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Sending lathe bed out for grinding and need advice.

nc5a

Cast Iron
Joined
Jan 4, 2013
Location
Alaska
Should I have the grinder remove just enough metal to clean up the surfaces? Or remove the same amount of material from all surfaces to make it easier to bring the saddle back into alignment using Turcite, Roulon or Moglice?




Crated and ready to go



Surface "A" has the most wear, approx 0.010"
 
You'd be best just to have the flats E & F ground on the same plane. That will become reference /datum level. All the rest minimum 100% clean up.

Regards Phil.
 
I love your drawing with measurements so you know how much they grind off. This is so important because many times over the years I have asked the grinding company to keep track and the operator forgets and doesn't write down how much he removed or writes down a guess. Those numbers before and after can be used to calculate how much you will need to machine off the bottom of the saddle to accomidate Rulon 142 / Turcite B / Mogice to use. I have been using the .047" thickness for the last few years and before that .062. Those thickness's are good as you can cut oil grooves in it and not cut through it. Also have room to scrape it.

Using thinner material will wear through faster and you will have issues cutting the oil grooves. If your going thinner like .032 be careful with milling off the saddle so only light scraping is needed.

Before milling off the saddle, I would cut plastic shim and fit in under the ways until the saddle bottom where the carriage bolts too is parallel to the bed ways and the top of saddle flats are also parallel to the bottom as that is "original". The bottom of the saddle ways will be worn on chuck side front inside way the most. Then calculate how much Iron you will need to mill off adding the material ground off the bed plus wear subtracting off the Rulon thickness plus a minimum of .003" glue line. Rulon uses .003" glass beads in epoxy g for that glue thickness.

Many times installers spread the glue on way to thick when only a small amount is needed. It dries faster too. Follow the material manufacturers instructions on gluing. I also spray the ground bed ways with a wax release agent and set the saddle on the bed with the Rulon under it to dry there. I also do a dry run with no glue and take my measurement before glue is applied. It's a good way to be sure everything fits and you have the lifting procedures down pat. Sometimes I replace the rack and rack pinion and while calculating the Rulon Thickness I screw on the carriage and check the rack/pinion clearance. As Phil said make sure the 2 flats are ground the same thickness so you can measure the saddle unworn top so it is parallel front to back and side to side. I also leave the front of the saddle plus about .001" so as it wears it wears better. Also you know the saddle must be scraped square to bed so the cross-slide faces hollow.

Sorry for the long reply, but many read this forum and won't know what to do as I know you do. Thanks for spreading the knowledge. Rich
 
We used to grind the turcite in the saddle to size Or even kept the ways cast iron You have to compensate position of the carriage by grinding somewhat off the top of it and make the gear for the crossslide a special smaller one if need be
Mesuare how high the crossslide is above surface F on the drawing from OP
Mill out some material. Apply turcite Then pre-grind the turcite in the right angles
Then grind the bed
Then place the saddle on the bed
Indicate the top of the saddle on the ways of the crosslide (Best of coarse if these are ground or scraped already)
These must be parrallel to surface F
Now you can determen how much and where you have to grind of the turcite
(If its high on the back side the saddle touches high on surface A and left on surface F Measure that distance And indicate over that same distance on top of the saddle Now you know inmediatly how much to take off of the mating surface of F)
Keep the saddle a bit higher as the saddle had some wear
If you have a decent grinder you just have to scrape it a couple of times to fit and perhaps releave the middle
Turcite grinds real easy

Peter
 
Darn, super info with the drawing, just wish you were sending this to me!

We have a bit of real estate to cover between Alaska and Wisconsin.......
 
Darn, super info with the drawing, just wish you were sending this to me!

We have a bit of real estate to cover between Alaska and Wisconsin.......

Alaska ain't close to much, regardless, and that's a featherweight as lathe beds go.

Wisconsin shouldn't be all that much higher r/t freight than uppa left coast, Canada or USA.
 
Did you check with Shane Carr or member named Collector? He is near Vancouver BC and has 2 way grinders in his shop. He also has taken 2 scraping classes. He was at the one I just did in Rockford. He wrote in that thread this morning about how he got info on his 4 Rockford machines he has in his shop. Shane wears several hats and is a Journeyman in all of them. Carr's Machining Ltd. | Facility
 
I did considerable research to find a reputable way grinder close to Alaska and the best I could do was Schaffer Grinding in Montebello CA. They quoted the job in August of 2016. Obviously I didn't get it shipped back then but they are still honoring their quote from 7 months ago. The quote was $475 for the bed based on max stock removal of 0.010" from all way surfaces. I estimate my worst surface will require right at 0.010".

