Batting helmet questions...

[dung0beetle]

What did you use to cut the helmet with? Did the cut edge need any cleanup before continuing? How do you make a straight cut?

I have never cut or glued this kind of plastic before, so any tips are welcome and very helpful.

 

[SD68]

I used a cut off disc in a dremel tool to cut the plastic. Don't try to cut through all at once. Score it initially then go steadily deeper. I used 5 minute epoxy to glue the two plastics. Just be sure to rough up both gluing surfaces with at least 80 grit sandpaper, 60 or 40 would be better. Good luck.

 

[dung0beetle]

Measure twice, cut once...

I measured and marked it at least a dozen times, and I still cut it 4mm off.

Time to get some bondo...

 

[dung0beetle]

I don't have a dremel (anymore), so I used a razorknife to score it and just kept going a little deeper. It cut pretty clean, but my hand is sore from using it. Next time I think I will spray the scored line on the helmet with wd40 so the blade doesn't grip the plastic as much. It kept getting stuck when it went too deep. Also, a duller blade might help because it would be scratching into the plastic instead of trying to slice through it.

Thanks for the help SD68! The scoring probably made it alot easier and cleaner than just manhandling it and cutting some fingers off in the process.

Well, it is cut now, I am going to get the camera out to take progress pics. All I need now is some bondo and some for sale signs. I don't think I will quarter the helmet, as my head is rather small. Front to back, the helmet is dead on with WOF's template, and it is only a little off on the sides. Plus, it will be going to my stepson after it is painted anyway. After all, this is only a test to see how it will all go together when I make the real one.

 

[Ghostsoldier]

We're cutting our helmets right now....and since my sons have rather small heads, I noticed, like dungbeetle, that the un-quartered batting helmet pretty-much fits the dome base pattern on Alan's templates (pages 9 and 10), so I'm wondering if I could just leave those unaltered...my melon, however, is around a whopping 7.5" to 7.75" or so in size, so I was wondering from SD68 if he would suggest that I quarter my helmet top...and are those templates on pages 9 and 10 the correct ones to use? We tried a "test-fit" using the paper template, and it seems to look pretty accurate (with a thin padding of foam in the crown for the boys, it will bring their eyes center to the eyeslot)...for me, it actually looks pretty accurate also; I'm going to use the deepest of the cut crowns for mine so when I add the padding, it will bring my eyes up to slot-level also. I don't mind quartering the tops, but if I can cut out some extra work, I'd like to....:confused

Also, I can vary the amount of "flair" at the base of the helmet by adjusting the angle and depth of the overlap in the rear of the pattern, right? I want the "thinner" look to mine (I don't really like the wider "movie version" or the "mystery"...I'm more partial to the early DP's width), but I don't want to end up with something perfectly cylindrical at the top and bottom cross-sections, either....any suggestions?

I hope these question make sense!
Rob

 

[SD68]

My helmet is probably closer in size to an MSH2. I actually increased the size of the templates to 107% for my head. Look at Spideyfetts to give you some idea of the size. For the smaller sized heads I would definitely try to eliminate the quartering process if possible. After quartering I would go with epoxy putty of some sort for strength to fill the initial gap then use bondo for final shaping. Just be sure to maintain the geometry of the helmet and keep your spacing even. Hope this helps,

 

[Ghostsoldier]

SD,
I used the template "as-is" (fit to page) when I printed them initially...I think I will go back and enlarge them for myself (I'll try the 107% like you did), and see what it looks like in cardboard...here's a question aimed as using the templates, though....when this thing goes together, do you really have to use the "helmet form" (page 4 and 8), and the "inner surface" (pages 14 and 17), or can you just use the connected pages 13,15,16,18, 19 and 20? I'm not clear on what those first two templates are for, unless it is meant as a "guide" to help in shaping the final helmet, much like the dome and base patterns are....it seems by looking at the other tutorial threads, most guys are just making a single-layer (excepting the cheeks, of course) "wrap" of Sintra...am I missing something?
Rob

 

[SD68]

I used the inner surface and the outer surface The inner surface forms the two back panels after this area is removed from the outer surface piece. Also, after you cut out for the cheek areas it doubles up the thickness in the mandible area to give it the right profile against the visor. Other people have used the helmet form with their cardboard buckets in a T configuration to hold the rest at the appropriate flair. With the plastic and the way the template is designed the plastic will form the appropriate flair because of the stiffness of the plastic. I just double checked against the helmet base template once done. Good luck.

 

[Ghostsoldier]

SD,
Thanks SO MUCH for helping me out, here...I hope I'm not burning you out on this subject...but I think I gotchya....so, the inner surface is the "main" part of the helmet, and the outer surface wraps around that, sort of like a second, 3-dimensional skin (minus the rear panels, eyeslot and cheeks, of course) with the brow-ridge detail and mandible ridges sticking out in "relief", so to speak...is that correct?

Also, I bought two 4' x 8' sheets of the 1/8"/3mm Sintra today for 50 bucks...I'm gonna use it for armor, but in your opinion, do you think it can also be used to make the helmets? If not, I'll have to find a source for the thinner 2 mm (no parking sign) Sintra...
Rob
(PS...I PM'd Spideyfett about his bucket, too....thanks!)

 

[SD68]

I think the 1/8" would get to thick for the brow ridge detail and may not be flexible enough to wrap and form the helmet without heat.

 

[Ghostsoldier]

Thanks again, man...I think I might use a combination of both thicknesses...I'll start on them tommorow!
Rob

 

[dung0beetle]

I will be using 2 thicknesses of 2mm sintra on the inner surface pieces to give it more strength and also to give it a more realistic thickness. I will also be using the Dome Base and the Helmet Base Guides to further strengthen the shape of the helmet. I am going to try this stuff called Quick Steel as filler. I used it to fix a hole in my friend's oil pan. This stuff gets extremely hard quickly. It is an epoxy putty and it can be sanded after it hardens.

 

[dung0beetle]

I used the Quick Steel to fill the hole in the top of the batting helmet, and it hardened enough to sand in about 3 minutes. I used a penny on the inside to keep the putty in its place, but when I tried to get it off after the putty hardened, the penny was stuck on there permanently. I even tried to pry it out with a screwdriver, but it wouldn't budge. I think I like this stuff. The only drawback is the odor...it smells like...roadkill on a freshly tarred highway.