wont get in or force something in.

When I clean a case, Its empty.

Rich

Look guys, don't make this a place where someone is afraid of asking questions. Plenty of you have responded with vague, NO NOT HERE type of responses without providing any real reasons. All I've been trying to understand is how the media might contaminate the transmission. I like to try to solve problems which is why I have been persistently asking for the "how". (IMG:style_emoticons/default/headbang.gif)

This has always been an open forum, a guy shouldn't get ridiculed or kicked in the teeth for challenging an opinion that's not backed up with some sort of reasoning.

I do appreciate your feedback, the sarcasm and ridicule; not so much. Apparently it's forbidden to ask for an explanation here so as I said a few posts back, nevermind.

I'm done, no need to provide any additional eyerolls, (IMG:style_emoticons/default/confused24.gif) looks. I'll leave the paint on.

Thanks, and to those I've wasted your time; I do appologize.
Kev

[r_towle]

Axle shaft oil seals will let debris in.
Rear speedo will let debris in.
Tranny vent will let debris in
Front main shaft oil seal will let debris in
Shifter console will let debris in.

Rich

[Eric_Shea]

I don't think Kevin deserves all of the $hit herein.

Hats off to Rich. It's a good list of probable problem areas.

[Katmanken]

Kevin,

Maybe I wasn't clear and you took it wrong. You wanted an answer on how blasting would allow the ingress of grit and I tried to give it to you in a graphic fashion.

The reason that I used it is I've done a lot of sandblasting, and the grit riccochets off the surfaces and goes everywhere. To clean up, you shove an air nozzle inside your clothes to remove an amazing amount of sand and particles. Your face is coated in grit around the goggles, and when you use the nozzle to clean the sweat adhered particles from your face and hair, you will find that your lips can't be kept closed. No matter how hard you try. In that case, a water mouth rinse and spit removes most of the grit.

The physics behind spreading your lips and spreading the seals/o-rings with air pressure is exactly the same. That is the point that I was trying to make and it came from blasting experience. And, somehow, the sand even managed to find it's way past my ear plugs and into my ears.

I have also used duct tape to mask and it does a pretty good job resisting the blast media. Sand bounces off, but the tape wears over time.

When the duct tape was peeled up, there were little channels of fine grit rammed under the tape and down any fold in the tape. These folds happen when the flat tape is applied to a non-flat surface. New tacky tape works much better at bouncing sand than a roll of old dried tape.

I hope that helps.

Ken