That's the height adjusting bolt/screw that rubs/rides on top of the rail? (not quite 15mm ;))

Kobus, how long did it take you to cut the angles?

I too used this method for faster grinding, then for final passes run disk parallel to the edges. When disk is used parallel it stops grinding after some time and become hot. So this method is perfect.

What did you guys do to stop the skate at the ends of the rails? Did you weld on a temporary stopping block to hit against the skate?

I simply used G clamp.

David,
That was me.

I tack welded a washer on the end so I had a nice positive stop while grinding. I was short on clamps and plentiful on washers!
...just another way - not the best, not the worst :)

I tack welded a washer on each end as well. If you use a C clamp (G clamp), the rail needs to be a little longer to allow for the clamp jaws.

Paul

The tilting of the skate can done left or right. You can either make the leading edge of the disk cut up or down. I would suggest that cutting down is the better option . . . . .to avoid the burr on the top face where the height screw rides.

I did the FRONT part down and it worked for me. With my little 500W Bosch it still took me about a hour on each Y-Rail. I clamped a piece of angle iron with a F-Clamp at each end for stops.

I think we just need to clarify the difference between "cutting" and "grinding"

The cutting takes place with the skate level - that is to remove the strip of the angle iron above the desired rail height.

The grinding takes place with the angle grinder held at a 45 deg position to enable the grinding of the bevel - its in this position that of a slight leading edge down attitude is beneficial. As Sean stated, the last few runs are taken with the skate level.

Also, two different types of disk are used for the two different procedures....
- thin Pferd disks for cutting (about 1 - 2 per rail)
- thick standard disks for bevel grinding (one is enough for all the work)

I second the slightly off-set adjustment nuts. The other thing I learned was that when the skate gets hard to push on the rail, take a wet rag and clean the vertical edges of the rail.

Update on my progress is not so good. Last night I started grinding the X-rails with a brand new 850 watt Einhell grinder. At first I notice a lot more power than my old 500watt Bosch that I used on my Y-Rails. But after about 40 minutes...poof...smoke...no more grinder. Just shows, some things are tougher in life than others. The Bosch is about 10 years old, did a lot of hard work, but is still going.

It looks like we are going to have to add a "Kill" register at the top of the forum for all the dead grinders...:) There is much to be said for a good brand name.

Good idea Alan. I thought Einhell was German...same as Bosch, but it just show you. I think it has to do with the new stuff. They are made to last just soooo long, then we are forced to buy a new one and the company smile. They did not think that we can kill it in the first day.

Einhell is either Swiss or German, but in name only. There must be a reason why one 500W grinder costs R299 and another one costs R899 - you gets what you pay for. ;)

No wonder, this one was R230.00 from Trade Centre:o

Gentlemen,
I think you are pushing your grinders to the limits. I am using Bosch G-100, 670w, 3.0 A, 11000 rpm, 100 mm with success. I grinded my Rails in staggered manner, few minutes grinding then few minutes rest (for cooling), when its head become quite hot, can't touch with fingers I stop and let it cool for some time.
Another thing to watch that don't take big bite i.e. don't dip grinder too much, which put a lot of strain on grinder. Tilt method works fine with small passes and since contact surface is less, it means less load on grinder. For final passes grinder disc may be run parallel to rails. For smooth movement little greasing on horizontal surface of rails (under verticle bolt) makes significant changes and smoothens the passes (as Gerald has said in some post). Also don't put lot of hand pressure on grinder. A uniform pressure is required for uniform result.
Although it takes more time, but it saves grinder and results are also good.
I learnt this from experience. If I am anywhere wrong, correct me.;)
Thanks.

Exactly, the cheapies die without pushing them...

Yeah, even cheapies work better if used right

I agree with Sharma, it requires more patience to get the good out of a cheapie!

but they do work, but if you are in a hurry - any but a few will burn away.

This one that died on me was not pushed hard at all. I set it up at an angle and took light cuts...just like I did with my old Bosch that is still running. The cut is so light that I grab the skate by the height adjusting bolt and pull it along...do about 2 passes and change it to the other side to do about 2 passes there before I drop it a little bit.

Well , may be bad luck! I once had a Chinese elcheapo run for almost 6 months used regularly for fabrication everyday which cost me 15USD (600INR).

some times you just lucky..... :) now I have a german AEC grinder, has been with me for a year now. No issues what so ever.

Dewalt makes 2 amp ratings in the small grinders, I used the larger one, I think it was about $100 at Lowe's. I burned up about 20 -4" blades on my x-rails, but is made nice cutts.

I found some 5-1/2" blades and used those to cutt my y-rails and thought at the time that larger blades would = less blade changes, that was a disaster. My y-rails were too uneven to use for rails, so I wound up having them cleaned up on a milling machine and used the hardened rails. I had to also have the bottom edge of the rails beveled for the inside radius of the angle. If I ever do any more rail grinding I will stick with the small stiff cutting wheels.

The larger diameter and/or thin blades will flex and make bad cutts even with minimal pressure.

Thought I would let others know that the wheel diameter and thickness will make a difference in the quality of your cutt.

As far as I know, Einhell is Asian in origin. The German sounding name is designed to mislead.

For cutting down the height with the thin disk, it is critical to make some very light cuts without flexing the disk at the beginning. Once the starter groove is established, then you can pile on the pressure.

I did exactly like this with thin disc and then before deep cutting I checked the cutting height with Jewellers lens at every few inches.

I couldn't agree more - I burned through the Ryobi router (a cheap brand here in the US) and then burned though another Milwaukee (a better brand) and finished with a final Milwaukee. Even with the trip to the store to exchange it, it only took me less than 2-2.5 hours to do all the rails. I'm sure had I nursed the Ryobi along I could have made it work but the time would have gone up dramatically.

In both cases IMHO the reason is same, hot machine.

David,

Which Milwaukee did you buy and did it fit the skate perfectly? You posted that somewhere (I thought) but I don't find it.

My wife says I can't find anything, though! :eek: