Thursday, December 30, 2010

A2ZCNC Leadscrews Upgrade - Fabricating the Z-Axis Antibacklash Nut Mount Part 1

After fixing up the Touch Plate Probe yesterday night (see A little mishap), I completed the squaring of the aluminium block and laid out the required dimensions.  This little block will be fitted onto the Antibacklash Nut from A2Z so that the precision leadscrew can be mounted on the z-axis to complete the conversion.  With the little time I had, I've to stop right after I completed boring the 23mm hole where the nut slide in to fit.

As usual, pics were taken along the way.  Here they are:

Started with drilling progressively bigger hole after center drilling. My boring tool needs a minimum hole size of 1/4" to start.  Being Singaporean (Kia Su syndrome), I gave it a 7mm.

The HSS boring tool in use.  Here you can see the layout lines and the circular mark on the surface caused by the shank of the tool rubbing against it.  The boring bar is a little short for the 25mm thick block.

Completed the "boring" operation.  The marking are almost gone... This is an inexperience machinist wannabe at work.

Test fitting the antibacklash nut. Can't insert it all the way yet as I couldn't bore all the way through the stock due to the cutting depth of the tool being a little short.  But the fit is rather good.
The back of the mount.  I didn't take pics of how I managed to mill out the portion left behind.  Deburring tool was used to remove the balance material.

Good fit.  I marked the 2 screw hole locations again using the digital height gauge.  They're right in the middle of the 2 mounting holes on the antibacklash nut.  I feel so proud of myself...

The entire process of boring out the 23mm diameter hole started with some fear of the stock moving out of the chuck.  The cut wasn't smooth at the beginning but I managed.  Spindle speed was rather slow to reduce vibration as the hole is not in the middle of the rectangular block.  As the length of the boring tool is less than the required depth of 25mm, I left a few mm at the back of the stock for cleaning up later.  Once I get the diameter of 23mm, I adjusted the tool angle to clean up what I can of the balance.  The rest was left for the deburring tool.


This is the same type of deburring tool I used for the final cleaning up. Mine has a blue and longer handle.

I hope to complete the nut mount by the next session, if time permits.  And if the A2Z horse shoe Stepper Motor Mount can be used, I'll have one less component to make to complete this mod.

When the precision leadscrew conversion is done, I'll move on to wire the spindle to the Gecko G540 VFD so that I can control the spindle rpm using gcode.  Then I'll have full automation (almost) at home :-)

Almost 1am now.  Better get some sleep.  Some appointments lined up tomorrow.

Wednesday, December 29, 2010

A little mishap

I've been using erniebro's touch plate micro (on cnczone.com) to zero the cutter before starting a job on the mill. It is really a time saver; no more jogging in small little steps of 0.01mm to zero by sight of all the 3 axes.

On Christmas night, it stopped working. Touching the 2 crocodile clips together (my "probes") didn't lit up the Touch Test LED in the Probe section. Couldn't figure out what happened after checking around for a while. So went back to manual zero'ing to complete the facing job to prepare the stock for the z axis mounting adapter for the A2Z leadscrew.

I kept thinking about what could have happened for the past 2 days and decided to check for connectivity of all the wires leading to the probes. Using a multimeter set to continuity mode, I probed the DB9 cable, the DB9 breakout board, and the wires connected to the crocodile clips. All perfect, nothing broken. Then I started connecting them part by part while testing continuity after each part was assembled. No problem found. Strange...

I decided to open up the controller box and look at what I've found:


The little wire (blackish one across the 4 pins on top) came loose from its soldering joint.
The 4 pins on the top row at the back of the DB9 socket is soldered together with a piece of hard wire. The black wire you see in the pic is the ground.

I took out my trusty made in China soldering iron to try to heat up the hard wire to melt the solder underneath it so that they'll stick.  Instead, the black wire came off the slot.  Couldn't seem to heat up the hard wire enough for the solder to stick.  Quite some time was spent trying to remove the solder from the slot using a soldering pump and trimming of the black wire to fit the slot.  Gave up using the hard wire.  A piece of jumper wire was stripped, laid across the 4 pins, and the joints soldered.  Ran some test before closing the cover to make sure it works.



