Guidance requested on 8520 maintenance

I would call these guys - they have acme screws and nuts. I bet McMaster Carr buys from them.
 
I ordered the acme screw and bronze nut from McMaster and made the parts on my lathe. It was easier to create a new insert in the casting for the nut than it was to machine the nut down to a shape like in the drawing. The Y leadscrew works great now.

The Y movement isn't great because of the wear on the ways. I cleaned the gunk and lightly hit it with a whetstone to see if it would help (and it did a tiny bit), but it didn't do much. I talked to a local guy who estimated about $1500 to scrape it. I haven't contacted Shaffer Grinding yet.
I don't have it all the way together yet to measure how far off it is. It will have significant slop in the middle if adjust the gib for full Y travel, otherwise it will only have a few inches of travel if I adjust the gib for the wear.

I'm a beginner to this, so I don't feel there's real value in dropping $1500 on it now. OTOH, I imagine that a machine out of adjustment will make learning harder. I'll have to think about that, or live with it for now and fix it later.
 
I ordered the acme screw and bronze nut from McMaster and made the parts on my lathe. It was easier to create a new insert in the casting for the nut than it was to machine the nut down to a shape like in the drawing. The Y leadscrew works great now.

The Y movement isn't great because of the wear on the ways. I cleaned the gunk and lightly hit it with a whetstone to see if it would help (and it did a tiny bit), but it didn't do much. I talked to a local guy who estimated about $1500 to scrape it. I haven't contacted Shaffer Grinding yet.
I don't have it all the way together yet to measure how far off it is. It will have significant slop in the middle if adjust the gib for full Y travel, otherwise it will only have a few inches of travel if I adjust the gib for the wear.

I'm a beginner to this, so I don't feel there's real value in dropping $1500 on it now. OTOH, I imagine that a machine out of adjustment will make learning harder. I'll have to think about that, or live with it for now and fix it later.
run it as is. Mine is loose in the middle, and tight on the ends. So I run it so it's good in the middle, then back off slightly so it's a little loose. I can use the table lock to tighten up the gib a little if needed. I would not scrape it in unless it was really far out, and if it were, you probably need to grind it first.
 
It looks like running a 2MT to ER-20 adapter is a good way to avoid messing with the drawbar every time I change a tool. Anyone have a recommendation on a good brand or source? I like to avoid buying chinese when I can reasonably avoid it. Apparently ETM makes one in Israel. Other options?

I have the mill back together now and it runs nice and quiet. I need to figure out what to do for a base - mine came with a homemade base but the head of the mill only comes to the middle of my chest, so it will need to be a lot higher. Before I look into having a base welded up, is there another alternative I should be thinking about?
 
It looks like running a 2MT to ER-20 adapter is a good way to avoid messing with the drawbar every time I change a tool. Anyone have a recommendation on a good brand or source? I like to avoid buying chinese when I can reasonably avoid it. Apparently ETM makes one in Israel. Other options?

I have the mill back together now and it runs nice and quiet. I need to figure out what to do for a base - mine came with a homemade base but the head of the mill only comes to the middle of my chest, so it will need to be a lot higher. Before I look into having a base welded up, is there another alternative I should be thinking about?
I would recommend an ER32 or 40. The 20 is small. I have 5/8 and 3/4 end mills.
I have an ETM, very nice quality.
My mill has the original base. The head is approx eye level, the draw bar is at 6' 3 maybe.
 
I would recommend an ER32 or 40. The 20 is small. I have 5/8 and 3/4 end mills.
I have an ETM, very nice quality.
My mill has the original base. The head is approx eye level, the draw bar is at 6' 3 maybe.
Thanks, that makes sense. I ended up ordering an ER25 today because I found a good price on the ETM. I didn't see any ER32 on MT2 shanks anyway. I'm coming from a Taig with an ER16, so I don't have any end mills larger than 3/8.
 
Thanks, that makes sense. I ended up ordering an ER25 today because I found a good price on the ETM. I didn't see any ER32 on MT2 shanks anyway. I'm coming from a Taig with an ER16, so I don't have any end mills larger than 3/8.
yes, but you will. I have many 1/2 because they are more stout. You will too. Just because you have 3/8 now, does not mean you won't in the future.
edit: I guess 1/2 is covered by er25, so good on you. As far as larger, agreed, I don't use my 3/4 often.
 
When I run my mill, I'm getting a good bit of noise from the area of the pulley brake. The sound is something like a ring.

I'm pretty sure I have it put together correctly, though I'm missing the brake shaft assembly (p/n 700-026). Thoughts on what it would be?
 
since you are missing the pin, I'll bet it is spinning around. I would remove the brake until you get a pin.
I wound up using a butterfly impact, so I don't need the brake.
 
since you are missing the pin, I'll bet it is spinning around. I would remove the brake until you get a pin.
I wound up using a butterfly impact, so I don't need the brake.
It was spinning around, so I made a shaft to hold it in place. I made the shaft roughly, so maybe needs to be done more carefully. I still hear a ringing sound when it's running. I don't mind some sound, but it's an irritating pitch that gets my tinnitus going, so it's got to go. I'll pull the brake if I need to, but would like to correct it if I can. Thanks
 
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