WET SANDBLASTING A 914 |
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WET SANDBLASTING A 914 |
Curbandgutter |
Aug 10 2016, 04:45 PM
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#1
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Senior Member Group: Members Posts: 564 Joined: 8-March 13 From: Murrieta CA Member No.: 15,637 Region Association: Southern California |
Well I'm getting ready to wet sand blast (WSB) my project car and I wanted some input form those who have done it and or have some direct or indirect experience with it. I purchased a wet sand blasting kit from a company back east. I tried a sample piece and was thoroughly impressed. I was able to remove the paint down to bare metal on the underside floor in under 5 minutes. It was incredibly fast. The primer that I am using is an epoxy primer by SPI. I spoke with the manufacturer and they said to steer away from using a rust convertor as they can be very tricky to remove from seams. They also said to just blast it and spray it the next day. The flash rust will not be a problem. What has been your experience
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Tom_T |
Aug 10 2016, 04:54 PM
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#2
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TMI.... Group: Members Posts: 8,320 Joined: 19-March 09 From: Orange, CA Member No.: 10,181 Region Association: Southern California |
I know that the guy at my shop wont sandblast at all because the media is too aggressive, & can warp the panels.
As for waiting to the next day to spray the primer - especially with wet sand/media - since I've had flash rust over night when I wire wheeled small areas & thoust it would be okay overnight (I'm also in relatively dry SoCal). You might consider using soda or walnut shells or other less aggressive media for blasting. Hopefully Rick/Alien or some of the other body shop members will chime in here on your question. Good Luck! (IMG:style_emoticons/default/beerchug.gif) Tom /////// |
Curbandgutter |
Aug 10 2016, 05:01 PM
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#3
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Senior Member Group: Members Posts: 564 Joined: 8-March 13 From: Murrieta CA Member No.: 15,637 Region Association: Southern California |
I'm WET blasting therefore there shouldn't be any warping? Right?
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SirAndy |
Aug 10 2016, 06:29 PM
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#4
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Resident German Group: Admin Posts: 41,815 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
Don't do it! You'll have sand coming out of the cracks for years.
Don't ask me how i know, still makes me angry talking about it ... (IMG:style_emoticons/default/headbang.gif) 5 years (FIVE!) after the sandblasting: (IMG:style_emoticons/default/icon8.gif) (IMG:http://www.914world.com/bbs2/uploads/post-179-1151215349.jpg) |
Jeff Hail |
Aug 10 2016, 06:39 PM
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#5
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Senior Member Group: Members Posts: 1,141 Joined: 3-May 07 From: LA/ CA Member No.: 7,712 |
I'm old school BUT for a full strip "dustless blasting" is the new kid on the block
Its wicked fast, uses about 80% less media versus straight media blasting. The wet plasma helps everything along and flushes the debris away. Correct is does not generate heat, in fact it gets cooler a couple degrees below ambient which eliminates any fear of warping. I've seen glass beads used as media. Water will get everywhere so making sure the H20 has a place to exit is a must. Warm weather would be an advantage. The bare metal finish is interesting since the water buffers the media impact and you don't get a gigagazillion micro craters. I saw this demo'd on truck body parts both on aluminum and steel. On aluminum I would use it in a heart beat. I would do it on steel but I would still machine sand AND use a lite chemical metal prep. You can also learn from Andy the resident German that in some places duct tape may help sealing off areas you do not want media to get into. In the end you are going to have media in places including your ears that you thought it wouldn't get into. |
Vapor_locked |
Aug 10 2016, 07:11 PM
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#6
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Member Group: Members Posts: 74 Joined: 1-August 12 From: the middle of the time before Member No.: 14,746 Region Association: Upper MidWest |
I'd second & listen to what Jeff has said, and what Sir Andy has pointed out! Good luck with the project!