Jumper wire soldered in place and excess trimmed off.

Now I'm back in business!

I've done some further work on the A2Z leadscrew hardware for the z axis.  Will try to post them up tonight if I've the time.

Saturday, December 18, 2010

A2ZCNC Leadscrews Upgrade - X & Y Axis Installation

We just returned from HK Disney, reaching home at about 2am this morning.  We were supposed to reach Singapore yesterday afternoon at about 5pm but due to some technical problem with the aircraft, the flight back was delayed for 6.5hrs.  Other than being too cold for most of us, the trip was a good one, especially for the kids.

Spent some time in the shop this afternoon trying to fix up the precision leadscrews for both the x and y axes.  The process was simple enough except for the smaller hole size on the Super Gibs for the fastening wire.  Had to enlarge the holes slightly.  Some play observed on x but let's see if its serious enough after some trial cuts.

As usual, some pics.

Table, saddle, and motor mount were stripped off and the base cleaned.


Placing the new saddle on the base to mark out the new Super Gib.

Sawing off the excess on both ends.

The holes provided are too small for the stock wire.

Enlarging the hole a little.

Another problem encountered: the hole for the wire came too shallow.  It was drilled a little deeper.

As the new leadscrews are much bigger than the stock, adapters are provided to rise the motor mounts on both x & y.

Both screws mounted. I didn't take pics of the installation of the antilash nuts on the leadscrews and the table as I was very frustrated with fixing up the wire and the gibs.

Some videos of tests done:

Moving saddle by hand to see if the gib is set too tight. You can see the cut I have on my middle finger. This was from trying to fix up the cable to stream video from my iPhone to the roof mount LCD player in my car.



Motion test:



Simple backlash test:



I'll be doing more test to see if the play on the x axis would create some problem.

Monday, December 13, 2010

A2ZCNC Leadscrews upgrade - The Shipment

Just when I thought I could only receive the shipment after my trip to Hong Kong, it arrived in my office today morning.  Took the chance to swing by to pick it up while going to 313 in Orchard Road with the family and mother-in-law.  The well packed box was sitting on my desk awaiting my arrival.



Well padded. No loose parts moving around in the box during the ride back.
After peeling off a thick layer of "onion skin", here lie the contends

The tubes are for the precision leadscrews.  I'm impressed! The screws I bought from Sherline were merely wrapped in brown papers.  Guess the price paid made the difference.

The rest of the parts out of their boxes.  The tube on the lower right is the Way-Oil.  The Gibs were said to perform better than the stock ones.  Both recommended by Tim of A2Z.

Anti-lash Nuts.  Spring loaded to take up backlash.  Some parts look a little worn.  They may be just tear-out, inflicted during testing.  Hope they work fine.

3 views of the saddle.  Look SOLID.  The blue colored strips are of the same material as the ones on the Gibs.




The adapter for the stepper motor mounts.  3 were provided of which 1 was given free of charge.  May not be using it on the Z-axis as that may require me to change the dimensions of the mounting driving the Z-axis saddle.  The plans were downloaded from Graham of Sherline Group.

I'll be leaving the country for the next 4 days starting tomorrow.  Hope to have sometime during the coming Saturday to install the precision leadscrews on the X and Y axis.  Z will have to wait as the backlash nut mount has to be fabricated first.  I'll be away again next Monday and Tuesday.  So little time yet so much to do.....

Tuesday, December 7, 2010

New Tools

I've been shopping online recently.  Including the outlay for the coming holiday, I'm over budget. But... I'm happy :)

Three of the five shipments came in last week, while I'm away in Melaka, Malaysia.  Took some photos to show off here.  The fourth shipment, by far the most expensive of the lot, is on its way.  Hope it reaches me before I take off to Hong Kong for my family holiday and at the same time, to pick up my fifth purchase.

So, what did I buy exactly?

ER16 Adapter with 3/4-16 threads. This is from Carter Tools.  Good support and prompt replies.  Very pleasant experience dealing with Carter despite the low priced item.