Current freight quotes are $507 down and $592 back for a total of $1574 for freight and grinding. If the bed requires more than 0.010" the grinding cost will probably go up some.

I will try to do a decent job documenting this rebuild and will certainly be asking for advice from time to time.

I asked Schaffer Grinding to grind way surfaces "E" and "F" so they are on the same plane since they will become my reference and the other surfaces grind to clean up. I will machine the saddle and tailstock in my shop.

Richard, are you and your wife still coming to Alaska this Summer, if so let me know your schedule and maybe we can do something fun.

Ron
 
I did considerable research to find a reputable way grinder close to Alaska and the best I could do was Schaffer Grinding in Montebello CA.

Schaffer is the go to shop for way grinding in So Cal, there are others but Schaffer would be 1st choice. I have a Hardinge HLV that needs the bed ground, they'll be doing the work.
 
Well I am not going to really get into it deep but to grind this lathe bed for $475 I would take it and run. I know Schaeffer is a good shop. But on the same hand maybe at these prices they charge that is whey they have not bought a new machine since my guess is the early 80's. When I spoke to their shop manager a while back after I bought a 96" mattison he mentioned how they work was just tough and they could not charge jobs out like they used to. The machine I bought was theirs and was trying to figure out why the sold it.

To do this job right if I were to do it I would be grinding 11 surfaces. I don't know why you would not want to grind the tail stock surfaces in the first case. Second reason I grind more surfaces is when you go to align the saddle having some straight edges, the sides of the ways, helps out and since the lathe bed is already on the machine it does not take much more time, but helps in alignment.

There is as well another shop in South Cali,

714-228-21 | Quality Grinding Co. Inc. - Home

I have to think they are going to spend at lease 6-8 hours on this. Even at the low end of 6 hrs making $80/ hr on a way grinder is pretty light.
 
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To do this job right if I were to do it I would be grinding 11 surfaces. I don't know why you would not want to grind the tail stock surfaces in the first case. Second reason I grind more surfaces is when you go to align the saddle having some straight edges, the sides of the ways, helps out and since the lathe bed is already on the machine it does not take much more time, but helps in alignment.

I have to think they are going to spend at lease 6-8 hours on this. Even at the low end of 6 hrs making $80/ hr on a way grinder is pretty light.

Cash, you bring up excellent points regarding what surfaces will be ground. So I ask, how does a grinder know which surfaces are critical and which are not? Is it up to the owner of the machine to inform the grinder which surfaces need to be ground and how much to grind or at least guidelines with limits? Referring to the drawing of my bed I see potentially 15 surfaces that could be ground in which 5 of them are not critical.

Also, who prepares the base of the bed? I cleaned mine but I didn't stone it figuring the grinder would do that during setup. But what if a grinder get a filthy machine, is there an extra cost for cleaning before setting it on the grinder? Or, do they plop it on the grinder with minimal cleaning and grind away?

What about insurance, do you guys insure your machines when sent out for repair or in this case way grinding? If my bed is damaged, lost or somehow screwed up beyond repair I'd be out of luck because there is no way in hell another bed could be found to replace it. I've had this lathe 20 plus years and have never seen another like it. There are Saimp lathes around mind you but not many and certainly none like mine, that I've seen anyway.

I'd really like to watch them grind the bed, maybe I'll ask them, you never know. Cash do you allow customers to watch the grinding operation?

Ron
 
G should be ground parallel with F and D parallel as well.

I am not sure the value of all the measurements. For example if G and F are ground, when you get it back and they say not how much was taken off either, how will you know.

Measurements should have been taken from the base of the bed as you know it will not be molested by the grinder.

You really only need to know how much the saddle ways were taken down anyway. The tailstock is irrelevant as you build it up to spindle height.

Not sure how the headstock is fitted on that late, but you would wants its sitting surface ground as well, in the same plane as the rest of the bed.

Personally I have no idea how they could do it for that money. I would have thought triple that amount. I guess they have a coolant equipped grinder and can really take metal off fast without having to worry about heat issues.
 
When we have done jobs for people in the past I always welcome their input. I want to know what they will be doing with the machine after I grind the bed. Will they rescrape the saddle? Moglice? add turcite ect. I agree with you 15 surfaces, this would include the flats at the top of the vees.

I ask for the machine to be torn down and clean. The first thing we do is put it up on our granite and inspect the surfaces.

See an example here.

Instagram

Then we discuss all the surfaces we will grind and agree on the reasons why we want to grind specific surfaces. For example, I like to grind the outside surfaces, on your print this would be the vertical surfaces. You do not need these surfaces ground for operation of the machine but when you want to align you saddle and spindle it is nice to know these surfaces are square. We have a granite square with parallels molded into it, we use this to line things up.

