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Gerald_D
Fri 26 May 2006, 02:31
The MechMate drawings will call for a machine shop with a milling machine to form the inverted V on the top edge of lengths of standard angle iron for the x and y rails. Pretty easy and economical - if you have access to a milling machine shop. But you may want to consider a variation on the following......

http://www.mechmate.com/Forum/messages/11/821.gif
Grinding in radial arm saw or table saw

Then a quick test in a table saw.....
http://www.mechmate.com/Forum/messages/11/822.jpg http://www.mechmate.com/Forum/messages/11/823.jpghttp://www.mechmate.com/Forum/messages/11/824.jpg

Don't try this if there is sawdust in your table-saw! http://www.mechmate.com/Forum/clipart/happy.gif

This is not the way that I had my rails made (they were milled), but I am just throwing this in here as food for thought.........

Evan Curtis
Tue 07 November 2006, 10:22
As you?re pushing the plate through and the grinding wheel is wearing down; how do you keep the edges parallel and square? Do you have to adjust the fence? Or is the wear on the wheel so minimal as to not matter?

Gerald_D
Tue 07 November 2006, 11:03
It was a thin "cut-off" wheel only 3mm thick. Not designed for feeding material from the side. And the grit is quite coarse and fairly loosely bound in the wheel. Unfortunately our table saw construction is such that a thicker blade/wheel doesn't go past the nose of the (left-hand) threaded shaft.

With the first couple of cuts, the wheel seemed to wear a lot because the cut was quickly getting lighter. Realise that all four edges are done with one setting (the plate is flipped over and end-for-end). Therefore 2 meters of edge per setting.

For the first couple of cuts I only lifted the wheel and didn't move the fence. When it got close to final shape I re-measured the wheel diam to do a final calibration. To my surprise, there was only 3mm lost on the diameter.

The last cuts were very light and all 4 flipped passes seemed consistent. The original edge was down to 1mm wide and looked absolutely consistent side-to-side and end-to-end. The fence was only moved twice, the wheel was raised less than ten times, therefore less than 10 passes per edge. (Had to do it during lunch-break when they allow me in the workshop)

Realise that I am not trying to get a 100% perfect slide by NASA standards. It must be an economic, wear-resistant, stiff slide suitable for a short-stroke z-axis on a router. Because this slide is harder and thicker than our SB's one, and because the wheel diameters are bigger, I will be able to pre-load the eccentrics quite a lot without causing excessive wear.

Evan Curtis
Tue 07 November 2006, 12:45
As I've thought about it and reading your process I see now how it could be quite accurate (more precise than SB's) If you scribe four layout lines one on each side along each edge then grind and file to the line, it might help in ensuring accuracy. The pictures you've posted look great. It appears you left a small (about 1.5mm) flat face along each edge there by ensuring the edges remain at least as parallel as the flat stock was when purchased. I'm going to have to rebuild one of my Z axis in the near future, now I have to decide between using a linear bearing slide as on the Original Mechmate and this V-Bearing slide. I really appreciate all you've shared with us.

Gerald_D
Tue 07 November 2006, 13:06
Evan, try it on some scrap flat bar stock first. I did the draw filing only to remove the right-angle marks left by the wheel. The amount removed by the file is very tiny and I wouldn't try to file to a scribed line. I don't even think the draw filing is necessary at all if the stone is finer. My draw filing started on the SB years back, and I regard it as my personal input - much like scraping bearings and beds (don't expect everyone to know what I'm talking about here http://www.mechmate.com/Forum/clipart/happy.gif hint (http://images.google.com/images?sourceid=navclient&ie=UTF-8&rls=GGLD%2CGGLD:2005-07%2CGGLD:en&q=bearing+scraping) )

John_H
Tue 07 November 2006, 15:43
Hi all,

I dont own a SB but I'm assuming this project
is a completely seperate machine all it's own?

I've built 5 small fixed bridge desktop sized
machines, But I'd like somthing a bit larger.

I'm interested in how you're working on the flat
bar. I'd be concerned that the fine grit will
do some damage to a table saw.

