X2 belt drive conversion

[spuddevans]

So I decided to make a start on my X2 mini mill belt-drive conversion. I'm using the popular plans available on the Yahoo mini-mill group, but I'm not sticking rigidly to them.

I plan to make the base and motor bracket out of some 4" wide, 0.5" thick ali.

I started today by taking some 3" ali bar and hacksawing off a 50mm chunk.


Boy were my arms tired, took me about 15mins, I really need to get a bandsaw.

I then chucked it in my 4jaw. This presented me with a potential problem, probably all you experienced machinests knew this already, but when I hacksawed the chunk off and checked both cut ends with a square, and of course the ends were not square. Now normally with smaller chunks of metal I would mount it in the chuck and when tightening up the jaws will get the part squared up parellel to the ways. But with this size of part I am using the jaws reversed and they dont have as much gripping depth and when I chucked it up it did not tighten up into square and parallel. 

So this was my crude solution,


2 squares, one mounted on a 3-2-1 block on the ways, and one on the part, adjust it square, rotate 90 degrees and repeat, then re-check on all angles and then finally tighten up, face one side and then I was able to reverse the part and hold it tight up against the jaws, mount the dti and get the part centralised, and then face the other end.


Then it was just straight turning to reduce it down to start forming the Big Pulley as per plans.



It's amazing just how much swarf you can make with this, I got a big boxfull from just this operation.

Next I will be boring out the bore  and then reversing the part and turning the pulley-shaped-sections, and then on to the smaller pulley for the motor.

One thing I do need help to find is a supplier of the 1/4" V-belts themselves, I've had a bit of a look online with no success, but maybe it'd be better going into a local belts & bearings supplier and getting one there. 


Anyway, that's all I got for today.


Tim

[Brass_Machine]

...

One thing I do need help to find is a supplier of the 1/4" V-belts themselves, I've had a bit of a look online with no success, but maybe it'd be better going into a local belts & bearings supplier and getting one there. 

...

If you don't have any luck, let me know. Mcmaster carr is 10 min from me. I can get em and ship them to you.

Eric

[Darren]

My local motor factors in the UK seem to stock every size I have ever asked for over the years. They are stored by type and length there unlike Halfords which you need to specify which car you want it for.

[Bernd]

So this was my crude solution,


Tim

Tim,

Nothing crude about the way you solve a problem. Most ingenious way to do it.

Good luck with the rest of the project.

Bernd

Edited to add: Now that I've studied the pics a bit more I see that it really won't matter if it wasn't perfectly square since you will be turning the surface down quite a bit.

[CrewCab]

Nice start Tim 

The belt for my conversion is a Gates Truflex 0130 (interchanges with a 2L130), don't know if yours will use the the same.  The size is 1/4" x 13" (6mm x 330mm) though I found it hard to source them here, in the States they are readily available so Brass Machine shipped me some over.

Looking forward to following your build.

CC

[raynerd]

Tim, great start - excellent photo`s, please keep them coming. I am really keen to see all the stages to make this project so keep the pictures flowing if you can bothered to keep taking them. I`m really interested to see how you actually cut the pully sections, tooling used and such.

Regarding belts - I will eventually need some, be it in 5 months or 18months and therefore for the price, if you find a supplier or decide to get some shipped over I`d be happy to order a few + spares and split postage and import costs.

Chris

[CrewCab]

LIMCT in the States sells the 0130 Belt as "cheap as chips" ................ (about £1.50), but their carriage costs to the UK were unreal  ................. however .............  having a few members over there that needn't be a problem.

CC

[bogstandard]

Have any of you considered using Redthane belting, just buy yourself a length and cut and weld it to fit. No more searching to find a specialist stockist of your v-belts.

I find it much better than normal V belts and it lasts considerably longer. Machines run a lot quieter with less vibration, and in bad circumstances can have enough 'give' in it to prevent damage to the machine, and of course, during it's life, because it is always in tension, no belt tension adjustment is needed.

http://www.poly-products.co.uk/beltext.htm

It comes in a variety of sizes and you can usually buy it by the metre from local engineering suppliers. I will be upgrading my lathe belts soon, and that will allow me to switch pulleys without having to make a complicated tensioning device. Just stretch it off one pulley and onto the next.

John

[spuddevans]

If you don't have any luck, let me know. Mcmaster carr is 10 min from me. I can get em and ship them to you.
Eric

Thanks Eric, if I cant source any here I might just take you up on that  

My local motor factors in the UK seem to stock every size I have ever asked for over the years. They are stored by type and length there unlike Halfords which you need to specify which car you want it for.

I'll give that a try Darren, I think there's a place near me that specialises in just belts and bearings so I'll try there and then some motor factors.

Now that I've studied the pics a bit more I see that it really won't matter if it wasn't perfectly square since you will be turning the surface down quite a bit.

I know that I've cut away a lot on one end of the ali bar, but the plans call for a pulley of a little over 3", and this is a 3" bar so I didnt want to loose any more than absolutely nessesary as I will already be making a slightly smaller pulley than the plans call for. Thus the extra effort to make sure everything was properly square and true.

