Need a bed surface ground.

[Smi_tty]

A while back I purchased a derelect rf30 milling machine. I restored it, and went to go tram the head, and I believe the bed needs to be surface ground soI can get it dialed in properly (the top was pretty rough when I got it). Its about 10” x 24” in size.

Are there any members here that could do this for me? Name the fee, and I will pay it.

 

[Dabbler]

There are several places with large enough surface grinders like Moore's industrial. You might get a good deal if you're not in a rush and with the downturn, and all...

 

[DavidR8]

A while back I purchased a derelect rf30 milling machine. I restored it, and went to go tram the head, and I believe the bed needs to be surface ground soI can get it dialed in properly (the top was pretty rough when I got it). Its about 10” x 24” in size.

Are there any members here that could do this for me? Name the fee, and I will pay it.

Did you buy that RF that was in pieces?

 

[YYCHM]

Did you buy that RF that was in pieces?

Hard to say, he hasn't published his location. I was wondering the same.

 

[Bradells]

I can't say for personal machines, but commercial is hurting. I've been dealing with Ryan @ Aaron Machine Shop (Blackfoot/Glenmore) for the past few months for some larger lathe work that I can't do.

They've been very helpful and reasonable with rates.


Brad

 

[Smi_tty]

I purchased it from a guy on Kijiji - it was in pieces and kicked to shit. Like I bought it, and said to myself when I got it home “what have I done?”. Not one to back down from a challenge, I committed to getting this thing restored. Someone had tipped the unit over and dropped it and cracked the base and handle off at one point. It was ready for the scrapyard.

My uncle welded the base up, and i structurally bonded a plate on top for reinforcement. I have a ton of hours into this thing. I lost the before pics which sucks, but you should have seen this turd when I got it.

Here she is now....

 

[Smi_tty]

Problem is I am starting from ground zero on learning how to use this thing ...i was able to restore it though without an instruction manual!

 

[Dabbler]

Hey you've done a nice job on the restore!!!

A way to get experience, do some tooling up, and avoid the prospect of taking it all apart again, is to do the job yourself... I'm not kidding. For a little mill like that, doing fly cutting will get you to accuracy beyond what you need.

I won't go into all the details here (boring) but we might discuss how you can get full coverage and accuracy offline.

 

[Tozguy]

Smitty, great job, nice looking mill.

Dabbler, it is more than OK with me if you want to discuss it here. I would like to learn how to do that too.

 

[Smi_tty]

i’m okay with it to.

 

[YYCHM]

Looks good to me. That was the one offered up in Calgary as "In parts make me an offer"? What did it cost you if you don't mind sharing? I was very very tempted, but there was the nagging question as to whether all the parts were actually there. I see the belt cover isn't original. Does it have the original steel pulleys?

The table doesn't look bad at all from your images. Perhaps post a better image of the table and indicate why you think it needs to be re-surfaced.

 

[Smi_tty]

That is the one. I had to sand the surface of the table because of all the rust. That plus a wire wheel. I paid 300 for it. Really though, I would have been better off getting a new one...the thing was destroyed. That being said, Its finished and ready for some action.

I spent a lot of time tramming it and was only able to get it to within .007 - but the numbers were inconsistent on the table. Which leads me to believe that I need to get the table surface ground, so that I know I am tramming correctly.

 

[Smi_tty]

I started using it the other day, snd kind of want to install a power feed on it now. It gets tiring using it manuslly.

 

[Dabbler]

OK here goes:

.007 tramming won't quite do in this scenario. there's a bunch of factors, and I'd have to see your machine before trying to be too specific as to what went wrong. I was hoping for around .001 or .002 tramming, which should be doable on your machine. If your table is too rough due to the rust, etc, hand stone out the biggest lumps and place a parallel on its side for a reference surface. Get it trammed in X, then roatate the parallel 90 degress and tram in Y. Repeat ad nausium until your tram at 5" or so is in the order of .002 or less.

To fly cut the table:

You need a pretty wide arc fly cutter, in the order of 4-4.5 inches. You can research which one you can afford.

Move your table to one side and rotate your head to that side. You want to be able to cover the corner of the table.

Take a cut moving the table toward the centre as far as your lead screw takes you. Repeat until your surface is acceptable.

Now position your table and head to cover the other corner of the table at the same end, and take your cuts until you just intersect the other cut. this is why your tramming has to be good. If you could using a 9" cutter, you could do it in one pass and it would be self correcting.

