Member postings for KMP

John hi,

I have re-checked the more expensive belt I mentioned earlier and it is indeed T-Link, I had no slipping problems with that one at all and it did not have to be excessively tight to drive in either direction. I think my confidence at the time was low due to the problems with the cheap variety so I changed back. With several years more experience I will have no hessitation in using the correct section T-Link belt when I next need to change. Good luck.

Keith

John Hi,

Sorry to say that my experience is similar to Martin, I used both expensive and cheap link belts on my S7 to try and remove a clicking from the backgear gear assembly caused by wear in the locking pin. it did remove the noise but gave other issues which caused me to revert to the original belt in the end.

I found with the cheap type belt that they had to be extremely tight to provide a reliable drive. They also tended to stretch and needed links removing regularly in the first few weeks of running. In the end I was getting the belt as tight as I could with the countershaft in the drive position and then removing 1 or 2 links. This meant that the countershaft was under a good deal of load when running and I could see the bearings objecting if left like that for long.

The more expensive belt I have to say was very much better but still not perfect. It settled down fairly quickly and I only had to remove 1 link in the initial few days of use. I used it for several months without problem but when I eventually decided to adjust the spindle bearings I changed back to the vee belt which is still on the machine today. I just didn't feel confident with it and worried about the long term effects on the countershaft bearings and the pully profile, both reflectons of me rather than the belt I expect.

Another thing strikes me as you say your S7 has a poly vee primary drive, it must be a later model and I see that Myford list a different belt for later machines. It might be just the length difference on the big bore headstock but you might want to check that the pully profile is the same as the older type S7.

I guess my experience must be slightly different that the norm as many people seem happy with the link belts and expound the advantages with gusto. So perhaps my expensive belt wasn't the right type of expensive belt, i'm sorry to say that I cannot remember the actual maker but five years ago it was well over £25.

Best regards

Keith

Deric Hi,

I’m surprised that no one has answered yet as these are popular machines but perhaps you have had a private message with the information already. Hope I am not trying to teach granny. I expect you have already but, I have always found a phone call to Warco to talk with one of their engineers useful. They have always been helpful and know the machines they sell well.

I have just had a look at my unused Super Major and there is virtually no free movement as you describe, perhaps 10-15degs at the very most. Your machine is what is known as an RF40 clone and sold under many names and slightly different specs. The head is very similar to the larger RF45 which is a very popular conversion to CNC and a Google search for RF45 gearbox will find a number of sites that cover a gearbox re-build and repair. They do on occasion have gearbox bearing problems.

Is the backlash consistent? If you rotate the spindle a few turns to put the gears in a different position does it stay the same? Is it the same if you select a different gear ration? This will give you some clues to decide which shaft/gear cluster is to blame; unfortunately in either case a gearbox strip is needed.

You will find a good set of pictures of the similar RF45 gearbox here:

**LINK**

**LINK**

There is also a Yahoo group that covers Mill Drills that include the RF40 clones. They have a good PDF file in their file section that covers a gearbox strip and re-build. If you don’t want to register and download I can send you a copy if you let me have your email address.

I haven’t stripped one of these myself but they look fairly straightforward and the bearings are available from most bearing suppliers.

Hope this helps a little

Keith

Thanks guys, some good pragmatic advice there.

I guess I did sound a bit prescious but I was trying to indicate that the wear was there but not totally beyond scraping as an improvement. I was trying to see if this would be a "months work" or a "lifetime project". My main issue is that the necessary compromise to get full table movement leaves the centre part of the slideways rather too loose.

James, thank you for the pointer to Brian Caddy and I will contact him to get an idea of the possible cost. Rather unusually the Z axis ways on the base show some wear so that might make the task more expensive. All a compromise really as the machine shows its' age in other ways, it has in the past had the turcite treatment and the gib strips are now at the end of their adjustment even with a backing strip attached.

Anyway, thanks again as it allows me to put the problem in context and allows me to consider all aspects of the repair or replace decision.

Best regards

Keith

Hi all

I have a well used Bridgeport which is Ok when used in the centre portion of the table travel, however when the table is extended in either direction the table "tilts" with the ends rising or dropping about 0.002-3". Gib strips are set as tight as they can be. Obviously the slides are worn in the centre areas and need re-grinding or re-scraping. I feel that in this world of reasonable import mills the cost of a professional re-grind is not cost effective for my use of the machine.

So, how much work is it to manually re-scrape all the slides of a Bridgeport? Is it worthwhile or should I let the scrap man do his worst and buy something newer, less capable, not so well made but will still see me out? Any ideas, thoughts, or experiences you could offer would be very much appreciated.