Nice start Tim

Thanks CC

don't know if yours will use the the same.

Yup, it's the same, although as I'm making the major-diameter pulley a little smaller than the plans call for I might get both a 13" and a 12" or 12.5" as well to be covered.

Tim, great start - excellent photo`s, please keep them coming. I am really keen to see all the stages to make this project so keep the pictures flowing if you can bothered to keep taking them. I`m really interested to see how you actually cut the pully sections, tooling used and such.

Regarding belts - I will eventually need some, be it in 5 months or 18months and therefore for the price, if you find a supplier or decide to get some shipped over I`d be happy to order a few + spares and split postage and import costs.

Chris

Thanks Chris, I'll keep on taking pics, even of the really mundane stuff   I'm intending to cut the pulley sections with my parting tool, I figure on turning down the center flat sections of both pulleys and then angling the compound over and cutting the V sides. If anyones got any other ways of doing it I'm all ears.

Re the belts, PM recieved and replied to.

Have any of you considered using Redthane belting, just buy yourself a length and cut and weld it to fit. No more searching to find a specialist stockist of your v-belts.

I find it much better than normal V belts and it lasts considerably longer. Machines run a lot quieter with less vibration, and in bad circumstances can have enough 'give' in it to prevent damage to the machine, and of course, during it's life, because it is always in tension, no belt tension adjustment is needed.

That looks very interesting, is it easy to weld? Does it need a different pulley groove from a V-belt?

Hmmm  I'll have to look into sourcing some of that around here or online.


Thanks everybody for looking and commenting.


Tim

[Darren]

I need a new belt on my mill, the inner is starting to come away and no doubt causing some vibration.

Would you recommend that type of belting for such a machine John?

[TFL45]

Great pics as usual, Tim. 

Here's another belt option, although I haven't tried it myself.  Appears to only come in 1/2" size, so might not be suitable for your application, but others might have use for it. One source in Canada is Lee Valley  ( http://www.leevalley.com/home.aspx ) but must be other vendors.

Floyd

[bogstandard]

As I said Darren, I have used it in industry, and now I am about to fit it to my lathe.

Floyd has also shown the link belting, which again is very good.

It is fairly expensive, but in my mind, well worth it.

I always used to keep a few metres in my shop (when it came to me as freebies), but I only have short lengths left now, after modifying all my previous machines (and other peoples) with it.

If you can wait a while, when I get what is required for mine, I will do a little write up on how easy it is to get a strong welded joint that should last the lifetime of the belt.


John

[spuddevans]

Ok, do you ever have one of those days that everything seems to go not-so-good, and takes 3 times as long? Well I've just had one of those days.

I started out by center-drilling the bore.



I then drilled it with a 1/4" drill, then 3/8" and then 1/2" ( the biggest drill I have, I really must some bigger drills as it's a lot quicker to bore with a drill than to bore with a boring bar ) and then set up with a boring bar with enough sticking out to reach through to the other side of the Pulley blank.



Then things stopped going smoothly. I had bored out the bore until it was 1mm under-size, and decided to try my hand at cutting the key-way. Not having done this kind of thing before I ground up a Hss blank to be the right size for the key. I ground a shallow angle kinda like a woodchisel (and this may well be the error of my ways).

When trying to cut the keyway I found that the pressure would rotate the QC-toolpost, digging the tool in harder and causing progress to stop. So I thought that I could perhaps dig out most of the keyway-waste-material on the mill with a 6mm (the smallest cutter I have) mill.


But I still had the same problem of the tool digging in and rotating the toolpost holder. I tried to tighten the toolpost holder up but only succeeded in breaking off the handle on the toolpost 

So in frustration (and not thinking that it would be better to just pause and perhaps take a break ) I decided to make 3 cuts using a hacksaw (now now, I may be a bit daft, but I can still hear your laughing  ) to get rid of most of the waste.



It was at this point I decided to leave that particular part of this project as if I kept at it much more I might have had to retrieve the pulley from next door's back yard. Thinking about it now, if I cant get to grips with cutting the key-way on the lathe I might do as someone has suggested in the plans, and use the spacer-collar already fitted to the mill and just bore out the pulley to be a good press fit with some loctite.


Finally some sense raised its head ( I dunno where it was prior to this  ) and I decided to remount the pulley the other way round in the 4jaw, center it, and then turned the OD's of the 2 pulley sections.



I then tried to set my compound to make the cuts for the inner sides of the V parts of the pulleys, and came across a flaw in my lathe. My C2 has those nifty little DRO's incorporated into the compound and cross slides, these sit a little proud and prevent you from setting the compound to any angle greater than 45degrees, and as the plans call for 71Degrees ( total of 38 degrees from edge to edge of the V, so splitting that gives me 19 degrees of 90, if you follow what I mean, but please correct me if I'm wrong)

So without modifying the lathe I think I'll have to grind up a Hss toolblank to 19 degrees to form the tapered V, unless any one of you experienced machinests can give me a better way of doing this?


