First time using a milling machine

As promised, here's one way of machining the part, building on what Muzzer has said. And I would agree that wood is not really a suitable base. I sometimes use offcuts of MDF when drilling on the mill, but that's about it.

I assume that you need to make more than one of the part? First make a sacrificial aluminium baseplate to hold the part. Then add two tapers to the top edge of the baseplate that match the angles on the top of the part. That way the part can easily be set parallel to the table travel to machine said tapers. I use a piece of gauge plate tapped into a T-slot for quick alignment with the table.

Then accurately drill the corners of the internal pockets, using a drill sized to give the desired internal radius. Chain drill between those holes to remove the majority of the material. An endmill can then be used to clean up the internal edges. I suspect the internal pockets don't need to be that accurate so the milling can be done by eye with reference to the corner holes. One can drill a hole or two right through the baseplate so there is somewhere for the swarf to go.

Then reclamp the part and chain drill, or just mill, the outer profile, using the edges on the baseplate to set the angles.

I expect you can work out the last few operations, as you have already successfully made a part.

Regards,

Andrew

Andrew

thanks for that info I will try that method this weekend as soon as I buy a new endmill!

Still a little unsure about the tapers and how that works

if you could post a diagram of some kind that would be great

the crucial part where the accuracy needs to be precise is the slope

this is where I have to make a carriage to slide up and down

i was hoping to use a t slot cutter if I can find one small enough (around 6.5mm)

This is the next part I need to create or something similar

John

Around 20mm square would be ideal they have to be quite small and a total of 8 I'd need there are 2 for each flap per wing

I've looked on Google but they seem to be really expensive and a bit to big

failing that I will have to attempt making the top one 2mm roller bearings of some kind would work

cheers Andy

How 'scale ' do you need?

You can get nylon blocks that slide in a shaped steel channel as part of devices for stopping doors opening to far. You could copy those.

Neil

Neil

the mechanism will be hidden away so that might work as long as it travels up and down the slope without binding

Andy

Andy

Definitely worth looking at the IGUS catalogue. They do quite a range of linear tracks and runners made from engineering plastics and aluminium. They are surprisingly accurate and I think they go down to quite small sizes.

Ian P

For stuff like linear guides, head over to AliExpress and have a look around there. You should be able to get something delivered in a week or so for not a lot of dosh. AliExpress is not a complete Wild West experience, as there are some safeguards in place to protect buyers like us.

If money is not the issue, how about Misumi. Talk about playgrounds for grownups!

Murray

Andy: Here's an idealised sketch of the part and baseplate that I hope illustrates what I meant by the angles.

I suspect that the use of linear guides for the flap mechanism is rather an over-complication. All the aircraft that I've flown with Fowler style wing area increasing flaps had pretty crude rollers and guides, with a fair amount of play. I recall about 1/4" to 1/2" play at the trailing edge of the extended flap. The problem with a nice accurate mechanism with close fit tolerances is that the whole lot binds solid the first time you try to operate it with the wing bending under flight loads.

Regards,

Andrew

Andrew

thanks for that diagram I see what you mean now

i have done a little work today but not completed the component yet as I need a new endmill to recess the front part

i managed to use the broken one for milling it out

john

they. Look a bit heavy to be honest I may have to make something from alu shouldn't be that difficult if I take my time

I will get hold of a t cut slotter and hopefully if it's machined accurately enough it should just slide on the rail

we will see !