7' X 4' Combi

[Ricardoco]

Firstly Jazz and i must say this at the begining and not the end, I dont want replies that are skirting round what im after, for fear of offending me, Im a grown man and i dont have time to waste, I like the direct responces and if i factor in a bit of northern sence of humour, i get a free grin to boot!!!

I also respect all those people who know better than me and dont see the comments as a personal dig, If i cannot do something because i lack Knowlege, experience, or indeed a little common sence, then its nice to know that there are those that will give replies i wont forget in a hurry LOL and i get their wisdom for FREE.

Hi Rick,

See Little things but important and worth the little extra effort.!

First the linear rails and bearing pockets. Ideally you want registers to aid alignment/re-assembly and because your pocketing the bearings you can use the walls of these pockets has the registers by making sure the bearings on one side of each set of bearings aliagn with the walls (See Red circles in pics)Also I'm sure this you know but I'll point out any way just in case.? The pockets have square corners and we can't easily machine sq corners. So the pockets will need additional length to allow for the radius of the cutter. (circled Blue)

I have made the pockets for the bearings 70 X 48 with a bearing size of 65 X 46, the rails are 15 x 15 and the pockets for them are 16mm where applicable. if you think that needs changing let me know, its easy to change, and i have allowed enough space in the design for this

Can I just ask what's the rectangular piece with 2 holes.? (circled green)

LOL i did wonder if anyone would ask and i didnt factor in the radiused corners in the back plate for it, I was going to tig that in to the back plate as a mount for the lower bearings for the back plate and the Y ballnut.

The top stepper bracket.? Is it a 2 piece part or single.? Doesn't really need to be 2 piece and could be single and still do the job. Also the little bits that lock into the pockets won't be needed and make the machining and fit harder than needs to be Again due to radius corners clashing with square edges.)

I had wanted it to be a single part, pocket locks gone!!

To be honest all the pockets and step down on top piece could also be done away with and reduce machine time without adding a massive amount of weight. Lot of work in that one piece that doesn't need or had much to the machine..)

Gone!!

The I'd also leave a small skin 1-2mm on the lightening pockets on rear plate so it doesn't leave access for flying chips...)

Done!

I know it's just probably to save drawing but remember all internal corners will have radius so take care this doesn't catch you out if anything is close on dimensions or catching.?

Yes it was to save drawing but i'm glad you have mentioned it, I will go over the design as i dont want any surprises as just the material will cost a mint so i dont want any surprises, Im determined to get this right.

Edit: Oh Before those observing think I'm being negative or putting someones work down which to be honest I'm getting sick being accused off then Ric asked me to have a look and comment.

How much more negative would it be not to mention things, and watch me struggle when you could clearly have helped.

This is a free forum and if i get a bit of banter, well thats a small price to pay!! (and im free to give it back)

So many people read emotion into text that isnt there, I dont want you to stop being critical of any designs i submit, it will save me finding out the hard way..

Cheers Jazz

Updated designs will be submitted shortly..

Rick

[mocha]

snip...

i dont have time to waste, I like the direct responces and if i factor in a bit of northern sence of humour, i get a free grin to boot!!!

I also respect all those people who know better than me and dont see the comments as a personal dig, If i cannot do something because i lack Knowlege, experience, or indeed a little common sence, then its nice to know that there are those that will give replies i wont forget in a hurry LOL and i get their wisdom for FREE.


snip...

How much more negative would it be not to mention things, and watch me struggle when you could clearly have helped.

This is a free forum and if i get a bit of banter, well thats a small price to pay!! (and im free to give it back)

So many people read emotion into text that isnt there, I dont want you to stop being critical of any designs i submit, it will save me finding out the hard way..

Rick

+1 to that Rick. To me that is the best thing about all the people here who take the time and trouble to contribute. I'm not interested in fluffy platitudes, I'm interested in getting it right.

[JAZZCNC]

I have made the pockets for the bearings 70 X 48 with a bearing size of 65 X 46, the rails are 15 x 15 and the pockets for them are 16mm where applicable. if you think that needs changing let me know, its easy to change, and i have allowed enough space in the design for this

All it needs is at one side of each set of bearings to have the side of the pocket line up with the edge of the bearing, so the bearing or rail Butt's upto it.
So IE: On the Z axis have say the left bearings align with the pocket edges, same with rails on Left side. With the Y axis have the upper Bearings align with upper pocket edges, the rails you'll have to deal with on the Gantry but same applies a straight and true Register helps.
The rest of the pockets can be any size so long has the bearings and rails fit inside and infact a bit of wiggle room helps.

LOL i did wonder if anyone would ask and i didnt factor in the radiused corners in the back plate for it, I was going to tig that in to the back plate as a mount for the lower bearings for the back plate and the Y ballnut.

Ye thats what I feared.!! Don't do that it's too inflexible.! "Adjustment" "Adjustment" "Adjustment" is the secret to the whole machine and Esp the setting up of the Z axis and ball-screw alignments.
Ask anyone who's done it the difference between working and locking up is silly small and if you haven't got easy or multiple ways to adjust then life will be frustrating.!!

[wilfy]

if only everyone could read jazz's comments in the same way!

