New Mill - Starter Tooling

Looks pretty darn good to me.

A few comments:

A 4-flute TiN cutter will work fine on aluminium alloy. The use of 3-flute cutters is usually recommended to give extra space for swarf. So as you increase chip loads it might be a good idea to go for 3 flutes. The TiN coating will be ok for aluminium, but isn't needed, so no need to pay for it. More esoteric coatings like TiAlN need to run hot (above the melting point of aluminium) to work so are rather less useful.

The cutters discussed above seem to be long series? Unless you're taking really deep cuts there's no need to use them. They'll deflect more, and you pay for the side flutes so if you're not going to use them it's a waste. From memory the standard 3-flute 10mm cutter I use has a flute depth of around 22mm.

Although not definitive climb milling tends to give a better finish on metals, but not on plastics. It's surprising how big a chip load you can take without breaking a cutter. My mill has around 15 thou backlash and it can grab if I'm over-ambitious, but fingers crossed I haven't broken a cutter yet. I generally leave about 0.5mm for a finish cut with climb milling. It's worth noting that with shallow widths of cut the chip load is much smaller than you might think from the feedrate - search for chip thinning.

Generally I cut every which way, I'm too idle to keep winding the handle back to cut in the same direction each time.

Andrew

As Andrew says the long series ones from ARC are not ideal for all jobs particularly as the diameter gets smaller where you may get some chatter when using just the end of the cutter, hopefully Ketan will add some standard length ones to the range. Even on a long 18mm cut like this there is still a lot of unused flute so shorter will be stiffer and allow greater depth of cut without deflection

In the mean time there are standard length Aluminium specific ones in his carbide range that cut even better than the HSS ones and if looked after will last longer so the slight increase in cost is cancelled out.

Hi guys, I havnt replied individually but I have taken on board all your advice, many thanks.

Jason, a question, how did you cut the radiused sides to the left hand block in your first picture. I imagine you laid it on its side, but what tool did you use.

Edited By Ron Laden on 19/10/2018 15:17:49

Ron, have a look part way down this page for making those parts.

Thanks Jason, I would recommend any beginner to read through your Jowitt engine build in the link you provided. It is like a machining guide in itself, I read through all of it and picked up quite a few tips and ideas on "how to do" it will certainly help me.

Good ideas I probably wouldnt have thought of: Mounting the feet blocks on a dowel across the vice top and tangental cuts, then finish with a file for a radiused end. Tap mounted in the chuck with the wrench attached for tapping true to the work piece. Packing up the side of the vice for cutting shallow angles.

Great stuff

Ron

Edited By Ron Laden on 19/10/2018 17:00:43

Well they say the proof of the pudding, the temperature in the shop this afternoon went into the 80,s as it did yesterday and the mills X axis tightened up again, which proves its temperature related. I adjusted the gib screws to a balance of smooth operation with the minimum of play in the table. So it will be interesting to see in the morning when the temp is in the 50,s how much the play has increased.

Have any of you guys experienced this or is it only me who,s mill has summer and winter gib settings...lol

Edited By Ron Laden on 19/10/2018 20:19:00

Never noticed it on any of my machines. If the temperature changes are fairly slow I'd expect all parts of the machine to change temperature roughly together. There'd only be a problem if different materials are involved. What are the gib strip, table and body made of?

Andrew

Andrew, the gib strip is steel and the table and base are cast iron.

Agree with Andrew but one might, pehaps experience a tiny difference if the gib is constrained between the ends and being deformed... only noticed if it is set tight, when cooler, I suppose.

All my gibs are the multi-point adjuster type, so not constrained on length. My workshop has not varied by more than a couple of degrees in the last fortnight. That is 2 degrees Celsius, of course, not 16+.

Problem found and fixed.

The gib was sliding back and forth 3 or 4 mm, it wasnt located on the screw dog points. I removed the gib and it was a bit pathetic to be honest, the 4 dimples for the dog points had no real depth and the positions were off, witness marks from the screws were 1.5mm off centre and all siting at about 2 o'clock.