What about a piece of angle iron bolted upside
down alongside a cheap grinder. That provides
a 45 angle, then an adjustable block to provide
enough tension to slide the flat bar through
in several passes.

Here's a crude sketch...Hope it make sense.

John

http://www.mechmate.com/Forum/messages/11/1893.jpg

vadeem
Tue 07 November 2006, 18:49
I cut aluminum on the tablesaw without worry about damage all the time.

I always clean out ALL of the wood dust before starting. I also turn off my main dust collector and switch to just a plain shop-vac.

John_H
Tue 07 November 2006, 19:36
I also cut aluminum on mine. Mine is a 150.00
table saw. I imagine some of us use 5-6-7 hundred
dollar saws.

Relative to an aluminum shaving, the fine dust generated from an abrasive cut-off wheel (aluminum
or silicon oxide) WILL damage your motor bearings.
I know this from experience.

What I'm interested in is a way to create the necessary angles for bearings to ride on in an
on-demand, as needed fashion.

I believe a setup like I described may work very
well, accounting for a trial & error test or two.

I have seen some surface hardening compounds in a
can, but haven't tried any.

vadeem
Tue 07 November 2006, 21:49
Thanks for the tip before I runined my $$$ saw!

Gerald_D
Tue 07 November 2006, 23:00
http://www.mechmate.com/Forum/messages/1168/1887.jpg
http://www.mechmate.com/Forum/messages/1168/1888.jpg
http://www.mechmate.com/Forum/messages/1168/1889.jpg

The grinding in the table saw was surprisingly easy (20 minutes) A 175mm wheel protruding 26mm above the table surface gave the 2x45 degrees, albeit very slightly concave. Then some draw filing (http://images.google.com/images?as_q=draw+filing&svnum=10&hl=en&output=images&rls=GGLD%2CGGLD%3A2005-07%2CGGLD%3Aen&btnG=Google+Search&as_epq=&as_oq=&as_eq=drawer+cabinet+hanging+office+storage&imgsz=&as_filetype=&imgc=&as_sitesearch=&safe=off) with a fine file and a bit of emery stone (20 minutes). There is scope for refining this process, but already the results are an A-class "pass".

If I had to do a lot of these, I would use a thicker(wider face) stone of a finer grit, but the 3mm thin cutting disc (coarse) was not too bad. The biggest job was to make a centralising bush for the disc in the table-saw.

Can I suggest you guys try it with any old piece of flat bar before you believe me? http://www.mechmate.com/Forum/clipart/happy.gif

John_H
Tue 07 November 2006, 23:17
You wouldn't likely ruin it just doing it a few
times, but it's definitly Not Good for the motor
in the saw. This aluminum (or silicon) oxide
dust is harder than the bearings. and so small
that easily gets into places one can't see.

I'd do it on my cheap saw...it's on the way out
anyhow. But I'd hesitate on a nice expensive
shop saw.

Anyway, It'd be nice to be able to make up a section of rail, maybe several feet long, as it
was needed.

John

Gerald_D
Tue 07 November 2006, 23:20
The bearings on my grinders and table saw are identical in terms of seals - I can't see why grind dust will be a bigger issue for the table saw bearing instead of the grinder bearing. We are not talking of using the table-saw as a production 40 hour/week grinder - this is a quick light job. No worse than using a belt-sander near your table saw.

The biggest damage to the saw is caused by the burr that the grinding makes on the bottom edge of the rail. This burr scratches across the table. A bit of thin plywood under the rail will stop that.

John_H
Tue 07 November 2006, 23:45
I Absolutely Agree.

I would like to set up a small scale "production"
type of arrangement, just to see and test out how
well it'd work.

Here's what comes to mind. Imagine if this "V" track
were about as cheap as drill rod material, with
about the same tolerances. And the bearings were
well..not as expensive as they are now.

That combination would VERY useful to a lot of people. And there's really no good reason such
a combination doesn't exist. It's a big world full
of people trying to figure out what to make so they can survive, but strangely enough, nobody
makes what there's a demand for?