Best regards

Keith

Hi Peter,

A common problem with these excellent little machines, see Lathes.co.uk on the Hobbymat page - last paragraph before the pictures. Simple steel block or "L" machined (filed) to match casting angle, in front of the broken one and thick enough (long enough L leg) to tap for a couple of bolts to attach through the hollow casting. Back this up with a strap inside the casting to spread the load. Many variations as already suggested.

While the original is a nice lightweight casting there is no reason why a steel block of less refined shape would not work much better when you have got the hang of milling. If you fancy trying for a spare try these people :

http://www.mattharvey.com/esselengineering/

They do stock some spares for the Hobbymat and you won't be the first person to ask.

As an aluminium casting it could certainly be welded with care and the right kit but I would still strengthen it with some type of strapping and be very careful with the adjusting screws. For more information on the Hobbymat, try this group:

http://groups.yahoo.com/group/Prazi_mill_lathe/

Regards

Keith

Mervyn, well done, first ME problem solved. There will of course be many more challenges along the way and may they all be sorted successfully as well. The fact that we all learn something new each day is what makes this hobby so absorbing and addictive. Look forward to seeing some of the things that you produce on the mill, they are much under-rated and I have found mine to be a very useful and reliable machine. Although I have a much bigger and newer one now I am reluctant to see the mill/drill go. If you haven't already give some consideration to putting some form of DRO on at least the two main axis, you won't believe how much easier it makes using the machine. Not all that expensive these days either.

Best regards

Keith

Mervyn

I have put a picture of the different version of the fine feed engagement in my photo album as I have no idea how to include pictures with a post.

Keith

Mervyn Hi

There was a version of that type of mill that had a setscrew above the fine feed spindle and to the rear of the coarse drill feed. The setscrew was in a curved slot that allowed the fine feed block to rotate and engage the gear on the end of the fine feed spindle with a spline cut into the coarse feed shaft. The set screw is released and the whole fine feed spindle moved up or down (can't remember which) while slightly rotating the coarse feed handle until you fell it engage. Tighen the set screw and you are away. There is also a version with a setscrew in the fine feed block with a straight slot to allow the fine feed handle to be moved forwards and backwards to engage. With these systems the three drill handles are always engaged so be careful when you disengage the fine feed if it is holding th espindle extended as the spindle will pull up and rotate the handle quickly, painful.

There is also a version that does not have a large knob in the middle of the coarse feed but had a threaded rod with a small lever with a round knob, these were prone to break and so were replaced by normal threaded bolts or setscrews.

A picture would help a lot in identifying which of these varients you have and what other names it was sold under.

Keith

Hi Mervyn

As Baldric has said the large black knob in the centre of the three arm drilling handle controls the fine feed. With the knob screwed out (anticlockwise) the two are disconnected. With the knob screwed in (clockwise) there is a taper which is seated and the fine feed knob will operate.

At that vintage the machine will be very similar to the Rong Fu 20/25 machine and the manuals are available to download and read as long as your chinglese is up to the task. There is also a good Yahoo Group that covers the Mill Drills and is well worth joining. The manual is available from the Micro Machine Shop web site just Google RF 20/25 Mill Manual and you will find it easily in PDF format.

Regards

Keith

PS I've had the Axminster version since 1984 - fine machine, have fun with it

Alf hi,

I bought an R8 Warco Super Major a few
months ago although have only just set it up and started to use it. My
experience with the company was first class, the machine was delivered with no
fuss at the arranged time; one additional item I ordered was incorrect but this
was changed within a few days at no cost to me. Everything works fine “out of
the box”, however one has to remember which part of the market you are in. The
machine is functional rather than pretty but nevertheless appears accurate and
very solidly built. All axis operate smoothly with minimal backlash. I am not
too impressed with the handwheels as they have some 3mm movement between the
locating sectors and seem to rely on the grub screw to provide the drive, not
ideal. The machine is quiet and smooth in all speeds but the table power feed
is a bit of a fiddle to set correctly. The mill cuts very well and within my
needs as a model engineer does not lack power. At the moment, only lubrication
has been required although I will readjust the gibs after a few more hours of
use as they settle in. While the headstock oil still appears like new I will
change it when I do the adjustments. The cover on the vertical dovetail is not,
I feel, likely to last very long but I guess time will tell.

Sometime in the future I will change the
motor for a 3 phase one with VFD to reduce the lowest speed a little.

