Built a few more - Cape Town, South Africa

[Gerald D]

Boss goes with the flow - she is also the bookkeeper of day job where the heaps of steel are ten times bigger. (Our "laser" bill last month was R 205 000!)

[hennie]

Keeping it in the family?

[Gerald D]

Not entirely

[hennie]

MA HOU BY MY OOK `n OOGIE

[ekdenton]

Originally Posted by Gerald D

All the lasered parts are here. Not entirely happy with spider plate bending and took them back today. I have to add a note to the bending drawing that the front face must be flat after bending.

My spider plate was twisted and I wound up spending a few hours tweeking it so that the front face that holds the bearings is flat and level. The bends looked as if they were exactly on the laser etched lines.

It seemed as if either one side of the spider may have bent easier than the other making a slight twist in the final product, or the press brake that they used for my spider was off a little giving slightly more pressure on one side vs. the other.

Maybe it is hard to make that many bends on such a small thick metal and also have the final pc. be accurate??

[Gerald D]

Bending accurately is a black art practised by guys with years of experience. Each bending machine also has its quirks. The guys learn which spot on their machines give the best results.

When I took the 5 spiders back for fixing on Tuesday, I simply had to show the operator what I wanted (spider should lie flat to a table) and he said "no problem!". Now they are 100%. A note on the drawing should help the future guys to have flat spiders.

[Gerald D]

Some pics of what is happening:

gantry stack.jpg

gauge plates.jpg

cross supports.jpg

I must admit that I am cheating - I have staff who know how to read my drawings . They work overtime on this private project for untaxed pay.

workshop.jpg
paint.jpg

[J.R. Hatcher]

Someone's been busy. If you don't mind just make up an extra set of those parts for me. ................ Probably won't take but about 30 min.

[Marc Shlaes]

Are you just going to "pop" over and pick them up?

[RLH3]

So Gerald, did the MechMates get painted MM blue first or did the shop?

Roman

[Gerald D]

The blue theme started with a tool trolley from these guys 15 years ago http://www.gedore.co.za/. The nearest aerosol can of blue I could find to that was "Electric Blue" by http://www.sprayon.co.za/index.asp?pgid=15 (you can see the colour in both those links). When I wanted a standard colour for the MechMates, I asked Sprayon if they had a Pantone or RAL code for their Electric Blue, to which they replied that it is Ford Blue, but they weren't allowed to use the Ford name.

This week we bought 15 cans of Sprayon Electric Blue and have also had 10 liters [2.5 gal] of quick dry enamel mixed to match it.

[Kobus_Joubert]

What a nice sight...The Mech Mate Maternity Ward..MM's are BORN here.

[Gerald D]

Today's spider work has a thread of its own.

The home paint shop:

home paint shop.jpg

Paint baking area - gets hot when parked in the weak mid-winter sun:

back of car.jpg

One of today's products:

hold down roller.jpg

[Marc Shlaes]

Trash bins are your life! Oh wait... you say rubbish bins!

[Alan_c]

What I want to know is how did you manage to find some sunshine? we haven't seen the sun this side of the mountain for three days.

[Gerald D]

My suburb is not called Sun Valley for nothing.

Hey, while you on-line, have you still got your Gabriel gaslift near you? How long is it, fully extended, shoulder to shoulder (excluding tip threads)?

[Alan_c]

548mm extended, 293mm closed.

[Gerald D]

Thanks!

[Gerald D]

The Mcmaster spring is 567mm, which is 19mm longer than the Gabriel, which will put the top bracket back to where the drawings used to show it, which makes me wonder what the other bloke got his knickers in a knot about, and why did I change the drawing to leave lot's of extra meat now? . . . . Anyway, we are out for the evening - maybe "see" you tomorrow.

[Robert M]

Gerald,
Can’t confirm what I’m about to put here since I do not have neither springs.
But the McMaster maybe 19mm longer & by specs ( since I don’t have the real ones) it is shows at a 250mm stroke.
On the other hand, the Gabriel has maybe shorter total extended length ( 548mm) but longer stroke at 255mm ( 548-293=255 ??) !!.
Would it be worth looking in to this just for sake of shorter tube /plate assy and longer stroke availability ??
Just a thought & maybe a good hand !
Robert

[Gerald D]

Robert, the Gabriels are produced here in Cape Town, I don't think that they are available to the average MM builder. The difference between 255 and 250 is too small to be significant. The difference between 548 and 567 is simply a re-position of the upper bracket. All very basic and nothing further to look into.

[hennie]

Gerald will you be using one of cnc directs bob`s?

[Gerald D]

No, they will all be PMDX-122's

[Gerald D]

The bulk of the steelwork has been done. . . . .

003.jpg

004.jpg
(curved tubes are for another job!)

The sideframes above are for tables 4,5 (3.75m X) & 6 (1.9m X).
Table 3 (2.75m X) will be shown in a new thread.
Table 7 (400mm X) is going to mount on the walls of my garage at home.

[isladelobos]

Wow!!

You need a good Garage for install all this machines. nice production.

[Lex]

There is value in a bolted table. I have been thinking of bolting the leg and brace assembly to the main beam as well. The main beam seems to make the sub assembly top heavy(in theory). If the machine gets unbolted and moved it might be easier to protect the rails and gear track from damage. What is your thougths about something like that Gerald?

[Lex]

I must add that I was thinking to make it easier for myself if I had to assemble the table on my own. The four legs with the bracing can be set up first before lifting the main beams in position. Me Crazy?

[Gerald D]

I want to stop the main beams from rocking/flexing/tilting in the y-direction - that is the main reason for keeping the legs and uprights welded under the beam. (I didn't actually see the purpose of the vertical uprights as helping to stop the beam from sagging - the beam is strong enough by itself.)

When the y-car makes sudden movements on top of the gantry, it kicks the beams sideways, and this is the direction in which I have noticed most "hum" from a table. Ideally I would want every single single cross-support welded under the beam - and I probably am still going to do that in addition to the bolts. That would be a very easy weld to cut if the table must be taken apart.

Carrying a side-frame the correct way up is actually easier than the other way around. Just make sure you have 2 trestles to park it on - one at each point and legs simply hang down.

[Lex]

I have decided to stick to your bolting arrangement. I still can't grasp the forces the spindle/ router is appling to the table structure to its full extend. This is something one must experience more than calculated before hand I think.

[Gerald D]

The first thing one must recognise is that the major forces are in the horizontal plane. The dynamic "vibration inducers" are horizontal.

In the vertical plane the thing is more static. We want long term flatness and repeatability of the z dimension. But there isn't anything that really causes up and down bounce.