Repeat, starting at the other end of the table.

-----------------------
Waaay back when I had my first mill, my T slots were wide enough for a 1/2 inch hold down nut, but the slot was too narrow for a 1/2 inch stud. So I did this exact same thing for my slots and opened them up .010 to use the bigger hold down set. The joins of the milling cuts were within .0005 and could only be read on a tenths indicator.
----------------------

Let me know what parts I may have left out, and what needs further explanation.

 

[YYCHM]

Doh….I didn't realize you were talking fly cutting the table

 

[RobinHood]

I spent a lot of time tramming it and was only able to get it to within .007 - but the numbers were inconsistent on the table.

Just out of curiosity: how are you trying to tram the head to your table? Are you using shim stock under the column mounting flange? Either the top one or the bottom one.




i believe there is no other way to influence the relationship between the head and the table on these mills, except by shimming.

having to weld the base, probably distorted the base. So the column mounting surfaces also moved - thus possibly your tramming problem.

 

[YYCHM]

Man @RobinHood you have a good eye for detail... That machine is different from mine. My column is one piece bolted to the base. I'm wondering if that pedestal is integral with the base casting? Interesting...

 

[PeterT]

The mill base and lower column stub may well be integrally cast together, but quill alignment relative to table is influenced by the bolted faces. As an example just eyeballing the dimensions, lets say he had 0.002" of gap deviation under a bolt (one of the upper blue circles). That's about half the thickness of a sheet of paper. If the column is 6" wide, that's a rise of 0.001" per 3". So if he used say a 12" radius arm to check tram in X-axis, that would be 0.004" per side or 0.008" total dial deviation. If the assembly was perfect to begin with, but the column stub got bent by damage, or welding heat or whatever, all it takes is a tiny amount of deviation on the short distance flange surface to exaggerate into tram runout over a larger distance. Even a bit of dried paint or casting burr would do it. One can visualize that if 1 bolt was artificially shimmed & the other 3 tightened, you would have a different tram deviation result in X vs Y because of how the spindle is orientated relative to the bolts.

So the issue may be confined to the flange face as Rudy is suggesting which could be remediated with shims. But this assumes the table is perfectly flat & not giving a false reading. If the column & spindle was perfectly square but the table is bowed and/or twisted, the dial will pick this up in the tram test.

 

[Smi_tty]

The base was pretty smashed up, i took a chance on it and it works, just trying to get it dialled in the best I can. Not sure which other steps to take , i messed around with it and shims for hours.
For the type of parts i will be building, it will suffice. That being said, if there is a way to make it tram perfectly, then i’m all ears.

https://canadianhobbymetalworkers.com/threads/for-someone-with-a-bit-of-time-in-calgary.2074/

After the welding was done, I built a steel plate ( 3/16” thick) with two bends in it, and structurally bonded it on top of the casting, from front to back, on the left side where it was cracked originally. Two holes were drilled for the bolts to slip through for mounting. if you look closely at the left side of the base, you can see the reinforcement plate which I am talking about.

 

[Smi_tty]

The mill base and lower column stub may well be integrally cast together, but quill alignment relative to table is influenced by the bolted faces. As an example just eyeballing the dimensions, lets say he had 0.002" of gap deviation under a bolt (one of the upper blue circles). That's about half the thickness of a sheet of paper. If the column is 6" wide, that's a rise of 0.001" per 3". So if he used say a 12" radius arm to check tram in X-axis, that would be 0.004" per side or 0.008" total dial deviation. If the assembly was perfect to begin with, but the column stub got bent by damage, or welding heat or whatever, all it takes is a tiny amount of deviation on the short distance flange surface to exaggerate into tram runout over a larger distance. Even a bit of dried paint or casting burr would do it. One can visualize that if 1 bolt was artificially shimmed & the other 3 tightened, you would have a different tram deviation result in X vs Y because of how the spindle is orientated relative to the bolts.

So the issue may be confined to the flange face as Rudy is suggesting which could be remediated with shims. But this assumes the table is perfectly flat & not giving a false reading. If the column & spindle was perfectly square but the table is bowed and/or twisted, the dial will pick this up in the tram test.

is there a way to measure if the table is bowed or twisted?

In theory, the shimming works. However, in practice, which I did for several hours, it is not as simple as just shimming one corner (i tried tgat method, and ended up with shims somewhere between two bolts actually).