There are a few things I would have done
differently of course as well as some that identify that it was not the most
expensive machine in the market. The scale that shows where the head is
positioned is akin to a wide steel rule screwed to the side, very vulnerable
and gets in the way of the Z axis locks. The handwheels I have mentioned and the
warning label on the side (wear gloves when cleaning as sharp edges may cause
injury) is very apt, I guess smoothing out the rough edges costs money and
doesn’t add to the functionality. These are very minor gripes however and all
in all I would recommend this type of machine to anyone who can handle the
weight and has the room. Mike has identified the weight of the head and he is
not kidding.

I had looked very hard at the 626/VMC type
machine which are very good value but in the end the limited table travel and
height below the spindle put me off. I also looked at the 836/WM20 type mill
and would have bought one if I could have justified that amount of money on a
hobby machine.

I spent time looking at these type of machines
with three major importers and had friendly and helpful advice from all of
them. The final decision was made on availability, work envelope, standard
equipment and total cost when delivery etc was included. This mill was bought
to replace a Bridgeport during a downsizing exercise so I am used to reasonable
machinery. Neither machine would hold a candle to the Huron and Ajax mills I
used in my youth. The total spend for machine, power feed and 3 axis DRO was
considerably less than a decent vice and rotary table would have cost for one
of those new.

Edited By KMP on 18/11/2011 21:50:56

Edited By KMP on 18/11/2011 21:52:39

I find this thread interesting as I am in the process of tearing down my own benches and machine stands of the past 15 years to allow some work in the roof. I’m no expert on bench design and no woodworker either so my experience may be somewhat “individual”. I have a mixture of benches, wood and metal frames and tops both homemade and bought in that have evolved over the years as I gained experience or had problems.

My assembly, gash or manual work bench, started life as a very solid (I thought) wooden framework of 4x2 and 4x4 legs glued and screwed with a ¾” plywood top braced by 3x2s. After a few years of hammering and banging, pulling and bending in the vice the thing wobbled about like a cork in water. The next bench was (and still is) a Dexion (angle iron with holes), braced frame, bolted to the concrete floor and rear wall with a 1” thick blockboard top covered in cheap hardboard which has been replaced several times. This bench has survived some serious abuse and is as stable as when built. I started with metal shelves under but the noise and tendency for things to bounce saw a change to thick chipboard floor panels braced with more Dexion to stop it sagging. When I rebuild this it will be the same construction.

The stand for my RF25 mill followed a similar development, initially wooden with 4x2” and 3x3” frames and 1” marine ply top, it was beautifully built by a friend (professional woodworker) and seemed totally solid. As my experience with the mill grew and I started to push its’ capability the stand proved very flexible and seemed to “spring” particularly under heavy or interrupted cuts. I replaced this with a simple welded steel box section stand of 50x50x2mm (sorry for the mixed measurements) uprights with 50x25x1mm horizontals and some 25x25x1mm bracing. The sides and back have 1mm steel sheet welded to the frame and this increased rigidity substantially. The top and shelves are 1mm steel with chipboard liners; the top is further braced with 50x50x6mm box section where the mill bolts through on typical leveling screws. While a little noisy until full of junk this has proven totally satisfactory with no signs of movement after the initial setup even with a much heavier mill.

I have had both success and frustrations with some of my “bought in” benches which I have to say were never the most expensive. I think it was Stan Bray who recommended in MEW a cheap (at the time) workbench available from Machine Mart. I bought one and put my Super 7 on it with some trepidation. While it has a thick solid wooden top, the uprights, sides and shelves are thin sheet steel bolted together with 6mm bolts and it looks very flimsy to me. I did add some angle iron bracing where the lathe bolts through. I know it shouldn’t work but it has, very successfully, with the exception of the one drawer which becomes difficult to open with more than two chucks in it. It will be replaced during the rebuild as it is really too deep for the Myford and space is becoming an issue. I can’t recommend the current offerings as they appear to have changed, the tops are certainly different and the steel appears even thinner but I have never measured it. I had planned to replace it with a genuine Myford stand but the lottery win has eluded me so it will be out with the welder again.

I also bought a woodworking bench from B&Q when we moved into the house 18 years ago, they were on offer at £25 each and stacked floor to ceiling. I often wish I had bought 6 of them, made from 4x2 glued and screwed together, including the top, it has been superb. The only issue is that over the years the top planks have moved and are as much as 6mm apart in places. When I reinstall this I will plane it flat and add an 18mm ply top.

So, I am now a fan of metal stands/benches for machine stands and where a vice is to be mounted. I add thick wooden tops which I find reduce the noise but bolt through to the steel frame where stability and rigidity are important. I also find that bolting to the floor or wall where possible adds greatly to the overall strength of the bench.

Regards

Keith