So that's as far as I got today, now I'm (virtually) off to find out what I can about cutting key-ways. Nothing like bolting the door after the horse has locked  errm, or something like that 



Tim

[Darren]

Hi Tim,

I did something similar here, not sure it's going to help you much though.

It sounds like you need your tool post to be tightened down a bit more?

http://madmodder.net/index.php?topic=460.msg1410#msg1410

[spuddevans]

Hi Tim,

I did something similar here, not sure it's going to help you much though.

It sounds like you need your tool post to be tightened down a bit more?

http://madmodder.net/index.php?topic=460.msg1410#msg1410

Actually that helps a bit, just seeing what your toolbit is shaped like, that might be where I was going wrong. I may try again with a re-ground hss bit.

Thanks for that link.

If anyone else has a diagram of how to grind the proper tip for cutting an internal keyway please feel free to share it, I really could use all the guidence available on this.

Tim

[sbwhart]

Tim

Your doing the right thing in cutting out some of the meat, to take some of the load off your small lathe, Try shaping the key out in small sections and you can always finish it off with a file, noting wrong in that its what our Grandfathers would have done.

Good Luck

Stew

[raynerd]

Hey Tim, as I said, I`m one step behind you, I wouldn`t know how to start without your post.

It is really interesting as I showed the plans to my mate earlier this evening who does machining on a much bigger scale and he was immediately drawn and curious as to how the key way was cut. Following darrens linked post to his "one off key groove" - I can see how he has turned the parting tool on its side but I don`t understand how the groove is being cut? I take it the work piece is not rotating the in the jaws, but if it isn`t, how is the tool cutting?

Chris

[John Stevenson]

You rack it backwards and forwards with the carriage, a bit of a poor mans shaper.

JS.

[spuddevans]

Hey Tim, as I said, I`m one step behind you, I wouldn`t know how to start without your post.

It is really interesting as I showed the plans to my mate earlier this evening who does machining on a much bigger scale and he was immediately drawn and curious as to how the key way was cut. Following darrens linked post to his "one off key groove" - I can see how he has turned the parting tool on its side but I don`t understand how the groove is being cut? I take it the work piece is not rotating the in the jaws, but if it isn`t, how is the tool cutting?

Chris

The lathe is stationary, the groove is (supposed) to be cut by the tool taking a tiny cut each pass. You know if you have a tool in the lathe and even when stationary you wind it past the workpiece it can leave a tiny groove if the tool's too close? It's the same principle with cutting a keyway.

I'll have another try tomorrow and take some pics of my efforts.


Tim

[raynerd]

Ohh, I see. So you are simply scraping metal off. Interesting.

[raynerd]

Hope you don`t mind me posting a pic, not trying to hijack your thread 

I`ve just bored the piece to size, and taken down the diameter to form the pully section and I suppose the shaft area. Don`t know where to go from here.... pully sections? I couldn`t have done it without your pics and your post....I really appreciate it, cheers



Chris

[spuddevans]

Hope you don`t mind me posting a pic, not trying to hijack your thread 

Feel free to add whatever you want, or even start a build thread yourself 

I`ve just bored the piece to size, and taken down the diameter to form the pully section and I suppose the shaft area. Don`t know where to go from here.... pully sections?

The next step that I did was to get the outer sections of the two V pulleys to size. Then there's the dreaded key-way (or is it key-set?) and the shaping of the inside of the V sections.

Those are my next steps.

Tim

[spuddevans]

So I started today by working on the keyway (ok people, start your screaming  ) I re-ground the Hss bit to be more the profile of a parting tool on it's side. This worked a bit better than previously but I found a bit more success with using a file gripped in the QC toolpost


To make things a bit easier, I released the saddle so it would slide by hand rather than by winding the handle back and forth, and then just pushed the saddle to and fro while advancing the cross-slide by about 0.10-0.25mm each time.


I then turned to the V parts of the pulley, as mentioned before I couldn't set my  compound to the required angle, I decided to grind up a form tool, and here it is.



After grinding the bit up I found out that I had accidently ground it up to the exact size needed for the V-belt.  ( I had thought that I would plunge it in and then move the bit sideways to get the size needed)  The only thing I would do different if I did again would be to use a 5/16" Hss tool blank instead of a 3/8" as it was a bit tight cutting the 2nd (the smaller one). I used the larger size of toolbit to try to reduce chatter.

So I very gently and slowly inched (or should that be millimetered  ) the tool into the workpiece. I started off in the higher gear but the chatter kept kicking in the safety overload detector thingy in the C2 and it kept cutting the power, so I used the lower gear. The tool produced a lot of fine shavings.



And after that I repositioned and did the same again and ended up with this,





And that's as far as I got today, next I gotta start on the smaller pulley.

I may have to deepen the keyway a bit as well.


Tim

[sbwhart]

Well done that man.

 

Nothing wrong with methods that work   

Cheers

Stew

[Darren]

That's a neat idea with the file...looking good there Tim