It can't be that hard to make a relativly straight
bar that is angled on the edges.

I'll throw away a $35.00 grinder if it fails.

What do you think of the grinder idea anyway?
I see you're the only one who's actually tried to do this.

John

John_H
Wed 08 November 2006, 00:12
I should have mentioned from the start that
I'm VERY impressed by the section you made
already. I haven't seen anyone else try this.

John

Gerald_D
Wed 08 November 2006, 00:18
John, in principle, your scheme is solid. Adjustment for progressively deeper cuts would be tricky.

Also, I would add a support edge for the back of the rail (bottom left corner in your diagram). Imagine what happens down there if you are putting 4 bevels on a flat bar.........

Little $35 grinders are often very under-powered - that isn't a problem if you have time. Taking lighter cuts will force you into a good finish. Also, the larger the stone the better - I don't know if $35 grinders can safely take bigger stones.

The experimenters must watch the legal speeds on stones, wear eye protection, maybe even gloves for that sharp burr...

For long lengths, one is going to need a long table to carry the weight - you don't want the rail to droop over a table, lifting the center section away from the wheel.

John_H
Wed 08 November 2006, 00:40
Well then a $100.00 grinder. I became Very
interested when I saw you'd actually done it.

If attention and care were put into a tool/jig intended to do only beveling edges, it may be worth the trouble. It could even be stepper driven very easily.

To try and do a "quick & dirty" on such an important part of the machine is no good.

I saw your part you'd made and that's what got
me going. I'm working on a Z-axis for my machine
as we speak and I wished I could use the "V"
bearings. PITA to get them though!

I gather you're the guy who's designing this
machine? E X C E L L E N T !

John

Gerald_D
Wed 08 November 2006, 01:43
What's stopping you from making your own V-rollers (http://www.mechmate.com/forums/showthread.php?t=20)? http://www.mechmate.com/Forum/clipart/happy.gif

John_H
Wed 08 November 2006, 02:17
I tried to figure out how to make the rails
first, and whether it was worth the trouble.

But to do it Precisely was going to require
a jig and I just sorta put it off.

When I saw your section the light came back on.

I'm sorry I haven't done my homework correctly here but if I understand it your project is a
stand-alone machine all it's own?

You're offering the plans alone and the end user
does the best he can.

You don't offer any parts.

I'm pretty sure I'm right with that but I will
ask directly.

I'd like to be a useful contribitor, that's why I ask. I think this may be one of the very best idea's I've seen.

I don't know about SB, but I've been rig-matizing
machines for many years and may be useful in some way.


BTW those are impressive too!

John

Gerald_D
Wed 08 November 2006, 02:47
"If attention and care were put into a tool/jig intended to do only beveling edges, it may be worth the trouble. It could even be stepper driven very easily." Apparently, that is how ShopBot make their rails. I've heard they use belt sanders instead of stone wheels, and they drive them down the rail with steppers. I guess that they control pressure and time in contact with the abrasive rather than the exact dimensions of the finished rail. Nothing really wrong with that, the exact dimensions of the rail are not critical - they just have to be consistent (parallel).

Yup, I am not supplying parts. I would really like to see guys like you standing up and offering parts to others in your area while I take a back seat. It would be nice to get a self-supporting community going.

fabrica
Wed 15 November 2006, 05:53
My machine operator has around two days of free time starting from tomorrow. I had a chat with him yesterday and he confidently said that he may be able to do the rails with the Shaper. But it is going to be a very tedious and time consuming job.I will keep you guys posted of the developments. In the mean time your suggestions on this issue are welcome before we start on the job (to make my life less miserable).

Gerald_D
Wed 15 November 2006, 06:16
Relax fabrica, go and watch some cricket! http://www.mechmate.com/Forum/clipart/happy.gif

I believe that your "shaper" and my "milling machine" are the same type of tool (different terminology in your country?). Just let your machinist do one rail first. Can you take photos for us?

