atpkinesin wrote:have you thought about threaded rod for the vertical supports? woops - edited due to saturday night engineering woops. threaded rods would deflect too much

Yeah, I don't think there would be an efficient size that would work for rod. Stainless tubing would probably work and could run wires and tubing through that.

I've planned the metric and BSPP route, it looks like it will be simpler and require less fittings. Mostly because I can get a nice OPV with integrated T into it. Unless anyone thinks there's a better OPV alternative, I'm thinking of going with this one assuming connections are 1/8" BSPP:
https://espressocare.com/products/item/ ... -valve-opv

In the beginning for testing I'll also use some 6mm teflon tubing, but I plan to swap it out for copper once I have the configuration finalized. It may change and locate the TB in a different location, or with 2 TBs I may need slightly different configuration.

Will post a new drawing soon since I still don't have the parts. Hoping main ones will ship out Monday.

BSPP and 6mm tubing plan, I think I will go this route, as far as I'm aware the TB uses 6mm tubing internally, so I don't see an advantage to going with anything larger.

Got my grouphead today and attempted a pressure test using 3/8" NPT fitting to the back. It's a little loose, and even with a decent amount of teflon tape there's a small drip. 3/8 BSTP is smaller, and 1/2" NPT doesn't fit for sure. 1/2" BSTP may fit, but it's awfully close to 1/2" NPT. I'm surprised if it would be a non-standard thread, and I'm guessing it must be a tapered thread and not a straight thread. Will post what I can find out.

Useful tests for flow rate etc it looks like can only be done once I can mount the group to my plate and to a frame. There's no way to safely pull the handle down otherwise, not to mention how I would get the lever back up once it was down without being bolted to something sturdy.

I don't think that the thread is a taper, as the seal appears to be made against the mounting surface. It could just be a standard metric thread, I'll check.

Yeah I've been looking at thread charts and using my calipers. Best guess I have right now is a straight M18x1.5 or M17x1.5 thread. I'm planning to take the group into the hardware store and check it out. I doubt they'll have any adapters, but McMaster has them at least.

http://vancouver.craigslist.ca/nvn/app/5443869169.html (2 group machine for $450 CDN)

Would be a perfect parts machine for this project - maybe someone else in the Vancouver area could pick it up? I'd do it but I have a backlog of machines to restore...

Certainly would be worth $450 to me, but a full restore would depend on condition. For parts for this project it looks great! Hope someone up there will pick it up and follow along.

I checked out the hardware store again, but was a bust. Their largest metric bolt was M16, but I'm fairly sure it's M18x1.5 threaded. I did get a factory part with a threaded male end to probably 10mm copper tubing, so will check that out when it comes, but was hoping to document more about this group than is available.

The 18mm X 1.5mm is a standard metric size. Adapter between 3/8 pipe and 18X1.5. http://www.mcmaster.com/#metal-british- ... s/=1130yml

That is my plan depending on how the factory soldered pipe works out. But it would be nice to have been able to verify the threads before ordering. I'm 90% sure, but you never know. It's much harder to measure female threads than male to match them up to charts. So I'll probably just wait till next week when those parts arrive.

I'm back looking at a frame again, almost bought some green painted strut channel at Home Depot, but they couldn't cut it in half for me to take it home. It was $20 for 10 ft. McMaster sells it in 1.5 ft pieces, both painted or stainless but obviously more expensive + shipping... I still like the idea of strut channel, I'm sure L angle mild steel welded would be cheaper, but after painting or powder coating it then not again. 304 stainless is about $1 per inch in strut, so it would cost me around $75-100 + hardware.

If you have an 18mm spark plug see if it screws in or an old O2 sensor, they are both 18mm. There are face seal fittings and they are a odd size. Available in BSPP and SAE.