Repairin aluminum crankcase

Don't really know the answer but sometimes the effort in a repair and the result just isn't worth it compared to the alternative...this might be one of those times.

I'd donate the old one here for parts but it's not the right one...too small so wouldn't help.

If the rest of your shop looks like that you could open it on weekends and compete with Owls Head for tourists.

I can hear the South Bend downstairs whining that I'm behind on its restoration.

-jsw

300-350 degrees will bake most of the oil out. You will want to solvent wash, bake, solvent wash then bake again to get the most oil out. Then scrub it to get the crud off before welding. 4043 rod/wire will do the job. Check around the broken out area for other cracks.

Many years ago I TIG welded a spot, that was missing a small chunk, on an Aluminum side cover on a Harley for a biker friend. I used a std Al rod, whatever that was. He had cleaned it up before he brought it over. Apparently he did a good job as I never had any complaints. IIRC he mentioned something about boiling it in acetone. How about maybe finding someone who has a vapor de-greaser or maybe a steam cleaner? If it's not in a critical place maybe you could make a cover plate and just bolt it on using a gasket to prevent leaks.

My thanks to everyone for your advice and information . The welding point has been rendered moot , I found a starter-side case half for 75 bucks and bought it ... along with a gasket set and a used con rod . I'm negotiating with a guy for a crank , if I get that it will replace all the parts that are broken . The pistons/bores are right at the wear limit , so I'll re-use those and give the cylinders a light hone to reseat the rings . Might see if I can knurl the pistons lightly to tighten things up just a smidgen . Looks like I'll be able to bring this repair project in right at the self-imposed budget .

You still might want to try welding up the old one for a bit of education/practice. No better way to try stuff out like that...

Had a break in the heat & humidity here yesterday. Managed to get a bracket welded back on my neighbor's old sickle mower. Nothing special,

1/8 inch 6013 stick after some serious grinding off the broken weld. Was going to use one of my 4.5 inch grinders until I looked it over again... Dug out my 9 inch and even using that one it took 5-10 minutes to make the old, broken weld disappear. That grinder makes piss poor tacks disappear too right quick too...

Was getting the hang of it again (stick welding) just before I was done ;-)

Count on it !

Update - the wife said "why not go ahead and replace everything you need to " so I looked for a set of pistons ... be sittin' when you price that stuff , it's all discontinued . I did find a standard piston for 142 bucks per with rings , but standard size only . Soooo , I'll be doing a light knurl on the thrust faces to tighten up a little (less is better , you're reducing the wear surface area when you do that) and installing new rings after a light honing . That might get another 15 years out of it ... it's already 33 years old .

You got me checking on parts for the B&S 18HP opposed twin in my ~1988 tractor.

The local hardware store had a new starter pinion for it.

-jsw

I would solvent wash until it seems clean, then maybe try a different solvent and wash again. I would start with paint thinner. Cheaper than any other solvent. and then try a little carb cleaner , or brake clean, or Acetone, or Trich,

The ornage based grease removers do not evaporate quickly so might be good to try that and then wait for some hours before solvent washing again.

I would not bake it between solvent cleanings. I could be wrong, but I think baking drives off all the lighter oils and makes it harder to wash out what is left.

My opinion is worth every bit of what you paid for it.

Dan

Sounds like my worst nightmare. But you're welcome to stop by on your way to Owls Head.

At least with the SB you can see or hear most anything that's likely to need attention.

Sounds like my TV. A 32 inch LG lcd tv. The picture went to hell and I am pretty sure it is the T con board. New T con board from LG , a mere $763.xx

A new 32 inch Samsung was $218. off ebay.

Dan

Most of it. The trade school apes broke off the oil fittings on the apron so the bushings on the gear that takes carriage drive from the leadscrew groove are badly worn. I replaced the external tubes with brake line tubing and new Gits oilers and found a NOS set of half nuts but haven't redone the power feed yet since I like the sensitive feel of feeding the carriage with the handwheel.

