Bumpers a new way: the dart method

FIRST General Forum
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It seems like every team curses the day that they have to cover up those pool noodles! I think I’ve come up with a new way to do the corners that make the process easier; the dart!

A key issue seems to be that its all squishy stuff; most of our kids have never sewn anything! Unfortunately, the many skilled sewing hobbyists out there generally don’t understand how to develop a pattern for something that staples onto wood. I know we drove one to the edge of insanity trying to make a reversible single piece notch bumper :wink: And still ended up with Velcro-on loose end caps… Despite having a functioning specimen from a few years ago in hand to work off of.

As one of the few CD folks that have the unusual intersection of mechanical and sewing skills, I took a look at all of the patterns and how-to documents I could find. Even knowing how to do it, I found those documents confusing…

So, this summer I sewed some bumpers! I realized that I could produce the mitered corners by sewing a dart and then cutting off the excess fabric. In sewing, a dart is something where you mark two lines on the fabric, bring them together, and dew them. They typically come to a point at one end, so the fold goes away to nothing. By doing this, we can cut down on the planning ahead and fiddly cutting. Here’s what one of the corner darts looks like:

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Sew the dart lines together and trim:
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Turn it inside out and you get this. Note that there is is NO seam in the middle of the corner; that’s continuous cloth.
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Similarly, the end of a notch or corner-only bumper gets marked out:
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And finishes as:
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And, because I know everyone wants to see what a reversible corner only bumper looks like all sewn up:
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I also went ahead and make some actual patterns in sewing-speak to help. Here’s one of them:

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So, CD folks, I need y’all to take a look at these and give me some feedback! Or, even better, get some cheap bedsheets and test out the process like I did!

To -somewhat- reduce the length and complexity of this, I built these as standalone documents for each general class of bumper: full square/rectangle, notched/C, and corner only. Plus, the same set for reversible. Yeah, a lotta document work :frowning:
Bumper Covers Corner Only AA.pdf (1.8 MB)
Bumper Covers Corner Only Reversible AA.pdf (2.7 MB)
Bumper Covers Full Square AA.pdf (1.2 MB)
Bumper Covers Full Square Reversible AA.pdf (1.8 MB)
Bumper Covers Notch and C Shaped AA.pdf (1.6 MB)
Bumper Covers Notch end and C Shaped Reversible AA.pdf (2.5 MB)
Here’s the DXF files for the patterns. You will need to edit the line types to suit your laser cutter, or print them 1:1 scale. There are dimensions shown to verify that you got the right scale.
Bumpers.zip (142.9 KB)

43 Likes
2

That’s a lot of work represented there.

We’ve been doing blue bumper material stapled to the wood, and red covers that attach with velcro for quite a while now. It usually falls to me to sew the red covers. I follow a process very close to what you have shown… but have never made a pattern!

This might make the day before our first 2024 competition a lot less stressful (for me). Thank you.

5 Likes
3

You’re speaking my language

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4

Looks familiar XD

credit to @Mark_Wasserman who gave me the template tool.

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5

I hadn’t seen that one before! Very similar technique!

Going to curves on the cuts gives you a more rounded profile to your corners. It doesn’t take a lot to improve the fit on the noodles.

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6

My only suggestion for anyone that sews (a dart or individual pieces) is to at least double up on the stitch. We’ve had a seam fail more than once, so having a second stitch close behind it keeps it from coming undone entirely.

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7

I do 3 or 4 darts per corner to get a a nice smooth corner. Generating fabric patterns can actually be super easy if you’ve got someone who knows sheet metal modeling in CAD. Step by step instructions are at the end of the bumper guide I wrote last year.
Comets Bumper Guide.pdf (2.3 MB)

We’ve been using darts since 2016 and I find that if a single dart is used, your corners tend to get floppy and catch on field elements more easily.

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8

Awesome guide, thanks for sharing!

Is this approach to cutting the solid noodles legal? I’ve never heard of it being done before.
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9

I don’t want to provide judgement but I think the pertinent rule here is R408.C:

All pool noodles used in a BUMPER set (e.g. red set of BUMPERS) may not be modified (with the exception of cutting to length or cutting to facilitate mating pool noodles at the corners as required by R409) or deformed and must be the same diameter, cross section, and density (e.g. all round hollow or all hex solid).

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10

I suspect this is concerning from a bumper functionality standpoint (setting aside the rules) because the corner of the wood backing could easily deform, push into, or otherwise enter the volume of a “solid noodle equivalent”, in extreme circumstances allow you to lead with a wood corner of bumpers

However, I do fail to see how my explanation would also not apply to traditional miter cut bumpers.

So from a intent of the rules via examples given standpoint this method should be added as a new example in my opinion.

As rules are currently written, and seeing bumper rules are basically evergreen , these are not legal by my interpretation. A LRI may be able to shed more light.

(Edit to mods: I blame my auto correct on my phone. Not sure what happened there, even though it did make sense lol)

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A section of vertical noodle on the corners will give you a nice round, assuming that isn’t forbidden too :wink:

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12

I sure hope it’s not illegal. My team has been doing that for the last three years

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It’s possible to fold the uncut noodle around the corner. You have to push it together (compress it) before rolling it around the corner. We’ve been doing this for most of our bumpers since 2017 and it works well enough. I do think that the vertical section on the corner might be a little more durable, though it doesn’t give that large, smooth radius.

2 Likes
14

If it passes inspection I guess it’s legal :man_shrugging:

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I’m pretty sure folks are being facetious, but just in case…

Vertical noodles in the corners are absolutely legal, per rule R409 (assuming it doesn’t change for some reason in the new season. I can’t imagine why it would)

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16

Not an LRI, but:

R409 is inspected with a “punch test”. Punch the corner of the bumper with some force and if you don’t feel the wood/fasteners/other hard parts, it passes.

17

By my read it’s perfectly legal as long as you’ve got pool noodle in some form in the corners. That said, by DCMP this year the corners were pretty soft and I shoved some new noodle into the corners. The box jointed 13ply Okume frames had also broken by this point though so it may just been a particularly violent game/drivers.

Given the condition of the bumpers after DCMP I made new bumpers for Houston bend the pool noodles around the corners without any slits and I can confirm they are both much harder to bend around sharp corners, and somewhat more durable. (I also taped off the plywood box joints and cast them in marine epoxy for maximum paranoia)

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18

The rules just say “filled with noodle material”, and I’ve gotten this through inspection just fine, but it is not as durable and I don’t think I’m going to use slits in the future.

19

Can you expand on this in more detail? Are you saying you covered your bumper wood in epoxy in an attempt to make your bumpers stronger/more durable?

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Ive been sewing for the large majority of my life and i’m annoyed at myself for not thinking of this method lol. It seems so obvious in hindsight, thank you for posting this! Begone are the days of me messing around with pleats for an hour to get the corners presentable :partying_face:

6 Likes