Folks
I did my 1st clamping of the Horz stab parts last night. I am using some small bessy clamps but they are leaving marks in the wood! I tried popsicle sticks same result. Any suggestions.
I will attach a photo, marks at the bottom are from plastic closepins. I am using titebond II. What do you folks do to avoid this???

***Edited to fix picture upload*** Ken

Thanks
John

It looks to me that the clamps are to strong for the material. If you must use those clamps put 1/4" ply between the clamps and the balsa..

Way to strong of clamps. Use lighter clamps or just put on flat surface & set weight on it.

The above posts are right on the money, those clamps are simply too strong to use on this type of application.

Ken

those clamps look like overkill.I use spring type clothes pins for clamps as well as t pins or masking tape while gluing fuslage sides to formers.I also use x-acto bar type clamps and only use enough pressure to hold the piece in place not enough to crush.you may be able to remove those marks if you spray lightly with water let sit a minute then apply a hot iron.the steam should swell the dented areas as long as the fibers are not broken.repeat as much as neccasary

I had a look at the pic of your bits and the clamp. I have a number of those clamps and wouldn't dream of using them on balsa, they are far too strong. If you are laminating bits you might try pinning them (short pins) over a polystyrene ceiling tile and weighing them down with books.

Another clamp I have used is a plastics molded clamp with a rubber band to provide the pressure, this is of course adjustable.

You can try ply pads under any clamp with the edge of the ply sanded to a small radius.

You may be able to steam out the dents with a LOCAL application of steam.




old git - - - - - - - aka John L.

Thank you everyone. I thought these would work, but no. I will try the steam trick later tonight as I have some sheetrock to do today. I romoved those clamps! School of hadr knocks was in session. I will try the t pins and sand next.

I apperiate the advise and comments folks. thanks
John

you can use them but I would use scrap pieces of light ply between them and your part. for clamping small pieces or very long parts such as fuse doublers like was said here use books, or some type of flat weight. I use red bricks for flat parts on top of a book. look at your hardware store and get those adjustable type clamps you can apply the pressure you need and they have swivel ends at the jaws normally so you can clamp angles.

If you need scap balsa I can send you some. I have plenty. Most still look like kind of like planes though if thats alright.
venom

I use those clamps for work there way overkill,sometimes I will use them if I need to clamp hard wood or ply, try Home Depot or Lowes for the small plastic clamps they have a floating pad at the ends for a flat clamping surface there plenty strong for modeling.
usually I just pin the wood to a flat surface over wax paper so it doesn't stick to the surface or your plans.

If these parts show on your model you will need to fix the clamp marks. If they don't show I would not bother with it as the crushing does not appear to actually break the wood causing weakness of the parts. Now this is how I would fix the parts and you can use this process for most any dents, cracks, gaps and repairs. The first thing you will need is some Red Devil Lightweight wall spackling you can pick it up at most hardware stores. Simply put a glob on the part use an old credit card and swipe the golb of spackle over the dents and let dry. Sand and repeat till smooth this stuff sands so easy and weighs very little plus you can fill some very large gaps with it and covering sticks to it good too. As you can see in my sample pics you can often get a good smooth covering the first swipe across the dents it will dry harder than the balsa but just as easy to sand. I use it for all my filling needs from pin holes to the usual dings, dents and gaps during construction. Try it you'll never be without it!

I agree with aerowoof, try the water and steam method first. The balsa will swell with the steam. Depending on the depth of the marks, it may not come all the way up to the surface. Final solution is to add putty or spackling compound.

These are the clamps I use for my building needs (see attached photo). My favorites are the Hayes clamps and the ratchet-style. The clamps you used are good to use for hardwood applications but that’s about it. These clamps shown are well worth the expense.

A) Traditional clamps with swivel clamp heads.
B) Simple bag clamps for keeping opened bags sealed. Works great as clamps.
C) Hayes adjustable clamps. Rubberband tightness can be adjusted for precise tightness you want. Can be found at towerhobbies.com
D) Ratchet-style clamps. Handles squeeze together for precise tightness you want. Press the small button on the handle to release the pressure.

All of these work great and will not leave marks in most woods. Soft wood can still be left with impressions depending on how soft the wood is but I remedy that by slipping a small piece of ply between the clamp heads and the wood.

For applying wing-sheeting I either use clothes-pins or usually masking tape to hold down.
For clamping the fuselage I usually use masking tape or rubberbands but if really need to use clamps I use C-clamps or the long carpenter’s clamps.

You might also want to invest ina few cheap 4 and 6 inch bar clamps to hold the fuse together while gluing. I found the large pads on the bar clamps don't mar the surface as bad

Good luck with the build I am hoping to maiden my most recent build next week.

TD has the clamps in his photo's I was talking about, one way that has helped me take out dents from balsa as well as other woods is use a 50/50% denatured alcohol and water mix the water puffes the balsa up and the alcohol helps it to evaporate quickly,also windex will work well also it softens the wood and will swell it up to remove dents I use both methods for removing dents and dings I sometimes get in balsa sheeting, swells them out great, then just a quick sand job to smooth things out.

Thank you everyone very much! I was able to get the dents out with the steam trick offered, worked great. Yesterday I tried wooden clothes pins, weight and both worked well. Plus I tried a small set of adjustable quick grips ~ 2" Worked great as I could adjust the pressure.
I am going to use weights and pins tonight as I need to glue my horizontal stab. I fit all the parts Yesterday but last night I was to tired to deal with the glueing at 11:30


CM, good luck on your maiden flight and leave the "Law" at home.