Testing blocks in the home shop

[GB SISSON]

Thanks all! This has been really informative and can save me a LOT of time, money and trouble hauling blocks over to the mainland. Of course when we are headed 'Over Town', i'm wearing my clean (work)clothes because we are usually going to see a doctor or some such.....and more often than not, we're in my wife's subaru wagon. Of course on the way home it's full of stuff from costco and sacks of bargain brand chicken feed for her hens. And the dog needs some room back there too. All that aside, I like doing things myself in MY shop.

[cas3]

Sounds like Jonny cash- " I put on my cleanest dirty shirt" ! , I resemble that remark. So, we are talking about pressure testing, but have gotten somewhat side tracked with preliminary cleaning. I've posted this before, but here's what I got out of one side of an old block. I bought the longest skinny screwdriver I could find, then taped a piece of copper tubing to the shop vac that fit in the block, then scraped and chipped and hacked with the screw driver and occasionally vacuumed it all out. ya gotta get all the way to the bottom, and its mushy down there so dig harder. Once done, I did Evaporust one side at a time.

[petehoovie]

Originally Posted by cas3

Sounds like Jonny cash- " I put on my cleanest dirty shirt" ! , I resemble that remark. So, we are talking about pressure testing, but have gotten somewhat side tracked with preliminary cleaning. I've posted this before, but here's what I got out of one side of an old block. I bought the longest skinny screwdriver I could find, then taped a piece of copper tubing to the shop vac that fit in the block, then scraped and chipped and hacked with the screw driver and occasionally vacuumed it all out. ya gotta get all the way to the bottom, and its mushy down there so dig harder. Once done, I did Evaporust one side at a time.

[GB SISSON]

Originally Posted by cas3

Sounds like Jonny cash- " I put on my cleanest dirty shirt" ! , I resemble that remark. So, we are talking about pressure testing, but have gotten somewhat side tracked with preliminary cleaning. I've posted this before, but here's what I got out of one side of an old block. I bought the longest skinny screwdriver I could find, then taped a piece of copper tubing to the shop vac that fit in the block, then scraped and chipped and hacked with the screw driver and occasionally vacuumed it all out. ya gotta get all the way to the bottom, and its mushy down there so dig harder. Once done, I did Evaporust one side at a time.

Wow! That's a load of crap you got outa there. I am really getting excited to test all these blocks. I did sneak ahead and watch a 5 minute video called 'what is magnafluxing?'. Way more straightforward than I would have thought. Anybody have an opinion on electro-magnet vs permanent magnet. Video says either one works and this guy likes his old permanent one. One thought comes to mind is I have always wanted to own a magnetic drill press. Would it do double duty as my block magnetizer?

[Tim Ayers]

Originally Posted by GB SISSON

Wow! That's a load of crap you got outa there. I am really getting excited to test all these blocks. I did sneak ahead and watch a 5 minute video called 'what is magnafluxing?'. Way more straightforward than I would have thought. Anybody have an opinion on electro-magnet vs permanent magnet. Video says either one works and this guy likes his old permanent one. One thought comes to mind is I have always wanted to own a magnetic drill press. Would it do double duty as my block magnetizer?

I recall someone selling an inexpensive kit for the home garage. I can't seem to find it with a Google search.

[cmbrucew]

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Wrap a welding cable around it 3 or 4 wraps and weld.


Bruce

[GB SISSON]

Originally Posted by Tim Ayers

I recall someone selling an inexpensive kit for the home garage. I can't seem to find it with a Google search.

I saw a guy using an aerosol spray device from Eastwood. Has a holder for 4 small vials. A cleaner, a prep, a red dye and lastly a chalky white spray that outlines a crack. Not magnaflux, but a very portable device a guy might wanna take to a swap meet or to the shed behind somebody's barn when following up on a craigslist ad.
P.S. If there's even a hint of banjo music, go back to your truck and grab that other device from your glove box.....

[slowforty]

I wonder if heating up a block would do any good. An Older relative, now gone, Used to heat up Flat head blocks on a wood stove before he welded up cracks . When he got a little to careless when doing a porting job. They were ready to weld up when he spit on them and it sizzled.

[GB SISSON]

Originally Posted by cmbrucew

Wrap a welding cable around it 3 or 4 wraps and weld.


Bruce

Bruce, are you saying that wrapping the welding cable around the cast iron block then welding on something will temporarilly magnetize the block, thus aligning the powder with a crack???? Like the block becomes the magnet? Maybe you were kidding, or maybe I missunderstood or maybe you are serious. I really don't know much about electricity and magnetism and in general, things I cannot see.