The worst damage they did besides never oiling it was using the tailstock spindle as an anvil horn. They don't appear to have used it as a lathe very much and the bed and spindle are good.

I stopped lusting for an HLV-H to replace it after reading this:

-jsw

I wouldn't quibble with most of what he says. Turning between centers on an HLV-H (and my Feeler) is a pain due to the lack of wings on the saddle. You have to really think ahead when setting up if you need to turn to the end of the work that's in the tailstock center. I have a VFD on mine, so low spindle speeds are possible, but that doesn't help with heavy cuts. He's right, it isn't to hard to stall the motor. On the other hand, the Feeler will turn true within a few tenths over 6 inches or more with a little care. And it didn't cost me any more than a SB in similar condition might have - $1500.

I wasn't allowed to touch the HLV-H in Mitre's main machine shop that was making laser optical parts for me. I cut the prototypes from aluminum at home to convince the electrical engineers that I could handle that part the task as well as the electronic tech work, and to become better at instrument making. The HLV-H did a noticeably smoother and more accurate job on stainless than I could with aluminum, though I was improving as I found, adapted to or repaired the quirks of my worn lathe. Also they had better 5C collets than my mostly second-hand collection.

Before assigning me the small model shop they surplussed its long bed

13" South Bend to make space for several other small machine tools rescued from closed labs all over the complex, a bad omen for my own future there. One that seemed promising to me if it had been built more carefully was the Enco 100-5100 version of this:

It's a modernized equivalent to my Clausing 8525 with an R8 spindle and the same compact size and moderate weight to fit in a home basement. Unfortunately the smaller parts like the graduated dials were too crudely made to use without cleanup.

For small parts like Variac brush holdes and working to scribed lines taken from the broken original I prefer the Clausing to a Bridgeport because I can easily reach the handles while watching the cut through a magnifier, and can pull the drive belt to start a lightly chucked tap straight.

Not that I'd turn down a Bridgeport if a nice one wandered by. I literally tripped over one down the street that had been disassembled and put beside the road for trash.

-jsw

Thanks, that looks like a nice catch for a hobbyist much closer to you. New England doesn't lack for machine tool "projects".

My 50-year-old American iron is nearly perfect for the small stuff I make one piece at a time. When new and unworn they would have been ideal for a 1960's model shop or inventor. Both have paid for themselves making proof-of-concept (NOT flight) hardware for space programs.

-jsw

A Clausing 8525.

They are a little smaller in capacity than an RF-31 mill-drill, and a lot nicer to operate.

-jsw

For difficult angular reaches a 40-position Multifix toolpost combines the precise repeatability of an Aloris with the rotational flexibility of a lantern toolpost. I latch the toolholder with the slot facing toward me to hold it steady while arranging and clamping a bit that needs fiddly packing pieces.

"You don't see them very often over here (usually on a nice Hardinge HLV-H when you do) but they're more common in Europe."

-jsw

Even I might have sprung for that one if it had been there when I visited. I might have found room for it. Nothing larger, though.

I liked the Dorians on Segway's CNC and manual lathes. I think the Multifix is a good solution for hand-ground HSS tooling whose angles aren't as well controlled as brazed and insert carbide. It might allow positioning the bit closer toward the Feeler's tailstock.

I don't extend the non-original tailstock spindle on my lathe any further than necessary when trying to turn accurately between centers and the Multifix at an angle on the right side of the post with a bent Armstrong holder allows the bit to face the RH end of the work, using a cut-away dead center.

The reason I use HSS is that carbide chips too easily on my worn machine, though I haven't tried it since I surface-ground the uneven compound base wear that prevented close gib adjustment. I made an expedition to find better small boring tools after having problems and came home with this:

I don't care that the coolant hole is clogged solid with chips.

What grade of carbide inserts should I buy for it to cut 303 stainless and moderately hard steel such as 4142 Prehard and Grade 8 bolts?

-jsw