Gib surface?

[squelch]

Hello Gentlemen,

I'm very new to machining and a new 3-N-1 machine recently arrived. The handwheel to move the carriage was difficult to turn. While adjusting the gib on the back side of the carriage I noticed the face of the gib that rides against the rear way is pretty uneven and rough. I wouldn't consider it a machined surface. Since this rides against the way (a machined surface), I wondered if it needed some attention. My fear is that the uneven surface will wear grooves in the rear way.

Should the surface of the gib that rides along the way be smooth?

Thanks in advance!

- Squelch

 

[Daver]

Could the gib be in backwards?

How about a couple of pics?

 

[squelch]

Could the gib be in backwards?

How about a couple of pics?

I suppose anything is possible. Especially for a novice like myself. Here's a description of how I put it back into place. When viewed from the end, the gib is basically a parallelogram. The widest edges have to face either the way or inside edge of the saddle/carriage. Only one of the wide surfaces is machined smooth. That smooth surface also has four dimples in it that appear to line up with the gib adjustment screws. So, I assume that side faces outward toward the saddle/carriage. Leaving the rough surface riding along the way. I think if I flipped it over and put the smooth surface against the way the top edge would leave a V-shaped gap at the top; underneath the saddle/carriage.

I've read some posts (mostly on other sites) that suggest these import machines need some honing here and there. I wonder if this is one of those pieces they refer to.

I'll try to post some pics later this evening.

Thanks for your help!

- Squelch

 

[squelch]

I'll try to post some pics later this evening.

As promised here are photos showing each side of the gib in question. The first shows the machined surface with the dimples that align with the adjusting screws. The second shows the rougher surface that rides along the way.

- Squelch

 

[Tony Wells]

At times, that is done to reduce the actual surface contact area and hence the friction full contact would give. I would say that the gib would be softer material and would wear to a smooth surface before the machine way would wear into the grooved profile of the gib. Just jeep it oiled. Of course, it wouldn't hurt to hit it with something just to make sure it was straight. That would be more important to me.

 

[cnczone]

I found this http://www.cnczone.com/forums/benchtop_machines/170425-surface_finish_rf45.html

 

[Richard King]

That surface looks like someone forgot to glue a wear strip on it like Turcite. The surface should be smooth . Leaving that surface like that would be like rubbing 40 grit sand paper against the bed and it would be worn out in a shrt period. If it was made that way I would suggest you pull the rest of the machine apart and look at the ways. I have seen some lousy ways on those Chinese made 3 and 1 machines, but nothing that bad. Pull the tail-stock off and see what the bottom looks like. Is the machine new? Does it have a warrantee? If you can do some inspecting and take a few more pictures and put thm here and the name of the dealer you bought it from I would be happy to call them and help you get it resolved. Rich
Here is what a good scrape job looks like.

 

[squelch]

At times, that is done to reduce the actual surface contact area and hence the friction full contact would give. I would say that the gib would be softer material and would wear to a smooth surface before the machine way would wear into the grooved profile of the gib. Just jeep it oiled. Of course, it wouldn't hurt to hit it with something just to make sure it was straight. That would be more important to me.

Your point regarding surface contact makes sense. Especially after reading some other threads regarding the scraping of gibs and ways. However, I also think it's way beyond the minimum necessary and probably an artifact of an economical tool. The attention to detail just isn't there. There are two burrs that I'll also need to remove. Since I'd don't know the exact material composition I'll probably smooth it down some but, not worry about having it perfect (for right now).

Your point regarding the straitness may have some validity as well. It appears to have a slight crown. I'll have to put it on a plate and check it.

That surface looks like someone forgot to glue a wear strip on it like Turcite. The surface should be smooth . Leaving that surface like that would be like rubbing 40 grit sand paper against the bed and it would be worn out in a shrt period. If it was made that way I would suggest you pull the rest of the machine apart and look at the ways. I have seen some lousy ways on those Chinese made 3 and 1 machines, but nothing that bad. Pull the tail-stock off and see what the bottom looks like. Is the machine new? Does it have a warrantee? If you can do some inspecting and take a few more pictures and put thm here and the name of the dealer you bought it from I would be happy to call them and help you get it resolved. Rich
Here is what a good scrape job looks like.

Yeah, the wear between the two surfaces is a concern. The machine is new and under warranty. However, this is probably another example of you get what you pay for. I appreciate your generous offer! However, I think I'll tough it out until I can complete the one crude milling project on my list. After that, I'll follow your advice and spend some time disassembling, cleaning and truing the machine. Should be quite a project for a novice but good experience.

In the mean time, I'll knock of the burrs and hone the surface a bit until I have time for a proper job.

Thanks again for everyone's time!

- Squelch

 

[4GSR]

Squelch,

You may want to turn the gib over so the ground side, the side with the drill divots, is against the dovetail slide. Take a cordless drill with a drill bit and re-dimple places for the gib screws to seat against.

It looks to me, when the gib was assembled at the factory, the ground side was not put in against the dovetail slide. Then it was drilled dimpled on the wrong side.