Hatz Biplane Association

I have spent several evening reading thru many of the post in the archives and this is all very exciting. So many different ways of getting to the same results.
A couple questions for you experienced builders,
1) How much time savings buying a MAKELAN welded fuse?
2) How difficult is it to weld the fuse and the estimated cost of welding your own?
3) Can I get a copy of the CAD files for all the flat fittings?

I have not ordered my plans yet, the wife is getting them for me for Christmas (the complete plans package). Does the plans have a complete material list ie: spruce, ply, 4130, fasteners ?

I don't want to bore too many peopler with stupid questions I just want to make sure I get started off on the right foot. My plans are to build the wings from scratch and once I have the wing buit either buy the fuse or start welding my own. I want to mount a R3600 and I need to look deeper into what mods need to be made to mate that engine to the airframe.
Later!!
Anthony

Hi Anthony,

Here's my take on things:
1. Time savings buying a welded fuse? Hard to say for me. I'm just about to start mine, but I took a few months to learn welding first. So if you factor that time in it might be several months. However, you also have to think about the lead time from Makelan... how long does he take to build and deliver the fuse? Are you really saving a LOT of time?? Depending on where you are in the project you could find yourself on hold waiting for the fuse.

2. Difficulty in welding the fuse & estimated cost? I see it as more time consuming than difficult. As for cost. I have around $2k in steel, plus $500 in welding equipment (gas)... so for me it's $2500 vs. paying Makelan $15k (or whatever the current price is).

3. PM or email me a shipping address and I'll get you a copy of the CD with the fittings.

4. Mods to mount the Rotec. You won't need to change the fuse for the Rotec, just build your own mount, which you would need to do anyway regardless of engine.

5. Materials list - The plans do not have a full bill of materials. Many of the pages have parts listed petaining to that particular page, but there are some errors in both part # and qty, so you are best served by carefully reviewing the pages and building your own list. I'm sure folks on here (myself included) can provide lists that will help get you started. As for the steel, there is no master list of required materials so I reviewed all the pages and built my own list... we'll see how good a job I did over the next few months.

One other comment on welding, Even if you buy the Makelan fuse, your still going to have to weld... compression tubes, struts, fittings on the fuse for mounting things, landing gear, engine mount, emmpanage, etc. When I considered all that I chose to weld the fuse and put the money towards the things I can't build like the engine and flying wires. If you use your time wisely you can cut your own time down - i.e. practice welding while waiting for a rib to dry in the jig and kill two birds with one stone. Doing that for 20-30 days of rib building will get you up to speed pretty quickly.

Doug,
Thanks for the tips. I am not up to speed at all on the welding. I assumed the prefered method for welding was TIG. I was thinking I was going to need to invest $2500 in a decent welding rig.
Another poor assumption on my part was that all the fittings were welded to the fuse before they powder coated, that does not make a bit of sense to me at all. If I have to weld any on the fuse I would go ahead and just weld my own and save the $$$$ as you suggested.
I will definetly have plenty of time to get used to welding before I get to the fuse and I have a couple of good friends who can walk me thru it, one is a professional welder.

I will send you a PM with my address.
Thanks Again!!
Anthony

Hi Anthony,

Don't let me disuade you from TIG. I chose gas because:
1. it's cheaper than TIG to start
2. I didn't know if I'd enjoy welding (I do) hence #1 above
3. there are times when you'll need a torch

However, gas vs TIG is like Ford vs. Chevy. There are two camps who will each tout the superiority of their chosen method. There's nothing wrong with TIG for aircraft welding.

I don't have any direct experience with the Makelan fuselage, but others on here do so I'm sure they can speak to how it is delivered. I understand it is a superb piece of workmanship and I imagine that is it welded up to include all the fittings as drawn on the plans. My point about fittings on the fuse was that if you do something other than what is on the plans (we ARE experimental, after all ) then you may still be faced with welding on the fuse.

Hi Anthony,

I'll throw in my $.02 on welding.

I new how to OA weld farm machinery before I started, but i blew a big hole through a tube the first time I tried to aircraft weld. Thin walled tube takes practice.

