7x Series Mini Lathe Backlash

(232,’2006-07-21 12:00:00′,’figNoggle’,’2006-12-20 08:04:55′,’david’,’7x Series Mini Lathe Backlash’,”,’This quick note is long overdue.

One of the major issues with the 7x series Sieg minilathes is that there’s backlash. In any variety whether it’s the 7×10 (the bed is too short if you plan on drilling and you can just about forget about reaming!) offered by Harbor Freight and ENCO or the 7×12 offered by Cummins, Grizzly, Northern Tool, Clarke and a host of others, or the 7×14 sold excusively by Micro-Mark (btw, get this one if you can spare the extra cash – the extra bed length is well worth the price differential alone!) , the cross slide has significant backlash.

One of the mods that is a must if CNC’ing it would be to address backlash in the stock brass nut under the cross slide. The quick and easy fix? Split the nut like we did with the X2 nuts.

Depending on how you intend to drive the 7x (via direct connection to the leadscrew on the handle end or via pulleys on the handle end or driving it from the exposed end of the screw), you’ll run into this problem and with our mini-lathe backlash at over 0.010″, this would be fine for woodworking, but for small steam engines or other projects where tighter tolerances are required (say, under 0.005″) it could mean an engine that doesn’t run.

That’s really the only downside of the 7x models. Other than that, it’s a great little machine!

‘,’

This quick note is long overdue.

One of the major issues with the 7x series Sieg minilathes is that there’s backlash. In any variety whether it’s the 7×10 (the bed is too short if you plan on drilling and you can just about forget about reaming!) offered by Harbor Freight and ENCO or the 7×12 offered by Cummins, Grizzly, Northern Tool, Clarke and a host of others, or the 7×14 sold excusively by Micro-Mark (btw, get this one if you can spare the extra cash – the extra bed length is well worth the price differential alone!) , the cross slide has significant backlash.

One of the mods that is a must if CNC’ing it would be to address backlash in the stock brass nut under the cross slide. The quick and easy fix? Split the nut like we did with the X2 nuts.

Depending on how you intend to drive the 7x (via direct connection to the leadscrew on the handle end or via pulleys on the handle end or driving it from the exposed end of the screw), you’ll run into this problem and with our mini-lathe backlash at over 0.010”, this would be fine for woodworking, but for small steam engines or other projects where tighter tolerances are required (say, under 0.005”) it could mean an engine that doesn’t run.

That’s really the only downside of the 7x models. Other than that, it’s a great little machine!

‘,”,”,”,’Sieg-7x107x127x14-Mini-Lathe’,”,0,”,0,4,1,1,’article’,”,”,’7x-series-mini-lathe-backlash’,”,”,”,”,”,”,”,”,”,”,’319b4f63b080f3ed86ac6b87c4471dab’,’2006-07-21′);

Setting Up Two Precision Screwless Vises Side-By-Side On The Mini-Mill Table

(256,’2006-10-25 12:00:00′,’figNoggle’,’2006-12-26 00:24:55′,’david’,’Setting Up Two Precision Screwless Vises Side-By-Side On The Mini-Mill Table’,”,’There are two frustrations that arise from using just one 3″ wide precision screwless vise: 1. with 6″ long parallels, you’ll find that they like to fall off the vise when you loosen the jaws and 2. milling, facing, or drilling longer workpieces sometimes creates problems if the workpiece extends too far out from the vise (facing yields poor results and drilling can sometimes push the workpiece down and tilt the piece or just cause undesired deflection).

What’s the solution? The real way would be to get a 6″ version of the same vise since something like the Kurt D-675 or like vises can’t be used effectively on the small mini-mill table. Since we haven’t been able to locate a wider version of the vise we currently use, it forced an alternate solution – buy another one of the 3″ variety (from ENCO – click here for ENCO free shipping coupons) and put it next to the other one.

First thing’s first – just because you buy the same SKU doesn’t mean they are dimensionally identical! guess how we found out? :)

Turned out that the newer model has narrower clamp channels and is .020″ higher on the base (eventhough the jaws are shorter).

We first had to make a middle clamp that would clamp down the facing channels of the two vises. We opted to use two bolts instead of one to add extra measures against moment-turning. Once it was made, we layed it out with the two vises. The important step here is to make sure you have enough clearance for the largest diameter tool with the vise to which you zero. For example, we always use the bottom right corner of the fixed jaw as our origin, so from there, we moved the table to its max such that a 2.5″ diameter face mill can clear it. (We’ll get a picture here sometime to illustrate this better). We set them side by side for a layout before the clamp-down and then mark the table for a general location marker.

Back to the dimension issue.. Since there was a .001″ shim stock roll laying around, we folded it up 20 times to create the right thickness and started mounting that vise first. We chose to square up the shorter one first. Either way is fine. After using our quick method of squaring up a vise in addition to using an indicator, we clamped down the first vise using just one side first. Then we inserted the middle clamp and then the other vise. Before tightening this one down, a tip is to chuck a pair of parallels into the first vise and use the fixed jaw of the second vise to make it in parallel alignment with the first. Then tighten down the second vise on the other side and you’re done!

No more parallels falling off and you’ve not only increased clamping width but also allowed for multiple part machining! Cool!’

‘,’

There are two frustrations that arise from using just one 3” wide precision screwless vise: 1. with 6” long parallels, you’ll find that they like to fall off the vise when you loosen the jaws and 2. milling, facing, or drilling longer workpieces sometimes creates problems if the workpiece extends too far out from the vise (facing yields poor results and drilling can sometimes push the workpiece down and tilt the piece or just cause undesired deflection).

