Thread: Scaling a print

One of the useful things about 3D printing is if you already have a 3D design/file, most 3D printing software will allow said object to be scaled up or down by as large or small as your printer is capable of.

What I have wondered about was how good this would be in practice so I have printed out calibration blocks in a few different sizes (ie a 10mm cube design printed out from 5 to 40 mm no issues there) but then I thought what about something really big. Then I thought - that's going to be a lot of plastic to use so why not make something at least (semi) useful in the process.

One thing I have been look around for for some time is a flatter/shallower container for what's remaining in my Trefolex paste container. The reason is I want a container that would be more easily able to get at the paste. As you can see I have been digging into it with pieces of wood.
Trefolex1.jpg
I worked out how much was in the original container and estimated I needed one at ~ 100mm in diameter and 50 mm tall, with the thread on the outside of the bottom, and also without an inside lip at the top.

A screw top container is a good test for scaling because if the top relative to bottom is slightly too small it won't fit fit, while if its too large the thread won't hold

I found a design on thingiverse for a suitable very small shaped screw top container that I had to scale by 10X on the X-Y plane and 5 x on the vertical.

I wouldn't say the result is perfect (the top is a tad looser than I'd really like it) but it's good enough to hold the thread and for this purpose.

Only problem is I underestimated the amount of Trefolex left in the original container as it barely fits in the new one.
Trefolex2.jpg

One problem with scaling is the wall thickness ended up about twice as thick as necessary. which adds to the cost.
However its only printed at 20% fill density which counteracts that to some extent.
It ended up cost about $4 worth of (a more expensive PLA) plastic to print.
I could have used much cheaper PLA but I have run out of this and have it on back order.

Yes I did look thru all of SWMBO's extensive empty container stash.
Either they were glass, push on lids, not size appropriate or had inside lips.
But I'll bet something pops up next week!

Hi Bob,

Nice storage application ! I assume that yours like mine is/was in a tin ?

A trick that I use is to put the tin in a pan of water and heat it up. This serves two useful purposes, one is that all the swarf that you introduced into the paste when using it migrates to the bottom leaving clean paste, particularly if you put a magnet under the bottom of the tin. The other is it makes it very easy to pour into another container, since it is now liquid lard oil plus all the chemicals that are in it.

Both Trefolex and Temaxol behave this way.

Originally Posted by BaronJ

Hi Bob,

Nice storage application ! I assume that yours like mine is/was in a tin ?

Thanks, It was a plastic container - see picture I've inserted into first post.

A trick that I use is to put the tin in a pan of water and heat it up. This serves two useful purposes, one is that all the swarf that you introduced into the paste when using it migrates to the bottom leaving clean paste, particularly if you put a magnet under the bottom of the tin. The other is it makes it very easy to pour into another container, since it is now liquid lard oil plus all the chemicals that are in it.

Both Trefolex and Temaxol behave this way.

Very little swarf in mine. I usually use compressed air to blow any swarf off things like taps before sticking their ends in for a dip.

Good tip on the heating, thanks. I used an old spoon to transfer it to the new container but I still have the original container with a bit left in it so I will get the rest out your way.

When I bought that container of Trefolex about 25 years ago I remember it cost ~$40 which I thought was a lot and said so to the sales man who then gave me a few $ discount.
He also said use about half as much as you think and it will last twice as long which I though was a throw away line but he has proven correct.

I wear a white gold wedding ring (For 43 years now) I was doing some tapping one time and when it came time to finish and wash my hands ......the wedding ring had turned "gold" in colour. The colour would not wash off but did return to "white gold" some days later with no trace of the "Gold" colour
In the words of Julius Sumner-Miler "why is it so"?

Are you sure PLA is resistant to whatever is in Trefolex Bob? Might be worth checking the container walls in a week or two so you don't go to the shed one day and find Trefolex all over the floor.

John- to avoid contaminating the large container with swarf I decant some Trefolex into a smaller container. No lid and a flux brush stuck in the paste.

Originally Posted by jack620

Are you sure PLA is resistant to whatever is in Trefolex Bob? Might be worth checking the container walls in a week or two so you don't go to the shed one day and find Trefolex all over the floor.

Good point - I keep the container out on the bench so I'll be seeing it every day.

Might get a bit of PLA from the scrap bin and wipe some trefolex on it and and warm it up

John- to avoid the swarf issue I decant some Trefolex into a smaller container.

Hi Guys,

Thanks for the suggestions ! Both of mine are/were in tin cans and at least forty years old. The yellow Trefolex ran out a couple of years ago and I've not been able to replace it, the green Temaxol tin is about half full. For years I've just used a small paint brush to apply it to the work straight from the tin, particularly on the mill, I don't think the Trefolex fumed as much as the Temaxol does.

Both in my opinion are better than the Rocol Foam Cut sample that I have tried, the Rocol stuff also stains some materials.

Originally Posted by jack620

Are you sure PLA is resistant to whatever is in Trefolex Bob? Might be worth checking the container walls in a week or two so you don't go to the shed one day and find Trefolex all over the floor. .

6 months on and the container is still like new. I also put some Trefolex on some PLA and pt it in a glass jar in the sum for a few months - no problem. As someone else has mentioned PLA seems to be significantly oil resistant.

That is a great idea. Are you willing to share the stl file? I would like to modify it a bit, add a little lid on top of the screw lid for a brush to get it out and print one for the trefolex I use.

Originally Posted by BaronJ

Hi Guys,

Thanks for the suggestions ! Both of mine are/were in tin cans and at least forty years old. The yellow Trefolex ran out a couple of years ago and I've not been able to replace it, the green Temaxol tin is about half full. For years I've just used a small paint brush to apply it to the work straight from the tin, particularly on the mill, I don't think the Trefolex fumed as much as the Temaxol does.

Both in my opinion are better than the Rocol Foam Cut sample that I have tried, the Rocol stuff also stains some materials.

I have never bought Trefolex myself but have used it several times at places of my employment years ago, but I would have sworn that it came in a tin and was green in colour. I do not recall it being yellow in colour at all but much the same colour as the tin it came in. Perhaps there were several varieties, to suit different materials, like there is with Tap Magic. From memory it worked well for cutting threads.

Hi Rob, Guys,

Temaxol and Trefolex are different colors, one is yellow and the other is green, without going into the workshop I can't remember which was which. But both the tins that I had were 1Lb tins. The plastic ones are a smaller one only about 250 grm, but much more expensive today !

Trefolex used to be in a tin. Nowdays it's in a plastic container, still the same green colour.

Originally Posted by BaronJ

Hi Rob, Guys,

Temaxol and Trefolex are different colors, one is yellow and the other is green, without going into the workshop I can't remember which was which. But both the tins that I had were 1Lb tins. The plastic ones are a smaller only about 250 grm, but much more expensive today !

The Trefolex I have was originally in a white 1L or maybe 750mL plastic container with a green label.