Thread: Crazy idea ..or not ?

just thinking about that. your oun mill might be a better way to cutt thess slots. they will just put it on a mill any way. so if you set the table. up to run square to the cutting spindle .Oor say for example one of the other slots. just get the right size woodruff cutter and slot drill and away you go.

Does the table on your mill travel the full extent of the slots under the cutter???
If it does save yourself some big money and do it yourself, Thats why you have a mill isn't it??? To save paying someone else.
Just think of the extra tooling you can buy with the dough you woulda given a machine shop..
Just my 2c worth.
Matt

Or perhaps do something like this

Mill Fixture Plate

it is on my "todo" list.

Yeah gang . Great minds think alike . I did think of milling the slots in myself, ' in situ ' so to speak . It wouldn't be a great loss if they don't reach right to the end of the table . A larger machine in a engineering business would do it the whole length , but as you say , it may cost heaps . I will investigate this and think about it . The slots in it now are 14mm by the look of it . Even if the teo added ones are 12mm , it's better than the present setup . Fred, I also did think of the fixture plate as a option . Could be expensive to buy one as it needs to be a precision finish on it . I noticed our friend Harold H uses cheap $15 drill vices for his milling machine . He modifies them somewhat but he says they work fine . He is of the opinion the vices are rarely needed . Instead, he used T nuts and various jigs and packing pieces to hold work down . Mike

Looking at Fred's pictures it wont leave much meat in the table.
https://www.woodworkforums.com/f65/new-dm45-mill-129991/

If you do go through with doing it, you maybe able to take off one end cap to let the table come in more so it can be done by you instead of elsewhere. Then when you get to half way replace that end cap and take off the other.
Doing it on the machine will make it perfectly accurate and wont cost you an arm and leg.

Personally I would work with what you have and leave the table. Machining it may relieve some stresses in the table and bow it. 12mm T slots on 35mm centres doesn't leave much.

I can understand your frustration as my HM52 has 5 and I couldn't imagine not having them. The Grizzly model of mine only comes with 3 T slots as well, not sure why.

Dave

If the slots didn't reach to the end, how would you slide your T nuts in?

I agree that the 3 slots can be a bit limiting at first, but with a bit of imagination and fiddling I have been able to mount everything I wanted so far. I agree with Dave re "meat", I would be reluctant to take that much out of my table.

The only thing I don't like is mounting my 6" Vertex Rotary Table, which is one of the reasons I am thinking about a tooling plate. But I may just make up a plate the width of the base of the RT that spans the the 3 slots, then drill holes in it to mount the RT on. Then leave the plate permanently on the RT.

I have made a fair few T nuts over and above the ones in my clamp set and purchased quite a few different length M12 hex and socket head bolts, these give me a fair bit of flexibility.

I agree that Harold H has some very nifty ideas for clamps etc and I have copied most of his articles in MEW and scanned the relevant pages in his books, I will slowly make most of them.

Just to give you an idea, I just went down and measured mine and they are 14mm T slots on 44mm centres and there is 18-20mm between the bottom of one T slot to the other.

Dave

Originally Posted by Dave J

Just to give you an idea, I just went down and measured mine and they are 14mm T slots on 44mm centres and there is 18-20mm between the bottom of one T slot to the other.

Dave

Roger that .... I think mine is similar , probably the same .

I could possibly make a small fixture plate myself with 4 or 5 slots , or tapped holes in rows .. . rather than buying a commercial version . It would work OK for smallish jobs . As Fred said, to a large degree , it's up to ones imagination as to how particular pieces are held .

Would aluminium be a feasable material for a fixture plate ? Machining wide plates to a flat spec. would need a fly cutter I imagine . I might even be able to buy a precision piece of plate somewhere , then all i have to do is mill slots into it ,

Mike

Originally Posted by Dave J

Just to give you an idea, I just went down and measured mine and they are 14mm T slots on 44mm centres and there is 18-20mm between the bottom of one T slot to the other.

Dave

The DM45 has 56mm between the bottom of the T slots, so if you were to use 12mm T nuts, they have an 18mm base, so there would be 19mm left between the T slots. If you used the 14mm T nuts, 22m base, you would have have 17mm left between the T slots.

When I make my tooling plate I won't mill slots in it, just drill and tap holes in a grid pattern with some untapped holes for locating pins.

Originally Posted by Big Shed

The DM45 has 56mm between the bottom of the T slots, so if you were to use 12mm T nuts, they have an 18mm base, so there would be 19mm left between the T slots.

Mike,
That would be fine and enough meat left.
My mill has the thrust bearings for the lead screw on one end, so take one of the handle/ end cap off and have a look at yours. If it is the same see if you can wind the table to the end where you want the T slot to finish with it off. If it reaches you could take out the lead screw when machining it, and put it in the other end so the screw is supported by the thrust bearing.
I hope thats understandable?

I think it will work fine with the dimensions Fred gave, thanks Fred.

Dave

Originally Posted by Dave J

Mike,
If it reaches you could take out the lead screw when machining it, and put it in the other end so the screw is supported by the thrust bearing.
I hope thats understandable?

I think it will work fine with the dimensions Fred gave, thanks Fred.

Dave

Yes I understand ...I will have a long think about it before committing myself and deciding which way to go .

Thanks for the advice and opinions

It is a job thats needs some serious thought, but would be handy to have them now you know the table will still have enough meat to support them.
Who knows if you did it and did a right up, you might have everyone else start doing it as well.

Doing a 12mm slot I would use a 10mm end mill and cut either side on it's own so it was accurate. The HSS T slot cutters can be bought for cheap and I think I saw some carbide insert ones from CTC and a few others.

Going the other way with a tooling plate aluminum would be fine and a lot of people have used it. The aluminum plate is pretty true and they have used it as is. I wouldn't drill your table as this will de value it, just use the T slots for bolts and counter sink them. Ray bought (from memory) a piece of 12mm x 1.2m x 1m and it cost him around $500, but you maybe able to find an off cut big enough to suit your table.
My local off cut place sells them for $8kg and it is all thicker off cuts up to 50mm thick.

Dave

Originally Posted by morrisman

Yeah gang . Great minds think alike . I did think of milling the slots in myself, ' in situ ' so to speak . It wouldn't be a great loss if they don't reach right to the end of the table . A larger machine in a engineering business would do it the whole length , but as you say , it may cost heaps . I will investigate this and think about it . The slots in it now are 14mm by the look of it . Even if the teo added ones are 12mm , it's better than the present setup . Fred, I also did think of the fixture plate as a option . Could be expensive to buy one as it needs to be a precision finish on it . I noticed our friend Harold H uses cheap $15 drill vices for his milling machine . He modifies them somewhat but he says they work fine . He is of the opinion the vices are rarely needed . Instead, he used T nuts and various jigs and packing pieces to hold work down . Mike

I err on the side of caution and use a vise whenever I can.

If I do clamp directly to the table, I try to use stops clamped up against the work to reduce the likelihood of the cutter causing the workpiece to slip. Works most of the time. 2 horsepower has a way of working things loose.

BT

Rick, on the yahoo mill drill forum kindly posted this link:

http://rick.sparber.org/on.pdf

I think it is his own idea ..looks promising .

MIKE


MIKE