Todays Project - What did you do today?

[TomG]

Days of practice and a $3500 inverter TIG welder.

[Roadracer_Al]

I've been welding aluminum on a hobby level for about 20 years.  I think what that actually means is that I've had about 6 months of experience 40 times over.  

RE: inverter, yes, I'd love to get one. My wife & I moved to Oakland from Maryland 6 years ago -- that would have been the perfect time to sell the trusty old Lincoln SquareWave 175 and buy a newer solid-state machine.... instead, I dragged that heavy lump out here.

RE: casting, yes, that would be a great project. I did some casting with lead when I was a kid, and I understand the process. I actually have a fairly challenging pattern-making project which I'd like to tackle: my '69 Yamaha DT250 is totally stock, and I'd like to cast a copy of a GYT or WebCo performance head for it. It's an air-cooled 2-stroke, the performance head is 2x heavier, with much bigger fins for better cooling than the stock head.

[dallen]

(04-09-2015, 12:37 AM)Roadracer_Al Wrote: RE: casting, yes, that would be a great project.  I did some casting with lead when I was a kid, and I understand the process.  I actually have a fairly challenging pattern-making project which I'd like to tackle: my '69 Yamaha DT250 is totally stock, and I'd like to cast a copy of a GYT or WebCo performance head for it.  It's an air-cooled 2-stroke, the performance head is 2x heavier, with much bigger fins for better cooling than the stock head.

if you have one to copy the ideal way would be to make a silicon rubber mold of it then make a wax cast from that then do an investment and burn the wax out of the investment.

next up easiest way would be to use cnc and make a wax pattern then do the silicon rubber mold.

hardest way is to make a wooden pattern which would probably have to be a multi part pattern (more than two pieces). Hardest of anyway that you do it would be the core boxes, but with an original you could cast the air passages and such in rubber then make core castings from them.

Anyway you look at it, its not an easy project, but then again others have done harder projects.

DA

[awemawson]

Hey it's a Sunbeam Alpine - they were a laughing stock when they came out, is it worth making a casting !!!!

[Roadracer_Al]

Yeah, they weren't fast with the 4-cylinder engine, and I'm sure being featured on Get Smart didn't help their reputation at all.

The suspension was pretty modest, too. They handled OK under normal circumstances, but poorly when pushed. IIRC, they had woefully inadequate roll bars from the factory.

But, I've always loved their looks. I'm slightly envious. I admit, if it were my car, I'd have done either a Tiger clone or put a SR20DET in it.

Regarding the cylinder head, no core box necessary since it's a 2-stroke, all the porting is in the cylinder. The fins are challenging, but it's a simple cope & drag job. I'll probably make a wooden pattern and sand cast it. My idea on the wood pattern is to saw "fin stock" strips on the table saw, then glue up an over-sized stack of them, then use the belt sander to bring it to size & shape, and apply fillets & details such as bolt bosses with Bondo.

[dallen]

sounds like you got a handle on it, the wood will have to be super smooth for the pattern to pull out but its doable.

DA

[dallen]

been messing with a little 22 magnum rifle I'm putting together for the shop monster to shoot snakes with.



The Wood that I'm using for the stock was gifted to me from a forum member. Looks like its going to work out just fine crack and all.
DA

[PixMan]

Altered the long steel shank of a Walter Screw-Fit adapted B3230.T18.20-26.Z1 precision boring head. The boring head screws onto the tapered, hardened steel shank. The OD of the boring head is 19mm (3/4"), and it's made to bore from 20mm (0.787") up to 26mm (1.0236") using a CCGT050204 (CCGT1.81.51) insert.

The "business end" of the steel shank where the boring head mounts comes down to a little below that 19mm, but I stopped at just a hair over 19mm when I turned it. It was really HARD steel! I think over 55Rc (560HBn) and may have actually been up to perhaps 62Rc. Fortunately I have some Valenite grade 9605 TiAlN coated inserts capable of turning hard steels, no problem. Normally that might be in the range where you go to CBN inserts which I also have, but I prefer using carbide inserts with chip control.

The customer of mine (yeah, a pay job for a change) said the shank cost him "only" $144, so if I screwed it up it wouldn't be a big deal. He needed to reach into a hole by about 3" (76mm), but at an extreme angle so he needed 5-1/2" clear. From there out to about where the original taper started it figured out to be about a 14.2º angle so I used the compound slide at that angle to make the new cone shape. Glad it came out good with no mishaps, because although the steel shank is relatively cheap, that boring head lists for $1,174.00. Ouch. I gotta tell you though, if you ever come across a deal on one those B3230 boring heads are the cat's meow. So smooth!

[EdK]

Nothing to show but I fixed my compressor. It was leaking as the result of the type of quick change fitting that came on the compressor and the cheap fittings I got from Menards for the air hose. I ended up going to Runnings Fleet and Farm and got all new, made in the USA type 'M' Milton fittings for the compressor and the air hose. No more leaks. I chucked the old fittings into the trash where they belong.

Ed

[Mayhem]

Nice job Ken but I wonder if this will now make it more chatter prone?