I picked up the witness marks with a small centre drill and drilled 2mm deep with a 2.6mm drill, the dogs are 2.5mm dia but I allowed a couple of thou for fit. Polished the gib and re-fitted, the screws located as they screwed further in. Adjusted until I had a good feel to the the handwheel and managed to get the added bonus of no play in the table.

I guess what was happening with the high temperature was that the expansion as tiny as it is was just enough to let the gib slide out of postion as they were not located and then lock up.

Ron

Edited By Ron Laden on 20/10/2018 08:44:21

Edited By Ron Laden on 20/10/2018 08:55:54

This is a common problem with these mills. Try modifying the gib screws as shown in ARC's guide to rebuilding the X1 mill: **LINK**

Russell

I know I,m a pain but can anyone tell me what these small blocks which are supplied with the vice are used for, I have no idea.

Ron I believe they are to fix on the bottom of the vice so you can (supposedly) locate them in the table slot for easy alignment with the table, that's if they fit your table slots. I never bothered with mine preferring to 'clock'the vice in with a dial gauge.

Jason

I have just read your full jowett build and very impressed, also do you more details of you vice stop how it's fitted.

Lionel

They presumably are the locating keys (mentioned as supplied with the vise) so hopefully they will fit into the keyways on your table, when affixed to the bottom of the vise to align the base, either lengthways or crossways. Not much use if you are not using the swivel base, I would think.

Edit : not seen the post above - they got there first.

Edited By not done it yet on 20/10/2018 10:16:31

Thanks guys but no, they dont fit my table T slots, thanks for identifying anyway.

Ron

Edited By Ron Laden on 20/10/2018 10:49:24

A bookthat mentions them and may also have other information for you is in this link to Google books.

**LINK**

Martin C

As said the blocks go into the grooves in the bottom of the vice or it's swivel base. Unfortunately they make then all the same size irrespective of jaw width and at 14mm will be too big for a lot of hobby bench top mills.

A quick tickle with a file suggests they are not that hard so could be milled down to fit your slots leaving a small section at the full 14mm so they still fit snugly in the vice.

Lionel, I'll post some details of my vice stop a bit later.

Thanks Jason I will give that a go.

I saved a few bob today, I was walking through the cooking section in a cheapie shop when I noticed a shallow sided roasting tray, it reminded me of a mill oil tray certainly not a millions miles from one. I bought it, it will just need 4 holes for the fixing bolts at £2.99 instead of £32 for the mill tray there was no argument.

The SX2P uses 8mm T nuts which have a M6 thread, they are quite small, in fact the two I used to fasten down the vice look a bit lost and I used two of the small clamp bars to stop the M6 nuts pulling through the vice fixing slots. I guess they do work but by choice I think I would be happier with M8 threaded nuts. I was thinking of making some but even easier buy the 10mm (M8 thread) T nuts which are just over a tenner for 10 off and modify those. The table slots for the top of the T is a tad over 8mm so M8 rod/bolts will fit but there wouldnt be a lot of wall thickness left in the nut top front and back. Plenty of meat left and right and also plenty in the base of the nut. Think I will get a pair of 10mm nuts and see how they turn out.

p.s. Almost forgot to say that the shed was over 80 degrees again this afternoon and no problem with X handwheel so the gib mod did the trick.

Ron

Edited By Ron Laden on 20/10/2018 17:00:19

The tee nuts can be quite hard so may not be that easy to alter.

The slots on my mill are not quite the same width by a thou or three.

I milled down the stops for my vice a bit (easy with carbide tool, I think HSS will be OK) and fitted them so that to align my vice I just push them to the back of the slot.

Note- your vice may be like mine so that without the swivel vice the slot runs along the length of the vice, which may or may not be what you want. Jason seems to have got lucky and has two-way slots.

Obviously if you use them with the swivel vice they will only be as accurate as the alignment of the vice with the base, but you can still remove and replace the vice using them if you don't swivel it.

Neil