[Swarfing]

Nothing wrong with being load and proud. With the input you are getting Ric will turn out a very nice build. Rome was built together and not by one man (plus a huge amount of slaves)

[m.marino]

Rick,

With that ballnut a good bit of the issue with lubrication is mute BUT still make sure you have access. I also see why you want to keep in near completely enclosed as that nut does not have protective flanges for the ball races. Therefore the less chance for swarf to get in the better.

Speaking from experience of a a design done with Jazz and he built for me and I have worked on a good bit and have had to lube and put shims back and all the fun that goes with it, listen to Jazz. Now hear is where I get to make a point a bit clearer. Lubrication is not just the ball nut. Those linear rail carriages are going to want a greasing once a quarter if you are using that machine with a daily use level (that is even with the protective scrapers).

Personally for myself I am setting up a bit of over kill as I am designing a lube system for my current machine that will be a lube block for X, one for Y and most of Z and a single lube point out the front of the Z plate with a cap for the ball nut.

Registers made setting up my machine take two days instead of a week ( even though it came up here in two heavy large sections it still needed squaring, truing and tramming. A side note to folks, tramming is something you should check once a fortnight to once a month (depending on how heavy your use is and what your cutting). My source for this information is a few friends back in the states that are having fun laughing at me stumbling along and learning (They are both 20 yr plus machinists and High School "friends" ).

You have a really nice design and with just a bit of adjustment it will not only do you proud as a finished build (ha, a machine is never finished), but the quality you put in and care to detail in the build has a direct result on the out come you get. I mean heck with the power supply I finally built and installed for my machine I am running acceleration level in scary land with rather nice rapids. When I get the feeds and speeds right (which is getting more often) I am getting wonderful finishes. Keep it up, doing good.

Michael

[Ricardoco]

Rick,

With that ballnut a good bit of the issue with lubrication is mute BUT still make sure you have access. I also see why you want to keep in near completely enclosed as that nut does not have protective flanges for the ball races. Therefore the less chance for swarf to get in the better.

Speaking from experience of a a design done with Jazz and he built for me and I have worked on a good bit and have had to lube and put shims back and all the fun that goes with it, listen to Jazz. Now hear is where I get to make a point a bit clearer. Lubrication is not just the ball nut. Those linear rail carriages are going to want a greasing once a quarter if you are using that machine with a daily use level (that is even with the protective scrapers).

Personally for myself I am setting up a bit of over kill as I am designing a lube system for my current machine that will be a lube block for X, one for Y and most of Z and a single lube point out the front of the Z plate with a cap for the ball nut.

Registers made setting up my machine take two days instead of a week ( even though it came up here in two heavy large sections it still needed squaring, truing and tramming. A side note to folks, tramming is something you should check once a fortnight to once a month (depending on how heavy your use is and what your cutting). My source for this information is a few friends back in the states that are having fun laughing at me stumbling along and learning (They are both 20 yr plus machinists and High School "friends" ).

You have a really nice design and with just a bit of adjustment it will not only do you proud as a finished build (ha, a machine is never finished), but the quality you put in and care to detail in the build has a direct result on the out come you get. I mean heck with the power supply I finally built and installed for my machine I am running acceleration level in scary land with rather nice rapids. When I get the feeds and speeds right (which is getting more often) I am getting wonderful finishes. Keep it up, doing good.

Michael

Cheers Michael, that ballnut as you say has no flanges, but that too is being worked on he (wink), worst case is I have to open up the channel by 6mm each side and fit a conventional or threaded ballnut, and I may go that way in the end purely for simplicity of duplication and security of the balls!!. I too am toying with the lube question, My Boxford has a lube system that looks after things and I'm thinking of fitting tubing directly to the bearing blocks, although for the moment I will be drilling lube ports in the plate and have left enough room to access the nipples that are fitted to the bearing blocks, the orientation of the blocks when fitted will allow them to be lubed without too much fuss, the bottom ones from underneath when the z is fully up and top when the Z is fully down. The Y axis will be accessible by lining up with holes that will be in the gantry itself, they will be covered when not in use. From Friday I will be tinkering with the design to take account of the Registers. Out comes the Vernier again!! LOL but its so worth getting it right.. Rick

[Ricardoco]

Ok this does have a bearing on the design so please be patient with me, If you were machining these Z parts what would your Cutter preferences be and why, this will help me when i finalise the design, so please everybody pipe in, Remember What type and Why please, if you prefer then PM me as i know some of you wizards like to keep your advantage secret, but please let me know. Right off to bed now 4 hrs should do LOL speak after 1..

[JAZZCNC]

Depends on what you want and if your lazy.?

Could get away with doing the whole lot with 6mm and no tool changes but would take longer due having to keep shallower depth of cut for 6mm cutter with 30mm plus flute length.?

Or could use 10mm that would allow to hog the whole lot away quickly with deeper DOC and just have larger radius in the corners.

Or if really need tight corners use combination of both 6 & 10mm. Use large cutter to Hog the 98% material away then run round twice with 6mm. One profile pass to fettle corners then another full depth to clean up.

If the radius doesn't matter, which in your case don't think it does then I'd use 8 or 10mm has they will allow more DOC and speed up the Job with no tool changes. . . 8mm would be my preference.!

[Jonathan]

I'd use 8mm 2fl to cut the pockets, do finishing passes on the pockets with 6mm 1fl if required and cut the part out with 6mm. So basically the same as Jazz.