Скачать с ютуб Myford 7x7 - saddles and cross slides - intro в хорошем качестве

Myford 7x7 - saddles and cross slides - intro

Saddles and Cross-slides My step by step procedure: Cross-slide 1) proving flat top as reference (scraping one.. others were ground) 2) measuring wear underside flats 3) rough scraping underside-flats 4) proving left side as reference 5) measuring dovetail 6) making groove in bottom of dovetail 7) rough scraping dovetail Saddle 8) mill off height on middle guide 9) finding and proving reference surfaces (some scraping) 10) scraping relief area top side to be flat to reference 11) making groove in bottom of dovetail 12) measuring flats top side 13) rough scraping flats top side 14) measuring dovetails 15) rough scraping dovetails 16) mill underside ways 17) apply Rulon wear material to flat- and rear vertical ways (draw out oil, clean, glue) 18) finish scrape ways (Rulon).. make relief in the middle area.. possibly flake 19) cut oil groove and drill holes 20) finish scrape saddle and cross-slide together 21) scrape "toe-in" angle in dovetail (or rear guideway) 22) finish scrape/fit hold down plate and gibs 23) assembly As usual when scraping worn pieces it becomes a search for the reference planes needed You want surfaces that represents the original planes, so it time to play detective (again) I found the undersides of the saddle to be useful for that purpose. These were the surfaces in the front where the apron mounts and at the rear where the hold down plate comes. Both pristine and 99% certain machined (ground) at the same time the did the ways. They also tested to be in the same plane as the unworn portion of the ways (small strips on either way where you still can see the orginal unworn scraping. Since the underside of the Myford saddles (apart from the later ones for power cross feed) have a strip of metal between the ways which protrudes a little over the front and rear surfaces I want to use for reference, I either had to use precision blocks in front and rear or get rid of enough material so it would be below the surfaces. Having decided to modify the saddle/bed "usage" to use the so called wide-guide principle, I no longer needed the middle part, hence I milled this down (just enough to get below the surfaces, so in desperation it can actually still be used as a guideway, although lacking a couple of mm in height.. or with an insert glued into it..). At least, I found it convenient to be able to put the saddle directly onto the surface plate and measure to this. Measurements were done with a dial test indicator for the flats and pins and a digital caliper for the dovetails (I know a micrometer is better, but mine doesn't fit ie. can't get the anvil low enough to measure across the diameter of the pins.. Repeated and averaged caliper readings will have to suffice, and I can seemingly measure to 1/100 mm (repeatedly) that way) For the cross-slide, the obvious choice of reference is the top flat surface, as well as one of the sides when doing the dovetail. I had already gotten most of the specimen ground on the top flat side, but scraped one (and will do another). I reckon it will be a matter of personal preference, ability and equipment.. and cost! whether one chooses to "machine" or "hand-workout" the pieces. Proving the left side as a reference meant I compared the readings from the other (right hand) side and also the inner surface where the gib blocks go against, to the chosen side. I also stoned it to have a greater percentage of surface bearing (not much, but some were quite "ding'ed" up and also had raised edges where the screws/holes were). One had to be scraped though.. The measurements and scraping will be covered in detail in the following video(s). So far I have completed the rough scraping for all cross-slides, so that they are plane and inline within 1/100 mm or better. Finish scraping for bearing points to this and the mating saddle will then follow later. So will the application of the Rulon and the milling of the saddle ways to prepare for this.