Here is a list of all the postings oldvelo has made in our forums. Click on a thread name to jump to the thread.
|Thread: SX2P Gas Strut Modification Issue?|
"As it stands, it’s just wrong to have the head forced up by default. It must be detrimental to accurate work - if you have a hand feed lever, you intuitively assume it’s limiting the tool position downwards. Currently, it’s basically moving the tool to its highest limit - all bets are off in terms of where it could end up in the workpiece".
"intuitively assume" are not terms consistent with precission engineering. To hold the head from being pulled into the job and elliminate the effect of the backlash is with a higher spring pressure to have the head held firmly UP at all times.
1 ) Backlash in an X2 is the clearance in the Rack and Pinion
2 ) The clearance in the Worm and Worm Wheel
3 ) End float on the worm to housing
4 ) Clearance on the Teeth on the Dog Clutch
5 ) Clearance on the Key and Keyway on the Pinion Shaft in The Dog Clutch
6 ) Two Universal Joints on the Worm Shaft Drive
All adds up to an excessive ammount of backlash. Around 3/4 of a full turn on my reasonably adjusted machine.
A lot of solutions quoted until you address this the problem will continue
( I’m not using modified tools, they are standard mills, drills or slot drills. I wouldn’t know how to modify them anyway)
Higher rated Air spring will give higher resistance to the cutter being dragged into the softer metals by the cutter edge angle and maintain pressure taking out any backlash.
The cutter can be modified with a Dremel grinder and back off the cutting edge to parallel to the Centre Line.
The gas strut needs enough power to push the head up to the top with with the fine feed disengaged and the lock slackened off.
Fit "Air Spring" to counter weight of mill head 24 kg rated is the one I have fitted to a much modified X2 mill.
If the castings you are spot facing is Çast Iron, Bronze, or Brass you need an end mill with the cutting edges backed off to 90deg to prevent the end mill from diving into the castings. The piddly little hand wheel is a pain to use the photo shows the mods done on X2 Mill Drill
|Thread: Cl300m Bearing and Belt Advice|
The toothed belt runs smoothly when tensioned correctly and should cause no problems.
The gibs on the top slide and crossslide may require some attention to get better performance to the finish.
One mod I have done is to replace the adjuster screws with cup point socket head grub screws and a 4mm ball bearing to look like this " <o> " Lock up the gibs tight then remove one and with a 4mm drill in an eggbeater hand drill tidy up the dimple in the gib strip. Put ball in and tighten up the grub screw then repeat with the next adjuster screw.
General opinion for bearing is to replace with angular contact ball bearings. These are the same dimensions as the original bearings.
The toothed belt on low speed will give positive drive. Vee Belts do not perform well at low speeds and high loads and tend to slip.
An option is to use poly vee belts "J" section 4 ribs or overkill with 6 ribs is adequate for 300 watt motor.
Simple enough to fabricate pulleys from Aluminium or Cast Iron Keep the diameters the same as the original or propotionally bigger that will still fit under the guards.
Poly Vee belts perform quite well at low speed compared to vee belts.
|Thread: Spindle Speed|
Pete says "Many good lathes fitted with variable speed have also been fitted with a tacho or speed readout." mine is only mediocre and has one fitted. Mill and Drilling machine share at the flick of a switch.
Variable speed power feed is also a good option. An Amp meter fitted to the main motor leads will help keep from overload when using a heavy cut.
Xd 351 points out the gap under the toolpost as the most probable cause. High speed steel ground for cast iron needs negative rake and the tip set not lower than centre hieght. Honing a high speed steel insert with an oil stone for better finish on almost all metals.
|Thread: Chester V20 Mill Drive Board Died|
please make sure that the controller is set up to match the motor. John will be able to help you with this task
|Thread: BSF and Whitworth "Across the flats " sizes.|
One size that defies the use of metric or AF substitute is 5/16 Whit Post war.
|Thread: Mini lathe blown fuses and Motor overheating|
Hi Apologies to all for wrong link
Keep us posted on your lathe motor repairs alway intrested in how thing get fixed.
Ouch! sound expensive. The use of the low speed recomended with the motor running at higher speed.
One improvement I have posted repeatedly is to fit a DC Ampmeter on the motor leads.
Mark the Guage with Motor Max Amps.and adust the cutting load to a reading of less the Motor Amperage.
Posted elsewhere Amp Meter
|Thread: Poor mans mill feed speed control|
An Ampmeter on the motor leads to monitor motor current to prevent overloading is a useful addition
|Thread: CL300M Mini Lathe Motor issues|
Try this Link for Electronic DC Controls A great library of mauals is available at the bottom of the KB's Page
I bought units and motors from Factory surplus spares sales for a fraction of the cost of new units.
Read and Enjoy Eric
I can speak from experience and with no connection to any company.
My workshop is powered by DC brush motors with American built AC to DC speed controllers form Dart, Minarik, KB Electronics.
With your background it will be no trouble for you to set up the controller to the motor.
Not the cheapest options available but reliable as to be able to set and forget.
|Thread: Ring rollers - anything known?|
The minimum diameter will depend on the material you wish to bend. Working in a jobbing shop we rolled everything from Armour Plate a total pig to anything less than 5 times the roll diameter to soft brass that was 1.25 the roll diameter was quite easy to achieve.
For up to 8 mm round stock you can use the spring makers method and wrap the on a mandrel in the lathe with snubber block in the toolpost.
|Thread: Twerps with hats on back to front and no front number plates|
Saw a while back a photo of a whole lot of cap on back to front brigade at a motor race meeting in late afternoon sunshine holding up a hand to shade their eyes. Explains a lot.
|Thread: Hot bearing?|
With My very limited knowledge is thatThe Myford Speed 10 has taper roller bearings.
Is the preload on the Taper Roller Bearings set correctly.
On a used machine with overheated bearings is most probably over greasing.
A quick dismantle of the of the rear bearing with the inner race removed, cleaned, inspected the inner race for any damage. Reassemble with fresh grease not more than 1/4 of the total bearing housing.
Reset the bearing preload after running and allowed to cool down to room temprature.
Afterthought edit! When a new bearing is fitted they will often run hot when run at high speed until they are "run in"
Edited By oldvelo on 15/08/2020 00:59:38
|Thread: World's Biggest Tractor in 1915 -- Aussie ingenuity at its best|
How this monster ever did any work at all other than downhill where the 45 tons would help it move.
The power to weight ratio on "Big Lizzie" is 1.3 hp per ton. Compared to the Fordson Model F first built 1917 that weighted in at just over 1 ton and rated at 20 hp.
Having the benefit of 20/20 vision in hindsight I offer nothing but respect for Ralph Falkiner.& Frank Bottrill for having an idea. Then have the courage to put into practice with this leviathen machine.
What little knowledge I have of the land that was developed for "Soldiers Settlements" was a government decission to utilise land that they had picked off a map with little or no knowledge of the true nature of the land or conditions in that area.
|Thread: Yet Another Mystery Object|
This does not happen often both Duncan and Dave are sort of right it depends on the liquid in the tank was it wine or beer. Had to consult Wikipedia for more information.
Based on this Dave is a beer drinker and Duncan a wine drinker.
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.
Click THIS LINK for full contact details.
For subscription issues please see THIS LINK.