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charliew |
Aug 10 2016, 08:19 PM
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#7
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Advanced Member Group: Members Posts: 2,363 Joined: 31-July 07 From: Crawford, TX. Member No.: 7,958 |
I would use a rust converter especially if the color of the metal is still dark, but with a sponge to keep it out of the seams. Avoid any runs or sags and watch for little parts of the sponge hanging on the rough metal when you start painting. I spent about 4 months on a 42 ford jeep and it had so much converter on it we reblasted it and then I rewiped it with a thin coat of converter and primered it before I started wiping filler on it. The driver side and floor was pretty far gone. Epoxy non sanding primer then seam sealer then when it is ready another coat of epoxy non sanding primer thinned with the same brand single stage reducer ie: dt reducer to keep the orange peel down. Then I apply the sanding primer. I try to spread filler on the non sanding primer pretty quick like it was a coat of paint otherwise the primer will need to be roughed up and then you gotta watch for scratching through the primer. I use a lot of epoxy non sanding primer to avoid all the extra sanding. You can put the mixed paint in the refrigerator and even the cup off the gun If you gotta stop for awhile. You will need to watch the gun head and blow wash thinner through it if it has to set very long. I would also try not to blow the blasting material into cavities. Hope it turns out like you want it to.
Once a contractor asked me how did I like the job he did on my driveway and I said nothing turns out like I imagined it but it was ok. |
jcd914 |
Aug 10 2016, 09:48 PM
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#8
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Advanced Member Group: Members Posts: 2,081 Joined: 7-February 08 From: Sacramento, CA Member No.: 8,684 Region Association: Northern California |
Mark Whitesel (Mikey914/914Rubber) did this to one of his cars.
You can read his thread and watch the video he linked in. Mark's Stripper Thread Jim |
jmitro |
Aug 10 2016, 10:29 PM
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#9
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Senior Member Group: Members Posts: 713 Joined: 23-July 15 From: Oklahoma Member No.: 18,986 Region Association: None |
my car was media blasted (non WSB) for $1100 in my driveway. No panel warping that I'm aware of. It came out very clean, but there IS a lot of hidden media in the car like Andy described (not a big deal to me since it falls out as I rotate the rotisserie frequently).
As far as flash rust.....In my experience, I've left the bare chassis in my climate-controlled garage for two months with minimal rust since then.....except where my sweat gets on the bare metal. Ideally it would be nice to immediately primer the entire car, but I had too much grinding/welding left to do. I probably should have primered the areas that were finished (like the front trunk or hood) (IMG:http://www.914world.com/bbs2/uploads_offsite/i75.photobucket.com-18986-1470889782.1.jpg) |
scotty b |
Aug 11 2016, 06:46 AM
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#10
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rust free you say ? Group: Members Posts: 16,375 Joined: 7-January 05 From: richmond, Va. Member No.: 3,419 Region Association: None |
I own the wet system. ( Dustless blasting ) I have used it on a couple different cars. The main problems are :
The sand PACKS into the corners and crevices. You will have to dig it out with a screwdrivers or something similar. In the time it takes to get the blasting done, rinse it off with the HOLDTITE and then clean out the crevices and rinse them, the flash rusting has already started. High humidity makes the whole system uselss as fas as the rust prevention goes. Here in Va where we get jungle like humidity, I have the panels starting to flash rust almost immediately, despite putting 2-3x the recommended amount of HOLDTITE in the mix, and the rinse Despite what Tom T says about sandblasting in general, this setup WILL NOT warp panels. I have tried. When I first unboxed it I held the nozzle 1" off the center of a 914 trunk lid for well over a minute and it did NOTHING to damage the metal It's a great system for the outsides, but IMHO it plain sucks in enough ways that I almost regret buying it |
VaccaRabite |
Aug 11 2016, 11:32 AM
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#11
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En Garde! Group: Admin Posts: 13,553 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
High humidity makes the whole system uselss as fas as the rust prevention goes. Here in Va where we get jungle like humidity, I have the panels starting to flash rust almost immediately, despite putting 2-3x the recommended amount of HOLDTITE in the mix, and the rinse This would be the case for any blasting though, right? Blasting stuff clean in PA on a humid day you could see flash rust forming before I was even done clearing the pedal cluster (using aluminum oxide from a bucket blaster). I know when I was painting my 914, I tired to do all the body work pre-paint during the winter to control flash rusting (and this was with mechanical and chemical stripping). Humidity sucks ass. Zach |
mbseto |
Aug 11 2016, 12:19 PM
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#12
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Senior Member Group: Members Posts: 1,257 Joined: 6-August 14 From: Cincy Member No.: 17,743 Region Association: North East States |
Need a nitrogen atmosphere paint booth.