I tack welded my whole fuselage together before finish welding, and that gave me several months of time to practice-weld bits and pieces. The practice welding is great because you can destructive test it. (IE slice it in half to check penetration) I got tons of advice from folks here, got a great aircraft welding video lesson from http://www.tinmantech.com/ (also picked up a great mico midget torch) and practiced, practiced, practiced. There are also some good books like Aircraft Welding by L. S. Elzea. Check Amazon.com.

I chose OA over TIG for several reasons.

1. It's time-tested.
2. There are tons of "old timers" around with experience and wisdom to share.
3. You have to normalize a TIG welded cluster with OA again anyway.
4. I already had some OA experience and was comfortable with it.

But many folks to TIG very successfully, and honestly I think the welds look nicer in the end.

Hope that is helpful.

Nick

Thanks for the reply guys,
I will definetly check into and try both methods. I will buy some test pieces of 4130 and try both. I am going to buy a good OA torch and a buddy is going to let me borrow his Lincoln Tig welder. I will do plenty of practice welding and also get some professional instruction on both methods. I am lucky in that respect as we have certified welders where I work and talked to all 3 of them today and they are willing to show me the ropes and help weld the fuse. One of the guys in an artist with a OA torch and the other 2 are certified on aerospace parts with a Tig. Doesn't get much better. I think I can get the whole fuse tacked together and they will help me finish the welds.
With all the resources I have available I wouldn't make much sense to buy the welded fuse, I will put the money to better use elsewhere on the Hatz.

Another probably stupid question, they advertise that they pre drill the tubing on the MEKLAN fuse to pass anti-corrosion fluid thru the tubing after welding. Is this something everyone does ? In one aspect it seems like a good idea for the corrosion protection but it also seems it would weaken the tubing.
Thanks Again!!
Anthony

All of my weldments came from makelin. Leadtime is an issue because their primary business, racing roll cages, take precedence. If timing were the only consideration order the fuselage now and go to work on the wings.

Mine is the only Classic flying with the R3600, but by the time you get ready to work on the motor mount there will be a lot more experience out there. We lowered the thrust line 6 inches to get the engine centered on the fuselage. That then necessitated relofting the formers from the rear cockpit forward to flow the shape. It wasn't difficult but when you are finished yours will be one of a kind

John's got a great Hatz.. .I had the chance to sit in it @ OSH this year (thanks John!).

I just want to clarify one point... as John mentioned, With the Rotec you will have to lower the thrust line and also build different formers for the sides, but to your earlier question about changes to the fuse for the Rotec, these are not changes to the fuse. Correctly locating the engine is a product of building the engine mount and the formers are the wood pieces attached to the side of the fuse. So you can build the fuse per plans and still mount the R3600.

Personally, I weld it myself... especially since you clearly have a wealth of experience at your disposal. Another consideration... if one day you bend the airplane (God forbid) you can fix it yourself.

Thanks again,
Fomers and stringers are something I am very familiar with and very comfortable work with. On my models I prefer to mark the location for the notches in the formers for the stringers with the formers mounted to the fuse, get a better alignment that way. I was thinking maybe a little change to the firewall shape might be in order as well ? Blend the fuse to a more round shape at the firewall. More like the WACO YMF-5. I haven't taken a close look to see what eveyone else is doing with the R3600 installation yet.

So many different things to look at and consider. I will also find out in the next couple of days If I will be doing another product review on an R/C plane. If so I will be building one more before starting the Hatz. Once the Hatz is started R/C building will be on hold until the Hatz is completed.

John I have seen pics of your Hatz and it looks great. I am hoping to make the trip to Oshkosh next year and get a look at some nice planes.
Thanks again for all the tips and advice.
Anthony

Good luck, Anthony. I sure wish i had all your resources when I started!

John, how's that Rotec working out? There seems to be an element who believe Rotec engines are unreliable and that Rotec service is terrible. Can you comment? I'd love to have an R3600 on my Classic, but the rumors have me wondering. Would love to hear a real experience.

Nick