Budget Wild Thing

[stablgr]

After a reasonably successful scratch build of a Hydromite I've been bitten by the bug and want to turn my hand to something a little bigger. Unfortunately the Hydromite never quite made it to the water. Not long after it was completed we moved house and it kind of got crushed by the movers. My wife told me it was my own fault for leaving it lying around!

Anyway after searching around at all the options I decided on a scaled down Wild Thing. After getting my hands on a copy of the 48" plans I scaled them down to 32" and spaced the stringers a little further apart at 4" to make a little more room in there. After sorting out the drawings I decided to make a mock up in card just to check that everything would go together ok, and before sending them out to get a quote on laser cutting the parts.

Lots of card and PVA glue later this is where I'm at...

Now, as the title suggests I'm looking to do this on a budget an as such am not looking for an out and out speed demon. As far as power is concerned I was thinking of a Graupner Speed 700 BB (6316) running on ten NiMH cells. As a relative, ok total newbie, I have no idea if this will work. Is this a viable option/combination for this size of hull and what sort of performance is it likely to achieve, and what current can I expect this set up to pull? What sort of prop size should I be looking at? Will it even get on the plane?

There are so many questions.....

I had a load of fun building the Hydromite and received a lot of help and advice from this forum...... thanks guys.

I'm hoping the Wild Thing will be even more fun.

Thanks,
Gary

[n.h.schmidt]

Motor for Wild Thing

Hi
A 700 motor can run a 32 inch mono well. If you are going to use a Graupner 700 motor you would only want the 8.4 .I don't know the part number. If you haven't already bought the motor ,Offshore sells a better 700 motor ,the 700sc. It will be faster than the Graupner . You will be really limiting your boat if you use only 10 cells. With 12 cells or 4s lipos you could have a 30mph + boat.With 10 cells you are looking at closer to 22 to 25 max.
For props you would want something like a 42mm on the small end and 45 on the bigger end. Offshore has the Very good Graupner CF K series props . The K42 and K45 are outstanding and low cost.
n.h.schmidt

[stablgr]

I saw the OSE 700 but with the poor exchange rate and the postage involved to the UK I think for what I'm after the 8.4volt speed 700 should fit the bill, but I may increase to 12 cells.

After a few more adjustments to the drawings I bit the bullet and went and got the parts laser cut as I thought it would save a bit of time over cutting them out by hand. Even though it felt like cheating

The good news is the parts arrived today. The bad news is all the 6mm parts have been supplied as two 3mm pieces that I need to glue together. And what's worse is that they are not flat!

They're currently on a flat surface with a lot of weight on them for a few days/weeks in an attempt to straighten them out. That, and the glueing and clamping process to join them should hopefully cure the problem (fingers crossed).

[stablgr]

Any suggestions on the best glus to use for laminating the sheets of ply?

[j.m.]

1st: Epoxy

2nd: Gorilla glue

3rd: Waterproof wood glue (titebond III)

Oh, and a lot of weight and two flat surfaces.

[stablgr]

Hmmmm, not much/any improvement on straightening out the stringers. I was thinking on soaking them in water then clamping them flat and letting them dry out like that.

Any thoughts?

[stablgr]

This is how they all look at the moment...

[kookie_guy]

Personally, I feel the company that cut them for you owes you straight pieces. There's no reason for them to be that warped. They need a new method of storing their wood if it's bending/warping that bad on them.

[CornelP]

Well, first of all, kookie guy is right. This is, unless you gave them the wood. I had the same problem, but my wood was straight to start with. BUT not dry, so when they start cutting... it warps. Water is a good solution, but for ply you should really try steaming it... you need the heat. The only problem will be drying: it can take up to one week or more to achieve complete dryout... depending on your atmospheric humidity. Just leave them in a well ventilated area and wait... do not take the weights/clamp off sooner than 1 week.
One other problem with warped pieces: if these were warped before cutting, your cuts are not 90 deg, so you will have a tough time aligning.

[stablgr]

Yup, I agree that I probably should have returned them (they supplied the material). And you're right about the cuts, they're not at 90 deg. But I don't think that's due to the warping of the material. Even on the smaller pieces that aren't warped the cuts are not truly square, buy i don't think that it's so bad that it'll give me any serious problems. Maybe it's something to do with the way their laser is set up????

Anyway this is what I have to work with right now. Looks like this afternoon I'm going to try steaming them with an iron. Not too bothered about the drying time as I'm off on holiday next week so it should give them plenty of time to dry out while clamped straight.

Thanks for your help guys.

[CornelP]

Small parts look straight, but the big piece of ply was not... I hate it when this happens...
Best of luck!

[stablgr]

Thanks Cornel. The offending parts were thoroughly steamed and clamped flat last night. I'll leave them there until the end of the week and see what they look like. Fingers crossed!

[stablgr]

Lots of steam, pressure, time and glue later.......

[ace028]

Looking good man, can't wait to see some more progress.

[CornelP]

Looks perfect! Just think about the motor, you can still get some good prices on a brushless. For this size boat, a 540 11S or 14S from feigao will do the job nicely on 3S.

http://www.astecmodels.co.uk/catalog/product_info.php?cPath=24_46_73&products_id=481

with

http://www.astecmodels.co.uk/catalog/product_info.php?cPath=3_28&products_id=461

and

http://www.astecmodels.co.uk/catalog/product_info.php?cPath=25_50_58&products_id=345

or bigger, they are cheap enough... and all in the UK.