[cas3]

In the model T world, we wrap some 12 ga wire around a big bolt to make an electro magnet to recharge the magneto. Use 2-3 batterys in a series and zap one time. Short version from memory, but yes, I suppose if you wrapped cable around the block you would be making an electro magnet.

[tubman]

Sounds like it would work, but who has welder cables long enough?

I sure don't.

[sugarmaker]

Gary,
Did you discuss the spray crack finder. Two colors a red base and white top coat, and cracks show up? poor mans magnaflux? I used it on the 32 B block, which did have many cracks.
Regards,
Chris

[GB SISSON]

Chris, Yes that's the Eastwood kit that has the vials. Did it show up the cracks as advertised? In my youtube research I have seen some very powerful electro-magnets made by removing the primary coil from the innards of a microwave oven. Or was it the secondary coil?

[flatford8]

I think your on to it with the welder. A fabricator I know had to weld a large tank and somehow it got magnetized. He had to demagnetize (Degaussing) it. I think he wrapped the positive cable around the tank in one direction and the ground in the other direction. He was then able to weld on the tank. So, I would think wrapping one or both of the cables in the right direction may magnetize the block. Some type of store bought kit may be much easier.....Mark

[cas3]

If GB lived closer to me, we may be able to magnetize the block just by setting it on my steel table ! For some unknown reason over the last year or so the table has become a magnet. If you set down a tool, or nut and bolt when you pick it up again it has steel fuzzies all stuck to it. Very annoying if you are trying to do any clean work. I've not figured it out yet. Grinder snot ? alien invasion ? Any idea's ?

[GB SISSON]

Originally Posted by flatford8

I think your on to it with the welder. A fabricator I know had to weld a large tank and somehow it got magnetized. He had to demagnetize (Degaussing) it. I think he wrapped the positive cable around the tank in one direction and the ground in the other direction. He was then able to weld on the tank. So, I would think wrapping one or both of the cables in the right direction may magnetize the block. Some type of store bought kit may be much easier.....Mark

It would certainly be cheaper than 50' welding cables! From the video I saw, all that's needed is a magnet and some 14.00 powder and a modified turkey baster.. Seems the best magnet has 2 legs that straddle the bore and testing is done at 90 degree intervals. The poles have to be roughly at right angles across the crack. In other words, if the coil of the magnet is in line with a crack, it won't show up properly. Couple of questions:

Is iron a better core than steel?
How do we know how many wraps of wire are needed?
Do I need special wire with thin insulation like on a motor armature?
Is a 12 v car battery the right power source?

[GB SISSON]

I dropped off a new head gasket and water pump gasket at my buddy's fab shop so he could get the software in the cutting table computor. I mentioned I would need a price and also mentioned the out of stock speedway kit was about 250.00 with gauge and rubber gasketed bolts. His response was the labor is in the programming etc, then he can make as many parts as I want. I'm not soliciting orders here but let's just say the guy kinda grimmaced when I gave him the speedway 250.00 number. I have not heard from him and it's been 3 weeks at least. He seemed to think with that many head bolts, 1/4" plate should be fine. As much as I hate going to UPS or Post office and waiting in line (24 mile round trip).... But for yucks is anybody interested in a set of the plates? His machine 'drills' the bolt holes too. If it's too spendy in the end I will just use heads. And to revisit my magnet question, would garden varity electrical wire (as opposed to armature winding special wire) work ok? My research says a magnet in a horseshoe shape is the most powerful. PS We're going to the dump today... Our county dump includes a warehouse called 'the exchange' where folks drop of useable stuff they no longer need. Would romex house wire with the casing stripped off be an ok choice?

[Mart]

Take the wire to a metal recycler. Price for copper is sky high right now.

[cmbrucew]

Gary
Wrap your stinger wire around the block 3 times, and ground a big electrode Turn on welder and you have a magnetic field.
Bruce
Pacemakers beware!

[GB SISSON]

Originally Posted by cmbrucew

Gary
Wrap your stinger wire around the block 3 times, and ground a big electrode Turn on welder and you have a magnetic field.
Bruce
Pacemakers beware!

I have two welders a Hobart 175 mig and an ancient Miller AC with a 2 cyl onan. I'd have to get the miller fired up and listen to it while I test all these blocks. I think easier to just get or make a magnet. Ever since I exploded the 12 ply michelin 2' away from my ear last spring I have been having a hard time with LOUD. And I came across another pic of the haul that day and the mighty 7.3/ZF/4x4 F350.