Good on you Ola, sounds like you have it sussed
Couple of things that come to mind. If you are going to make a guide bars, trust me, you should make and use five of them. Make sure the M8 x 1.25 pitch you cut into the end of the 12mm guide bars are done in the lathe with a spirex tap mounted in the tail stock of course(keeps everything true). Obviously make sure that before you cut the threads to relief counter-bore them to a depth of the length of the head stud shoulder +1.0mm. This will not only alloy them to screw all the way on, but also save you needlessly cutting extra thread into the end of them. Face the end, so that they nip up squarely and perpendicular to machined alloy face of the cylinder top. No need to over tighten them. Doesn't hurt to machine a slight tapper on the opposite end of the guide bars either, as a lead-in off course. Just makes it quicker and easier when dropping the liner into place on the way from the oven to the press.
You can machine up a stepped pushing plate if you please? I prefer to use dual plates with a very snug fitting center-bolt to amalgamate. Very important to leave the job in the press under pressure as it cools to ambient. Make sure to support as much of the liner hat as possible. The OD of the the pressing re-entery push (tool)plate should be as great as possible to extend just about all the way out to the guide bars. That way the liner hat is supported when pushed firmly home, onto the area against the top of the cylinder.
For optimum heat transfer between the two, you want a minimum shrink fit of 0.006", but no more than a max of 0.014".
To prevent heavy galling, break all sharp cylinder and liner port edges with a bit of 600 grit, just a mick hair. I have the measured liner ready with a film of loctite brand "nickel based anti sieze". Some will tell you to use special heat sink grease to aid heat transfer to the "Alloy atmospheric heat exchanger"(cylinder), but in the case of Maico's high aluminum content casting, they use the heaviest permissible shrink-fit interference allowable between these two dissimilar metals to actually engineer the max transmission of heat between the two materials.
Remember to do a test run, to have all your tooling and gloves set up ready. Do a dry run from the oven to the press. I do it in the house too, up to 250 degree, no problems.
And most of all remember that
prior preparation will prevent a piss poor performance.
If you would like to share any more thoughts before you get to the port trimming stage? just say.
PS; If your lathe is big enough? It is a really good idea to true the base surface of the cylinder by fly cutting it at the finish of the job.