See this set up here.

Instagram

As far as insurance goes, our insurance as well as whoever would be hauling, rigging and working on the machine has insurance. I always use reputable people and so far I have never had a problem. Knock on wood.

I would have no problem having a customer in to watch the process. Some shops are funny about this, they have their "secrets". Unless you are going out to buy a way grinder there is really no secret.

And grinding.

Instagram
 
I have not used them but they did ask me for a reference on who to rebuild magnetic chucks so we had some back and forth.

what type / make of machine for that mag chuck rebuild Cash? any idea? I ran out of parts building the machine they started me on Monday, and while I don't wind the coils, I do clean and inspect. Just.... tell them to knock at least SOME of the 2 inches of rust / crud / notsurewhat stuff off.
 
I love your drawing with measurements so you know how much they grind off.

Rich

I do not think these measurements are accurate enough to be of any help in that regard
Also one of the important ones is missing The possition of the front V-way is not determened
Thats very hard to determen anyhow IMHO Possible but hard

Peter
 
I do not think these measurements are accurate enough to be of any help in that regard
Also one of the important ones is missing The possition of the front V-way is not determened
Thats very hard to determen anyhow IMHO Possible but hard

Peter

I am complimenting his drawing. He is a very smart guy and I encourage people to be a detective and measure before sending out the plan marking where you want it ground. Ron can call the grinding company and refer to the drawing and make sense in the conversation with the grinding shop 2000 miles away. Nothing wrong with his drawing!
He may have another drawing with more precise measurements.

Sending a lathe bed out to get it ground with-out taking measurement in my opinion is stupid and your looking for trouble. Why do some always look for something negative to say when we discuss positive things?

He said the ways are only worn .010, so if hard ways are worn .010" then the softer ways are probably worn .020 the alignment of the rack pinion and feed shafts are fixed. I am assuming he will apply Turcite or Rulon as this will make it a better then new machine. Making a smaller cross feed gear is not the way to compensate for the lowering of the saddle. I have never heard of a professional doing this.

Some machines have a camshaft on that gear, but lowering .030" and not bringing it back to the original height will make the feed shafts bind. As I said I use plastic shims or Rulon shims under the saddle to get the alignment before gluing and final assembly.

As I said there are rules we follow or steps we follow. Ron is a retired Journeyman Machinist and inventor, not some rookie. He doesn't need a lot of help here. Lets let him show us what he will do on his lathe rebuild. Rich
 
I am complimenting his drawing. He is a very smart guy and I encourage people to be a detective and measure before sending out the plan marking where you want it ground. Ron can call the grinding company and refer to the drawing and make sense in the conversation with the grinding shop 2000 miles away. Nothing wrong with his drawing!
He may have another drawing with more precise measurements.

Sending a lathe bed out to get it ground with-out taking measurement in my opinion is stupid and your looking for trouble. Why do some always look for something negative to say when we discuss positive things?

He said the ways are only worn .010, so if hard ways are worn .010" then the softer ways are probably worn .020 the alignment of the rack pinion and feed shafts are fixed. I am assuming he will apply Turcite or Rulon as this will make it a better then new machine. Making a smaller cross feed gear is not the way to compensate for the lowering of the saddle. I have never heard of a professional doing this.

Some machines have a camshaft on that gear, but lowering .030" and not bringing it back to the original height will make the feed shafts bind. As I said I use plastic shims or Rulon shims under the saddle to get the alignment before gluing and final assembly.

As I said there are rules we follow or steps we follow. Ron is a retired Journeyman Machinist and inventor, not some rookie. He doesn't need a lot of help here. Lets let him show us what he will do on his lathe rebuild. Rich

Why do some always look for something negative to say when we discuss positive things?

Oke then we must keep it always positive on this board Sorry my fault
Always agree with the King ????? Come on Richard That would be no fun

Making a smaller cross feed gear is not the way to compensate for the lowering of the saddle. I have never heard of a professional doing this.

Why not ?
I am not a proffessional rebuilder and I have all respect for them But for those gears I got advice from a proffessional engineer in gearmaking Also we could make those gears in house
If you want to keep the ways original CI on CI for one reasson or the other and do not want to use Turcite you eighter have to lower the spindles along with the feed gearbox or take something of the top of the carriage and then set the centre to centre distance of the gears for the crossfeed smaller
I am aware that this might not be possible on all lathes
AFAIK Ruemema is not using Rulon or SKC And AFAIK a schaublin 135 is CI on CI

Peter
 








 
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