Parameters of a Pattern

[Anonymous]

Hi all,

I'm trying to create a pattern on a part, the spacing and the amount of repetitions are determined by the length of the part.

i would like each repetition to be 1250 apart and be repeated for the length of the part.

Not sure if this is possible or if there is a way around this?

Thanks in advance!

Luke

[mdavis22569]

Share the part ..

but is would be 

say quantity of holes is something like Holes X (Part_Length/1250) 

[Mark.Lancaster]

@Anonymous

Welcome to the community...

Is the start of the first hole a certain distance from the end of the part?

Is the last hole in the pattern a certain distance from the other end of the part?

If not then I would assume the starting and ending holes are the same distance from their related end, is that correct?

Most likely you will need to use the round and ceil function since working with certain distances could yield 10 1/2 holes as an example.. 

Like @mdavis22569 stated.. Post the part or show us an example of what you're trying to accomplish.

[Anonymous]

Thanks for you reply,

The first in the pattern is the far right bottom extrusion and the others are 1250 spacing and Qty is 6 ul. I would like the qty to be determined by the length of the center extrusion, for example 1 ul for every 1250mm of the center extrusion?

hope this makes sense.

[mdavis22569]

yes ..

Like I was mentioning, it's not 100% complete without seeing the IAM on my pc

But hole= Length/1250. 

if you have a length of 3750 you'd get 3 holes, and 7 holes for a length 8750

[Curtis_Waguespack]

 Hi luke.womersley,

Here's a real quick video to show one method of doing what I think you might be after.

I hope this helps.
Best of luck to you in all of your Inventor pursuits,
Curtis
http://inventortrenches.blogspot.com

[Anonymous]

Yes this is what i mean! i have already go to this stage, however when the model is made longer the patterned blocks are spread further apart as shown in your video also, but i would like to keep them a certain distance apart at the same time, so as i increase the model length it simply adds an extra block in every ??mm.

is this possible, or is there a better way to achieve this? 

[Curtis_Waguespack]

Hi luke.womersley,

Ooops! Yeah I missed the part about "standard spacing" yesterday didn't I.

I'll try and post back later if no one beats me to it, but yes this can be done as well.

I hope this helps.
Best of luck to you in all of your Inventor pursuits,
Curtis
http://inventortrenches.blogspot.com

[mcgyvr · Accepted solution]

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@Anonymous wrote:

Yes this is what i mean! i have already go to this stage, however when the model is made longer the patterned blocks are spread further apart as shown in your video also, but i would like to keep them a certain distance apart at the same time, so as i increase the model length it simply adds an extra block in every ??mm.

is this possible, or is there a better way to achieve this? 

---

Have you tried what @mdavis22569 has been telling you?

Thats how you do it..

What part aren't you able to accomplish?

Its all about creating formulas.. Like setup a user parameter called blocks and set it to Length/1250in and using "blocks" for the number of elements in the pattern..

So if Length=12500 the blocks = 10

There is also a "round" (up and down) function

floor(expr)	unitless	unitless (Next lowest whole number.)
ceil(expr)	unitless	unitless (Next highest whole number.)

http://blog.ads-sol.com/2014/07/rounding-inventor-parameters.html

If you can't figure it out please just post your part (ipt file) and give us the numbers to exactly what you want to happen and someone can just do it for you..

[Anonymous]

Hi Luke,

If I may, I would like to try and explain what Curtis and Mcgyver have been saying. First though, I would like to go over rectangular patterns. You may pattern a part based on two criteria per each of the two directions you may specify. These criteria are Instances and Displacement; how many you want, and how far apart you would like the center distance between them to be along your chosen direction.

It sounds like you would like for the Displacement to remain the same, and for the Instances to be driven by the length. No problem! In the Instances field, grab the length dimension like what Curtis showed in his screencast, and divide it by your desired displacement. If that gets you one instance too few, tack on a "+ 1 ul" (i. e. -- Length / 1250 mm + 1 ul). 

However skilled you and I may or may not be at explaining things, you will not be able to garner a specific solution without posting the part.

Curtis, you showed me the "Show Dimensions" feature in rectangular patterns. Thank you!

[Anonymous]

Excellent! this has worked thanks, didn't fully understand i before.

one issue i do have is that i now cannot reduce the length below 7m (for future models) is this locked to a minimum amount of blocks maybe?

[mcgyvr]

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@Anonymous wrote:

Excellent! this has worked thanks, didn't fully understand i before.

one issue i do have is that i now cannot reduce the length below 7m (for future models) is this locked to a minimum amount of blocks maybe?

---

Just post the part as you have it working (partially) now..

FYI... ALWAYS post the part whenever you have a question (unless doing so would put you into NDA (non-disclosure agreement) trouble,etc...).. Its worth 1000 words (or more) and can prevent us from having to ask questions and wait for your response.. then ask more questions,etc...

[Anonymous]

Here is the part file.

The model is working as i want it to, but won't let me reduce the length below 7 meters for some reason

[salariua]

Hi @mcgyvr and the rest; there is an issue with round, ceil, floor expressions

Toward the end of that blog I have a link and if you follow it you find the explanation of the rounding problem. 

This was a hidden remark which I found ONLY in the help pages of 2014 and 2016 (after long searches) which states:

“

Units are evaluated before the arithmetic portion of an expression. Therefore, the power operator applies to a unit before it applies to an adjacent numeric value. For example:

2 m^2

does not evaluate to 4 square meters, but rather means 2 square meters. The correct syntax is:

(2 m)^2 = 4 m^2

“

Why is this hidden from the rest of the help pages I don't know....

Here's the full thread.

Good Luck.