Badger Mini Abrasive Gun

[Ramon WilsonParticipant @ramonwilson3]

Hi,

As I’m approaching the finishing ops on a couple of crankcases I was wondering if anyone has any experience of using the small Badger ‘sand blaster’.

 

I am particularly thinking of using one to create a uniform surface finish on aluminium. Any info on it’s suitability (or not) for  this or similar applications would be appreciated.

 

Or is there something better – but for not much more cost!

 

Thanks – Ramon

[Ramon WilsonParticipant @ramonwilson3]

[CirclipParticipant @circlip]

Whatever you use Ramon, DO IT OUTSIDE, grit gets EVERYWHERE.

 

    Regards  Ian.

[Engine BuilderParticipant @enginebuilder]

I have one of these Ramon but have not found it very succesful. It covers  a very small area

and only gives a very fine surface finish. Maybe I am doing something wrong. I would be pleased to hear if anyone gets better results.l. I have tried at the recomended psi and also at greater pressures but was dissapointed with the results.

David

[BazParticipant @baz89810]

I also have one, about as much use as a chocolate teapot. Eventually bought one of the Machinery Mart benchtop ones, needs a bit of work doing to it to stop grit coming out in a fine mist everywhere and also a big compressor but at least it works, and yes DO IT OUTSIDE

regards Baz

[Ramon WilsonParticipant @ramonwilson3]

Thanks guys, I had a feeling that might be the response so it looks like that’s a non starter.

 

I notice there are others available – certainly more substantial, some even cheaper than the Badger, but they look like they might be a bit over kill for what I want to do —-

 

I only want to provide a uniform matt finish on the ‘cast’ area.

 

I was intending rigging something up so that  it could be done inside one of those big ‘cheap-shop’ clear polyboxes to contain the dust but yes – I would still do it outside.

 

Thanks for your input so far – any other ideas appreciated 

 

Just a thought has anyone designed one to be made at home  eg MEW?

 

Regards – Ramon

 

 

 

[Flying FiferParticipant @flyingfifer]

Hi Ramon

 

Ian Bradley (Duplex) designed one in ME Vol 140 issue 3488 part 1 starts on page 437 & then issue 3489 Part 2 page 502. I can let you have copies if you want.

Those crankcases look very similar to the old ED 246 or would they be the 5cc Miles.

 

regards Alan

 

[Ramon WilsonParticipant @ramonwilson3]

Hi Alan

Thanks for the info and kind offer. Sending PM

 

The cases are based on the ED 2.46 an early ‘favourite’ engine. I thought it would be a good basis for a scaled up – 5cc – version.

 

Its early days yet, the pic was taken yesterday so that’s current state of play. Fettling around the case with a dremel and rotary file is quite time consuming!

 

Thanks again – Ramon

[mgjParticipant @mgj]

I may well be wrong on this, but surely that fine matt finish on ali is vapour blasting?

 

Something in my decaying memory says so. 

 

Shot and sandblasting is more aggressive and is a pre-painting treatment after degreasing?

[CirclipParticipant @circlip]

OK, substitute shot and sand with glass beads, but STILL do it outside Ramon, and yes, the “Racer” was THE engine, a real Tiger.

 

  If you’ve used 6082 for the case, it’s GOT to be better than the **** that ED used for ALL versions of the originals. We were however not as affluent in those days.

 

  Regards  Ian.

[Ramon WilsonParticipant @ramonwilson3]

Ok guys, thanks as always for your interest.

 

Firstly I do have access to a grit and bead blaster. It belongs to a friend who will let me use it. It’s a bit of a trek so thought it would be nice to be a bit more independant and be able to do it when wanted.

 

Using his though this is what I have achieved before – this was a very well used (read caked with carbon)  OS35MaxS  totally rebuilt for aerobatics. Yes it has been well used since!

The finish is very fine to the touch but not as fine Meyrick, as vapour honing. It was done using glass beads.

Though not technically correct for an ED Racer – the originals had magnesium crankcases with a black protective finish –  the later MK4s had a shiny die cast silver finish – this finish would be nice to be able to achieve at home.

 

Not sure what the grade of ally is – I visited my last place of work a week or so back and was given it from a bar end. Machines very nice though both on the lathe and mill – probably HE30

 

Something in my fading memory bank tells me that something we (jobbing shop)  used to make for the blow moulding industry went off for vapour honing. That’s a long time ago and simply can’t think of what it was though – would I be right in thinking that vapour honing will not disguise very small scratch marks?

 

Thanks again – Ramon

 

[mgjParticipant @mgj]

Well that glass bead finish looks very good? I think I’m getting mixed up between glass beads and vapour.

Edited By meyrick griffith-jones on 20/02/2010 16:36:57

[Ian S CParticipant @iansc]

In my aircraft engineering days, I was in engine overhaul, and we used (I think) crushed wallnut shell for blasting pistons, cylinder heads etc,. Here glass grit is cheaper than sand (they make the glass out of sand!)I believe that plastic bead is available here and gives a nice finnish. Ian S C

[CirclipParticipant @circlip]

Shot Blasting, generic term like all vacs are Hoovers, and although a different media and applicator is used, Grit, sand, bead and vapour fall into the same classification. Initially coarser grade were used to strip and clean the metal surfaces, but then a “Sealing” operation using metal or glass beads closed the surface the former had cut open.

 

  Another problem not appreciated is the cross contamination by using “Used” blasting media. Stainless Steel and Alumininininium “Rust” quite well if you’ve done a bit of mild steel first.

 

I think the aircraft industry picked up on the walnut shells as that was the developed method for removing the crud from airfield marker light glass covers in situ rather than strip and scrub.

 

 

 

   Not going to have a go at anodising Ramon??

 

   Regards  Ian.

 

 Missed the bit about “Grit”, Grits and sand have sharp corners wheras glass beads are exactly that and impart a “Peening” opeation.

Edited By Circlip on 21/02/2010 12:05:47

Edited By Circlip on 21/02/2010 12:06:16

Edited By Circlip on 21/02/2010 12:08:35

[V8EngParticipant @v8eng]

As a general comment:

The new Machine Mart catalogue came yesterday, blasting equipment and powder / beads are all in there.

[Ramon WilsonParticipant @ramonwilson3]

I have heard of crushed walnut being used in mechanical deburers and I see on a certain TV programme that it’s used to strip paint off cars without damaging the metal.

 

I have used my friends kit on several occasions to resurect really badly (carbon) corroded engines – the glass beads do an excellent job for that but I would also like to use something coarser at some stage to simulate a ‘sand cast’  finish as Jens has done on his ‘Alpha’.

 

I’m now close to needing to put a finish on the cases before the final ops so I shall get over to Lee’s and use it for this job. If the I/C front  develops which I feel it will then I will do something about getting equipped at home.

 

Anodising Ian? You have a sixth sense!

I am hoping to do this to the cylinder heads etc. This will be a first so was intending to post on his closer to the event. I have some good information from Strictly I/C and I see there’s a good piece on it on the MEN site. Perhaps more on this subject later?

 

Thanks for the constant input – much appreciated

 

Regards – Ramon

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