Precision Tooling Plate from High Tech Systems. Mounting holes and the slots at the back need deburring. Derick has also been prompt with his support.
Deburring the mounting holes with a countersink bit. No many holes.  So not so bad.
ER32 (per review on CarterTools.com) collet chuck from Beall Tool Company.  Ordered as a set with some imperial collets with a set of nice looking brass hinges for a good friend of mine.  Not much of a service to talk about as only one of my questions was answered.  Couldn't tell me if its really an ER32.
Front view with a collet mounted.  Look at its size relative to the lathe spindle.  It is mounted on the lathe with the 3/4-16 threads.  Have not tested the run-out.  Maybe after my holiday.
The fourth shipment contains the precision leadscrew upgrade for all my axes on the mill.  Tim of A2ZCNC has been rather helpful with my questions.  The order includes the 3 leadscrews, 3 anti-lash nuts, a saddle, and 3 gibs which Tim said are more superior than the stock gibs from Sherline.  Bought a bottle of #2 Way Oil which was said to be a better lube for the moving parts.

From the installation manual I downloaded, X and Y upgrade look simple enough.  Z requires some modification to make it work.  Tim was kind enough to throw in the adapter to offset the stepper motor mount to fit the new leadscrew.  I'll need to fabricate the mounting required to move the axis.  Plans and photos are downloaded from Graham of Sherline Group.  Hi Graham, thanks for the idea and plans!

The last purchase will be picked up from CTC Tools' office in Shatin, Hong Kong.  This will be my 3rd purchase from Haine.  This round 19 pieces of ER32 collets (metric) from 2mm to 20mm, a 2nd digital dial indicator (1" travel) to make my very own tramming tool from Bogstandard (John) build log on Madmodder.net, and a set of inside/outside radius gauge (1mm to 6.5mm radius).

Come to think about it, I've been buying but have not been building much things.  Need to have that in my new year resolution; to build more stuff and cut down on spending (though I enjoy buying... good form of stress release).

That's all for now, little one needs her milk and daddy is going to make her a bottle...

Sunday, November 28, 2010

3D Milling of a human face

I've been wanting to do this for a while after my first failed attempt. Though I've not been into my shop for quite a few weeks, some time was spent on my notebook applying different features to the 3D head forwarded to me by jrmach of Bobcad forum.  The object is not to mill out the whole head, which I do not have the necessary knowledge at this point to use the 4th axis correctly.  It is to have a go with just the face.  The decision is to only mill out the 1st 10mm from the tip of the nose to experiment with the different features provided for in BobCadCam.  The Z-Level Rough was use to remove bulk of the material (wood this time for ease and speed of the job) followed by Slice Planar.  Cut amount in Slice Planar was set to 0.2mm to try to capture as much details as possible but I'm not able to match up with a smaller diameter cutter; A 6mm ballnose was used with 3mm radius.  Roughing was done with a 1/2" endmill.

Some pics:

Roughing out with 1/2" endmill


After finishing off with the 6mm ballnose

Short video showing the 6mm ballnose at work:



I notice during the milling process that the spindle was almost at the end of the Z travel. It was scaringly close.  Thank God that I decided to go only for 10mm from the surface (z = 0).  Can't imagine what will happen to my mill if I went for 15mm...  I've ordered a precision toolplate with cam type fasteners from Hightech Systems.  This will raise up the work by the thickness of the plate.  From the vpost tracking, it has arrived in Singapore yesterday and should be delivered to me on Monday.

A short video of that:


I also ordered an ER32 holder, some collets, and an ER16 (3/4-16) adapter with this shipment.  Hope these are the last I bought for the hobby this year.

Sunday, November 7, 2010

8-Direction Vertical Milling Column Upgrade - Done!!!

Little time in the shop resulted in no updates for the past weeks.  With the market slowing, I don't know why I'm still so busy.

The column upgrade was finally completed with slight modification to the length of the leadscrew.  As mentioned in my previous post, rotating the circular clamping disk didn't allow the vise to clear the disk.  I bought the column spacer to provide the clearance required.  But the spindle is lifted so high that it couldn't get down low enough to do any useful work.

This seems to be the max the spindle can go down to.

