Hmmmm
We use a lot of sheet wax at work. The only grade I am familiar with is fairly hard , A lot harder than I would be likely to use. Very hard, compared to the modeling clay that we also use, literally by the ton as we make full size cars out of clay!

Anyhow. I will have to see if the adhesive backed sheet wax is available in softer grades.

Everywhere I have worked used the same stuff. We wax patterns up for metal thickness to cast Kirksite tooling. Also comes in shapes to make fillets in corners etc. Self adhesive as well but a bit softer.

Never looked into softer grades, waxing patterns makes you not really wanting to see any more of that stuff than you have to see!!!

Yep, a little oil or even talcum when dry is preferred to minimize sticking. Of course, valve to piston clearance is readily measured at all positions with feelers added between rocker and stem tip, position from degree wheel. A little calculation as well .

Well, I’m going to embark on my Saito 72 restoration. I recently purchased this used. Ad said it turns over smooth but it appears to have a seized bearing that spins on the crankshaft.

The stuff we use is marked " high temperature".
i never looked for anything different.

When we want to get a rigid measurable impression, we often do a "Bondo Squeeze" ; coat everything with mold release and squeeze poly body filler into the gap.

Pops apart with a very faithful , rigid impression.
We also use the dentist type compound and silicones for flexible impression .

Need to check with the local foundry supply dealer.

Thanks Glowgeek. It does indeed look lowtime. The valve adjustments look untouched. Piston and cylinder look pretty clean. I think the main bearing is a shielded bearing which made me think it was seized. The bearing does spin but not continuously. I still see some spin on the crankshaft. Since I have a new set of bearings I’m leaning towards replacing them. Or should I oil up the originals and run it as is?

A couple things. I wiped out the cam and lifters on my preowned 82 by running the bearings that came in it. In my case the crank had less rust nodules than yours appears to have but rust from the bearings got everywhere in the engine. Bearings are cheap insurance.

Completely disassemble every part of the engine and clean the parts Thouroughly.

Check the Cam for tappet dents. Check to see that the tappets will literally fall out of the tappet bores by inverting the cam gear housing. Clean the tappet bores with lacquer thinner and q-tips. Check the bottom of the tappets for beveling of edges. If the bevel has worn in more than 25% of the tappet diameter replace them.

Clean the int and exh valve stems with steel wool until they are bright and shiney all the way down to the valve caps. Use the smooth shank of a drill bit and laquer thinner to clean the valve guides. Don't clean the valve seats in the cylinders with anything besides a pencil eraser.

May seem like overkill to some but cleaning isn't expensive, parts are, and rust is THE saito killer.

Hint: It's a good idea to mark where the piston ring gap is located before completely removing the piston. I put a small scratch on the bottom of the cylinder to mark it. Reinstalling the ring gap in exactly the same location can sometimes lessen re-breakin time.

OK. New bearings it is. I already have them, why not use them. All good advise Glowgeek. Thanks. I’m in it for a new gasket set too since the cam housing gasket got destroyed. Are those aftermarket sets on eBay any good?

Yep, that is the same type sheet wax we use. We do metal stampings. Been at it for over 50 years.
We buy our sheet wax at a large foundry supply house. Foundries use patterns. When I entered the trade, the patterns were usually wood, often woods like mahogany , cherry etc. Now we use synthetic resins and urethane foams for that purpose. In the old days mostly hand mill work, now CNC. That is the trade.

The cast epoxy is but one material. We have acrylics, urethane, silicones etc on hand as well.
Rapid prototype parts from a variety of materials.

Same uses that we employ, same company. Likely the same product

I can relate to the water density chart 77 degrees I use one most of the time.

UI can send you a lab grade, graduated glass Burrette tube.

In fact I have 8 of them, which is more than I need.
No stop cocks but they are around.

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