Did you see how this thread (http://www.mechmate.com/forums/showthread.php?t=312) developed 2 days ago?

fabrica
Wed 15 November 2006, 06:31
In my country when our team is involved in a cricket match most of guys do not turn up for work (including me).

Definitly I will keep you guys posted with the photos on a regular basis.

fabrica
Fri 17 November 2006, 07:23
This is the sample V rail that we did with the existing shaper which ahas a stroke of 600 mm. We did this just to get some confidence. I will post a better picture tomorrow since I am still to learn the finer point of using the micro mode of my dig camera.

http://www.mechmate.com/Forum/messages/11/1972.jpg

fabrica
Fri 17 November 2006, 07:28
To do this rail we used a shaper which has a
600 mm stroke.

http://www.mechmate.com/Forum/messages/11/1976.jpg

fabrica
Fri 17 November 2006, 07:38
The rail came out fairly accurate and the dimensional accuracy was Ok. The hitch is the fact that we can only do 24" inches at a time. We cannot align the 24" pieces accuratly to get the final lenth. Tomorrow we will be trying out another method which will give us a continous run (around 11 feet)

We plant to fix a 1000 watt hand drill to the moving head of the shaper and mount the L iron on to the wise and move the bed horizontally to do the profile cut. The bed could move horizontally around 36" (motor Driven). Once bed comes to the end we would unlock the wise and push the L iron foward to do the next cut.

We are planning to use a end mill cutter mounted on the drill to get the 1" height cut then use a bevel cuuter to do the sides.

Your comments are most welcome.

Gerald_D
Fri 17 November 2006, 07:39
That is indeed a shaper and not a milling machine. It appears to be well-kept and your machinist must be proud of it. But, I don't believe you can make a rail longer than the 600mm stroke with this style of machine.

Oops, I posted too quickly - while you were typing.....

fabrica
Fri 17 November 2006, 07:52
WE are trying to get the bed to do the feeding and the drill mounted on the head to do the cutting by using end mill and bewell cutter. Looking foward to your comments.

Gerald_D
Fri 17 November 2006, 08:08
I am impressed with your enthusiasm and ingenuity for this project. For cutting the bevels, a 1000 Watt hand-drill should have enough power, but I am worried that you have to remove a lot of material to get to the 1" and that the hand-drill won't cope with that. Can you get very thin grind discs to cut off most of the edge of that rail?

Also, the vice will only carry a short length of rail inside its jaws, while you will be cutting a long path of 36". Most of your cut will be outside the vice and the rail will bend. Unless you put a strong/long support under the rail. I have the unfortunate feeling that you may be cutting a series of 36" long curves.

fabrica
Fri 17 November 2006, 08:20
No Gerald, I think you have got me wrong. We will be moving the bed not the Wise. The bed is holding the wise from underneath. The bed movement would be perpendicular to normal cutting head movenemt of the shaper. The wise would stick to the same position in the bed during the cutting process.

To cut the angle iron from 2.5" inches down to size (a little above 1") we would be using modified chop saw which will enable us to feed the angle iron parellel to the cutting disk of the chop saw.

fabrica
Fri 17 November 2006, 08:22
Sorry one more thing to mention. By using the chop saw we will cut the angle iron down to a size which is little above 1". The final cut would be done on the shaper with a end mill cutter.

Gerald_D
Fri 17 November 2006, 08:38
The bed will be moving. The vice is screwed to the bed (as per photo, but will be rotated 90 degrees). So the rail, bed, and vice move as a single unit....over a distance of 36". However, the vice is only about 12"(?) wide, and it will move completely past the cutter position. This is the part that worries me. If the vice was 36" wide then everything will be okay.. In your shaper picture there is a long plate lying in the bottom of the vice. The summary of my comment is that a similar long support will be good under the rail

The chopsaw is good. Don't be concerned about the rail curving after it is cut like this - it is flexible enough to bend back again when the screws hold it permanently in place on the MechMate.

fabrica
Fri 17 November 2006, 08:52
I got your point, our assumptions are wrong. The other option is to use the shaper in it's normal cutting direction. If this is so, we could do 24" inch pieces at a time and but join them together. When the rollers start to run on the rail, at the welded joints will it give a jerk to the gantry and spoil the show. If so, how are we to overcome this.