I saw that the leadscrew's end was "tucked" inside the clamping disk and realized that I need to shorten the screw a little.  So out came the Proxxon vise.


Sawing off a short section of the leadscrew.

A little too short but its working fine

Tramming came next.  Roughly getting into position:



Using DTI to get the column square to X and Y axes:

The rectangular piece is the Proxxon parallel

Best I can do for this

After tramming, I tried to "flycut" with an endmill held in the ER16 collet.  The result was good as I can get to 2 decimal places accuracy (in mm).  I've never gotten so close.  Rather happy with the result of this upgrade.  The 8 direction column makes tramming much easier than my previous setup.  Should have bought the 2010 mill right at the onset.

Further milling revealed that I may have a problem with my mill slipping out of the ER16 collet during cut.  I changed to an endmill holder and the problem went away.  Need to solve this as the ER16 way of holding tools is the most convenient to me.  Anyone with suggestions please share.

Sunday, October 10, 2010

8-Direction Vertical Milling Column Upgrade

Finally found some time to install the new vertical column.  Collected it few days back from Mike but simply couldn't find time to do it.

I layout the parts on the kitchen floor the night I brought it home to visualize the installation.  Found some dings on the column top to my disappointment.  These are unlikely caused by rough handling during shipping as the packing was done rather well with few plastic cushions and newspaper holding the parts.

The dings on the column top at 3 spots.

Swing Arm Assembly. Notice the chipped edge...
Anyway, don't think that will affect the performance of the parts though I did't expect to see such from brand names like Sherline's.

The installation went smoothly as the Swing Arm came assembled.  This save quite a bit of limited shop time.

Installation completed.
 A vise was placed on the table to check if it clears the bottom of the table.  It didn't.

The Matchling vise is of the same height as the Sherline's screwless vise.
I removed the column bed from the clamping disk and found that the 4 screw holes holding the bed can be rotated 180 degree giving a better clearance.

Rotating the clamping disk works but...

The clamping disk is now the obstacle...
The objective of purchasing the SGD400++ 8-direction column is to do away with the A2Z spacer block for rigidity while still able to make full use of the long base.  It seems that I may need to buy the column spacer to lift the clamping disk out of the way.

My next project will be the Simple Ocillating Steam Engine.  I downloaded the plans from Steve's Workshop (http://www.steves-workshop.co.uk/index.htm).  Steve is a wonderful guy.  I wrote to him with some newbie'ish questions on the materials, reamers, the BA standards etc.  He really took the time to explain to me what I need to know to get started.  At this moment, I'm collecting materials and tools in between appointments.  Hope to get started soon.

Thursday, September 30, 2010

Job Done!!! Finally...

I wrote the previous time that I was tasked to do 6 pieces of a bottle shaped part in aluminium.  Robin, who tasked the job to me, told me that they're pesdestals to mount model ship to a base.

Managed to find time tonight to complete the balance 3 pieces.  It was a struggle and a race against time as I'll be involved in some events at night for the next 2 days and will be doing full day showflat on Saturday.  Thank God that out of the 5 pieces of round stocks I bought, only one ended in the scrap bin waiting to be recycled.

From the exercise, I started to have a feel on how zeroing is done.  The only thing left not solved is the answer to the parts being undersized.  I've a feeling that it is due to backlash on the leadscrews.  Though the job has ended, I'll be doing one test when I've the time - to increase the distant the tool retracts so that backlash is taken up before moving back to the cut.  I'll post my result here.

Not many pics taken this session as the focus was to get the job done within the session.


6 pieces of aluminium stock 25.4mm in diameter and 60mm in length.  Bought them at Kelantan Lane for $2 each.

The stocks were flycut on the mill. I went for the same setup previously with a piece of vee block clamped in the vise.  This is much faster than facing the ends on the lathe.

Couldn't figure out why this happened.

 All done!  Hope the less the 0.2mm in height will not affect Robin's use.

7 pieces of stocks for 6 pieces of work.  The bigger piece in the centre was the 40mm piece bought for making the die holder.  Quite a waste to use it for this job but I ran out of material when I first started this job...