Wood Strips to Airfoil 4 place Bearhawk Kits.

[schu]

Hello all,

I have access to a CNC laser cutter and took some time to develop the rib profiles to convert the 4-place bearhawk kit to using the airfoiled ribs. In the past Mark has sold these, but doesn't really have a good way to get them made consistently, so I thought I would offer them to other builders.

What you do is paypal me $225, and I mail you ribs and some T-88 glue. You sand the burnt edges a little, scuff the elevator ribs, glue them on, then seal them up with poly. Once installed you will want to set your horizontal stab to 3* incidence instead of 4.

The result less drag and slightly more elevator authority.

Thanks,
schu

[Mark Goldberg]

I was wondering how laser cut wood. And why it didn't start burning. But sanding off a little the dark outer surface does not sound too bad.

Matt Schumacher has generously offered to make these parts instead of me having them made here. He based the sizes/shape of the wood strips on parts he had gotten from us/Bob's drawings. So the wood strips should work fine, and thanks Matt for doing this. Mark

[schu]

It’s just like a model airplane, which are all laser cut. You just take some sandpaper and sand off the burnt part which doesn’t take that long.

I’m going to send some T-88 with the strips so that people have what they need and I know they are using good glue.

Thanks Mark

[muleyman78]

Please give me a text or call i want to get some. 8017076136

[svyolo]

Nice.

The original Christen Eagle kits, in the 80's, famously came in crates, bound with synthetic strapping. On the outside of the crate, there was a single edge razer blade attached to cut the strapping. Next to the blade, was a bandaid in case you cut yourself with the razor blade.

[Peter Bishton]

Hello team Bearhawk
does anyone know if we are able purchase the drawing for the new horizontal tail and it's section, if someone wanted to make the horizontal tail feathers to the new design. Does Bob sell that drawing ? Can it be emailed out if you can pay by PayPal? Regards peter

[Bcone1381]

http://www.randbaircraft.com

This is Bob Barrows website. I would call Bob using the phone number in the "Contact Us" link. He's on your side and very good to deal with.

[marcusofcotton]

and please report back with the results

[schu]

I would think that Bob would sell you the updated Bearhawk Bravo plans, and it would be up to you to build/modify the ribs in his plans....

Or you could just mock up a NACA 0012 airfoil the correct length and build your own ribs.

Or you buy a rib package from Mark Goldberg and cut out the existing ones and reweld them in.

Or you can buy new stabs from Mark.

Or you can buy wood strips and glue them on.

All of the above works.

[Peter Bishton]

Thanks Gents
Peter

[marcusofcotton]

Schu, I sure like the looks and work savings of your kit, but I'm still a long way out from that point. As I'm always thinking about aft weight with my light engine/prop plan, what does a set weigh?

[schu]

Not sure, I have some in the works right now, I'll weigh them when they are done.

[schu]

So we have been working on updating the ribs and because they are laser cut, we can now laser engrave the rib number on the side. They are numbered rib 1-4 for the horizontal stab and v-stab for all 4 vertical ribs since it's obvious which are the uppers and lowers. The weight is right at 1.5lbs.

[muleyman78]

I received mine and I'm installing. They are well built. Plan on spending some time sanding though. Doesn't come off easy. I also looked into making my own and the amount of time you will spend trying to convert mm to inches on the airfoil creator will make buying them from Schu a no-brainer . It's a large guessing game to get it right. Seems simple at first to input the mm you need into the system but it wouldn't print right sized. After an hour and 20 pieces of paper I had 1 rib template made and I hadn't even cut a piece of wood. Then take that amount of time x 6 ribs and his price quickly becomes affordable lol

[way_up_north]

Hello all,

I have access to a CNC laser cutter and took some time to develop the rib profiles to convert the 4-place bearhawk kit to using the airfoiled ribs. In the past Mark has sold these, but doesn't really have a good way to get them made consistently, so I thought I would offer them to other builders.

What you do is paypal me $225, and I mail you ribs and some T-88 glue. You sand the burnt edges a little, scuff the elevator ribs, glue them on, then seal them up with poly. Once installed you will want to set your horizontal stab to 3* incidence instead of 4.

The result less drag and slightly more elevator authority.

Thanks,
schu

You should think about doing a scratch builder starter kit....

all the rib formers laser cut....only sold to registered plans holders.....

just do one of each we could then router the other to make the pair....

[schu]

The laser only cuts wood. If you want steel corners rmtalj to Mark

[way_up_north]

The laser only cuts wood. If you want steel corners rmtalj to Mark

What im talking about is the wood formers we make when we're scratch building....

we make wood formers for the tail ribs....wing ribs...flaps...etc....

This video gives you an idea of what I'm talking about...