Scraping moves to the saddle

I spent the entire evening scraping. I'm satisfied that the bottom of the cross slide is done. It has a large number of evenly distributed bearing points and looks very nice. So, I spent some time on the top of the cross slide. It was somewhat rough and I figured it should be as flat as possible. I read one person online who had his ground, but several people said that can cause them to warp, ruining my scraping job on the bottom and I didn't really want to have to take it somewhere and pay to get something so small done. So, I figured I might as well scrape it. I started with a file to get the really high spots down, then worked it until I kinda got tired of working on it. It's flat over most of the surface and that entire area measures within 0.0005" relative to the bottom of the slide. I didn't really have to do much to make it level other than scrape down one corner a bit harder. It's not all of the way to the corners, though, so I'll have to spend some more time later. It appears to have bowed up just a little bit with time.

I was ready to try something else, so I launched into the saddle, using the cross slide as a reference. The picture above is after about four passes. The gib side had a ridge on the inside as would be expected and I've about got that down. It's clearly more worn toward the far end than near the apron end, again as would be expected. I really don't think this scraping is going to take too long to get done, given the progress I make already. In general, this machine was not that badly worn when I got it.

I spent quite a bit of time grinding the scraper bit. The large flat surfaces on the bottom and top of the cross slide were easy, but now I'm having to get into dovetails, so I ground the sides and front back so it's more like a chisel. That seems to work pretty well. I don't think I'm scratching the dovetail side very much and I'll be back to scratch it a bunch later on, anyway.

The plan is to get the saddle bottom flat, then use the scraping plate I bought to get the saddle dovetails flat and parallel. Then I'll use that as a template for the cross slide dovetail and the tapered gib.

eBay purchases

eBay continues to be a great source for this project. My lathe was missing the threading chart. It doesn't effect the functionality at all, but it's just an annoyance. Well, tonight I picked one up on eBay for $12. I also got a set of half-nuts. They are used, but that does avoid me having to try to make some. I was surprised to get them for just over $40. I heard the last set to go on eBay went for more than $100. Guess there's not as many people buying right now.

I've not had time to get back to the scraping project. It was getting close, but I take a small amount off at a time, so it goes pretty slow. I'll probably get the bottom done this weekend sometime, then move to the next part.

Scraping on the cross slide

I launched into the scraping project tonight on the cross slide bottom. It definitely had quite a bit of wear on it. I should have taken pictures when I started of the blue in only a small section of one side and in the middle of the other. After about a zillion passes, it's all pretty flat, but I will have to do more passes to get the bearing points distributed nicely. It got late and I had to quit for the night. This picture has some blue on it so you can see some of the spots. I'm having trouble getting the blue to transfer brightly. Instead it looks very light and is hard to see. I'm going to have to get a good fluorescent light to work on this more.

Attaching the bed

The bed and the pedestals are now attached! I figure the bed and risers is just over 200 pounds. I made a simple cantilever lift from 2x6's so I could easily set the bed down on the pedestals with little effort. That hydraulic table is one of the handiest things I've ever purchased. Anyway, it's at home now. I attached the foot bracket on the other end, but I need to get a couple bolts to put on the other two feet. Then I can look at leveling in place.

I cut two pieces of wood that go between the bed and the chip tray. With them in place I can slide the lift table under the whole thing and lift it right up to move around. Works just fine.

I intentionally filed the scraping experiment so I could do it again, getting more practice. I'm getting better, I think. You can't really mess things up very quickly, since the process removes so little material at a time. I picked up an ink roller and that made all of the difference in the world on getting good transfers to the high spots. I may be confident enough pretty soon to look at that cross slide. I found a set of scraping plates including one flat and one 60 degree on eBay and got the set on a Make Offer. I had been concerned about how to make the 60 degree reference I would need and this solved that problem quite handily. These were supposed to have been made in 1954, which makes them five years older than I am. But, good tools should last longer than we do.

The first scraping experiment

I had an old 9x20 lathe part sitting around, so I'm using it as a scraping experiment. This is the first attempt. I don't have the geometry of the scraper tip quite right, yet. I really wish I had a diamond wheel to grind with. Instead, I'm working it by hand using a diamond hone. It's hard to keep it from being a convex end that way and the middle is hard to get has sharp as the sides for some reason. It's very sharp, though. I don't need much pressure to scrape this cast iron at all. It's very flat now, but has some gouges. I'll work on the scraper a bit and then try again. I may even mess it up a bit first.

I'm also having trouble getting bright transfers from the surface plate. I'm going to pick up a roller tomorrow. Most of the advise I've seen said to roll the ink out. I tried spreading with a rag and by hand and it's hard to get it thick enough to mark, but not so thick it marks everything. I can get it thin enough, but it's hard to see the markings sometimes.

It looks nicer in person than in the picture. The picture shows every flaw. But, it looks almost like real hand scraping.

Starting the scraping project

I'm starting in on the scraping project. I'm making my own carbide scraper from 1/2" drill rod. I milled a slot in the end for a carbide blank and hold it in with two 6-32 set screws. It's done and seems to hold very tight. I started grinding the carbide a bit on the grinder, then fine tuned it with diamond laps. I still need to put more curve into it, but I do have an initial edge.

I couldn't resist trying it. Enco sent me another surface plate and this one arrived okay. I have a 9x20 lathe compound part that I'm going to experiment with. I put some Dykem high spot blue on the surface plate and then the part. The high spots were very clear and I was able to make good progress in a few passes on getting them to spread out a bit. Of course, I don't have a good way to hold the part yet and need to put a handle on the scraper, but a quick try seems to indicate it works pretty good. I was definately able to scrape very tiny shavings where I needed to. But, I'm going to spend quite a bit of time practicing before I start scraping real lathe parts.