Sandblasting

[SwtCraigMachine]

So, I have an old GT frame lying around that I want to use as a base for a project bike (and so it begins...). Unfortunately, the old paintwork is looking pretty knackered at this stage. I want to investigate the possibility of sandblasting it to a bare metal.

 

Has anyone tried this on an old frame before? With any success?

 

Does anyone know of a place in Cape Town that would do it for me (for a reasonable or non-existant price)?

[DirtyFrank]

So, I have an old GT frame lying around that I want to use as a base for a project bike (and so it begins...). Unfortunately, the old paintwork is looking pretty knackered at this stage. I want to investigate the possibility of sandblasting it to a bare metal.

 

Has anyone tried this on an old frame before? With any success?

 

Does anyone know of a place in Cape Town that would do it for me (for a reasonable or non-existant price)?

 

I think you`d be better off by using a quality water based paint stripper applied with a brush. I`d be concerned about sandblasting as this always leaves a slightly pitted surface.

[Wayne Potgieter]

I think you`d be better off by using a quality water based paint stripper applied with a brush. I`d be concerned about sandblasting as this always leaves a slightly pitted surface.

 

+1

[udxcob]

I had a frame sandblasted and it came out awesome, just go to the guys who do windows, they use fine grit

[EigerSA]

it totally depends on the sandblaster medium they use. as mentioned above, can come back very pitted. maybe phone some bike shops in the area and ask if they can recommend someone

[King_Crispy]

Taking into consideration that the frame could be weakened by them doing a *** job...

[Grebel]

Sandblasting is a sacrificial process meaning that in the wrong hands you could potentially kiss your frame goodbye. For the purposes of painting rather just rub it down, prime the bare metal and respray. If you want to polish it,rather use paintstripper and bucketloads of elbow grease.

[UvRooyen]

I would just sand it down with 400 grid water paper and lots of Water. Did a kids cycle last week and it was fairly fast.

[V12man]

Find someone who can soda blast in CT (specialist sandblasters often have this kit) - this will not do any damage to the metal, except remove rust and paint.

 

You can use a fine grit and a lower pressure in a sandblaster but badly done it will etch away any brass braising you might have on that frame (typical on older frames with lugs) - if it's a tig welded frame you should not have problems.

 

I have done both, and soda blasting is the best low risk route, but more expensive and harder to find someone who has the kit (but not impossible)

 

Once sandblasted/soda blasted, you need to be quick to apply primer or rust preventative coating, or it will begin to rust VERY quickly.

[Ed-Zulu]

Find someone who can soda blast in CT (specialist sandblasters often have this kit) - this will not do any damage to the metal, except remove rust and paint.

 

You can use a fine grit and a lower pressure in a sandblaster but badly done it will etch away any brass braising you might have on that frame (typical on older frames with lugs) - if it's a tig welded frame you should not have problems.

 

I have done both, and soda blasting is the best low risk route, but more expensive and harder to find someone who has the kit (but not impossible)

 

Once sandblasted/soda blasted, you need to be quick to apply primer or rust preventative coating, or it will begin to rust VERY quickly.

This advice is correct...had my frame repainted, it was glass blasted to protect the alu frame...sandblasting will be too rough on the metal

[JTK]

Risking asking a stupid question. SWTCraigMachine, did you get sorted with the blasting in Cpt. Wanting to do an old Anthem frame for my son. Factory powdercoat chipped all over the place . An old Anthem team frame so I want to keep the colours and have decals made to replace those that will be lost. Anyone have a call on a place that will do the decals in CPT?

[DJ84]

Im in industrial sandblasting and at this level you wont have a frame left.

Just remember that if you do sandblast use the finest gritt as with the window sandblasters.

 

Also you will need to apply a primer asap as corrosion at the coast starts taking place at a rapid pace.

[TiBones]

Someone on the hub used a home compressor and a few bags of soda ash from the local swimming pool shop. Ahhh but the old memory fails me sometimes

[JTK]

I fully understand the staying away from sand as blasting media. It is way to agressive. But tried phoning a "bigish" bike shop close by and asked about contacts for medai balsting and was told. "dunno, also looking for someone" and thought maybe I will try my luck here... I would like to find the right place first rather than on my 3rd frame

 

I think the powder coating is less of an issue. was quoted around R250 for a frame which seems reasonable...

[divernick]

I used a home compressor and some "Alkali Up", basically bicarbonate of soda.

 

It works well and doesn't damage the frame but it takes ages and loads of medium.

 

Trust me, use paint stripper like Durastrip and a paintbrush. Brush it on thick, wait 10 minutes and use a high pressure hose to spray it off.

Then use 320, then 600, then 800, then 1000, then 1200 grit water paper.

 

Stripping will take about 2-3 hours and sanding about 5.

[JTK]

Thanks Divernick. sounds like it will take a looooong time I would pay a good blaster a few bob to do it, if I can find him. I have worked with painstripper before. Hate the stuff. Almost lost an eye.