What’s the solution? The real way would be to get a 6” version of the same vise since something like the Kurt D-675 or like vises can’t be used effectively on the small mini-mill table. Since we haven’t been able to locate a wider version of the vise we currently use, it forced an alternate solution – buy another one of the 3” variety (from ENCOclick here for ENCO free shipping coupons) and put it next to the other one.

First thing’s first – just because you buy the same SKU doesn’t mean they are dimensionally identical! guess how we found out? :)

Turned out that the newer model has narrower clamp channels and is .020” higher on the base (eventhough the jaws are shorter).

We first had to make a middle clamp that would clamp down the facing channels of the two vises. We opted to use two bolts instead of one to add extra measures against moment-turning. Once it was made, we layed it out with the two vises. The important step here is to make sure you have enough clearance for the largest diameter tool with the vise to which you zero. For example, we always use the bottom right corner of the fixed jaw as our origin, so from there, we moved the table to its max such that a 2.5” diameter face mill can clear it. (We’ll get a picture here sometime to illustrate this better). We set them side by side for a layout before the clamp-down and then mark the table for a general location marker.

Back to the dimension issue.. Since there was a .001” shim stock roll laying around, we folded it up 20 times to create the right thickness and started mounting that vise first. We chose to square up the shorter one first. Either way is fine. After using our quick method of squaring up a vise in addition to using an indicator, we clamped down the first vise using just one side first. Then we inserted the middle clamp and then the other vise. Before tightening this one down, a tip is to chuck a pair of parallels into the first vise and use the fixed jaw of the second vise to make it in parallel alignment with the first. Then tighten down the second vise on the other side and you’re done!

No more parallels falling off and you’ve not only increased clamping width but also allowed for multiple part machining! Cool!’

‘,’There are two frustrations that arise from using just one 3″ wide precision screwless vise: 1. with 6″ long parallels, you’ll find that they like to fall off the vise when you loosen the jaws and 2. milling, facing, or drilling longer workpieces sometimes creates problems if the workpiece extends too far out from the vise (facing yields poor results and drilling can sometimes push the workpiece down and tilt the piece or just cause undesired deflection).

What’s the solution? The real way would be to get a 6″ version of the same vise since something like the Kurt D-675 or like vises can’t be used effectively on the small mini-mill table. Since we haven’t been able to locate a wider version of the vise we currently use, it forced an alternate solution – buy another one of the 3″ variety (from ENCO – click here for ENCO free shipping coupons) and put it next to the other one.

‘,’

There are two frustrations that arise from using just one 3” wide precision screwless vise: 1. with 6” long parallels, you’ll find that they like to fall off the vise when you loosen the jaws and 2. milling, facing, or drilling longer workpieces sometimes creates problems if the workpiece extends too far out from the vise (facing yields poor results and drilling can sometimes push the workpiece down and tilt the piece or just cause undesired deflection).

What’s the solution? The real way would be to get a 6” version of the same vise since something like the Kurt D-675 or like vises can’t be used effectively on the small mini-mill table. Since we haven’t been able to locate a wider version of the vise we currently use, it forced an alternate solution – buy another one of the 3” variety (from ENCOclick here for ENCO free shipping coupons) and put it next to the other one.

‘,”,’Sieg-X2-Mini-Mill’,”,0,”,0,4,1,1,’article’,”,”,’setting-up-two-precision-screwless-vises-side-by-side-on-the-mini-mill-table’,”,”,”,”,”,”,”,”,”,”,’f6ca3ff06ff30fde1372f6394ceaf042′,’2006-10-25′);

KBMM/KBIC-125 DC Motor Controller and Homann Designs DigiSpeed-XL Cards

(255,’2006-10-25 12:00:00′,’figNoggle’,’2006-12-21 13:26:59′,’david’,’KBMM/KBIC-125 DC Motor Controller and Homann Designs DigiSpeed-XL Cards’,”,’We’re a bit late in posting this update…

A week back we received both the KBMM-125 (similar to KBIC-125) DC Speed Controller with their HP Resistor and Heatsink to bump capacity to 1.5HP instead of .75HP and the Homann Designs Digispeed-XL motor interface controller for Mach.

We’ve been busy working on a design of a 3-axis adjustable post mount for the Z-axis of the CNC mill, so these boards have been sitting on the table:

‘,’

We’re a bit late in posting this update…

A week back we received both the KBMM-125 (similar to KBIC-125) DC Speed Controller with their HP Resistor and Heatsink to bump capacity to 1.5HP instead of .75HP and the Homann Designs Digispeed-XL motor interface controller for Mach.

We’ve been busy working on a design of a 3-axis adjustable post mount for the Z-axis of the CNC mill, so these boards have been sitting on the table:

‘,’We’re a bit late in posting this update…

A week back we received both the KBMM-125 (similar to KBIC-125) DC Speed Controller with their HP Resistor and Heatsink to bump capacity to 1.5HP instead of .75HP and the Homann Designs Digispeed-XL motor interface controller for Mach.

We’ve been busy working on a design of a 3-axis adjustable post mount for the Z-axis of the CNC mill, so these boards have been sitting on the table:

‘,’

We’re a bit late in posting this update…

A week back we received both the KBMM-125 (similar to KBIC-125) DC Speed Controller with their HP Resistor and Heatsink to bump capacity to 1.5HP instead of .75HP and the Homann Designs Digispeed-XL motor interface controller for Mach.

We’ve been busy working on a design of a 3-axis adjustable post mount for the Z-axis of the CNC mill, so these boards have been sitting on the table:

‘,”,’Home-Brewed-CNC-Vertical-Mill’,”,0,”,0,4,1,1,’article’,”,”,’kbmmkbic-125-dc-motor-controller-and-homann-designs-digispeed-xl-cards’,”,”,”,”,”,”,”,”,”,”,’89fff36fd2515aa4df37bade33a66cdd’,’2006-10-25′);