Work holding on horizontal mill

[Steve355Participant @steve355]

Hi guys

I recently had a need to cut a piece of mild steel into an L shape, to make a little square as part of a woodworking tool I’m making. The square needs to be very square, but not engineering, square squareness. So I cut the piece and then checked it carefully using my surface plate et cetera. It was way out. For what I’m doing, I would be happy with it being a thou or two out of square.

A problem with the Burke #4 mill is that the table has only one T slot. So to cut a straight edge on a piece of flat stock, you generally have to clamp it onto the table, and use a slitting saw off the edge of the table to cut the metal. The problem is, it’s extremely difficult to clamp it well enough to ensure that there is no movement whatsoever. I am 95% certain this is the source of my problem.

So today, I attached a little angle table I have to the main table I made a few little low profile clamps to hold the work better. I seem to get a much better result, and the cut was much more friendly too, with no sticking with the slitting saw, which is something that it has been prone to. See below a picture of what I’m trying to describe.

However, this isn’t really a solution because the little angle table isn’t really big enough to do many of the operations that I need to do (mainly cutting woodworking plane blades and making bits of tools).

so really, I need to get hold of a more useful T slot table with more slots, and bolt it to the single slot table on the mill. I have noticed on eBay that there are various extruded aluminium tables design for CNC purposes. Might this be a good way to go, to improve the general work holding capability of my mail? Or does anybody have a better idea?

 

[BazyleParticipant @bazyle]

I think you would be better off with a thickish ali plate that you put a key in the underside to align it to the slot, then a few thin slots, only 1/8″ on top for picking up alignment only and do the hold down with tapped holes.
Another alignment aid on the current table is a nice straight bar say 1 1/2 x 3/8 that has a couple of pins at each end to align it to the back edge of the table. Could even be worth drilling and tapping the table itself to hold it in place.

[Anonymous]

The correct answer is to get a bigger milling machine!

With the setup shown I’d dump the slitting saw, it isn’t rigid enough. Use a side and face cutter; if you look carefully they can be picked up for a tenner or so on Ebay. I’d also dump the angle plate; with the single axial clamp it isn’t going to be very rigid. One with a circular clamping face will be much more rigid.

Alternatively a box cube normally has 3 T-slots. One could mount the box cube with the slots vertical and mill the end of the vertical work with an end mill in the spindle, like a vertical mill on its side.

Andrew

 

[David George 1Participant @davidgeorge1]

Hi Steve you need a cube box clamping tool like this.

And also i think you can replace the arbour shaft to have a milling tool holder so you can use standard milling cutters. you can also clamp a small milling vice to the side or top of the cube to hold jobs.

David

 

[Steve355Participant @steve355]

Yes ideally I’d get another mill but that isn’t likely to happen in the short term.

I have a vertical mill for vertical milling (Dore Westbury) . What I’m trying to do is to cut through (usually O1) accurately and with low heat. Effectively using it like a table saw for metal. I’ve gone to a lot of trouble recently to get the Burke mill running nice and slow, and it cuts O1 very nicely. But as I said the really stupid thing about this mill is the single T slot.

I have tried a side and face cutter, problem is that those I have are too big or too wide. I thought about getting a slim ish one – say 1/8” or so. I will see what I can find on eBay.

I like the idea of the aluminium plate…. Essentially building a jig that would work for things I regularly do, with a load of threaded holes for clamps and locator pins, and some grooves to accommodate the cutter.

[Chris CrewParticipant @chriscrew66644]

When you say the slitting saw is sticking does this mean it stops rotating because it is not keyed to the arbor and jams in the work? Personally, I always use a key because any jamming of the cutter only scores the arbor plus you don’t have to overly tighten the end nut. Also, movement of the work can be prevented by placing a piece of light card or thickish paper between the work and the clamping surface. Any properly held work only needs the clamp bolts ‘nipped up’, it should never be necessary to heave on a spanner to make the workpiece hold.

[Steve355Participant @steve355]

That’s a really good idea re the card. The actual point of contact without that would be very small.

No, the slip occurs at one of the pulleys. I’ve played with the tension a lot to make sure that the motor doesn’t stall and the saw doesn’t spin on the arbor. I think what’s happening is the workpiece moves slightly and the saw catches. I think this is what’s happening because it occurs at points in the cut where one of the two usual clamps might pivot. When I put 4 clamps on today it had much better anchoring and I could pretty much plough through the whole cut with no or little sticking.

[MichaelRParticipant @michaelr]

Have you given any thought to putting extra T slots into the existing table you have a Dore Westbury which may be capable of doing the job.

[noel shelleyParticipant @noelshelley55608]

Michael R has beat me to it ! with the vertical mill put 2 more slots in the table ? Noel.

[IanTParticipant @iant]

My Atlas MF mill has only one T-slot Steve and the answer is very simple, just use a sub-table. I have several that bolt securely to the Atlas table and they have various slots cut or holes drilled & threaded into them, depending on what I need to do. The one shown is probably a bit thick but has been very useful to hold parts for various operations. Not sure what I was up to here but I have a saw abor fitted and often use end mills in horizontal mode to trim work…

A special ‘sub-table’ can also be used to adapt your mill table to other accessories such as vices and angle plates too – probably more useful when horizonal milling. Much simpler than changing your mill!  🙂

Regards,

 

IanT

 

[bernard towersParticipant @bernardtowers37738]

Doesn’t look like there’s room for more t slots in that table!!!

[Steve355Participant @steve355]

Ian – I’ve ordered a lump of aluminium for exactly that purpose. We’ll see how it goes!

 

cheers

Steve

[DiogenesParticipant @diogenes]

There’s a guy on Ebay with a ‘short’ (180×473) WM16 table for £30 – it’s in Abingdon..

https://www.ebay.co.uk/itm/204520346855

..it’s quite plain underneath, if you were lucky the shears would straddle your existing table / maybe with ‘adjustment’..?

 

 

[DMBParticipant @dmb]

I have a similar problem with my ‘Sharp’ mill with 2 t – slots in a 4  1/2″ wide table. Got round it with a steel sub – table, drilled and tapped for clamping studs where I wanted them positioned.

John

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