Greg Waggy
Fri 17 November 2006, 08:57
What you might do is put a some channel iron under the part you are cutting. Channel down.

fabrica
Fri 17 November 2006, 09:08
Greg thanks for your input. Can you please elaborate on what you were trying to suggest to me.

Greg Waggy
Fri 17 November 2006, 09:20
Well, where you can get the 36" cut and you are worried about curving, take a length of channel iron or aluminum and place it channel down for your angle iron to rest on. You can make it 4 feet long and that will give you support for 6 inches on either side of your 36" cut.

Gerald_D
Fri 17 November 2006, 09:23
Fabrica, I suggest that you test your original plan tomorrow, and see if the drill part works. If that is okay, you can concentrate to solve the vice problem....

Maybe take the vice right off, and put a long solid piece of material in its place. Using your end-mill, cut slightly into this long piece of material to get a nice reference bed. Then clamp/screw the rail to this bed....?

Similar to what Greg said.

Brian Backner
Fri 17 November 2006, 09:26
It is possible to accurately mill or grind very long pieces with even a small mill/shaper. You just have to set up an indexing reference:

http://www.mechmate.com/Forum/messages/11/1990.jpg

You first need to bolt, or otherwise clamp, a 1/2" thick steel straightedge along the back of the machine's table and exactly parallel to the longintudinal travel of that table - this is relatively easy to do by using a dial gauge chucked into the spindle.

Then it is a simple matter of setting the rail on the table, first clamping it to the straightedge and then clamping it to the table using step blocks and clamps. Then remove the clamps holding it to the straightedge and mill away with a 90 degree V cutter. Mill or grind 24" or whatever the travel of the table, unclamp, move 23", reclamp, mill/grind and repeat until the entire length is completed.

Depending on the mill/shaper you have, you could mill one entire side of the profile in one shot, or sneak up on the final dimension by gradually lowering the quill. If possible, I'd recommend the former unless you have an accurate Z-height readout or stop.

As accurate as a 12' bed grinder? No, but you should be able to come to within several thou, assuming that your mill is capable of that accuracy.

Brian

fabrica
Fri 17 November 2006, 09:29
I will keep your suggestions in mind and have a nother discussion with my machinist and decide on what best to do. In the mean time if anymore ideas come to your mind please let me know.

Greg Waggy
Fri 17 November 2006, 09:41
Right now I have a 4 axis controller I need to finish up and test. Then assemble that into my foam cutting machine. The old controller is unipolar and this one is bipolar. The controller I'll use for the new machine will be servo driven and I think I'll just buy the Gecko G320K drivers.

Gerald_D
Fri 17 November 2006, 10:30
Fabrica, during supper now I realised that your shaper probably does not have a continuous motor driven sideways movement of that table. I remember that shapers traditionally have a "clicker" (ratchet) drive from the movement of the main cutter slide. When the cutter moves forward, the table stands still, when the cutter slides back a linkage moves the table a little bit.

Your idea of joined rails is not that bad. Realise that you can place the joints so that only one wheel at a time crosses a joint. Only one wheel out of four.

Do you have a friend with a milling machine who owes you a favour? http://www.mechmate.com/Forum/clipart/wink.gif

fabrica
Fri 17 November 2006, 11:13
I could invest in a milling machine as a last resort. Tell me what do you have in mind. Allthough I have done a lot of favours to others I expect nothing in return. Maybe as you said my machine has a rachet drive. The machine manufacturer may be using only one main motor to drive all movements in the machine.

Finally I need a perfect machine. Since this is my first experiance with a CNC machine I need it to be a perfect one. I do not want to take too many risks.But still again I would love to to have a machine which has my blood running in it. In the process of building up this machine I would love to contribute some thing to this forum as well.You know what I mean ?

Gerald_D
Fri 17 November 2006, 12:07
You are making a lot bigger contribution to this forum than you realise. This forum is full of life and ideas mostly because of your questions. You are my inspiration (slave-driver!) to get all the drawings neatly published and the quantities correct.