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Jeff Hail |
Aug 11 2016, 12:57 PM
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#13
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Senior Member Group: Members Posts: 1,141 Joined: 3-May 07 From: LA/ CA Member No.: 7,712 |
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mepstein |
Aug 11 2016, 01:24 PM
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#14
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914-6 GT in waiting Group: Members Posts: 19,516 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region |
I own the wet system. ( Dustless blasting ) I have used it on a couple different cars. The main problems are : The sand PACKS into the corners and crevices. You will have to dig it out with a screwdrivers or something similar. In the time it takes to get the blasting done, rinse it off with the HOLDTITE and then clean out the crevices and rinse them, the flash rusting has already started. High humidity makes the whole system uselss as fas as the rust prevention goes. Here in Va where we get jungle like humidity, I have the panels starting to flash rust almost immediately, despite putting 2-3x the recommended amount of HOLDTITE in the mix, and the rinse Despite what Tom T says about sandblasting in general, this setup WILL NOT warp panels. I have tried. When I first unboxed it I held the nozzle 1" off the center of a 914 trunk lid for well over a minute and it did NOTHING to damage the metal It's a great system for the outsides, but IMHO it plain sucks in enough ways that I almost regret buying it The shop where I work bought one before I came on. Same experience as scotty b. I think it's sitting in a box, in a corner. |
Vysoc |
Aug 11 2016, 01:38 PM
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#15
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Vysoc Group: Members Posts: 588 Joined: 27-August 09 From: Young Harris, Georgia Member No.: 10,737 Region Association: South East States |
I agree humidity is a monster, come to Florida its so humid it rains every afternoon between 1:00 and 5:00!
Now the fun two months August & September putrid heat (IMG:style_emoticons/default/barf.gif) ! Vysoc (IMG:style_emoticons/default/flag.gif) |
worn |
Aug 11 2016, 02:44 PM
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#16
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can't remember Group: Members Posts: 3,288 Joined: 3-June 11 From: Madison, WI Member No.: 13,152 Region Association: Upper MidWest |
Need a nitrogen atmosphere paint booth. Not really. Nitrogen does not carry moisture. You need atmosphere to bind water or solvent molecules to carry them away. But nitrogen does not easily create rust, which would be nice. The time when the sand from wherever becomes most apparent is when the spray gun mixes it out of the crevices and straight into the paint. Not fun at all. |
Curbandgutter |
Aug 11 2016, 06:47 PM
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#17
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Senior Member Group: Members Posts: 564 Joined: 8-March 13 From: Murrieta CA Member No.: 15,637 Region Association: Southern California |
Thanks guys. After talking to paint manufacturer, I'm going for it. Will strip with water and sand, have rotisserie so will spin often to get sand out of hidden areas, will mask off tubes, etc. We will see how it turns out. I'll post video as well. By the way this will also be in my build thread "V8 914 speedster build"
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914forme |
Aug 11 2016, 07:30 PM
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#18
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Times a wastin', get wrenchin'! Group: Members Posts: 3,896 Joined: 24-July 04 From: Dayton, Ohio Member No.: 2,388 Region Association: None |
(IMG:style_emoticons/default/popcorn[1].gif) good luck
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mbseto |
Aug 12 2016, 08:14 AM
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#19
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Senior Member Group: Members Posts: 1,257 Joined: 6-August 14 From: Cincy Member No.: 17,743 Region Association: North East States |
Need a nitrogen atmosphere paint booth. Not really. Nitrogen does not carry moisture. You need atmosphere to bind water or solvent molecules to carry them away. But nitrogen does not easily create rust, which would be nice. The time when the sand from wherever becomes most apparent is when the spray gun mixes it out of the crevices and straight into the paint. Not fun at all. Exactly- no oxygen, no rust. My comment was a a little tongue in cheek, but it would be interesting to try it... |
Mark Henry |
Aug 12 2016, 09:15 AM
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#20
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
Actually this looks interesting and you can get cheap ones now. Not pro models, but it may be all you need for a few jobs. You could use it to augment regular blasting and stripping, get all the heavy rust off, then sand and dry blast off any flash.
The big thing would be prep, blocking all holes to keep the sand out. |
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