A perfect machine is a process, not just a one time event. This is not a machine from a supplier - as you say, it is going to have your blood running it. You can continually modify, tune, improve, as you learn and get used to it.

You really don't need to invest in a milling machine for only producing a MechMate, but all-round it is a better investment than a shaper for general purpose work. Just to make some rails, I am sure that there is someone near you with a milling machine that can help you out. (Maybe your machinist knows somebody?)

Greg Waggy
Fri 17 November 2006, 12:42
I know one thing, I'm getting a lot out of this forum. As I start to build I'll take photos and share them with you. If you wanted to have top and bottom "V" rails how would you make sure the rollers hug the rails as tight as needed, springs?

Gerald_D
Fri 17 November 2006, 12:52
The spring tension on the motor pinions, against the racks directly under the V-rollers, hug the rollers against the rails on top. In the early days we did get the y-car to jump up off the rails.....when we drove the router into the table before switching it on, and other stupid things like that. Jumping off the rails can be regarded as a "safety valve" http://www.mechmate.com/Forum/clipart/happy.gif.

vadeem
Fri 17 November 2006, 14:00
To help stiffen up the rails, how about bolting them to the square tubing before grinding?

fabrica
Fri 17 November 2006, 19:54
Thanks For your compliments about my contributions to the forum. Ok assuming that I do get hold of a milling machine owner, what Do you have in mind?.

In this country the hardest part is finding a good milling operator not the investment part.

Greg Waggy
Fri 17 November 2006, 20:02
Gerald - Now that makes sense to me.

fabrica - That's why most of us hobby folks do it our selves.

Greg Waggy
Fri 17 November 2006, 20:05
vadeem - Just about anything square or channel can be used to stiffen the rail while milling. Just depends on what's available.

This is one great place to toss out ideas!

fabrica
Fri 17 November 2006, 20:41
We all waiting Gerald to wake up. Hope we do not have to wait that long. I am eager to get his ideas on a milling operation to do the rails.

Gerald_D
Fri 17 November 2006, 22:19
Good morning fabrica. Brian Backner's sketch above explains exactly what to do in a milling maching. You wanted to convert your shaper to a milling machine - I am simply suggesting to go to a real milling machine.

vadeem
Sat 18 November 2006, 22:29
I guess what I ment was to bolt the Angle iron onto the C-channel rails, then grind.

I would think that would "stiffen 'em up".

fabrica
Thu 23 November 2006, 07:55
Today I started on the V rails.

Below given is the picture of the Jig that I made to mount the Drill on the shaper head. The L iron was clamped directly on the bed of the shaper.

http://www.mechmate.com/Forum/messages/11/2030.jpg

fabrica
Thu 23 November 2006, 07:58
Below given are the pictures of the first cutting run that we did with the drill setup. WE intend to achieve the final result after a few more runs since we do not want to overlaod the drill too much.

http://www.mechmate.com/Forum/messages/11/2032.jpg

Gerald_D
Thu 23 November 2006, 08:13
Wonderful pictures! That mounting for the drill to the shaper looks professional and it is sign that you are going to succee.(Also the support under the point of the rail). Very impressed with what you (and your machinist of course) are doing!

Just for clarity in the bottom pic....
The regular, coarse marks are the sliced down rail, down to 1". Those are not chopsaw marks....you used the shaper didn't you? The 45 degree bevel is two passes?

fabrica
Thu 23 November 2006, 08:35
Gerald, This is a trial run that we did. We are never going to use this rail for our Mechmate. What We had a piece of 2 1/2" X 2 1/2" L iron in our workshop, one side we cut down to around 30 mm by using a flame cutter. Then we used the shaper to give a even height. Then we used the bevel milling cutter mounted on the drill to do the first cut.

We will be learning through our experiences and refining our process further before we do the final rail. Thanks for your compliments Gerald, but the credit should go to my machinist and the engineer. I only motivate them. But they really enjoy what they do. I should be able to upload some more photos tomorrow.

It is a long process. We are targeting to finish off everything within 20 machine hours (around 40 feet of V rails).

You could afford this luxury when you are born in a country where the machinists daily wage is around US 6.00 per 8 hour shift.

fabrica
Thu 23 November 2006, 08:41
If I am to reply to the final question in your last post.

Our intention is to first complete the two 45 deg bevel runs initially and do the 1 mm flat area in the final run with a flat end mill. Your comments and suggestions are welcome.

Gerald_D
Thu 23 November 2006, 09:09
If you are using an end mill for the 24mm flat height, I suggest you do that first, because it helps to indicate whether the two sides are even (parallel and centered). However, nothing touches that top face, and there is no reason to get it smooth or precise. Because you have the shaper, I suggest you cut all the rails to the 24mm height with the shaper.

Didn't you find that the flame-cut makes a bad distortion?

Our machinists probably get double that wage. Until they start their own companies and then get $200+ per day. (Our big MechMate is currently running 16 hours per day and earning $30/hr - that is a good machinist!)

fabrica
Thu 23 November 2006, 10:21
No gerald, you have got me wrong. To get the 24 mm height We are using the shaper. And to flatten out the top to 1 mm width, after the two bevel runs we use the end mill.

On the sample we did flame cutting and encountered the problem that you mentioned. I think I have two options available to overcome this problem.
The first is to make a jig for the chop saw and cut it or else to manually cut it by using hackshaw to around 26 mm heigh and the final cut could be done by using the shaper.

Gerald_D
Thu 23 November 2006, 11:00
This is the saw we use:


http://www.mechmate.com/Forum/messages/11/2034.jpg


Ours has another name on it, but it is identical to the photo above.

Normally it works horizontally to cut lengths of steel. (6" pipes max). And it does work surprisingly well. These bandsaws have replaced the old style power-hacksaw in most workshops.


http://www.mechmate.com/Forum/messages/11/2035.jpg



This style can also be used vertically:


http://www.mechmate.com/Forum/messages/11/2036.jpg


The vertcal use is a bit of a gimmick and I have only used it like this to cut the rails. You have to support the saw, otherwise you can push it over in this unbalanced position. It also is uncomfortable for a man to stand in front of it.

But, such a saw is a real asset to a metal workshop because they cut lengths of steel so well (in the horizontal position). Much cleaner, quieter and cheaper on blades than a chopsaw.

Greg Waggy
Thu 23 November 2006, 11:24
Geradl, My neighbor has one that is similar to the one sold by Harbor Freight and it does a nice job of cutting. Just about as good as a wood cutting bandsaw does.

Gerald_D
Thu 23 November 2006, 12:12
These Chinese made saws come in 2 sizes. The big size weighs over 300 lbs (first 2 pics above) while the small one in the last pic is under 150 lbs. I am suggesting the big one for the rails. (Harborfreight sells both sizes $200 vs $600).

fabrica
Fri 24 November 2006, 07:26
The sample cut of the V rail came out beautifully. Tomorrow we would start on the actual thing. The photo is not very clear. I will post a better photo tomorrow.

http://www.mechmate.com/Forum/messages/11/2045.jpg

Greg Waggy
Fri 24 November 2006, 07:57
Fab... It looks darn good to me! Now, how abotu those "V" bearings that will ride on the "V" rails? Got any of those made up or photos of the ones you are going to use?

fabrica
Fri 24 November 2006, 08:05
The V rollers would come from superior bearings. Hopefully they would be with me in another 10 days time. I hope to finish off the table by then.

Gerald_D
Fri 24 November 2006, 08:44
That rail looks 100%!

fabrica
Fri 24 November 2006, 10:07
Thanks Gerald, Tomorrow I would upload another photo which would give you better details of what I have done.

It would have been much more cost effective for me to have outsourced this job to another company. The main reason as to why I did it on my own, by utilising my own resources was due to the fact that I needed to contribute something worthwhile to this forum. I would love to see a lot of other guys contributing more frequently so the this becomes a very lively forum.